With the global population expected to reach over 9 billion by 2050, there is a continuous need to increase food production and buffer stocks. In this scenario, countries around the world, especially developing countries where the pervasiveness of hunger and food scarcity is more acute, are resorting to various counter strategies to meet the growing demand and to avert food insecurity and famine. Over the recent years there has been growing interest to strengthen and intensify local food production in order to mitigate the adverse effect of global food shocks and food price volatilities. Consequently, there is much attention towards home gardens as a strategy to enhance household food security and nutrition. Home gardens are an integral part of local food systems and the agricultural landscape of developing countries all over the world and have endured the test of time.
Through a rigorous literature review, this paper first examines definitions and characteristics of home gardens and then provides a global review of their social, economic, and environmental contributions to communities in various socio-economic contexts. Many of the compositions on home gardens share research and experiences of developing countries in Africa, Asia, and Latin America. These studies recognize positive impacts of home gardens towards addressing food insecurity and malnutrition as well as providing additional benefits such as income and livelihood opportunities for resource-poor families and delivering a number of ecosystem services. However, only a handful of case studies were found on post-crisis settings. While providing a general overview of some of these studies, this review investigates the home garden experiences of post-conflict Sri Lanka, where home gardening has been practiced for centuries. While emphasizing multiple benefits, we also highlight constraints to home garden food production. In conclusion, we emphasize the need for more research and empirical data to appraise the role of home gardens in crisis and post-crisis situations, as well as assessing their economic value and their impacts on food security, nutrition, economic growth, and gender issues.
The vast majority of hungry and malnourished people live in developing countries under sub-standard living conditions  and over half a billion of the global population suffer from chronic food insecuritya. With the global population expected to reach over 9 billion by 2050, there will be a continuous need to increase food production and buffer stocks to meet the growing demand and efficiently cope with volatilities in food production and prices. It has been projected that global food production will need to increase by 70% in order to meet the average daily caloric requirement of the worlds population in 2050b. Moreover, the need for interventions are stressed as the resources available for food production - including land, water, labor and credit - are becoming scarce and costly. The drive for agricultural innovation is further convoluted by the growing issues of climate change and natural resource degradation.
Multiple strategies are required to address the issue of food production and food securityc. The choice of feasible approaches hinges on the existing social, political, and economic conditions and resources available to design and implement the intervention. Home gardens are a time-tested local strategy that are widely adopted and practiced in various circumstances by local communities with limited resources and institutional support. It is evident from the literature that home gardens are a part of the agriculture and food production systems in many developing countries and are widely used as a remedy to alleviate hunger and malnutrition in the face of a global food crisis .
Globally, home gardens have been documented as an important supplemental source contributing to food and nutritional security and livelihoods. 'Food production on small plots adjacent to human settlements is the oldest and most enduring form of cultivation' . For centuries, home gardens have been an integral component of family farming and local food systems. Home gardening is an ancient and widespread practice all over the world. In the literature, home gardens are classified as mixed, kitchen, backyard, farmyard, compound or homestead garden .
This paper presents the developing country experiences of home gardens and looks at the specific case of post-conflict Sri Lankad. An extensive literature search was conducted through the review of over 100 publications, reports, and book chapters, covering various aspects of home gardening to develop the theoretical framework. The inherent characteristics of home gardens as well as the contextual attributes, benefits, and constraints captured in the literature are summarized in the following sections.
Home gardens are found in both rural and urban areas in predominantly small-scale subsistence agricultural systems . The very beginning of modern agriculture can be dated back to subsistence production systems that began in small garden plots around the household. These gardens have persistently endured the test of time and continue to play an important role in providing food and income for the family . Since the early studies of home gardens in the 1930s by the Dutch scholars Osche and Terra on mixed gardens in Java, Indonesia , there has been extensive contributions to the subject synthesizing definitions, species inventories, functions, structural characteristics, composition, socio-economic, and cultural relevance. Home gardens are defined in multiple ways highlighting various aspects based on the context or emphasis and objectives of the research . Gupta pointed out that the background and gender of the researcher or scientist may also bias their perception on home gardens and may not entirely reflect the opinion of the family involved in home gardening activities .
'The household garden is a small-scale production system supplying plant and animal consumption and utilitarian items either not obtainable, affordable, or readily available through retail markets, field cultivation, hunting, gathering, fishing, and wage earning. Household gardens tend to be located close to dwelling for security, convenience, and special care. They occupy land marginal to field production and labor marginal to major household economic activities. Featuring ecologically adapted and complementary species, household gardens are marked by low capital input and simple technology.'
Generally, home gardening refers to the cultivation of a small portion of land which may be around the household or within walking distance from the family home . Home gardens can be described as a mixed cropping system that encompasses vegetables, fruits, plantation crops, spices, herbs, ornamental and medicinal plants as well as livestock that can serve as a supplementary source of food and income. Fresco and Westphal  specify home gardens as a cropping system composed of soil, crops, weeds, pathogens and insects that converts resource inputs - solar energy, water, nutrients, labor, etc. - into food, feed, fuel, fiber and pharmaceuticals. Kumar and Nair , while acknowledging that there is no standard definition for 'a home garden', summarize the shared perception by referring to it as 'an intimate, multi-story combinations of various trees and crops, sometimes in association with domestic animals, around homesteads', and add that home garden cultivation is fully or partially committed for vegetables, fruits, and herbs primarily for domestic consumption.
Adding to this, others have described a home garden as a well-defined, multi-storied and multi-use area near the family dwelling that serves as a small-scale supplementary food production system maintained by the household members, and one that encompasses a diverse array of plant and animal species that mimics the natural eco-system [11, 1719].
Michelle and Hanstad  list five intrinsic characteristics of home gardens: 1) are located near the residence; 2) contain a high diversity of plants; 3) production is supplemental rather than a main source of family consumption and income; 4) occupy a small area ; and 5) are a production system that the poor can easily enter at some level .
There is a vast body of literature presenting research and case studies focusing on the role of home gardens as agroforestry or food production systems, or a combination of both. Home gardens are ecologically divided into two categories: tropical and temperate . Much of the literature focuses on home gardens in the tropical areas in Central and South America . There is also a substantial interest for home gardens in South and South-East Asia  and Africa . Conversely, only a few documented studies exist on home gardens from temperate regions  and from developed countries [32, 3942].
Ninez  lists general tendencies with respect to home garden food production systems based on 15 type-specific characteristics adopted from Ruthenberg  (Table1), and presents an ethnographical synthesis of home gardens across the globe. Home gardens are commonly established on lands that are marginal or not suitable for field crops or forage cultivation because of their size, topography, or location . The specific size of a home garden varies from household to household and, normally, their average size is less than that of the arable land owned by the household. However, this may not hold true for those families that do not own agricultural land and for the landless. New innovations and techniques have made home gardening possible even for the families that have very little land or no land at all . The home gardens may be delimited by physical demarcations such as live fences or hedges, fences, ditches or boundaries established through mutual understanding. Application of kitchen waste, animal manure, and other organic residues has been a practice amongst home gardeners and this exercise has helped to considerably increase the productivity and fertility of these gardens [11, 44, 45].
While some similarities exist across the board, each home garden is unique in structure, functionality, composition, and appearance [13, 4648] as they depend on the natural ecology of the location, available family resources such as labor, and the skills, preferences, and enthusiasm of family members [45, 49, 50]. Home garden cultivation tends to be quite dynamic [17, 18]. The decisions related to the selection of crops, procuring inputs, harvesting, management, and so forth are mostly driven by the consumption and income generation needs of the household [27, 45]. A study from Indonesia observed that the structure, composition, intensity of cultivation, and diversity of home gardens can be subjected to the socioeconomic status of the household . For instance, as the families became economically stable their cultivation shifted from staples to horticultural crops and some families began to raise livestock. Based on the economics of the household, Niez  differentiated two types of home gardens: 1) subsistence gardens and 2) budget gardens. Access to planting material and social capital are noted as important attributes to species diversity in gardens . Collectively, the ecological potential, economic status, and social elements influence the presence of food and non-food crops and animals in the garden [28, 53]. Additionally, Moreno-Black and colleagues  identified that limitations resulting from factors such as opportunities for off-farm employment and family structure as well as local customs influence the development and composition of the gardens.
The home garden frequently uses family labor  - women, children, and elders are of particular importance in their management [46, 48, 5557] but, depending on the economic capacity and affordability, households may hire wage laborers to cultivate and maintain the home garden that in turn affect the composition and intensity of home garden activities [22, 55, 56]. Like any other food production system, home gardens may be vulnerable to harsh environmental conditions such as drought and floods [57, 58]. Despite the fact that home gardening activities demand a lesser amount of horticultural and agronomic know-how, crop losses and other negative implications can be reduced when the household members are empowered with better skills and knowledge .
Home gardens have been an integral part of local food systems in developing countries around the world. Many studies provide descriptive evidence and analysis of home gardens in developing countries in Asia, Africa, and Latin America and pinpoint their numerous benefits to communities and families. They encapsulate perpetual small-scaled subsistence agricultural systems established by the households to obtain and supplement the food requirements of the family. Home gardens are mainly intended to grow and produce food items for family consumption, but they can be diversified to produce outputs that have multiple uses including indigenous medicine and home remedies for certain illnesses, kindling and alternative fuel source, manure, building material, and animal feed. Chris Landon-Lane  provides an overview of the benefits of home gardens (Table2) and describes home gardens as a 'place for innovation' with the potential to improve the livelihood of peri-urban and rural communities. In-depth exploration of past and more recent compositions on home gardens worldwide not only affirms Landon-Lanes insight but also recognize additional advantages. We broadly categorized benefits of home gardening into three components: (1) social; (2) economic; and (3) environmental benefits. These benefits are presented and explained through the vast experiences on home gardens from developing nations around the world.
Reviews of studies from various countries reveal that the degree and combination socio-cultural impacts on societies engaged in home gardening vary across the board. Multiple social benefits of home gardens include enhancing food and nutritional security in many socio-economic and political situations, improving family health and human capacity, empowering women, promoting social justice and equity, and preserving indigenous knowledge and culture .
The most fundamental social benefit of home gardens stems from their direct contributions to household food security by increasing availability, accessibility, and utilization of food productse. Home gardens are maintained for easy access to fresh plant and animal food sources in both rural and urban locales. Food items from home gardens add substantially to the family energy and nutritive requirements on a continuous basis. A pioneering research study on home gardens conducted by Ochse and Terra in the early 1930s  states that home gardens led to 18% of the caloric and 14% of the protein consumption by households in Kutowinangun, Indonesia. Subsequent studies on the Javanese home gardens point out a direct link between successful home gardens and households nutritional status , and observe an increase in households food consumption with intensification of home food production . Javanese experiences illustrating the potential of home gardens to add to households food supply and nutrition [13, 21], as well as their eminence as multi-storied agro-ecosystem [55, 63] in the tropics, heightened the global attention towards home gardens.
Foods from home gardens varied from horticultural crops to roots to palm and animal products; further plants from the gardens are also used as spices, herbs, medicines, and fodder for the animals [53, 6467]. Although home gardens are not generally reputed as a staple crop production base, Thaman  documented that Pacific Islanders obtained their main staple root crops from home gardens. Similar reports were found from Nepal , Yucatan Peninsula , Bangladesh , Peru , Ghana , and Zimbabwe . Resource-poor families often depended more on home gardens for their food staples and secondary staples than those endowed with a fair amount of assets and resources such as land and capital [51, 70]. For poor and marginalized families unable to afford expensive animal products to fulfill their nutritional needs, home gardens offer a cheap source of nutritive foods . Through gardening, households can have better access to a diversity of plant and animal food items that lead to an overall increase in dietary intake and boost the bioavailability and absorption of essential nutrients .
As stated by Marsh , home gardens provide easy day-to-day access to an assortment of fresh and nutritious foods for the household and accordingly those homes obtained more than 50% of the vegetables, fruits, tubers, and yams from their garden. Supporting this premise, different studies conclude that, while adding to the caloric quantity, home gardens supplement staple-based diet with a significant portion of proteins , vitamins , and minerals , leading to an enriched and balanced diet [74, 75] particularly for growing children and mothers . Additionally, plants from the gardens - especially spices and herbs - are used as flavor enhancers, teas, and condiments . Recently, countries like Bangladesh have been successful in increasing the availability and consumption of vitamin A-rich food items through national home gardening programs .
Furthermore, the integration of livestock and poultry activities into home gardening reinforces food and nutritional security for the families as milk, eggs, and meat from home-raised animals provided the main and, in many instances, the only source of animal protein . In some places, home gardeners are also engaged in mushroom cultivation and beekeeping  and even small fresh water fish ponds are incorporated into the garden space adding to the share of proteins and other nutrients available for the family .
Evidence from around the world suggests that home gardens can be a versatile option to address food insecurity in various challenging situations, and thus they have attracted sponsorship by numerous government and non-governmental organizations. Consequently, home garden production has significantly increased in the country and has been instrumental in reducing hidden hunger and disease cause by micronutrient deficiency. In an attempt to assess the dynamics of home garden evolution in Java and Sulawesi in Indonesia, Wiersum  notes that home gardens make available a small but continuous flow of subsistence food products for the household. Also, home gardens provide the main source of staple food for people in heavily degraded and densely populated areas with limited croplands [44, 78].
Home gardens can ensure food to underprivileged and resources-poor households as they can be established and maintained within a small patch of land or with no land using a few inputs [20, 43]. A study of home gardens in Cuba reveals that they were used as a strategy to increase resilience and ensure food security in the face of economic crisis and political isolation . To mitigate recurring food shortage and malnutrition, Cuban households obtained basic staple foods (rice and beans) through rations, but the households relied on their home gardens to obtain additional produce to diversify the family diet . Ensuring a reliable and convenient source of food, fiber, and fuel for the family, they are viewed as a robust food system in circumstances where population pressures and numerous resource limitations persist [81, 82]. In the Peruvian capital of Lima, home gardening has led to nutritional benefits to families living in slum areas by increasing the availability of carbohydrates as well as nutrient-rich vegetables and fruits that are not economically accessible for poor slum dwellers .
The Global Hunger Index specified that the lack of political stability has escalated hunger and poverty in countries affected by conflicts . Similarly, environmental disaster can also have devastating impacts on communities and disable food production systems . Even though there are only a few published narratives, home gardens have been proposed as an option for food and nutritional security in disaster, conflict, and other post-crisis situationsf[9, 45, 86]. Home gardens based on enset and coffee are an integrated farming system that not only provide subsistence and complementary food products for Ethiopian families, especially during famines, but also provide the primary means of employment for the household .
Tajikistan became independent from the Soviet Union in 1991 but was plagued by a civil war soon after. Rowe  showed that, during the post-soviet era, Tajik families tormented by civil war, agricultural downfall, and drought heavily depended on their gardens for food. This trend still continues, and home gardens continue to significantly supplement household food security and sustenance. In recent years, several countries transitioning towards peace and stability and those that are recovering from natural disaster have been adopting policies that support home gardening to reduce the prevalence and severity of hunger and malnutrition [45, 87].
Bandarin et. al.  point out that, in a post-conflict setting, assistance and reconciliation mechanisms work best and result in environmental, social and economic benefits when there is a cultural or traditional linkage between the target population and the intervention. Hence, home garden projects offer a realistic solution as in most countries home gardening is a regular day-to-day activity amongst the household, especially for women. In addition, home gardens when properly managed provide a four-in-one solution to the food and nutrition problem by increasing household food availability, enabling greater physical, economic and social access, providing an array of nutrients, and protecting and buffering the household against food shortages.
Plants are an important source of medicine for humans and livestock and are used as biological pesticides to protect crops from diseases and pest infestations. Herbs and medicinal plants are grown in home gardens all over the world, and in developing countries nearly 80% of the people use them to treat various illnesses, diseases, and also to improve their health conditions . A generous portion of the plants found in home gardens have some medicinal value and they can be used to treat many common health problems in a cost-effective manner. For instance, Perera and Rajapksa, in their assessment of Kandyan gardens in Sri Lanka , note that out of the 125 plant species found about 30% were exclusively used for medicinal uses and about 12% for medical and other purposes. Medicinal plants were documented to be an important plant group second only to high-value species in Sri Lanka  and in Bangladesh . Home gardens in Bukoba district of Tanzania contained plant species grown entirely for medicinal purposes . Around 70% of the plant species identified in forests and gardens in the Yucatan had a medicinal use , and in traditional Mayan home gardens nine species of the 77 useful plants found were exclusively used for medicinal purposes and 26 species had mixed uses as medicines, food, spices, and ornamentals .
Food insecurity and economic hardships force people to consume less and to settle for food that is of low nutritional quality. Adverse health effects due to inadequate intake of basic macronutrients are further compounded by deficiencies in micronutrients such as vitamins and minerals. More than 35% of the fatalities worldwide are caused by factors attributed to nutritional deficits . Amongst them, vitamin A deficiency is a major health issue in many low-income countries and pose serious health problems, particularly for pregnant women and their babies and growing children. Reports indicate more than 7 million women suffering from complications due to vitamin A insufficiency  and cause 6 to 8% of the deaths amongst children under the age of 5 years in Africa and Asia . In some countries where this problem is acute, homestead food production programs have been launched to assist and address vitamin A deficiency and to improve the quality of diet by facilitating a year-round production of vegetables and fruits .
The global incidence of anemia is primarily attributed to iron deficiency. Iron insufficiency elevates the risk of mortality during pregnancy by 20% . Moreover, estimates suggest that nearly one-third of the global population live in countries with high zinc deficiency . Micronutrient deficiency can raise the vulnerability to other infectious diseases and the risks of mortality due to illnesses such as diarrhea, pneumonia, malaria, and measles . It may also lead to poor physical and cognitive development and impairment of motor skills in young children as well as other short-term and long-term health effects. Furthermore, a vicarious cycle of undesirable socio-economic effects can be triggered as peoples ability to actively engage in physical and economic activities are hindered by illness, disability, and reduced life expectancy. In different contexts, home gardening initiatives have been proposed and implemented as potential strategies to address health issues resulting from malnutrition [100, 101]. Although the opportunity is real, minimal efforts have been made to identify and maximize the gross benefits of home gardening for better health.
In many cultures, women play an important role in food production but at times their worth is somewhat undermined. They are also active in home gardening, though their involvement in the home garden tends to be determined by socio-cultural norms . In most scenarios womens contribution to household food production is immense, but this does not imply that home gardening is predominantly a female activity. Womens participation and responsibilities in home gardening varies across cultures, including land preparation, planting, weeding, harvesting, and marketing [54, 102, 103]. In fact, in some cultures, women are the sole caretakers of household gardens [35, 72] while, in others, they play more or less a supportive role . Howards 2006 analysis  of 13 home gardens case studies in South America revealed that women are the main managers of home gardens across the region. Home gardening activities are vital and fit well with their day-to-day domestic activities and employment patterns along with their cultural and aesthetic values. On the other hand, in the Indonesian context women take part during planting and harvesting  and, in Sri Lanka, they provide labor during peak times . Regardless, particularly for women and disadvantaged groups, home gardening is an avenue for social and economic enrichment.
Home gardens stimulate social change and development. Amongst the Achuar Indian community in the upper Amazon, a womans ability to maintain a lush home garden not only demonstrates her agronomic competency but also her status in society . Similarly, for the Saraguro women of the Andes, a plentiful garden help elevates a womans social eminence and demonstrates her commitment to the familys wellbeing . Based on a study conducted in Senegal by Brun and colleagues , evaluating the food and nutritional impact of home gardening, it was found that, although the gardens did not make a major contribution to food consumption and nutrition, they were instrumental in improving the womens income and social status as well as their awareness of evolving food habits in urban areas. For some women, sales of garden products are often the only sources of income or livelihood . In Tajikistan, where many of the men were killed during the civil war or have migrated to Russia and other countries for employment, women, elders and children have been providing invaluable family labor and resources to local agricultural economy. Kitchen gardens, as they are referred to by Rowe , are very important especially for women-headed families in terms of meeting their everyday food consumption needs and generating income. In fact, nearly half of the food consumed at home and one-third of the food sold in the market came from these garden lots. Other studies have shown that, in situations where women are leading home gardens, there has been improvement to household nutrition, especially child nutrition [72, 107].
Through home gardening women have developed proficiency related to plants and garden practices that helps them become better home and environment managers. Their labor is indispensable to maintain the garden and to help keep production cost low. As home managers, women have useful knowledge of numerous domestic needs. By their involvement in the production process, they are able to meet family needs more easily and economically . Home gardeners in Peru indicated that women gardeners are inclined to produce food primarily for family consumption while men gardeners typically focus on high value crops for marketing . While home gardens provide a respectable path for women to contribute to household subsistence, eminence, and character, they hold a greater socio-cultural and spiritual importance for women . Furthermore, they are a key source of gardening knowledge and information .
Research suggests that, in some societies and cultures, a womans role in family decision making is rather limited; however, many accounts confirm that when it comes to home gardening women tend to have more autonomy and decision making capabilities . Moreno-Black and colleagues  conducted a study of 49 womens home gardens in Northeastern Thailand where the rural women constantly indicated that they were the key decision makers and carried out most of the activities of the home gardens.
Home gardens consist of a variety of components and species that represent social and traditional aspects of different societies. This rich indigenous culture and communal knowledge base is expressed through home gardening by the selection of plants and animal species as well as the farming practices used by the local community [16, 70]. Home gardens serve as a valuable repository for preserving and transferring indigenous crops and livestock species, production knowledge and the skills from one generation to another .
Interactions in and around the home garden create and reinforce social status and ties between the household and the community. Home gardeners habitually exchange or gift planting materials, vegetables, fruits, leaves, herbals and medicinal plants for social, cultural, and religious purposes [109, 110]. Such interactions are essential for social integration and building social capital. The social dimension of home gardening is yet not fully explored.
The economic benefits of home gardens go beyond food and nutritional security and subsistence, especially for resource-poor families. Bibliographic evidence suggests that home gardens contribute to income generation, improved livelihoods, and household economic welfare as well as promoting entrepreneurship and rural development [111, 112]. Through the review of a number of case studies, Mitchell and Hanstad  assert that home gardens can contribute to household economic well-being in several ways: garden products can be sold to earn additional income [17, 48, 83]; gardening activities can be developed into a small cottage industry; and earnings from the sale of home garden products and the savings from consuming home-grown food products can lead to more disposable income that can be used for other domestic purposes. Studies from Nepal, Cambodia, and Papua New Guinea report that the income generated from the sale of home garden fruits, vegetables, and livestock products allowed households to use the proceeds to purchase additional food items as well as for savings, education, and other services [85, 113]. Families in mountain areas of Vietnam were able to generate more than 22% of their cash income through home-gardening activities .
Home gardens are widely promoted in many countries as a mechanism to avert poverty and as a source of income for subsistence families in developing countries. Although home gardens are viewed as subsistence-low production systems, they can be structured to be more efficient commercial enterprises by growing high-value crops and animal husbandry . A number of research studies have focused on evaluating the potential or real economic contribution to the household and local economy as well as social development . A study from Southeastern Nigeria reported that tree crops and livestock produced in home gardens accounted for more than 60% of household income . In many cases the sale of produce from home gardens improves the financial status of the family providing additional income, while contributing social and cultural amelioration . The fact that home production is less cost-intensive and requires fewer inputs and investment is extremely important for resource-poor families that have limited access to production inputs. Yet it has been assessed that moderately rigorous crop and livestock production in home gardens can generate as much revenue per unit area as field crop production [9, 62]. Where land constraints exist, innovative tools have been used to make efficient use of limited space . Also, livestock housed in gardens diversify risk due to crop losses and provide a cash buffer and asset to the household .
Home gardens provide multiple environmental and ecological benefits. They serve as the primary unit that initiates and utilizes ecologically friendly approaches for food production while conserving biodiversity and natural resources. Home gardens are usually diverse and contain a rich composition of plant and animal species. Hence they make interesting cases for ethno-botanical studies [110, 118].
Gardens are complex and may resemble ecological agricultural production systems that sponsor biodiversity conservation. The rich diversity and composition of species and the dense distribution of faunal and floral strata denote extraordinary features of home garden ecology [20, 46]. Buchmanns 2009 assessment  of 25 home gardens in Central Cuba noted 182 plant species. Other reports from around the world also identify a significant concentration of plants used as vegetables, fruits, herbs, medicines, yams, and spices [78, 114]. Home gardens also contain a wide spectrum of plant species, some of which are landraces, rare or threatened species, and specific cultivars selected for a set of desirable traits . Thus they become ideal sites for in situ conservation of biodiversity and genetic material [111, 120].
Home gardens also provide a number of ecosystem services such as habitats for animals and other beneficial organisms, nutrient recycling, reduced soil erosion, and enhanced pollination . The high density of plants within the home garden provides the ideal environment and refuge for wildlife species such as birds, small mammals, reptiles, and insects . Calvet-Mir et. al.  highlight a number of ecosystems services provided by home gardens such as production of quality food, maintenance of landraces, cultural services, pest control, and pollination. They conclude that the most important ecosystems services provided by home gardens differ from large-scale and commercial agriculture.
Nutrient cycling is another ecological benefit of home gardens [120, 123]. The abundance of plant and animal litter and continuous recycling of organic soil matter contributes to a highly efficient nutrient cycling system. Another potential benefit of home gardens is the reduction of soil erosion and land conservation [70, 124]. The attraction of honey bees provides added benefits including improved pollination and increased fruit dispersal .
Individuals of the household, animals, and plants all maintain a symbiotic relationship within the home gardens. For instance, the plants and animals provide food and other benefits for the family and the family in turn takes care of the home gardens. Plant materials are used as fodder for the animals and animal manure is incorporated into the compost to fertilize plants, hence reducing the need for chemical fertilizer . Livestock and poultry manure can add a significant amount of organic soil matter, nitrogen, potassium, and phosphorus into the soil. The integration of livestock activities into home gardening can expedite nutrient cycling in ecosystem and help retain moisture .
The economy of Sri Lanka is founded on agriculture. More than 35% of the 20 million people of Sri Lanka are engaged directly or indirectly in the agrarian sectors. Home gardening has been a long-standing practice among the rural and urban households in Sri Lanka for centuries . Despite the traditional basis for home gardening, over the recent years national policies have focused on promoting home gardening in the country. Currently, two national initiatives are underway and are receiving notable patronage from the government for the initiation of a countrywide food production drive to establish one million home gardens across the islandg. The programs highlight the key role home gardens play in the face of food insecurity, economic downturn and malnutrition by providing a diversified source of food and a way of generating income.
In spite of the growing interest in home gardening, literature discussing home gardens in Sri Lanka is rather limited. The bulk of the available excerpts almost exclusively focuses on Kandyan Gardens, also known as Kandyan Forest Gardens (KFG). KFG are a common traditional agroforestry system found in the wet central hills in Sri Lanka. They encompass a mixed cropping system, which includes a diverse collection of economically valuable perennial and semi-perennial crops situated around the household  along with animal species that were raised to suit the necessities of the family, the environment, and the recommendations by scientists and extension workers .
One of the earliest studies on KFG in Sri Lanka was published by McConnell and Dharmapala . From a survey of 30 KFGs established through the use of a farming systems approach they conclude that, although in the short-run KFG were not as productive and profitable as the commercial farming systems, they lead to multiple benefits over time. Jacob and Alles  differentiate KFGs from other mixed forest-gardening systems found in South Asia and South-east Asia with respect to the diversity of plants grown. They also stated that these garden systems improved the well-being of people who nurtured them through the provision of various food products and timber, livelihood opportunities, and sustainability of the production system. Furthermoe, they emphasized the need to inspect existing agronomic practices and to design feasible models that can improve the productivity per unit of land.
Perera and Rajapaksa  characterize various components of KFGs based on ownership, structure, species composition, livestock composition, and management practices. Their baseline survey of 50 randomly selected gardens in the Kandy District showed that the various species in the KFG had numerous uses including food, cash, timber, fuel wood, construction material, green manure, fodder, medicines, shade, and beautification. KFG also have significant implications to the region in terms of in situ germplasm conservation , watershed management , preservation of habitat and other ecological contributions .
A book by Hochegger  offers a comprehensive overview of the ecological, economic, and cultural relevance of KFG in Sri Lanka investigating six locations in the central hills. The Green Movement in Sri Lanka pioneered by Kumarathunga  has published a guide on environmentally friendly agriculture with key emphasis on home gardens. This publication has been initially written in the Sinhala language and is in the process of being translated to the Tamil language. The guide provides step-by-step instructions to home gardeners and farmers on environmentally friendly cultivation and management practices and strategies to boost the efficiency of small agricultural production systems.
Ranasinghe  has developed a detailed manual drawing on the ideas of family business gardens and low/no-space agriculture. This manual was shaped primarily to attract urban households to develop their home crop production into a small agribusiness. In addition this publication attempted to reach a wider audience that includes professionals, non-professionals, entrepreneurs, as well as policy makers concerned with issues related to food and nutritional security in the face of limited resources such as land. It highlights that, through improved management, home garden cultivations can be transformed into agricultural ventures through the systematic adoption of economical and eco-friendly technologies and interventions.
While there are multiple benefits of home gardening for developing countries, the literature also reveals the key constraints to the productivity and sustainability of home gardens and makes recommendations for improving the home gardens and making them a viable and sustainable enterprise. Hoogerbrugge and Fresco  and Mitchell and Hanstad  provide a review of key constraints to home gardening. Among several constraints, they identified the access to suitable and sufficient land to establish a home garden along with lack of ownership and usage rights of some form as the most important limiting factors. The other constraints include access to capital or credit, access to water, seeds and planting materials, weak extension and advisory services, access to labor, and access to markets. The cultural acceptance of home gardening is also an important constraint. Table3 summarizes the most common constraints to home gardening specified in literature by Hoogerbrugge and Fresco and others.
The structure, functions, and contributions of home gardens vary in geographic regions. The literature shows that home gardens fulfill social, cultural and economic needs, while providing a number of ecosystem services. While these benefits are broadly distinguished here for better illustration, these benefits are not mutually exclusive. In the real world, there is substantial overlap and dependence between the various beneficial elements resulting in a bundle of advantages making home gardening initiatives even more attractive.
In the wake of a global food crisis and the soaring food prices, there has been increased emphasis on enhancing and building local food systems. In this context, there is renewed attention to food production and livelihood enhancement through home gardens. However, more empirical evidence on the value and importance of home gardens in conflict and post-conflict situations needs to be researched and documented. There is also a need for research on the cost-benefit analysis of home gardening to determine the economic value and to derive viable models that hold the most promise in diverse circumstances. The areas of nutrition, access to new technologies, extension and advisory services, economic and non-economic benefits, women empowerment, and long-term sustainability of home gardens specifically in post-conflict situations need further research.
Recognizing the value and potential of home gardens for enhancing food security and livelihoods, numerous initiates have been launched by governmental, non-governmental, and international organizations in many developing countries that are providing support and building local capacity to enhance the productivity and also for scaling up home garden activities. In this light, a number of resource materials, manuals, and guides have been developed through various home garden-related projects that can be used to improve and promote home gardening programs to enhance food security [43, 60, 87].
aFood insecurity occurs in three forms: chronic food security is the most severe category where a person is unable to consume the minimum amount of food needed for healthy life over a long period usually due to poverty or lack of productive recourses to generate income to purchase food . Other types include transitional (short-term) food insecurity, which is further subdivided into temporary (limited time period due to shocks) and seasonal or cyclical (trend) food insecurity.
bThe Food and Agriculture Organization  reported an average consumption per person of 3,130 kcal per day by the year 2050 based on their baseline projections. Alexandratos  estimated a slightly lower average daily caloric availability per person of 3,047 kcal per day by the year 2050.
cSince its inception in the early 1970s, the concept of food security has undergone many revisions and has held multiple connotations in research and in policy arenas. The two widely adopted conceptualizations are defined by: 1) the Food and Agriculture Organization - 'food security is a situation that exists when all people, at all times, have physical, social and economic access to sufficient, safe and nutritious food that meets their dietary needs and food preferences for an active and healthy life' ; and 2) by the United States Department of Agriculture - 'food security for a household means access by all members at all times to enough food for an active, healthy life. Food security includes at a minimum: the ready availability of nutritionally adequate and safe foods; and an assured ability to acquire acceptable foods in socially acceptable ways' .
dFor nearly 30 years, the country underwent erratic disorder and military action that caused substantial destitutions to the political and socio-economic structure in the country as well as the infrastructure. The civil conflict was brought to an end in 2009 by the Sri Lankan government forces.
eAs noted earlier there are numerous definitions to food security; nevertheless, these definitions highlight three broad dimensions: food availability, accessibility, and adequacy/utilization  (FAO, 2003 ). Food availability refers to the supply of food made available through domestic production, net imports, food reserves, donations, etc. Accessibility is ensured when an individual is able to obtain food without any physical, social, or economic barriers. Food adequacy/utilization is achieved through various biological and non-biological processes that ensure sufficient energy and nutrient intake.
fOne general connotation for crisis is defined by Gasser and colleagues . Crisis situations are identified as unique and complex in nature and are due to various factors . At times, crisis is unforeseen and inevitable - as in the case of natural disasters - while others may be more protracted and influenced by economic, social, and political changes - such as civil or armed conflict. Irrespective of the origin, crisis adversely affects society by depriving affected groups of their rudimentary and ancillary needs and services including food, shelter, income, health care, security, and infrastructure.
gThe two major national home gardening programs in Sri Lanka are Api Wavamu, Rata Nagamu (Let us cultivate to uplift the nation) and Divinaguma (Livelihood upliftment). In addition, a number of other regional and village level gardening programs are coordinated and managed by international and non-governmental organizations.
Food and Agriculture Organization of the United Nations and World Food Programme: The State of Food Insecurity in the World - Addressing Food Insecurity in Protracted Crises. 2010, Rome, Italy: Food and Agriculture Organization of the United Nations
Johnson-Welch C, Alemu B, Msaki TP, Sengendo M, Kigutha H, Wolff A: Improving Household Food Security: Institutions, Gender and Integrated Approaches. 2000, Davis CA, USA: Paper prepared for the Broadening Access and Strengthening Input Market Systems (BASIS) Collaborative Research Support Project (CRSP)
Gupta AK: Scientists views of farmers practices in India: barriers to effective interaction. Farmer First. Farmer Innovation and Agricultural Research. Edited by: Chambers R, Pacey A, Thrupp LA. 1989, London, UK: Intermediate Technology Publications
Sthapit BR, Rana RB, Hue NN, Rijal DR: The diversity of taro and sponge gourds in traditional home gardens in Nepal and Vietnam. Home Gardens and Agrobiodiversity. Edited by: Eyzaguirre PB, Linares OF. 2004, 234-254. Washington DC, USA: Smithsonian Books,
Krishna GC: Home Gardening as a Household Nutrient Garden. 2006, Pokhara, Nepal: Paper presented at Home Gardens in Nepal: Proceeding of a workshop on Enhancing the contribution of home garden to on-farm management of plant genetic resources and to improve the livelihoods of Nepalese farmers: Lessons learned and policy implications (2004)
Leiva JM, Azurdia C, Ovando W, Lpez E, Ayala H: Contribution of Home Gardens to in situ Conservation in Traditional Farming SystemsGuatemalan Component. 2001, Witzenhausen, Germany: Paper presented at Proceedings of the Second International Home Gardens Workshop,
Aguilar-Stoen M, Moe SR, Camargo-Ricalde SL: Home gardens sustain crop diversity and improve farm resilience in Candelaria Loxicha, Oaxaca, Mexico. Hum Ecol. 2009, 37: 55-77. 10.1007/s10745-008-9197-y.
Cai CT, Luo LS, Nan YZ: Energy and economic flow in home gardens in subtropical Yunnan, SW China: a case study on Sanjia village. Int J Sustain Dev World Ecol. 2004, 11: 199-204. 10.1080/ 469823.
Abdoellah OS, Hadikusumah HY, Takeuchi K, Okubo S, Parikesit: Commercialization of homegardens in an Indonesian village: vegetation composition and functional changes. Agrofor Syst. 2006, 68: 1-13. 10.1007/s10457-005-7475-x.
Sunwar S, Thornstrom CG, Subedi A, Bystrom M: Home gardens in western Nepal: opportunities and challenges for on-farm management of agrobiodiversity. Biodivers Conserv. 2006, 15: 4211-4238. 10.1007/s10531-005-3576-0.
Drescher AW, Hagmann J, Chuma E: Homegardens a neglected potential for food security and sustainable land management in the communal lands of Zimbabwe. Der Tropenlandwirt Beitrge zur tropischen Landwirtschaft und Veterinrmedizin (Journal of Agriculture in the Tropics and Subtropics). 1999, 100: 163-180.
Vogl CR, Vogl-Lukasser B: Tradition, dynamics and sustainability of plant species composition and management in homegardens on organic and non-organic small scale farms in Alpine Eastern Tyrol. Austria. Biol Agric Hortic. 2003, 21: 149-166.
Reyes-Garca V, Aceituno L, Vila S, Calvet-Mir L, Garnatje T, Jesch A, Lastra JJ, Parada M, Rigat M, Valls J, Pardo-De Santayana M: Home gardens in three mountain regions of the Iberian peninsula: description, motivation for gardening, and gross financial benefits. J Sustain Agric. 2012, 36: 249-270. 10.1080/10440046.2011.627987.
Calvet-Mir L, Calvet-Mir M, Vaqu-Nuez L, Reyes-Garca V: Landraces in situ conservation: A case study in high-mountain home gardens in VallFosca, Catalan Pyrenees, Iberian Peninsula. Econ Bot. 2011, 65: 146-157. 10.1007/s12231-011-9156-1.
Bleasdale T, Crouch C, Harlan SL: Community gardening in disadvantaged neighborhoods in Phoenix, Arizona: Aligning programs with perceptions. Journal of Agric, Food Syst Community Dev. 2010-2011, 3 (1): 99-114.
Christanty L, Abdoellah OL, Marten GG, Iskandar J: Traditional agroforestry in West Java: the Pekaranagan (home garden) and Kebun-Talun (annual-perennial rotation) cropping systems. Traditional Agriculture in South East Asia. Edited by: Marten GG. 1986, Boulder CO, USA: Westview Press
Wiersum KF: Diversity and change in homegarden cultivation in Indonesia. Tropical Homegardens: A Time-Tested Example of Sustainable Agroforestry. Vol 3. Edited by: Nair BMKPKR. 2006, Dordrecht, The Netherlands: Springer Science
Meertens HCC, Fresco LO, Stoop WA: Farming systems dynamics: Impact of increasing population density and the availability of land resources on changes in agricultural systems. The case of Sukumaland, Tanzania. Agric Ecosys and Environ. 1996, 56: 203-215. 10.1016/0167-8809(95)00639-7.
Alam M: Tropical homegardens in Bangladesh: characteristics and sustainability. Sustainable Agriculture Reviews 6: Alternative Farming Systems, Biotechnology, Drought Stress and Ecological Fertilisation. Edited by: Lichtfouse E. 2011, Dordrecht, The Netherlands: Springer Science
Coomes OT, Ban N: Cultivated plant species diversity in home gardens of an Amazonian peasant village in northeastern Peru. Econ Bot. 2004, 58 (3): 420-434. 10.1663/0013-0001(2004)058[0420:CPSDIH]2.0.CO;2.
Bennett-Lartey SO, Ayernor GS, Markwei CM, Asante IK, Abbiw DK, Boateng SK, Anchirinah VM, Ekpe P: Contribution of Home Gardens to in situ Conservation of Plant Genetic Resources in Farming Systems in Ghana. 2002, Witzenhausen, Germany: Paper presented at Proceedings of the Second International Home Gardens Workshop
Soemarwoto O: Homegardens: a traditional agroforestry system with a promising future. Agroforestry: A Decade of Development. Edited by: Steppler H, Nair PKR. 1987, Nairobi, Kenya: International Council for Research in Agroforestry
Ali MY, Ahmed MM, Islam MB: Homestead Vegetable Gardening: Meeting the Need of Year Round Vegetable Requirement of Farm Family. 2008, Dhaka, Bangladesh: Paper presented at the National workshop on Multiple cropping
Talukder A, Kiess L, Huq N, de Pee S, Darnton-Hill I, Bloem MW: Increasing the production and consumption of vitamin Arich fruits and vegetables: lessons learned in taking the Bangladesh homestead gardening programme to a national scale. Food Nutr Bull. 2000, 21 (2): 165-172.
Abdoellah OS, Gunawan B, Hadikusumah HY: Home Gardens in the Upper Citarum Watershed, West Java: A Challenge for in situ Conservation of Plant Genetic Resources. 2001, Witzenhausen, Germany: Paper presented at Proceedings of the Second International Home Gardens Workshop
Pulami RP, Poudel D: Home Gardens Contribution to Livelihoods of Nepalese Farmers. 2006, Pokhara, Nepal: Paper presented at Home Gardens in Nepal: Proceeding of a workshop on Enhancing the contribution of home garden to on-farm management of plant genetic resources and to improve the livelihoods of Nepalese farmers: Lessons learned and policy implications (2004)
Alvarez-Buylla Roces ME, Lazos Chavero E, Garca-Barrios JR: Homegardens of a humid tropical region in Southeast Mexico: an example of an agroforestry cropping system in a recently established community. Agrofor Syst. 1989, 8: 133-156. 10.1007/BF00123117.
Abebe T, Wiersum K, Bongers F, Sterck F: Diversity and dynamics in homegardens of southern Ethiopia. Tropical Homegardens: A Time-tested Example of Sustainable Agroforestry. Edited by: Nair BMKPKR. 2006, Dordrecht, The Netherlands: Springer Science
von Grebmer K, Torero M, Olofinbiyi T, Fritschel T, Wiesmann D, Yohannes Y, Schofield L, von Oppeln C: The 2011 Global Hunger Index. 2011, Bonn, Germany; Washington DC, USA; Dublin, Ireland: International Food Policy Research Institute, Concern Worldwide, and Welthungerhilfe
Iannotti L, Cunningham K, Ruel M: Improving Diet Quality and Micronutrient Nutrition: Homestead Food Production in Bangladesh. 2009, Discussion Paper 00928, Washington DC, USA: International Food Policy Research Institute
Helen Keller International - Asia-Pacific: Homestead food production model contributes to improved household food security, nutrition and female empowerment experience from scaling-up programs in Asia (Bangladesh, Cambodia, Nepal and Philippines). Nutr Bull. 2010, 8 (1): 1-8.
Rao MR, Rajeswara Rao BR: Medicinal plants in tropical homegardens. Tropical Homegardens: A Time-tested Example of Sustainable Agroforestry. Edited by: Kumar BM, Nair PKR. 2006, Dordrecht, The Netherlands: Springer Science
Stoltzfus R, Mullany L, Black R: Iron deficiency anaemia. Comparative Quantification of Health Risks: Global and Regional Burden of Disease Attributable to Selected Major Risk Factors. Edited by: Ezzati M, Lopez A, Rodgers A, Murray C. 2004, Geneva, Switzerland: World Health Organization
Black R, Allen L, Bhutta Z, Caulfield L, de Onis M, Ezzati M, Mathers C, Rivera J: Maternal and child undernutrition: global and regional exposures and health consequences. Lancet. 2008, 371 (9608): 243-260.
Talukder A, Sapkota G, Shrestha S, de Pee S, Bloem MW: Homestead Food Production Program in Central and Far-Western Nepal Increases Food and Nutrition Security: An Overview of Program Achievements. 2006, Pokhara, Nepal: Paper presented at Home Gardens in Nepal: Proceeding of a workshop on Enhancing the contribution of home garden to on-farm management of plant genetic resources and to improve the livelihoods of Nepalese farmers: Lessons learned and policy implications (2004)
Keys E, Kaqchikel G: Women, Children, and Multiple Roles of Gardens among the Maya of Highland Guatemala. Yearbook, Conference of Latin Americanist Geographers. 1999, Austin TX, USA: Paper presented at Conference of Latin Americanist Geographers
Howard PL: Gender and social dynamics in swidden and homegardens in Latin America. Tropical Homegardens: A Time-Tested Example of Sustainable Agroforestry. Edited by: Nair BMKPKR. 2006, Heidelberg, The Netherlands: Springer Science
Kumar SK: Role of the Household Economy in Child Nutrition at Low Incomes: A Case Study in Kerala. 1978, Occasional Paper No. 95, Ithaca NY, USA: Department of Agricultural Economics, Cornell University
Adhikari A, Singh D, Suwal R, Shrestha PK, Gautam R: The Role of Gender in the Home Garden Management and Benefit-Sharing from Home Gardens in Different Production System of Nepal. 2006, Pokhara, Nepal: Paper presented at Home Gardens in Nepal: Proceeding of a workshop on Enhancing the contribution of home garden to on-farm management of plant genetic resources and to improve the livelihoods of Nepalese farmers: Lessons learned and policy implications (2004)
Soemarwoto O: The Javanese rural ecosystem. An Introduction to Human Ecology Research on Agricultural Systems in Southeast Asia. Edited by: Rambo AT, Sajise PE. 1984, Los Banos, The Philippines: University of Philippines
Blanckaert I, Swennen RL, Paredes Flores M, Rosas Lpez R, Lira SR: Floristic composition, plant uses and management practices in homegardens of San Rafael Coxcatln. Valle de Tehuacn-Cuicatln, Mxico. J Arid Environ. 2004, 57: 39-62.
Trinh LN, Watson JW, Hue NN, De NN, Minh NV, Chu P, Sthapit BR, Eyzaguirre PB: Agrobiodiversity conservation and development in Vietnamese home gardens. Agric Ecosyst Environ. 2003, 97: 317-344. 10.1016/S0167-8809(02)00228-1.
Calvet-Mir L, Gmez-Bagetthun E, Reyes-Garca V: Beyond food production: Home gardens ecosystem services. A case study in Vall Fosca, Catalan Pyrenees, northeastern Spain. Ecol Econ. 2012, 74: 153-160.
Pushpakumara DKNG, Wijesekara A, Hunter DG: Kandyan homegardens: A promising land management system in Sri Lanka. Sustainable use of Biological Diversity in Socio-ecological Production Landscapes. Background to the Satoyama Initiative for the Benefit of Biodiversity and Human Well-being. Edited by: Blair C, Ichikawa K, Wong BYL, Mulongoy KJ. 2010, Montreal, Canada: The Secretariat of the Convention on Biological Diversity
Powell JM, Williams TO: Livestock, Nutrient Cycling and Sustainable Agriculture in the West African Sahel. 1993, Gatekeeper Series No. 37, London, UK: International Institute for Environment and Development
Pushkaran K: Home Gardens in Kerala as an Efficient Agroecosystem for Conservation and Sustainable Management of Biodiversity. 2002, Witzenhausen, Germany: Paper presented at Proceedings of the Second International Home Gardens Workshop: Contributions of home gardens to in situ conservation of plant genetic resources in farming systems
Evers G, Keleta E, Kirway T: A farming system study in the lowland wet zone of Sri Lanka, Agalawatta Division, Kalutara District. 1985, Wageningen, The Netherlands: International Course for development oriented Research in Agriculture
United States Department of Agriculture: Definitions of Food Security.: Definitions of Food Security. http://www.ers.usda.gov/topics/food-nutrition-assistance/food-security-in-the-us/measurement.aspx (accessed January 2013)
Gasser M, Salzano C, Meglio RD, Lazarte-Hoyle A: Post-crisis Situations: Problems and Needs. Local Economic Development In Post-Crisis Situations: Operational Guide. 2004, International Labour Organization: Geneva, Switzerland
DHG initiated this review, conducted the bibliographic analysis, and developed the content of this manuscript. RF and KMM contributed to the enhancement of the framework and writing. All authors reviewed and approved the manuscript.
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Galhena, D.H., Freed, R. & Maredia, K.M. Home gardens: a promising approach to enhance household food security and wellbeing. Agric & Food Secur 2, 8 (2013). https://doi.org/10.1186/2048-7010-2-8
By using this website, you agree to our Terms and Conditions, California Privacy Statement, Privacy statement and Cookies policy. Manage cookies/Do not sell my data we use in the preference centre.
Because the garbage in the landfill is piled outside for a long time, it is easy to breed mosquitoes and flies, spread germs, and produce odor. Garbage is piled outside for a long time. Due to rain and other factors, there is running water. The garbage is wet and decomposes sewage leachate. The sewage causes pollution and great harm to the surrounding environment and residents. The main ...
OTT HydroMet introduces AQUARIUS - the analytics software that combines data simplicity and efficient reporting for water information. Hear from experts who are helping streamline the production and management of providing timely, accurate water data. Meet: Business Development Manager, Ihno Ihnen, OTT HydroMet Rnn Maiti , Regional Sales Manager, Aquatic ...
To meet the demand for food from a growing global population, aquaculture production is under great pressure to increase as capture fisheries have stagnated. However, aquaculture has raised a range of environmental concerns, and further increases in aquaculture production will face widespread environmental challenges. The effects of climate change will pose a further threat to global aquaculture production. Aquaculture is often at risk from a combination of climatic variables, including cyclone, drought, flood, global warming, ocean acidification, rainfall variation, salinity, and sea level rise. For aquaculture growth to be sustainable its environmental impacts must reduce significantly. Adaptation to climate change is also needed to produce more fish without environmental impacts. Some adaptation strategies including integrated aquaculture, recirculating aquaculture systems (RAS), and the expansion of seafood farming could increase aquaculture productivity, environmental sustainability, and climate change adaptability.
Aquaculture is practiced in three different water environments: (1) freshwater, (2) brackish water, and (3) seawater. Regardless of water environments, aquaculture can be divided into: (1) single species monoculture, (2) multiple species polyculture, and (3) integrated aquaculture with agriculture. Based on culture intensity as well as farming inputs (seed, feed, and fertilizer), aquaculture can be classified into: (1) extensive, (2) semi-intensive, and (3) intensive.
After being the most traded product in fish for decades, shrimp now ranks second in terms of value after salmon (including trout), whereas carp is the most dominant group of aquaculture fish in terms of volume (FAO 2018a).
Fish oil is extracted from fish while producing fishmeal. To prepare aquafeeds, the demand of fish oil is lower than fishmeal as only a few species require fish oil. The fish oil is a good source of nutrition, which provides of a smell to the feed (Robb et al. 2017).
Ahmed N, Bunting SW, Rahman S et al. (2014) Community-based climate change adaptation strategies for integrated prawn-fish-rice farming in Bangladesh to promote social-ecological resilience. Rev Aquac 6:2035
Barange M, Perry RI (2009) Physical and ecological impacts of climate change relevant to marine and inland capture fisheries and aquaculture. In: Cochraneo K, De Young C, Soto D et al. (eds) Climate Change Implications for Fisheries and Aquaculture: Overview of Current Scientific Knowledge. FAO Fisheries and Aquaculture Technical Paper No. 530. Rome, pp 7106
Boonyawiwat V, Patanasatienkul T, Kasornchandra J et al. (2017) Impact of farm management on expression of early mortality syndrome/acute hepatopancreatic necrosis disease (EMS/AHPND) on penaeid shrimp farms in Thailand. J Fish Dis 40:649659
Bregnballe J (2015) A guide to recirculation aquaculture: an introduction to the new environmentally friendly and highly productive closed fish farming systems. FAO and EUROFISH International Organization, Copenhagen
Chopin T, Cooper JA, Reid G et al. (2012) Open-water integrated multi-trophic aquaculture: environmental biomitigation and economic diversification of feed aquaculture by extractive aquaculture. Rev Aquac 4:209220
Church JA, Clark PU, Cazenave A et al. (2013) Sea level change. In: Stocker TF, Qin D, Plattner G-K et al. (eds) Climate Change 2013: The Physical Science Basis. Cambridge University Press, Cambridge, UK, pp 11371216
De Silva SS, Soto D (2009) Climate change and aquaculture: potential impacts, adaptation and mitigation. In: Cochrane K, De Young C, Soto D et al. (eds) Climate Change Implications for Fisheries and Aquaculture: Overview of Current Scientific Knowledge. FAO Fisheries and Aquaculture Technical Paper No. 530, Rome, pp 151212
Duncan C, Primavera JH, Pettorelli N et al. (2016) Rehabilitating mangrove ecosystem services: a case study on the relative benefits of abandoned pond reversion from Panay Island, Philippines. Mar Pollut Bull 109:772782
Klamt A-M, Schernewski G (2013) Climate change a new opportunity for mussel farming in the southern Baltic? In: Schmidt-Thom P, Klein J (eds), Climate Change Adaptation in Practice: From Strategy Development to Implementation. John Wiley & Sons Ltd, New Jersey, pp 171184
Miao W, Yuan X (2007) The carp farming industry in China an overview. In: Leung PS, Lee C-S, OBryen PJ (eds), Species and System Selection for Sustainable Aquaculture. Blackwell Publishing, Oxford, pp 373388
NACA (2012) Vulnerability and Adaptation to Climate Change for Improved Polyculture Farming Systems in the Mekong Delta, Viet Nam Case Study Report. Network of Aquaculture Centres in Asia-Pacific, Bangkok
Nguyen AL, Dang VH, Bosma RH et al. (2014) Simulated impacts of climate change on current farming locations of striped catfish (Pangasianodon hypophthalmus; Sauvage) in the Mekong Delta, Vietnam. Ambio 43:10591068
Nhan DK, Phong LT, Verdegem MJC et al. (2007) Integrated freshwater aquaculture, crop and livestock production in the Mekong delta, Vietnam: determinants and the role of the pond. Agric Syst 94:445458
Nicholls RJ, Wong PP, Burkett VR et al. (2007) Coastal systems and low-lying areas. In: Parry ML, Canziani OF, Palutikof JP et al. (eds) Climate Change 2007: Impacts, Adaptation and Vulnerability. Cambridge University Press, Cambridge, UK, pp 315356
Primavera JH, Garcia LMB, Castaos MT et al. (eds) (2000) Mangrove-Friendly Aquaculture: Proceedings of the Workshop on Mangrove-Friendly Aquaculture. Organized by the SEAFDEC, Iloilo City, Philippines
Siikamki J, Sanchirico JN, Jardine S et al. (2012) Blue Carbon: Global Options for Reducing Emissions from the Degradation and Development of Coastal Ecosystems. Resources for the Future, Washington DC
Sweet WV, Horton R, Kopp RE et al. (2017) Sea level rise. In: Wuebbles DJ, Fahey DW, Hibbard KA et al. (eds) Climate Science Special Report: Fourth National Climate Assessment. U.S. Global Change Research Program, Washington DC, pp 333363
The study was supported through the Alexander von Humboldt Foundation, Germany. The study was a part of the first authors research work under the Georg Forster Research Fellowship by the Alexander von Humboldt Foundation at the Leibniz Center for Tropical Marine Research (ZMT) in Bremen, Germany. The study was also linked to the first authors research at the Natural Resources Institute (NRI), University of Manitoba, Canada. An earlier draft of this paper was presented in March 2017 by the first author at the ZMT, Germany. We thank the audience for their positive encouragement. The views and opinions expressed herein are solely those of the authors and do not necessarily reflect the views of ZMT or NRI. We thank two anonymous reviewers for insightful comments.
Ahmed, N., Thompson, S. & Glaser, M. Global Aquaculture Productivity, Environmental Sustainability, and Climate Change Adaptability. Environmental Management 63, 159172 (2019). https://doi.org/10.1007/s00267-018-1117-3
We are the leading manufacturers of textile accessories and garments in Pakistan. specialize a wide range identification products for garments. From raw material to finished goods, we provide complete production under one roof Our 35 years excellence is based on truth, sincerity, hard work & ...
JAKIFLOW is an industrial leader in developing and manufacturing butterfly valves sleeved plug valves, manual control operated for diverse applications focused on the Water Treatment, Petrochemical, Desalination, Chemical Processing industries. JAKIFLOWs advanced provide ideal ...
GEA Solutions is a fast growing firm bearing motto in mind for better quality which starts its journey at 2017. The was configured with some dynamic and potential engineers having high quality performance, good reputation strong ability of liaison. Capability understanding ...
Our company The strength of our high quality the item is to supply most competitive prices. We are in cases same or similar items will be gonggeuphalsu much more Moreover, special needs your organization may present a new design for ...
I\\\'m Lois from Goldragon Manufacturing Industry Co., Ltd. We are a professional manufacturer of CV joints & drive shaft.We have own metal processing, assembling, welding, tempering, painting workshops with advance machines and skilled workers. Hope to be your supplier joint. ...
Clipping Path Group provides fast, cheap and excellent online photo editing services like- Remove Background From Image, Photoshop Services, Image Cutout Service, E-commerce Product Photo Editing, Ghost Mannequin, masking, Shadow Creation, Professional Retouching, Color Correction & ...
Tueling staal fze is a one of the most project package specialist for distribution steel Nuts & bolts ,Pipes, fittings and other piping components used in fluid gas transmission all over world with best price guaranteed satisfied customers ...
Beijing Silk Road Enterprise Management Services Co.,LTD is one of the dealers & exporters brand CATERPILLAR SEM new construction equipments in China, we export Caterpillar machinery including excavator, wheel loader, bulldozer, motor grader, road roller etc. ...
BitsnPixs, based in Georgia, United States has been offering the best digitizing artwork for embroidery and vector conversion since 2012 with thousands of satisfied customers worldwide, which helped it earn a premier position industry. BitsnPixs is one services USA. We have diverse highly ...
Oriental Ocean Tech. aim to support offshore companies explore ocean sources by providing reliable and environmentally friendly deepwater buoy pressure resistance AUV bodies. We have different buoys like ROV buoys, cable floats, customized for wind farms. Our characters of low density high ...
Kosa Environmental Protection Co., Ltd.is a high-tech enterprise specializing in R&D,design,manufacture,sales and service of dust filtration liquid filtration.The main products are high temperature filter bag,filter cage collector equipment;bag filter,filter element, micron ...
We, Apple Food Industries from 1993 are manufacturing, wholesaling and exporting a high-quality range of Dehydrated Onion, Ginger Garlic. Offered products consists Garlic, Ginger, Red Chilli, Beetroot Powder, Spray Dried Tomato Turmeric Moringa Leaves, Powder Hibascus Flower, Black ...
PRIMA Automation (India) Pvt. Ltd. is an ISO 9001:2015, EMS 14001:2015 and OHSAS 45001:2018 certified leading manufacturer of Industrial Control Panels Solution Provider in the State Gujarat, INDIA. has integrated facility having all Department, like Sales, Marketing, Engineering, ...
Leftover garments is a Pakistani enterprises selling brand new garments, paints, shirts, jeans, formal dresses, trousers, undergarments, ladies suitings & gents suitings. We are also preparing leftover clothes for export purpose and on the other hand we prepare all types of in referesh form ...
Turbo Intex Co Ltd., was established in 2002 workplace based Bangkok, Thailand. Co., is a foreign trade company which understood by its name and deals with import export general. Our has primarily focused on manufacturing of Autospares parts products it many years experience. A leading ...
EESINT, a multi-national company, has proven itself to be dynamic and progressive enterprise, positioning as one of the leading quality industrial solution provider company since 2011. EESINT provides competitive Industrial Power, Automation & Instrumentation Solution Services Process ...
We are a sourcing agent, manufacturer and exporter with offices in Sydney, Australia Dhaka, Bangladesh. Our expertise experience come from years of hard work many our esteemed clients helping their brands grow. take pride commitment strategy to deliver outcomes that bring results for ...
Being a professional enterprise, we have the first-class working team---the specialized designers ,excellent international trading managers, and high technical production facility with 27000 square meters of base, exporting ability up to 70*40HQ each month. gained global sales network ...
For over five generations, Standard Tile has set the standard for tile stores in product line, knowledge, service, and design expertise. We maintain our leadership with establishment of beautiful showrooms containing wide variety products. ...
CFS Foundry is the professional stainless steel investment casting company in China. We can customize parts from our client\\\'s drawing or sample. Currently, most typical industries served include: Automotive, food machinery, marine, architecture, etc. serve: 304(L) 316(L) 17-4 ph 2205 ...
Only specialized in Garments Stocks for 18 Years In China, Cheap Price, Immediate Shipment, always provide all kinds of garments stocks competitive price and good quality. We have All including casual wear, sports underwear, fashion wearfor Men, Lady, Boy, Girl, Baby Own a professional ...
Advice that carrier sends to consignee advising of goods coming forward for delivery. Pertinent information such as BL number, container number and total charges due from consignee, etc are included and sent to consignee prior to vessel arrival. This is done gratuitously by carrier to ensure smooth delivery but there is no obligation bycarrier to do so and the responsibility to monitortransit and present himself to take timely delivery still rest with the consignee.
A facility or consolidation centre that is authorized by customs to store goods, usually separately on dutiable & non-dutiable goods, pending customs inspection and clearance. The goods in it are secured under customs custody. The payment of duties and taxes are only payable once the goods are removed.
Also known as Custom Broker. A person or firm, licensed to engage in entering and clearing goods through customs and/or the government office (Custom house) where duties and/or tolls are placed on imports or exports. The duties of a broker include preparing the entry blank and filing it; advising the importer on duties to be paid; advancing duties and other costs; and, arranging for delivery to his client, his trucking firm, or other carrier.
One of 13 INCOTERMS."Free Carrier" means that the seller delivers the goods, cleared for export, to the carrier nominated by the buyer at the named place. It should be noted that the chosen place of delivery has an impact on the obligations of loading and unloading the goods at that place. If delivery occurs at the seller's premises, the seller is responsible for loading. If delivery occurs at any other place, the seller is not responsible for unloading.
Known also as Freight Forwarder, Foreign Freight Forwarder. Its an individual or business that dispatches shipments by land, air, or sea, or it may specialize for exporters and for a fee. Usually it handles all the services in the collection, consolidation, shipping and distribution of goods connected with an export shipment; preparation of documents, booking cargo space, warehouse, pier delivery and export clearance. The firm may also handle banking and insurance services on behalf of a client.
In the industry, it is the generic name for a temperature controlled container. The containers, which are insulated, are specially designed to allow temperature controlled air circulated within the container. A refrigeration plant is built into the rear of the container. For OOCL's reefers, power for this plant needs to be provided from an external source. Related topics:- See also Genset.- See also PTI.
The person for whom the owners of a ship agree to carry goods to a specified destination and at a specified price. The merchant who can be consignor, exporter, or seller (who may be the same or different parties) named in the shipping documents as the party responsible for initiating a shipment, and who may also bear the freight cost.'
High Quality Carbon Black Briquette Ball Press Machine. High Quality Silicate Hammer Crusher Sell At A Loss In . High Quality Silicate Hammer Crusher Sell At A Loss In Ismailia Egypt Africa.Ismailia Egypt Africa Tangible Benefits Large Rock Impact Crusher For Salemineral Powder Briquetting Machine Is Mainly Used For Pressing Nonferrous And Ferrous Metal Powder Such As Iron Phosphate Rock ...
If you have any problems or questions about our products or need our support and assistance, please contact us and you will be replied within 24 hours. We promise we will never reveal your information to the third party. Thank you!
Briquette Machine Economic New Soft Rock Briquetting. Economicnew Soft Rockbriquetting Machinefor Sale In Leeds. Warri Nigeria Africa New Soft Rock Ore Concentrate Sell Atwarri Nigeria Africa New Soft Rock Ore Concentrate Sell Atwarri Nigeria Africa New Soft Rock Ore Concentrate Sell At A Loss New Talc Dryermachinein Patan Nepal South Asia Small Rock Chinaware Ball Mill In Leeds Britain Europe ...
Limestone Briquetting Machine In Malaysia. Granite Rock Breaking Machine Manufacturer In Malaysia With One 100000Sqft Factory Equipped With 2 Gangsaws 1 Block Cutter 2 Polishing Lines 1 UV Line Epoxy And Impregnator Sectors We Can Manufacture 3000Tons Of Slabs Monthly Two Separate Factories With 4 Cutters And Profiling Machines We Are One Of The Biggest Manufacturers Of Dimensional Stone ...
Abadan High Quality Limestone Briquetting Machine Sell At A Loss Abadaniran West Asiahighend Medium Lump Coal Dryermachinefor Sale.Highendnew Bentonite Gold Ore Separating Linesell At A Lossinabadan Iran West Asia.West Asia Highqualitymediumbentonite Bucket Conveyersellat A Lossmillenium Papers Pvt Ltd A Unit Of Koradiya Group Of Companies Is A ...
How To Distinguish Coal Briquetting Machine And. Tangible Benefits New Iron Ore Ore Concentrate Sell It. Tangible Benefits New Iron Ore Ore Concentrate Sell It At A Bargain Price In Amman Jordan West Asia. Aba High End Rock Briquetting Machine Sell At A Loss We Have West Asia High End Calcining Ore Ore Concentrate For Saleiron Ore Is The Raw Material Used To Make Pig Iron Which Is One Of The ...
Feldspar High Quality Small Briquette Machine For Sale. Feldspar High Quality Small Briquette Machine For Sale. High Quality Small Pottery Feldspar Chute Feeder Sell In Tangible Benefits Potash Feldspar Briquetting Machine Sell High Quality Salt Briquetting Machine For Sale In South Asia Low Price Chrome Ore Briquetting Machine Sell It At A Bargain Price In Namibia Large Pyrrhotite Briquetting ...
We Are A Professional Mining Machinery Manufacturer, The Main Equipment Including Jaw Crusher, Cone Crusher And Other Sandstone Equipmentball Mill, Flotation Machine, Concentrator And Other Beneficiation Equipment Powder Grinding Plant, Rotary Dryer, Briquette Machine, Mining, Metallurgy And Other Related Equipment. Which Can Crush All Kinds Of Metal And Non-Metallic Ore, Also Can Be Dry ...
Manufacturers Of Biomass Briquette Machines Ecostan. Aug 04, Process The Dried And Granulated Raw-Material Is Fed Into The Machine With The Help Of In-Feed Screw Conveyor. Further, The Material Enters Into The Machine Keep, The Keep Worm Pushes The Material Into The Briquetting Chamber. The Biofuel Briquettes Are Formed In The Briquetting Chamber Without The Need Of Any Binder With High ...
Briquette Machine Hot Products Basalt River Gravel And Other Kinds Of Rock Stone Materials Are Primarily Crushed By The Jaw Crusher And Then The Coarse Products Are Transported To Fine Crusher By The Belt Conveyor For Further Crushing T H Coal Rock Stone Production Line Hammer Hsm Ce Iso Good Quality Stone Rock Crushing Machine Hsm Iso ...
Briquetting Machineproject List - Top Project Machinery. We Have Briquetting Machine,Tangible Benefits Small River Sand Dust Catcher Price In Tangible Benefitssmall Quartz Briquetting Machineprice.Tangible Benefitssmall Quartz Briquetting Machine Pricesmall Refractory Material Briquetting Machinein South Africajul 12 2017 The Two Main Types Of Briquettes On The Market In SA Today Is ...
We Have Soft Rock Briquette Making Machine In Jakarta ,Jakarta Portable Soft Rock Wood Pellet Making Machinesell 200500Kghhammer Millforwood Pelletmaterial Theelectric Hammer Mill Poweris 75Kw Capacity Is 200500Kgh Suitable Formaking Wood Pellet Stove Pelletsfor Your Own Family 2 Both Coarse And Fine Grinding Can Be Realized Through Adjusting The Gap Between Hammers And Screen Get Price...
Mar 15, 2019 Fine Sand Briquetting Machine In Chile. Medium Cement Clinker Sand Washer In Iquique Chile South America Iquique Chile South Americahigh Qualitymediumbarite Dust Catcher For Sale Barite Crushing And Grinding Equipment For Barite Quarry Or Mining Its Better To Choose Hammer Crusher And Impact Crusher The Reduction Ratio Of These Barite Crushers Are Generally 1035 Jaw Barite Crusher Is
Efficientlarge Basalt Dryermachine Sellat A Loss In. Efficient Large Basalt Dryer Machine Sell At A Loss In Harper London Britaineurope Tangible Benefitssilicate Shaking Table For Saletangible Benefitssmall Silicate Ore Concentrate Sell It At A Bargain Price In Britain Europeaba High End Rock Briquetting Machine Sell At A Loss We Have West Asia High End Calcining Ore Ore Concentrate For
Crusher Machine For Sale In The Philippines Crusher Machine For Sale Is The Mechanical Equipment Used To Crush Minerals Generally, A Crushing Machine Can Crush Different Materials, Such As River Pebbles, Granite, Limestone, Basalt, Ore, Rock, Stone, Gypsum, Coal, Etcaccording To The Feed Particle Size And Discharge Size, The Process Of Crushing Includes Three Stages, Coarse Crushing
Briquette Machinestate Of Penang Tangible Benefits Medium. Pattaya Thailand Southeast Asia Small Gypsum Sand Washerpattaya Thailand Southeast Asia Small Gypsum Sand Washerstate Of Penang Malaysiasoutheast Asiatangible Benefits Medium Limestone Rotary Kiln Sellstate Of Penang High Quality Rock Briquetting Machine Sell At A Loss Tirana Medium Bauxite Briquetting Machine Sell It At A
Apr 13, 2021 The Cheapest Limestone Rock Briquetting Manufacturer In Philippines. Briquette Machine 10 Tph Iron Ore Powder Biomass Briquette Press For Sale In Netherlands. 10 Tph Marble Powder Briquetting Manufacturer Briquetting Machinefor Sale Competitiveprice Many Fotebriquetting Machinecases Fote Is A Manufacturerof Briquetting Machineswith Professional Rd Engineers And
Small Soft Rock Briquetting Machine In Abuja. Low Price Smallgangue Briquetting Machine In Abujacharcoalbriquettepress Sawdustbriquette Machinebiofuelbriquettemill Manufacturer Supplier In China Offering High Output Low Price Sawdustbriquette Making Machinefor Sale Russia Use Small Waste Paper Pelletmachinewood Paper Pelletmaking Machine8001000kgh Wood Sawdust Pellet Mill
Large Iron Ore Briquetting Machine In Daejeon. Efficient Environmental Diabase Briquetting Machine For Sale In Daejeon The Highefficiency Concentrator Produced By Our Company Is Suitable For Dehydrating The Ore Concentration And Tailings Classifier Argentina High Qualityenvironmental Diabase Briquette Large River Pebble Dust Catcher In Cordobaargentinasouth Jaw
Bangkok Tangible Benefits Medium Rock Briquette Making Machine For Sale Mediumsandstone Mobilecrusherin Bauchinigeriaafrica. We Havemediumriver Sand Sand Maker In Bauchinigeriaafricasand Brick Making Machine Is To Produce Sand Bricks As For Raw Materials You Can Choose From The Fly Ash River Sand Slag And Other Construction Waste Before Molding ...
Suva Economic Portable River Pebble Briquette Making Machine Sell It At A Bargain Price. Economic New River Pebble Briquette Making Machine Sell At A Loss In New Delhi Hydraulicbriquetting Machineyukebriquette Machine High Qualitynew River Pebblecoal Millsell At A Lossin Hydraulic Hot Press Smallbriquette Makingmachinerice Pulverized Coalbriquetting Machineis The Equipment Which Mixes
Coal Briquetting History Acan Machine. Briquetting Peat With Air And Gas Drying Is Carried Out Under The Scheme Classification And Segmentation In Some Cases Of Incoming Raw Materials To A Size Of Less Than 610 Mm Drying Flue Gases In The Air And Gas Dryer Tube-Dryer, A Dryer With A Fan Or Shaft Grinding Mill The Capture Of Dry Peat In The Cyclone, Pressed At A Pressure Of.
Sri Lanka New Scrap Iron Briquetting Machine Price Spot Sales ... Pebble Shaking Table Sell It At A Bargain Price In Ondorhaan Mongolia East Asia,Get Free 2Day Shipping On Qualified River Rock Landscape Rocks Products Or Buy Outdoors Department Products Today With Buy Online Pick Up In Store River Rock Landscape Rocks Hardscapes ...
Coke Powder Briquetting Press Machine Working Priciple . This Series Of Briquette Machine Will Pass The Power On To The Two Pressure Roller Through The Reducer.The Two Sides And Roll Rotat Ion, In Both The Rotating Roll,Natural Materials To Enter The Ball Ro Ll Mode, With The Roll Rotation, Material Pressure On A Small Becomeamp Amp Amp Nbsplarger, When The Material To The Two Rollers ...
High Density Briquetting Press Machine In South Africa. High Pressure Roller Briquetting Machine. High Pressure Briquette Machine,Briquetting Press 2019-8-20 It Has Become A Professional Plant Integrated Of Development, Research, Test, Design, Manufacturing And Service For High-Pressure Briquetting Machine In Domestic With The Most Perfect ...
Low Price Basalt Briquetting Machine Sell It At A Bargain Price In Walvis Bay Low Price River Sand Ball Mill Sell It At A Bargain Price In Veracruz Mexico North Americawith An Average Price Of 844904 The Combined Market Value Of Waterfront Property For Sale In Texas Was 2.
New Coal Face Briquetting Machine In Aswan Briquette Machine. Sandy Gravel Briquetting Machine In Spain. Sandy Gravel Briquetting Machine In Spain The Strong Briquetting Machine Is Mainly Used For Coal Powder Coal Clay Coke Coke Powder Refractory And Metallurgical Powder Cold Pressed Pellet Read More It Can Make A Variety Of Rock Sand And Gravel River Pebbles Into Various Size Construction ...
Jan 22, 2020 High Output Charcoal Dust Ball Press Machine. Homemade Hydraulic Sawdust Briquette Press Youtube. Briquette Press Machine And Sawdust Briquetting Plant For Sale.The Moisture Percentage Should Be Kept From 10 To 20.Through Feeding Conveyor, The Fragments Will Be Sent To Screw Feeder And Then Be Pushed Into The Inlet Of Briquette Press Machine.Then Fuel Briquettes Will Be Formed.Build A ...
Chrome Ore Briquette Machine Chrome Briquette Machine . Zhongzhou Chrome Ore Briquettebriquetting Machine Is A Roller Type Briquetting Equipment Which Used In Press Chrome Ore Briquettes, It Also Be Named Ball Press Machine. The Chrome Ore Briquettebriquetting Machine Can Press The Chrome Materials Which Blended With A Certain Amount Of Binder, The Final Briquettes Is About But
Machines That Make Gypsum Minerals. The Main Equipment Including Jaw Crusher, Cone ,Gypsum Grinding Plant In Egypt Quartz Drying Plant In Russia Zoneding Machine Is A Professional Manufacturer Of Mining Crushing Screening And Drying Equipments With A Longterm Supply Of Ore Dressing And Gravel Aggregate Industries With Crushers Vibrating Screens Washing Equipments And Belt We Are A
France Carbon Dust Briquette Machine. France Carbon Dust Briquette Machine. . Lime Briquette Machine In Tanzania. Dry Powder Briquette Machine Is Mainly Used To Make The Coal Powder Iron Powder Coke Aluminum Powder Scrap Iron Sinter Toner Carbon Dust Slag Gypsum Tailings Sludge Kaolin Activated Carbon Coke Breeze And Other Powders And Wastes Be Widely Used In Refractory Bbq .
Briquetting Machine For Sale In Russian Federation . Coal Slime Dryer For Sale In Russian Federation. China Russian Coal China Russian Coal Manufacturers And A Wide Variety Of Russian Coal Options Are Available To You, Such As Briquette You Can Also Choose From Briquette Machines As Well As From Hookah, Carrier Of Chemical Activator There Are Russian Coal Suppliers, Mainly Located In Asia
Anthracite Coal Briquetting Machine Used In Russia Mexico Brazil. The Briquetting Ratio Reaches Coal Dust Briquette Machine Is Also Called Coal Powder Molding Machine, It Is Used To Briquette Coal Powder, Coal Gangue, Soft Coal, Anthrocite Coal, Etc Belongs To Cold Briquetting Technology In Production, It Can Produce Popular Briquette Shapes, Like Oval Shape, Pillow Shape And Square Shape, Etc ...
Metal Powder Briquetting Machine. Sphere Size Custom-Made Raw Material Size 0-5Mm Production Capacity 2.2-50TPH Dry Powder Briquetting Machine. Power 37-55Kw Capacity 1-18TPH Application It Is Widely Used In Refractory Materials, Powder Plant, Metallurgy, Chemical Industry, Energy, Transportation, Heating And Other Industries. Aluminite Powder Briquetting Machine
Sharjah Tangible Benefits Environmental Pottery Feldspar ,Sharjah Tangible Benefits Environmental Pottery Feldspar Steel Ball Manufacturer Large Copper Mine Bucket Conveyer In Warri Nigeria Africa Magnetic Separator For Salein Phuket Thailand Southeast Asiasharjah Tangible Benefitsaluminum Hydroxide Briquetting Machine Pricethe List Of Top 100 Jobs Careers For 2018 2019 2020 Upcoming Years Is ...
High Quality Mediumbluestone Briquetting Machine In Monrovia. High Quality Mediumbluestone Briquetting Machine In Monrovia,Large Crushers Andbriquetting Machineour Pound Crusher Has Large Crushing Ratio And Highe Yield With 14 Times Yield Than Other Crushersit Has Efficient Crushing Capacity For Shale Glass Ceramics River Gravel Granite Basalt Iron Orebluestonemetal Ores And Other Hard ...
Jan 22, 2020 High Output Charcoal Dust Ball Press Machine. Homemade Hydraulic Sawdust Briquette Press Youtube. Briquette Press Machine And Sawdust Briquetting Plant For Sale.The Moisture Percentage Should Be Kept From 10 To 20.Through Feeding Conveyor, The Fragments Will Be Sent To Screw Feeder And Then Be Pushed Into The Inlet Of Briquette Press Machine.Then Fuel Briquettes Will Be Formed.Build A ...
Hcker Polytechnik Briquetting Press And Filter System. Sep 24 2020 Wheat Straw Briquetting Making Forming Machine Price In Agro Briquetting Plant System Bio Coal Fuel Machine. 65 Mm Small Size Briquetting Plants Are Small In Size Required Powder Form Of The Biomass Raw Material To Form 65 Mm Briquettes And Best Suited To The Buyers Who Have Small Firm Plan We Are The Renowned Manufacturer
Coal Slime Briquette Making Machine In China Induzin. China Coal Charocal Dust Briquette Briquetting Making. High Efficient Coal Briquette Machine Is An Equipment Which Can Press Variety Of Coal Powder Coal Dustcoal Slime Coking Coal Coke Powder Aluminum Powder Iron Powder Iron Scurf Iron Oxide Skin Active Carbon Slag Gypsum Limestone Plastic Kaolin And
Soil is the medium for plant growth and the substrate for all biogeochemical and biogeophysical processes. Soils unique natural organization forms the foundation of any foodwaterenergy nexus system. It forms a habitat for billions of diverse micro, meso, and macrofauna and flora and is the basis of numerous ecosystem services essential to human well-being and nature conservancy. It moderates soil hydrological processes within the entire vadose zone: which is part of the earth between the soil surface and the phreatic zone. Soil structure also supports numerous ecosystem services including nutrient transformation and availability, water quality and renewability, denaturing and transport of pollutants, and groundwater table fluctuations. It also moderates the soilwaterplant-energy nexus with the replenishement of green-water supply (from precipitation) for plants and soil biota, which in turn enables the production of biomass as a source of food, feed, fiber, and biofuel feedstock. Indeed, soil is a very large reservoir for water and carbon with strong influences on local, regional, and global climate. Also, the energy factor is connected with the climate change through soilwaterfoodenergy nexus because of numerous interlinked pathways including gaseous emissions, energy and food production, and recycling of nutrients and water at regional, national, and global scales. Through provisioning of numerous ecosystem services, the soilwaterfoodenergyclimate nexus is interwoven with the ecosystem security and functioning of planets four ecospheres (i.e., atmosphere, hydrosphere, lithosphere, and the biosphere). Therefore, the health of soil, plants, animals, people, and ecosystems is one and indivisible.
This interconnectivity is also the basis of the 4 per Thousand initiative adopted by the COP21, the Climate Summit of 2015 in Paris, and Adapting African Agriculture (AAA) by COP22 in Morocco. Consequently, soil is not only a foundation for securing the natural resources: food, water and energy, but it is under desperate need to be integrated and appreciated in understanding the complex interconnectedness of any food, energy, water and soil system. Concentration and stock of soil organic carbon are the key soil properties that determine the physical, chemical, biological, and ecological properties and processes, and are major control of all nexuses described herein.
This chapter presents a conceptual model and the role of soil as a naturally organized medium to protect global food, water, energy securities. Moreover, it elaborates on using soil as a basic nexus tool and proposes a paradigm shift in integrating soil and creating the foodenergywatersoil nexus.
The original version of this article, published in Current Sustainable Renewable Energy Reports, Volume 4, Issue 3, September 2017, inadvertently misspelled an authors last name on the title page as Haimanote Baybil. The correct name is Haimanote Bayabil.
Abel S, Peters A, Trinks S, Schonsky H, Facklam M, Wessolek G. Impact of biochar and hydrochar addition on water retention and water repellency of sandy soil. Geoderma. 2013;202-203:18391. doi:10.1016/j.geoderma.2013.03.003.
Asai H, Samson B, Stephan H, Songyikhangsuthor K, Homma K, Kiyono Y, et al. Biochar amendment techniques for upland rice production in northern Laos: soil physical properties, leaf SPAD and grain yield. Field Crops Res. 2009;111:814.
Assi AT, Accola J, Hovhannissian G, Mohtar RH, Braudeau E. Physics of soil medium organization, part 2: pedostructure characterization through measurement and modeling the soil moisture characteristic curves. Front Environ Sci. 2014;2:5. doi:10.3389/fenvs.2014.00005.
Elhaja, ME, Ibrahim, IS, Adam, HE, Csaplovics, E. (2014). Soil aggregate stability and wind erodible fraction in a semi-arid environment of White Nile State, Sudan. In: SPIE Asia Pacific Remote Sensing. International Society for Optics and Photonics; 926017-926017-5.
Grafton RQ, McLindin M, Hussey K, Wyrwoll P, Wichelns D, Ringler C, et al. Responding to global challenges in food, energy, environment and water: risks and options assessment for decision-making. Asia Pac Policy Stud. 2016;3(2):27599.
Hurni H, Giger M, Liniger H, Studer R, Messerli P, Portner B, et al. Soils, agriculture and food security: the interplay between ecosystem functioning and human well-being. Curr Opin Environ Sustain. 2015;15:2534.
Karhu K, Mattila T, Bergstrm I, Regina K. Biochar addition to agricultural soil increased CH4 uptake and water holding capacityresults from a short-term pilot field study. Agric Ecosyst Environ. 2011;140:30913. doi:10.1016/j.agee.2010.12.005.
Laird DA, Fleming P, Davis DD, Horton R, Wang B, Karlen DL. Impact of biochar amendments on the quality of a typical Midwestern agricultural soil. Geoderma. 2010;158:4439. doi:10.1016/j.geoderma.2010.05.013.
Lal R. Soil carbon sequestration impacts on global climate change and food security. Science. 2004b;304:16237. It is a seminal article on the importance of soil organic carbon to agronomic productivity and adaptation/mitigation of climate change.
Lal R. The nexus approach in managing water, soil and waste under changing climate and growing demands on natural resources. In: Kurian M, Ardakanian R, editors. Governing the nexus: water, soil, waste change. Dordrecht, Holland: Springer; 2015a. p. 3961.
Martin, D. (2016). At the nexus of fire, water and society. Philosophical Transactions of the Royal Society B-Biological Sciences 371, no 1696. It is important to understanding the conceptual basis of the nexus approach in addressing global issues.
McCarl, B.A., and J.M. Reilly. (2007). US Agriculture in the climate change squeeze: Part 1: Sectoral Sensitivity and Vulnerability, report to National Environmental Trust http://agecon2.tamu.edu/people/faculty/mccarl-bruce/papers/1303Agriculture in the climate change squeez1.doc.
Mohtar RH, Assi AT, Daher BT. Current water for food situational analysis in the Arab region and expected changes due to dynamic externalities. In: Water Security in a New World, Amer K, et al., editors. The Water, Energy, and Food Security Nexus in the Arab Region. New York: Springer; 2016. p. 193208.
Mohtar RH, Daher B. Water-energy-food nexus framework for facilitating multi-stakeholder dialogue. Water Int. 2016;41(5):65561. This article highlights the significance of nexus framework to facilitating multi-stakeholder dialogue.
Mohtar, R.H., Assi, A. T. and Daher, B. T. (2015). Bridging the water and food gap: the role of the water-energy-food nexus. UNUFLORES Working Paper Series 5, Edited by Hiroshan Hettiarachchi. Dresden: United Nations University Institute for Integrated Management of Material Fluxes and of Resources (UNU-FLORES).
Mohtar RH. An integrated sustainability index for effective water policy. In: Waughray D, editor. Water security: the water-food-energy-climate nexus world economic forum water initiative. Washington: Island Press; 2011. p. 271.
Pate, R., M. Hightower, C. Cemron, W. Einfeld. (2007). Overview of energy-water interdependencies and the emerging energy demands on water resources. Report SAND 2007-1349C. Los Alamos National Lab, NM.
Raper R, Schwab E, Balkcom K, Burmester C, Reeves D. Effect of annual, biennial, and triennial in-row subsoiling on soil compaction and cotton yield in southeastern US silt loam soils. Appl Eng Agric. 2005;21:33743.
Temesgen M, Savenije H, Rockstrm J, Hoogmoed W. Assessment of strip tillage systems for maize production in semi-arid Ethiopia: effects on grain yield, water balance and water productivity. Phys Chem Earth. 2012a;parts A/B/C 47:15665.
Temesgen M, Uhlenbrook S, Simane B, Zaag P, Mohamed Y, Wenninger J, et al. Impacts of conservation tillage on the hydrological and agronomic performance of Fanya juus in the upper Blue Nile (Abbay) river basin. Hydrol Earth Syst Sci. 2012b;16:472535.
Verheijen F, Jeffery S, Bastos AC, van der Velde M, Diafas I. Biochar application to soilsa critical scientific review of effects on soil properties, processes and functions (EUR 24099 EN). Luxembourg: Office for the Official Publications of the European Communities; 2009.
Wada Y, Florke M, Hanasaki N, Eisner S, Fischer G, Tramberend S, et al. Modeling global water use for the 21st century: the water futures and solutions (wfas) initiative and its approaches. Geosci Model Dev. 2016;9(1):175222.
Lal, R., Mohtar, R.H., Assi, A.T. et al. Soil as a Basic Nexus Tool: Soils at the Center of the FoodEnergyWater Nexus. Curr Sustainable Renewable Energy Rep 4, 117129 (2017). https://doi.org/10.1007/s40518-017-0082-4
Innovative processes aimed at sustainable development or eco-innovations have received increasing attention during the past years despite the lack of theoretical and methodological approaches to analyzing their impact. This paper focuses on how sustainability indicators can be used to measure the effects of non-technical eco-innovations in the Sri Lankan tea plantation sector. After carrying out an experimental case study on a commercial tea plantation, we employed a combination of physical and monetary sustainability indicators to evaluate the initial results of the eco-innovation. It shows that innovations aimed at improving economic benefits often result in unintentional environmental and social benefits that support a lean-green relationship. It reveals the difficulty in having a standardized set of indicators to measure the impact of eco-innovations owing to the multidimensionality of sustainability. Hence, the case study suggests adopting broad sustainability indicators that represent the wholeness of the system while capturing the long-term impact.
The recent expansion of economic activity has been accompanied by growing global environmental and social concerns (Organisation for Economic Co-operation and Development (OECD) 2009). While posing many challenges, they also provide opportunities for businesses to engage in sustainability practices and transform their businesses so as to contribute to sustainable development (Schaltegger et al. 2017). In this context, innovation is increasingly becoming an important supportive vehicle for developing corporate sustainability management as a means both of survival and growth (Han et al. 1998; Schaltegger et al. 2017). Hence, innovation processes aimed at sustainable development (eco-innovations) have received increasing attention in recent years (Bossle et al. 2016; Marin and Lotti 2017; Provasnek et al. 2017). When pursuing sustainability initiatives including eco-innovations, the first issue to address is its assessment (Keeble et al. 2003). Since sustainability is a multidimensional concept, its measurement should consider and integrate economic, social and environmental aspects (Pope et al. 2004). Sustainability performance is a construct, and hence cannot be observed; it should therefore be anchored in observable reality by means of indicators (Escrig-Olmedo et al. 2017). Further, the measure of sustainability depends to a great extent on the indicators used (Boggia and Cortina 2010). Similarly, information plays a key role in the process of creating and diffusing sustainability innovations (Schaltegger et al. 2017). There should be mechanisms to assess the effectiveness of eco-innovations from economic, social and environmental perspectives. That is, there should be proper monitoring, measurement and evaluations regarding the progress towards the sustainability goals (Sroufe et al. 2002). However, the assessment of the impact of eco-innovations is still not adequately developed in industries such as plantation agricultureFootnote 1 unlike in the manufacturing sector (Ariza et al. 2013). Innovations in the agriculture sector are of importance because the shrinking availability and the rising cost of land, labour, water and energy pose many challenges for the industry (UN Environment Programme (UNEP) 2008). With the constant growth of population there is pressure to increase agricultural yields, which often means the use of synthetic inputs that are not environmentally friendly such as pesticides or questionable such as genetically modified crops. In order to meet these rising environmental and sustainability challenges, the agriculture industry has yet to use innovation as a tool (Negny et al. 2012; Berdegue and Escobar 2002; Diederen et al. 2003). This case study presents an approach to improving the yield while being green and how to measure those improvements in the agriculture industry. As such, the paper presents how sustainability indicators can be used to measure the effects of eco-innovations from economic, environmental and social perspectives in the Sri Lankan tea plantation sector. The literature usually recommends that a company first begins with simple, easy-to-implement measures of resource efficiency before moving into more complex indicators (Krajnc and Glavi 2003). We therefore base this paper on the initial outcomes of an experimental case study conducted on a commercial tea garden using some selected sustainability measures.
The contributions of the paper are as follows: First, the paper adds to the growing body of sustainability assessment literature (see Hamilton and Atkinson 2006; Boggia and Cortina 2010; Escrig-Olmedo et al. 2017; Krajnc and Glavi 2003) by specifically focusing on eco-innovations. In doing so, this paper develops economic and environmental indicators and to a certain extent some social indicators to assess the impact of eco-innovations. The integration of ecological, social and economic aspects is very useful for extending innovation research to sustainable development (Rennings 2000). Second, the inter-disciplinary nature of this study highlights the benefits for the plantation agriculture industry and for accounting (more broadly, business management) disciplines. This eco-innovation is based on the principles and behaviour of plant physiology and was primarily aimed at productivity improvements to derive economic gains, but eventually resulted in environmental benefits as a byproduct (Horbach et al. 2012; Organisation for Economic Co-operation and Development (OECD) 2009; Carrillo-Hermosilla et al. 2010). Hence, this study provides evidence on the lean-green relationship from the agriculture industry. From the perspective of the plantation agriculture industry, this study shows how non-technicalFootnote 2eco-innovations can be used to reduce their environmental impact while achieving economic benefits. This is particularly important since innovation is lacking in this industry (Ariza et al. 2013; Berdegue and Escobar 2002; Diederen et al. 2003). These types of innovations do not require advanced technology or large amounts of capital investment. Hence it has the potential to foster productivity levels on the agricultural plantations sector irrespective of the degree of development and growing conditions. However, the magnitude of benefits will vary with local environmental conditions. Since most of the tea producing countries are developing countries with low levels of technological development and capital investment constraints, these types of eco-innovations have the potential to improve productivity easily (Feder et al. 1985; Ongong and Ochieng 2013; Pretty et al. 2003). Since the plantation industry plays a significant economic role in these economies in terms of foreign exchange earnings and employment generation, the application and subsequent assessment of eco-innovation is of paramount importance in the face of intense pressure for better productivity and efficient resource utilization in achieving sustainable development. For the accounting discipline, this study expands the application of environmental and sustainability management accounting (EMA)Footnote 3 beyond industries such as manufacturing or service where it is commonly used. Hence it shows the usability of EMA across a wide spectrum of industries provided the appropriate indicators and mechanism are used to provide information for stakeholders.
The rest of the paper is organized as follows: The next section presents the concept of eco-innovation and its assessment through sustainability indicators. Section three provides an overview of the tea industry followed by section four on the method adopted in the case study. Sections five and six present the analysis and discussion of the study respectively. The last section provides the conclusions and directions for further research.
Innovations play a major role not only in formulating national and international economic policies but also in devising strategies for achieving sustainable development (Rennings 2000). While the concept of invention refers to a discovery, the majority of innovations are not based on discovery but are the outcome of applied research and development (Kemp and Pearson 2008). Organisation for Economic Co-operation and Development (OECD) (2005) suggests four types of innovations: product innovations, process innovations, organisational innovations and marketing innovations. This paper focuses on process innovation within the broad definition of innovation. According to Organisation for Economic Co-operation and Development (OECD) (2005), process innovation is the implementation of a new or significantly improved production or delivery method (Organisation for Economic Co-operation and Development (OECD) 2005, p. 49). Process innovations include significant changes in techniques, equipment and/or software by reducing unit costs (Kammerer 2009; Organisation for Economic Co-operation and Development (OECD) 2005; Rennings 2000) and/or improving quality (Organisation for Economic Co-operation and Development (OECD) 2005). Hence the focus is on improving the existing processes or adding new processes (Carrillo-Hermosilla et al. 2010). Despite the usefulness of this general categorization (Carrillo-Hermosilla et al. 2010), OECD categories are not sufficient for dealing with the issues of sustainable development since they do not distinguish between environmental and non-environmental innovations (Rennings 2000).
To be an eco-innovation, an innovation should be less environmentally harmful than the relevant alternatives (Kemp and Pearson 2008). Hence in a widely cited definition, Kemp and Pearson (2008) define eco-innovation as:
The production, assimilation or exploitation of a product, production process, service or management or business method that is novel to the organisation (developing or adopting it) and which results, throughout its life cycle, in a reduction of environmental risk, pollution and other negative impacts of resource use (including energy use) compared to relevant alternatives. (p. 7)
The focus of the above definition is on the results of innovations as opposed to motivation (Horbach et al. 2012). Hence it is not necessary for eco-innovations to be motivated primarily by environmental improvements (Carrillo-Hermosilla et al. 2010). It could also result as a by-product of an economic motivation to reduce costs or improve market share (Horbach et al. 2012; Organisation for Economic Co-operation and Development (OECD) 2009). Hence, eco-innovations can be environmentally motivated innovations or environmentally beneficial normal innovations (Carrillo-Hermosilla et al. 2010). Effective tools are needed to ensure the success of various environmental management practices (Sroufe et al. 2002) including eco-innovations. Yet, there is still a lack of theoretical and methodological approaches to analysing the impact of eco-innovation.
When measuring the impact of sustainable initiatives such as such sustainability production, it is difficult to have a standardized set of sustainability indicators. This is due to the enormous differences between production facilities (Veleva and Ellenbecker 2001; Krajnc and Glavi 2003; Arundel and Kemp 2009). As a solution, Veleva and Ellenbecker (2001) suggest using a combination of core and supplemental indicators in the economic, environmental and social spheres. Core indicators are calculated based on the available data using commonly measured aspects such as water use, energy use and employee. They represent a standard set of indicators that can be applied in any situation. On the other hand, supplemental indicators openly set and vary between companies/facilities. They are used to introduce flexibility by addressing additional, production-specific aspects (Veleva and Ellenbecker 2001). The environmental indicators can be input-related or output-related while the economic indicators can be financial or employee-related (Krajnc and Glavi 2003). The purpose of any of these indicators is to reflect the wholeness of the system while displaying the interaction among its subsystems (Krajnc and Glavi 2003).
In this case study, the tea industry was selected for several reasons. First, tea (Camellia sinensis) is the manufactured drink most consumed in the world (Chang 2015; Owuor et al. 2011). It is currently grown in more than 35 countries, providing a valuable source of employment and export earnings, particularly for developing countries (Forum for the Future 2014). China, India, Kenya and Sri Lanka are the worlds largest tea producing and exporting countries (Forum for the Future 2014). Second, the tea industry has recently faced many challenges mainly due to the accelerated escalation of the cost of production, drop in world tea prices, severe debilitation of tea bushes and lack of productivity improvements (International Tea Committee (ITC) 2015; Oxford Business Group 2016). Eco-innovation is of significant importance at a time when the tea industry considers resource constraints and competition for land and productivity as two of the ten challenges the industry is facing (Forum for the Future 2014). Third, since one of the co-authors is a tea planter by profession, the tea industry provided us the access and opportunity to carry out this experimental case study on a commercial tea garden while measuring its impact over a period of time.
Under commercial conditions, a tea plant is trained into a dwarf and dense bush of between 0.6 and 1.3m in height with spread branches purely for the convenience of harvesting the tender tea shootsFootnote 4 (Kumar et al. 2015; Selvendran 1970; Tea Research Association (TRA) 2015). With the frequent harvesting of emerging tender shoots, usually on a weekly basis, the tea bush is subjected to continuous trimming over a period (Ravichandran 2004). This results in a gradual display by the plant of the hedge-row-effectFootnote 5 whereby large numbers of tiny low quality shoots are formed (refer Fig. 1).
Therefore, the quality of the tea flush is in a state of gradual decline over time. Further, harvesting operations become difficult too as the shoot size gets smaller with the increased bush height. Thus, commercial tea bushes are subjected to periodic pruning almost every 35years in order to rejuvenate the tea bushes with a high quality succulent flush. However, this periodic pruning process creates several economic, environmental and social issues:
The conventional way of training/spreading tea bushes by conventional tippingFootnote 6 after pruning has limitations of expanding the bush frames. Thus it takes more than 3642months to fully re-develop the canopy cover.
The exposure of the soil is directly affected by several biotic and abiotic forces of nature, including sunlight, rainfall, wind and animal action with this sudden opening of the bush-canopy due to pruning. This process further results in severe soil degradation and wastage of other free natural resources such as sun light and rain water (refer Fig. 3).
High operational costs are entailed particularly because of excessive growth of weeds on exposed ground resulting in an amplified demand for frequent weed control and other agricultural inputs such as fertilizer, pest and disease control, etc. (Yamada et al. 2009).
A well spread bush frame is highly beneficial to crop species like tea since the active production area is the bush-canopy of the tea plant and the immature shoots (the bud and two leaves) are the commercially important part of the plant. Therefore, a quick re-establishment of the tea canopy following pruning is of utmost importance. The eco-innovation method followed is explained in the following paragraph.
Generally, pruned tea bushes are ready for the first harvest by 90days from pruning if the growing conditions are favourable. Conventionally, the tea bushes are grown to a level parallel to the ground at the first harvest itself forming a plucking table. This eco-innovative method (which we call Strip Spreading of Tea Bushes [SSTB]) allows the recovery of tea bushes from pruning to grow up to 120days without harvesting. Thereafter, the growing shoots are spread radially exposing them more to sunlight. This radial spreading of shoots is done using tight parallel stripes arranged along the tea rows. Here, the branches are temporarily held by the tight parallel stripes allowing them to shoot up more. Therefore, this process allows tea bushes to grow larger compared to conventional tipping (refer Figs. 4, 5 and 6). Since one of the co-authors who invented this idea is in the process of obtaining the patent for this innovation, there are certain technical matters that cant be disclosed in the paper as at now. Recently, in recognition of this innovation, a co-author of the paper was adjudged the 2016 Blue Economy Concept Sector Winner of the Dilmah Conservations 2016 Merrill J. Fernando Eco-Innovation Awards.Footnote 7
The concept of SSTB instead of Conventional Tipping of Tea Bushes (CTTB) after pruning offers the opportunity for early re-establishment of the canopy by engineering existing bush frames of tea, thus resolving many of the negative factors inherent in the present practice of periodic pruning.
In order to operationalize this eco-innovation, an experimental case study was launched in 2015 at Hapugastenne Tea Garden, (lat 6.872, lon 80.530) in Maskeliya, Sri Lanka. The purpose was to ascertain and compare the regeneration of the bush frame by the stripe-spreading method (treatment) against the current conventional post-pruning practice of tipping (control). Randomly selected five lots of 10mx20m experimental plots in clusters of four pairs of replicates were established in vegetatively propagated (VP) tea fields, aged between 25 and 54years since planting at three different elevation ranges. The experimental blocks and the plots were located on similar terrain, parallel orientations and also shade conditions too that were almost alike.
Recovering tea bushes after pruning were allowed to grow up to 120days and then, a radial spread of shoots was done using tight parallel stripes arranged along the tea rows instead of tipping in the treatment plots, while practising conventional tipping in the control plots declared adjoining them with the same cultivar of tea (refer Fig. 6). Both experimental and control plots were treated alike with all other agricultural practices. Data was collected methodically at regular intervals, but for the purpose of analysis they are presented for periods of 4, 6, 10 and 14months. The same workers were employed in both treatment and control plots. Instruments such as weighing scales and spray tanks used for foliar spraying were regularly calibrated. The measurements and records maintained by the plantation company were regularly audited by internal, external and statutory audit teams independently after verifying and confirming all estate records.
Since the bush canopy area coverage was the main aspect of the study, plot area was taken as a parameter. Comparatively much larger trial plots were selected in order to minimize noise and improve the precision of results and thus the credibility of the study. Measurements were taken plot-wise. This experiment was done in a VP tea where all tea bushes in a plot are descendants of a single mother plant and hence genetically alike. Any variations observed would have been due to varying environmental conditions.
In analyzing the results, some of the indicators such as weeding cost and tea output were extracted from the records maintained by the plantation company while other measures such as foliar spray waste and canopy area were measured specifically for the study by independent third party personnel under the supervision of the researchers. As mentioned at the outset, this paper presents some of the initial outcomes of this experimental study. Hence, there are aspects which have not been covered in this paper owing to practical limitations. Even though it is too early to identify the long-term outcomes of this experiment, yet the authors are of the view that the trend highlighted in this results would continue and provide useful insights for measuring the impact of eco-innovations.
The viability of the eco-innovation (i.e., SSTB approach) is assessed mainly from economic and environmental perspectives with a variety of monetary and physical EMA measures as suggested by Burritt et al. (2002). However, the study also captures some social measures as well. All these measures were based on industry norms. Hence the following section is arranged under three sections: a) economic perspective, b) environmental perspective, and c) social perspective.
The economic perspective was measured mainly through a combination of monetary and physical sustainability information by focusing on productivity (measured in terms of crop yield); foliar spray wastage and weeding cost (refer Table 1). The tea yield is an output as well as a core measure while the foliar spray wastage and weeding cost are supplemental and input indicators.
There was an initial expenditure of labour (Rs.688) and material cost (Rs. 1288) per plot in SSTB when training the tea bushes by spreading branches. Initially, after around 4 months from pruning, there was a setback seen in the crop harvested from treatment plots since they were rested without plucking. Therefore, control plots showed a comparatively higher crop up to that time. However, this situation started to change as spread branches started sprouting and yielding crop at an increasing rate of around 160days onwards (i.e. after 5 months). Early costs incurred on training of tea bushes was paid back in the next few months in the form of savings made on other inputs such as weed control, fertilizer minimizing wastage and also by the crop increment shown in treatment plots. However, the authors of this study are of the view that it is too early to go ahead with a cost benefit analysis at this point, since many more persistent benefits are yet to come and need to be evaluated over the next few years to complete one full pruning cycle. The treated area reached a 34% higher yield level compared to the control area by 6 months from pruning and continued the performance by passing 38 and 42% higher levels as against the control area (refer Table 1). Hence the treatment plots quickly overcame the problem of low crop production due to the loss of bush-canopy, which is a problem of pruning as highlighted by Selvendran (1970) and Ravichandran and Parthiban (1998a).
The next physical EMA measure observed in the study, i.e., the wastage of foliar spray inputs, was minimal in the treated plots due to a larger and thicker bush-canopy area (refer Figs. 7 and 8). However, a large amount of foliar spray was wasted and reached ground level promoting weed growth in the control plots due to exposed ground resulting from smaller bush-canopy. As shown in Table 1, the foliar spray wastage was reduced to around a 2% level from the original 60% over the period in treatment plots whereas the same in the control plots was reduced only to 25%.
Ground beneath at 08months from pruning under control plots. The weed growth on exposed ground on tea inter-rows is in the range of 10001450 weed plants per m2. This, in turn, propagates chemical tolerant harmful weeds for tea
The third EMA measure, the cost of weeding, showed a reduction in the treatment plots due to the establishment of the bush-canopy covering the ground. A growth of herbicide-tolerant creeper weeds was observed in these plots; they needed to be removed manually from the field. However, overall weeding cost was on a downward trend in the treatment plots when compared to the control plots (refer Table 1). The weeding cost gradually dropped by 32 to 35% in the treatment area as against the control area, from the 6th month to the 14th month respectively from pruning. As Channaveera et al. (2011) note, in the control plots the use of weedicide is not only ecologically undesirable but has also driven up the input costs of tea production. Moreover, this weedicide does not ideally fall on the target and becomes degraded completely to harmless compounds. They drift into the environment affecting the eco system (Chauhan and Singhal 2006). Hence, the treatment plots clearly demonstrate a notable improvement not only from an economic perspective but also from an ecological perspective. Although not quantified in this study, the use of weedicides to control undergrowth in tea estates can negatively affect local plant and animal biodiversity (Sudhi 2013).
The use of core environmental measures such as energy, water or waste is not relevant to this study. Hence, the authors had to search for supplemental measures. The environmental perspective of the eco-innovation was therefore assessed through physical EMA information by using the canopy area and ground cover (refer Table 2). Instead of quantifying carbon storage parameters the canopy area of a bush and ground cover were taken here since they are directly and broadly linked with resource use efficiency and productivity in real terms in applied agriculture. It also offers a more manageable measure to start with when compared with complex carbon storage indicators. These selected measures provide additional plant biomass while absorbing the atmospheric CO2 emissions, representing a reduction in a factor contributing to climate change (Harris 1992).
It was observed that in the treatment area, bush canopies were developed to 0.5m2 by 04months from pruning, forming 40 to 50% (average 45%) ground cover overlapping branches with neighbouring tea bushes. This was further developed into an overall 98% ground cover in the treatment plots 14months after pruning. In contrast, the bushes in the control plots were developed only to 0.450.77m2 canopy area whilst achieving 3970% ground cover within the same period.
As Table 2 shows, the tea bushes in the treatment plots has the ability to develop a 245% larger canopy area on average when compared to control plots. Undoubtedly, this increases the natural resource use efficiency of tea bushes such as sunlight, moisture and reduced foliar spray wastage. It also prevents erosion and degradation of soil, enabling the healthy growth of the tea bush. As highlighted by Owuor et al. (2011), soil is an essential environmental factor that affects the growth of tea plants and the SSTB method improves the soil of the tea plantations. Further, this concept largely contributes to minimizing environment pollution in general and improving the quality and quantity of drinking water supplied to the country for drinking, domestic and irrigation purposes.
As discussed in the extant literature, selection of suitable social measures was difficult. The social perspective of the eco-innovation was measured by using the income generated for the workers from improved land productivity. As shown in Table 1, the increased productivity of 34% (from 6months onwards) resulted in an equivalent amount of additional income for the workers. Also, there were many benefits that are difficult to quantify such as soil conservation, improved the water sources and the quality of water for the workers and community, in general. As elaborated above, SSTB method suppresses the weed growth (as given in Figs. 7 and 8) by efficient trapping of both sunlight and foliar sprays while minimizing the chance of reaching such resources down to the emerging weeds on the ground. Thus, chemical weeding is not required in SSTB after 06months from pruning and any emerging odd weeds could be managed by periodic spot weeding. Therefore, detrimental impacts of weedicide chemicals on the sprayers, workers and community could be eliminated by SSTB. Some of these positive impacts are presented in Table 3.
Nowadays there is increased concern about the use of weedicides that may lead to their residues affecting the food chain causing harm to human beings and animals (Chauhan and Singhal 2006). Hence under the SSTB method, due to the low use and escape of agricultural inputs (especially weedicides) from the farming system, the environment would become less hazardous to humans and animals.
The above analysis presents some interesting points for discussion. The results show that this process of eco-innovation improves the existing tea pruning process by reducing the environmental impact while improving societal and economic benefits. Further, this innovative method (i.e. SSTB over CCTB) improves land productivity and agricultural resource utilization, two major problems envisaged by Forum for the Future (2014) in its tea 2030 vision. SSTB actually lowers the frequency of pruning and improves the land productivity and resource use efficiency of tea plantations, thus lowering the operational cost and unit cost of production. Hence this method leads to sustainable agricultural practices by improving the ability of the agricultural systems to maintain crop productivity in the long run while at the same time producing environmental and social benefits (Francis et al. 1987; Gafsi et al. 2006; Lichtfouse et al. 2009; Peiris and Gunarathne, 2015). These types of investments do not require substantial capital investment or deployment of advanced technology or skilled labour. Hence, these non-technological innovations (Organisation for Economic Co-operation and Development (OECD) 2009) with minimum capital, technological or labour investments can be used to reduce the environmental and social impact while achieving economic benefits. Since most of the top tea producing countries are developing countries with limited access to advanced technology and major constraints on large capital investments, these types of innovations have the potential to improve productivity with minimum investments. From another dimension, this study supports the lean-green concept in the agricultural industry since it uses less agricultural inputs to improve financial performance while preventing environmental burdens and contributing to social equity (Abreu et al. 2017; Des et al. 2013; Rothenberg et al. 2001). This eco-innovation was not initially intended (Carrillo-Hermosilla et al. 2010; Horbach et al. 2012) to bring about environmental or social improvements but to reduce crop loss in the pruning cycle. However, the synergistic benefits of lean by way of using less waste of inputs and better use of land has derived positive results in the economic, environmental and social spheres. This suggests that managers broaden their scope of analysis beyond the economic dimensions to incorporate the wider environmental and social benefits when assessing eco-innovations. It will also make environmentally friendly investments more acceptable (Environmental Protection Agency (EPA) 1995).
In this case study several indicators were used to assess the impact of eco-innovation. In order to capture the multidimensionality of sustainability these measurements should consider the economic, social and environmental aspects (Pope et al. 2004). Due to the diverse nature of operations in different industries, it is difficult to have a standardized set of indicators to measure the impact of sustainability initiatives (Krajnc and Glavi 2003; Veleva and Ellenbecker 2001). Although the extant literature states that the core indicators are common for any industry (Veleva and Ellenbecker 2001), the use of these indicators is even difficult in the plantation agriculture industry which covers a wide range of crops such as tea, palm oil, cocoa, rubber and coffee. This makes the use of supplemental indicators essential (Veleva and Ellenbecker 2001). However, the use of supplemental indicators makes the inter-industry comparison of eco-innovations difficult as there are few common indicators. Further, we do not suggest that the intra-industry comparison is somewhat easier. Owing to the differences in many factors such as soil condition, weather patterns and labour practices, there will be difficulties in making intra-industry comparisons also. These differences call for the application of additional indicators. However, given the need for a manageable number of indicators that are simple and easy to apply (Krajnc and Glavi 2003), the use of multiple indicators could render the measurement process of eco-innovations complex and unmanageable. Hence, the selection of sustainability indicators to assess the impact of eco-innovations necessitates a trade-off between accuracy and manageability. On the other hand, the use of generic measures such as carbon storage can be too complex. This can be an important constraint for many small and medium sector enterprises in developing countries where the plantation agriculture industry plays a key role.
Echoing a similar challenge that prior researchers have encountered, the present researchers too had a problem in selecting the appropriate sustainability indicators for the assessment of social dimension in eco-innovations. This is mainly because, so far, the social side of sustainability and hence the social sustainability indicators have received little attention (Dillard et al. 2009; Gunarathne et al. 2016; Krajnc and Glavi 2003; Von Geibler et al. 2006). The social perspective of sustainability is intangible and qualitative in nature and lacks consensus on relevant criteria (Von Geibler et al. 2006). This calls for innovation in accounting (Schaltegger et al. 2017) to develop indicators and mechanisms to assess the various facets of sustainable development.
Problems associated with measuring sustainable development (Hamilton and Atkinson 2006; Boggia and Cortina 2010), corporate sustainability performance (Escrig-Olmedo et al. 2017), and developing suitable indicators (Krajnc and Glavi 2003) are common to the assessment of eco-innovations. Hence this case study, while highlighting the difficulties in measuring impact of eco-innovations, emphasizes the need for the further development of sustainability indicators. Without proper assessment it is difficult to gauge how far the intended outcomes have been reached. As Krajnc and Glavi (2003) suggest to cope with the complexity of sustainability-related issues for different systems, the indicators have to reflect the wholeness of the system as well as the interaction of its subsystems (p. 281). We used only simple and easyto-implement indicators, but when a company advances it is necessary to move towards more complex indicators (Escrig-Olmedo et al. 2017; Krajnc and Glavi 2003). Perhaps, the way forward can be the development of fuzzy multi-criterion decision-making (MCDM) methods (Escrig-Olmedo et al. 2017; Boggia and Cortina 2010; Krajnc and Glavi 2003) to assess the impact of eco-innovations. On the other hand, most of the impact of eco-innovations are long term, particularly in the plantation agriculture industry. Therefore, in addition to the selection of a set of indicators there is the challenge to determine the suitable time frame for the assessment. This highlights the challenges faced in the development of indicators considering the main dimensions of sustainability indicators, i.e. unit of measurement, type of measurement, tracking period and measurement boundary (Krajnc and Glavi 2003).
Our case study further highlights the difficulties in carrying out a priori cost-benefit analysis in terms of an investment appraisal (Drury 2009; Environmental Protection Agency (EPA) 1995) since eco-innovations would involve capital expenditure. This difficulty could arise owing to several reasons. One reason is the difficulty in monetizing some of the environmental and social impact. As explained in the previous paragraph, another issue lies with the selection of the suitable indicators and the time period. These issues converge to highlight the typical problems associated with capital budgeting (refer Rossi 2014; Drury 2009; Brounen et al. 2004). Another interesting issue that makes a priori cost benefit analysis difficult is the nature of eco-innovations. As most eco-innovations are unintentional (Carrillo-Hermosilla et al. 2010; Horbach et al. 2012; Organisation for Economic Co-operation and Development (OECD) 2009) an entity would only realize its potential once the innovation is carried out. Hence what is possible is post-completion sustainability investment appraisal only. According to Burritt et al.s (2002) comprehensive framework, this leads a company to apply ex-post investment assessments which should be done both in physical and monetary terms.
The purpose of this case study was to contribute to the body of knowledge on the assessment of eco-innovations by carrying out an experimental case study in the agricultural plantations industry. Innovations mainly aimed at enhancing economic gains can have accidental impact on the environment. However the assessment of the impact of these eco-innovations is the challenge. Since due to the underdeveloped theoretical and methodological approaches to analyze these benefits (Rennings 2000; Peiris and Gunarathne, 2015), the study used the triple bottom line approach. In doing so physical and monetary sustainability information was used (Burritt et al. 2002, International Federation of Accountants (IFAC) 2005) to quantify these impacts. Yet there are many potential impacts that were not captured in the present paper. It is only when these impacts are considered that the full benefit of eco-innovations can be evaluated. This case study reveals the difficulty in having a standardized set of indicators to measure the impact of eco-innovations owing to the multidimensionality of sustainability. Further, this case study emphasizes that the problems associated with measuring sustainability are common to the assessment of eco-innovations as well. Hence there is a need for further development of sustainability indicators to make inter and intra industry comparisons of the eco-innovations meaningful. The way forward would be to adopt broad sustainability indicators that represent the wholeness of the system while capturing the long term impacts.
The findings of this case study can have several limitations. Since the study was carried out in a particular tea field with specific characteristics there is a need to replicate the study under different conditions and for different types of perennial crops. This study only presents the outcomes of this study covering 14 months. However, in the agricultural plantation sector there are long-term impacts across a variety of aspects. This creates a need to identify the benefits or impacts over longer time periods. In this study some of the broader benefits and/or different aspects were not measured due to various practical difficulties. For instance, many scholars have drawn attention to the quality of tea after pruning (see Grice 1985; Owuor et al. 1990; Ravichandran 2004; Ravichandran and Parthiban 1998b). However, the study did not observe some of the parameters as the purpose of this paper was to present the early results of the experiment. Hence it would be necessary to investigate these aspects in future studies.
Plantation agriculture is a form of commercial farming where crops are grown for profit (Geography 2012). Some of the main plantation crops include beverages (such as tea, coffee and cocoa), rubber, oil palm, cotton, beverages (such as coffee, tea and cocoa), fruits (such as pineapples and bananas), rubber, oil palm, cotton, and sugarcane.
EMA is a decision support tool when organizations follow various environmental management strategies/practices (Bennett et al. 2002). It uses a wide array of accounting tools and techniques that provide physical and monetary information for decision makers.
Burritt R, Hahn T, Schaltegger S (2002) Towards a comprehensive framework for environmental management accounting: links between business actors and environmental management accounting tools. Aust Account Rev 12(2):3950
Channaveera H, Lokeshaa LB, Hugara JB, Deshmanyab GSB (2011) Impact of MGNREGA on Input-use Pattern, Labour Productivity and Returns of Selected Crops in Gulbarga District, Karnataka. Agric Econ Res Rev 24:517523
Escrig-Olmedo E, Muoz-Torres MJ, Fernndez-Izquierdo M, Rivera-Lirio JM (2017) Measuring Corporate Environmental Performance: A Methodology for Sustainable Development: Measuring Corporate Environmental Performance. Bus Strateg Environ 26(2):142162
Gunarathne N, Samudrage D, Wijesinghe DN, Lee KH (2016) Fostering social sustainability management through safety controls and accounting: A stakeholder approach in the mining sector. Account Res J 29(2):179197
Owuor PO, Kamau DM, Kamunya SM, Msomba SW, Uwimana MA, Okal AW, Kwach BO (2011) Effects of genotype, environment and management on yields and quality of black tea. Genet. Biofuels Local Farm. Systems. Sustain Agric Rev 7:277307
Peiris, HMP Gunarathne, AD Nuwan (2015) Sustainable Weed Management in the Commercial Tea Industry: The Case of Hapugastenne Estate, Maskeliya. Available at https://ssrn.com/abstract=2706978. Accessed 08 Apr 2017
Provasnek AK, Sentic A, Schmid E (2017) Integrating Eco-Innovations and Stakeholder Engagement for Sustainable Development and a Social License to Operate. Corp Soc Responsib Environ Manag 24(3):173185
Ravichandran R, Parthiban R (1998b) Changes in enzyme activities (polyphenol oxidase and phenylalanine ammonia lyase) with type of tea leaf and during black tea manufacture and the effect of enzymi supplementation of dhool on black tea quality. Food Chem 62(3):277281
Sudhi KS (2013) Weedicides will affect local biodiversity: greens, The Hindu. Available at http://www.thehindu.com/news/cities/Kochi/weedicides-will-affect-local-biodiversity-greens/article5282557.ece. Accessed 12 Dec 2016
Tea Research Association (TRA) (2015) Young Tea Management, Tocklai Tea Research Association of India. Available at http://www.tocklai.net/activities/tea-cultivation/young-tea-management/. Accessed 01 Mar 2016
Yamada A, Yamamoto T, Yoshimura Y, Gouda S, Kawashima S, Yamazaki N, Yamashita K, Kataoka M, Nagata T, Terada H, Pfeifferf DR, Shinohara Y (2009) Ca2+induced permeability transition can be observed even in yeast mitochondria under optimized experimental conditions. Biochim Biophys Acta 1787(12):14861491
The authors are grateful for helpful comments and suggestions from the anonymous reviewers as well as conference participants at the 2016 Environmental and Sustainability Management Accounting Network Conference in Asia Pacific (EMAN-AP), Korea.
Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.
Gunarathne, A.D.N., Peiris, H.M.P. Assessing the impact of eco-innovations through sustainability indicators: the case of the commercial tea plantation industry in Sri Lanka. AJSSR 2, 4158 (2017). https://doi.org/10.1186/s41180-017-0015-6
By using this website, you agree to our Terms and Conditions, California Privacy Statement, Privacy statement and Cookies policy. Manage cookies/Do not sell my data we use in the preference centre.
Southeast Asia Low Price Small Soft Rock Briquetting Plant Sell At A Loss Largecalcitedisk Granulatorin Vientiane Laos Southeastasia Iron Ore Mining Equipment Products Are Most Popular In Africa Domestic Market And Southeastasiayou Can Ensure Product Safety By Selecting From Certified Suppliers Including 3826 With Iso9001 1173 With Other.
If you have any problems or questions about our products or need our support and assistance, please contact us and you will be replied within 24 hours. We promise we will never reveal your information to the third party. Thank you!
We Have Large Carbon Blackdryermachine In Katsina Nigeriaafrica,Large Carbon Black Ball Mill In Kano Nigeriaafrica.Carbon Black Briquette Machinefor Our Malaysia Clientcoal Jun 26 2014Carbon Black Briquette Machinefor Our Malaysia Client Are The EP Of Briquetting Machine Pellet Mill. Details
Otsuka Cone Crushers Parts In Liberia. Stone Crusher Cone Jaw Crushers Machine. Stone Crusher JXSC Company Stone Rock Crushers Include Cone Crusher Jaw Crusher Impact Crusher Mobile Crusher Sand Making Machine Mobile Crushing Plant Hammer Crushing Which Can Crush With More Than 200 Kinds Of Industrial As Pebble Granite Basalt Iron Ore Limestone Quartz Diabase Iron Ore
Dry Mixed Mortar Plant. Production Capacity 200,000-500,000 Tons Per Year Component Parts Material Storage Tank, Sand Dryer, Batching Apparatus, Mixer, Dry Powder Packing Machine, Dust Collector And Conveyor. Application Fields To Produce Single Component And Multiple Component Mortar Products Such As Dry-Mixed Mortar, Water Proof Mortar, Adhesive Mortar, Plaster Anti-Crack Mortar And ...
New River Sand Bucket Conveyer In Harper Liberia Africa ... Aba Nigeria Africa Medium Salt Bucket Conveyer Sell At A ... Large Basalt Sand Makersellinguinea Low Price Medium Basalt Beltconveyor Sellat A ... Conveyer Sell At A Loss New Ceramsite Ball Mill In Nuwara Eliya Sri Lanka South Asiadec 10 ... Is A Highlyvalued Skill In Both Sri Lanka And South Asia For Locals It Opens Up Whole New.
Efficient New Diabase Spiral Chute Separator Sell At A Loss In ... Spiral Chute Separator Is The Best Equipment For Mining And Ore Beneficiation. ... Efficient Environmental Diabase Bucket Elevator Sell At A ... Economic Small Quartz Spiral Chute Separator Sell It At A Bargain Price In North America The ... The Ore Concentration And Tailings Calgary Low Price New Diabase Spiral Chute Separator ...
Medium Diabasewood Chip Dryerin Liberia Africa. High Endmedium Diabase Dryermachine For Sale In Monrovialiberia Africa. Small Stone Sawdustdryerin Monrovialiberia Africasmalllimestone Ball Millin Monrovialiberia Africaball Mill Ball Mill Is The Key Equipment For Grinding After The Crushing Process Which Is Widely Used In The Manufacture ...
Irbid Low Price Environmental Coal Face Briquetting Machine. New Silicate Chute Feeder In Livingstone Zambia Africanew Silicate Chute Feeder In Livingstone Zambia Africalivingstone Zambia Africa Medium Granite Chute Feedersellat A Loss Zambia Natural Stone Mining 7 Results We Have Forsellcitrine Stones For Sale From Our Mines,Irbid Low Priceenvironmental Coal Face Briquettingmachine
Tangible Benefitsnew River Sand Ore Concentratein. Tangible Benefitssmall Soft Rock Aggregate Mobile Jaw Crusher Sellinhobart Australia Oceania,Recifetangible Benefitsrock Briquetting Machine For Sale Gweru Small Kaolin Briquetting Machine Sellit At A Bargainpricesmall Soft Rock Briquetting Machine In Liberia Harare High End Large ...
Dolerite And Diabase Rocks Are Used As Crushed Stone In Road Making, Concrete Mixture In Rough Masonry, And Block Paving And Ornamental Stone In Monumental Purposes. FIGURE 4.19 . Dolerite Is A Medium-Grained Mafic Intrusive Igneous Rock Composed Primarily Of Plagioclase Set In A Finer Matrix Of Clinopyroxene Olivine, Magnetite And Ilmenite.
New River Pebble Rod Mill In Zaria Nigeria Africa. Zaria Nigeria Africa Newbrick And Tilerod Millwe Have Largebrick And Tilerodmillinzarianigeria Africa,Bricks Innigeriatypes Bricks 336Tiles127 Granite 27 Slabs 17 Staircase 10 Blocks 3 Roofing Materials 3 Rooftiles3 Wall 104 African 61
High End Environmental Chrome Ore Jaw Crusher Manufacturer ... Low Price New Chrome Ore Chute Feeder Sell In Liberia Africa ... Parishigh End Environmentalpottery Feldspar Mining Equipment Sell. Tangible Benefits Medium ... Crushing Equipment, Milling Equipment,Dressing Equipment,Drying Equipment And ... A World With No Shortage Of Tile Companies Somemanufacturersand Retailers Are...
Furthermore Other Vernacular Names Of Briquette Plant Are Screw Briquetting Machine Briquette Press Screw Briquetting Mud Press Tuda Machine Getting The Machine Saw Dust Machine Jumbo Machine Rice Husk Briquette Machine And More We Prefer To Call Them Prime 40 Classic 60 Standard 70 Bull 80 Supreme 90 And Everest 100 Get Price. Get Price
Sodium Cyanide Briquetting Machine In South Africa. Briquette Machine Price In South Africa Henan Mining.Briquette Machine Brick Making Machine Block South Africa Enca It Has Not Been A Good Year For The Wallets Of South African Consumers With The Latest Blow Being The Fuel Price Spike That Came Into Effect At Midnight Petrol Went Up By 49 Cents A Litre While Diesel Prices Rose By 59 Cents Live.
Liberia Tangible Benefits Small Iron Ore Disk Granulator. Monrovia Liberia Africa Tangible Benefits Large Iron Ore. Monrovia Liberia Africa Tangible Benefits Large Iron Ore Disk Granulator Sell Ball Mill For Iron Ore 280 Ball Mill Is The Key Equipment For Recrushing The Materials After They Are Ball Mill Is Widely Used For The Dry Type Or Wet Type Grinding Of All Kinds Of Ores And Production ...
Dental Stone Jaw Crusher Stone Crusher JXSC Company Stone Rock Crushers Include Cone Crusher Jaw Crusher Impact Crusher Mobile Crusher Sand Making Machine Mobile Crushing Plant Hammer Crushing Which Can Crush With More Than 200 Kinds Of Industrial As Pebble Granite Basalt Iron Ore Limestone Quartz Diabase Iron Ore Gold Copper Etc Primary And Fine Crushers Are The Type Of ...
High Quality Talc Ceramic Sand Kiln In Jakarta Rotary Kiln. Medium Diabase Ceramic Sand Kiln In Harper Liberia Africa. High End Medium Concrete Agitation Tank In Harper Liberia High End Medium Concrete Agitation Tank In Harper Liberia Africa Monrovialiberiaafricahigh Endlarge Talc Magnetic Separator Price Largecoal Ball Mill Inmonrovialiberiaafricaball Mill Ball Mill Is The Key Equipment For ...
Brisbane High Quality Small Salt Mobile Crusher Sell It At A Bargain Price. High Quality Small Salt Mobile Crusher Sell It At A Bargain Price In New York City We Are Here For Your Questions Anytime 247 Welcome Your Consultation Get Price Genoa Italy Europehigh Qualitymedium Rollcrusher Sell Italy Europe Mediumsalt Combinationcrusher Sellat A Loss High End Salt Dryer Machine Sell It At A ...
Olbia Stone Is Located In Antalya, Turkey, And Has Worked In The Mining Sector For A Period Exceeding 14 Years With Its Experienced And Qualified Staff. As Stone Specialists, We Are Very Experienced At Helping Architects, Designers, Developers, And Their Clients Create The Desired Look And Feel For Any Residential Or Commercial Project.
Briquetting Plant For Sale Book Now. Briquettes One Stop Solution For All Your Briquette Buysale Needs. ... A Briquette Or Briquet Is A Compressed Block Of Combustible Biomass Material Such As Saw Dust ,Bagasse, Wood Chips Etc. Used For Fuel In Boilers And Other Heating Applications. The Term Comes From French Language And Is Related To Bricks.
Cement Grinding Plant. Feeding Size 25Mm Production Capacity 200Td-8,000Td Technological Features Crushing Raw Materials, Pre-Homogenizing Materials, Arranging Ingredients, Efficient Grinding, Homogenizing Materials, Suspending Pre-Heater And Decomposing Furnace, New Type Cooler, Cement Dosing And Grinding.
Efficient Diabase Hammer Crusher Sell At A Loss In Darkhan . Indonesialarge Diabasebriquetting Machinesell At A Losscarbon Briquetting Machine Ball Press Machinethe Carbon Black Briquetting Machine Designed...
Briquetting Burnt Dolomite Powder For Recycling In Steel Plants. Waste In The Steel Industry Case By Its Small Particle Size. ... Utilizing Burnt Dolomite Powder By Briquetting With Different Binders Include Syrup Lime ... An Excellent Chemical Composition Of High Content Of Active Mgo And Low Free Water Content. ... Ate The Burnt Dolomite Lump Quality In This Experiment. ... Quette Press Is ...
Kaoline Briquetting Machine In South Africa Production Capacity 065615Th Feeding Size 25Mm Discharging Size 0075089Mm Airswept Coal Mill Is The Most Commonly Used Coal Mill And It Is Professional Coal Powder Making Machine Mainly Used In Cement Plants Thermal Power Plant And Other Industrial Production More. Get Price.
Foid Gabbro Briquetting Machine In Cambodia. Azoppo Laos Southeast Asia Low Price Medium Diabase Sand Washer Selltangible Benefits Small Silicate Jaw Crusher Sell In Azoppo Laos Southeast Asia Gwangju Tangible Benefits River Pebble Briquetting Machine Sellsep 12 2019 River Pebble Is A Kind Of Pure Natural Stone Naturally Formed After A Long Period Of River Water Impact Extrusion Friction ...
Jul 02 2019 This Underground Mine Project With A Targeted Production Of 33 Mt Of Ore Per Year Is Using Multiple Mining Methods Including Room And Pillar And Long Hole Stopping An Aerial Ropeway System Will Be Used To Convey The Ore From The Mine Site To The Process Plant Site Across An 800 M
Crusher And A Screening Plant In Kazakhstan,Crusher And A Screening Plant In Kazakhstan Aggregate Crusher Plant Videos Page You Can See All Videos In This Page Mobile Crushing Screening Plant Kazakhstan Aktao Mobile Crusher Facilities Mobile Crusher DM Crushers 90 0232 864 14 16 Stone Crushing Screening Plant DM Machine...As A Leading Global Manufacturer Of Crushing Equipment,
Liberia, Africas Largest Iron Ore Exporter The Liberia Mining Company Was The First Of Four Iron Ore Companies Which Produced And Shipped Such Large Quantities Of Iron Ore That In The 1960S And 1970S Liberia Became Africas Largest Iron Ore Exporter And Even The Third On The World List Of Iron Ore Exporters. In 1958 Followed A Concession
Stones1.Comampnbspis The International Portal For Worldwide Stone Industry. This Portal Is An Active Business-To-Business Website For All Stone Suppliers And Their Products Like Stones. We Bring Companies Worldwide Together And Give Them Opportunities To Increase Their International Business.Ampnbspat The Moment We Have 1760 Suppliers From More The 100 Countries Worldwide Registered At Stones1 ...
Stones1.Com Is The International Website For The Worldwide Stone Industry. This Portal Is An Active B2B Website For All Stone Suppliers And Their Products Like Stones. In This Section You Can Find 1760 Stone Suppliers Registered On Our Portal. The Companies Are Divided Into Suppliers For Granite, Limestone, Marble, Sandstone, Slate And More. We Have Stone Suppliers In Africa, Asia, Europe And ...
Mineral Powder Briquetting Machine Can Press Mineral Powder Into Ball At One Time With The Features Of High Productivity And Large Strength. And Finished Product Can Be Directly Smelted In Blast Furnace. In The Transportation And Handling Process The Finished Product Is Not Easily Broken. Mineral Powder Briquette Making Machine Not Only Can .
This Is The Biggest Diabase Quarry. It Has The Potential To Deliver Blocks Of Unusual Size. The Production Amounts To 2000 Cubic Meters Per Year. The Quarried Stone Is Sold As Blocks But Also To Be Reshaped For Different Construction Purposes Such As, For Instance, Kitchen Countertops. Diabase Is In Essence A Soft Dark Brown Stone.
Species domestication is generally characterized by the exploitation of high-impact mutations through processes that involve complex shifting demographics of domesticated species. These include not only inbreeding and artificial selection that may lead to the emergence of evolutionary bottlenecks, but also post-divergence gene flow and introgression. Although domestication potentially affects the occurrence of both desired and undesired mutations, the way wild relatives of domesticated species evolve and how expensive the genetic cost underlying domestication is remain poorly understood. Here, we investigated the demographic history and genetic load of chicken domestication.
We analyzed a dataset comprising over 800 whole genomes from both indigenous chickens and wild jungle fowls. We show that despite having a higher genetic diversity than their wild counterparts (average , 0.00326 vs. 0.00316), the red jungle fowls, the present-day domestic chickens experienced a dramatic population size decline during their early domestication. Our analyses suggest that the concomitant bottleneck induced 2.95% more deleterious mutations across chicken genomes compared with red jungle fowls, supporting the cost of domestication hypothesis. Particularly, we find that 62.4% of deleterious SNPs in domestic chickens are maintained in heterozygous states and masked as recessive alleles, challenging the power of modern breeding programs to effectively eliminate these genetic loads. Finally, we suggest that positive selection decreases the incidence but increases the frequency of deleterious SNPs in domestic chicken genomes.
This study reveals a new landscape of demographic history and genomic changes associated with chicken domestication and provides insight into the evolutionary genomic profiles of domesticated animals managed under modern human selection.
All organisms carry a certain level of deleterious mutations in their genomes, which can potentially affect their fitness [1, 2]. The majority of these harmful mutations are detrimental and recessiveonly a few are dominant or recessive lethal . Such mutations can best be seen as high-impact mutations (that is, affecting the functioning or expression of a gene) [4, 5]. Most of them have a negative effect; however, some may result in a desirable phenotype and are therefore maintained by natural and artificial selection. Some of these alleles that are preferred in an artificial breeding setting would nevertheless be detrimental in the wild. The evolution of domestic species is characterized by the exploitation of high-impact mutations during inbreeding, artificial selection, and post-divergence gene flow [6,7,8,9,10], which could affect the occurrence of both desired and undesired high-impact mutations . Extensive studies have reported that domestic species, such as horses , dogs , rice [14, 15], sheep , and tomatoes , are burdened by many more deleterious mutations than their wild relatives. The cost of domestication hypothesis was proposed to explain this general pattern observed in these domestic species . It suggests that bottlenecks along with domestication reduced the power of purifying selection to remove deleterious variants, therefore resulting in a dramatic accumulation of deleterious variants in domesticated species. However, this model cannot be generalized to all major domesticates because some of them lack a domestication bottleneck [18, 19]. For example, genomic assessment of pigs , bees , and some crops  exhibited no significant historical decline in their genetic diversity relative to respective wild progenitors.
Chicken is believed to have been domesticated from the red jungle fowl (RJF). Early genomic studies have identified a number of variants that differentiate chicken from RJF, facilitating our understanding of the genetic changes underlying chicken domestication [22, 23]. It was thought that chicken has been domesticated via a commensal pathway within the Holocene, in which its early domestication was assumed to be fully unintentional  and not marked by a bottleneck . However, some studies proposed a contradictory opinion based on the observations of evaluated high-impact mutations in specific chicken breeds [2, 24], although the establishment of these fancy and commercial birds has likely resulted in a more recent bottleneck. To date, whether there was a domestication bottleneck, its strength and effect, and how it potentially shaped the pattern of high-impact mutations in relation to other factors, including admixture and selection, are unresolved in domestic chicken.
Measuring the magnitude of domestication bottleneck by direct comparison of genetic diversity in current domesticates with their true wild progenitors is often impossible (e.g., extinction of the ancestors of cattle and horses) or complicated by several factors [8, 25, 26]. First, accurate identification of the sole ancestor(s) of domesticated species remains very challenging because the potential wild relatives either continue to evolve as closely related genetic entities with a large geographic range (e.g., RJFs and gray wolves) [27,28,29] or survive only in very small fragmented populations (e.g., sheep, goats, and buffaloes) [30, 31] due to overhunting among other human activities. Second, hybridization between domesticated and wild populations is common in nature and thus could mislead the estimation of their genetic differences [32, 33]. Domesticated chickens have been affected by gene flow via hybridization with other RJFs and jungle fowl species over thousands of years [34, 35]. RJFs are widely distributed and could be assigned into five subspecies (G. g. spadiceus, G. g. murghi, G. g. jabouillei, G. g. gallus, and G. g. bankiva) ranging across South and Southeast Asia where they may have been hybridizing with village hens . The third is the aforementioned issue that wild species can rarely escape from climate and anthropogenic pressures, and this creates somewhat parallel trajectories to evolution under domestication [28, 37].
In the first phase of our 1K Chicken Genomes Project (1K CGP; https://bigd.big.ac.cn/chickensd/), through sequencing and analyzing 863 genomes from both jungle fowls and indigenous chickens sampled across South, Southeast, and East Asia as well as Europe (including 149 RJFs covering all five subspecies sampled in their natural ranges), we demonstrated that all domestic chickens were monophyletic, derived from an RJF lineage of G. g. spadiceus (GGS) whose present-day range is predominantly in northern Thailand, southwestern China, and Myanmar, and then regained genetic diversity via introgression from additional RJF subspecies and jungle fowl species during their dispersals out of the domestication center . In this study, based on the new knowledge and genomes (including 696 domestic chickens spanning Eurasia and 45 GGS from Thailand and Yunnan Province, China), we examined the demographic history for chickens before and after their domestication, investigated the distribution and frequency of high-impact mutations across their genomes, and estimated the genetic cost of chicken domestication and breed formation.
To have baseline information on the genomic diversity for present-day domestic chickens and GGS, we estimated nucleotide diversity () for each population. The average for all domestic chickens was 3.26e3, slightly higher than that for GGS (mean 3.16e3; P < 2.2e16, Wilcoxon signed-rank test; Fig. 1a). We note that this result should be interpreted with caution because our sampling of GGS likely did not cover all their genetic diversity while our chicken samples were from a wide range sampling spanning Eurasia. Pooling analysis of genomes from these diverse chicken populations together possibly inflates the estimation of genetic diversity (Additional file 1: Figure S1).
Genomic diversity and demographic history for both domestic chicken and G. g. spadiceus. a Nucleotide diversity for domestic chicken and G. g. spadiceus. In this analysis, the average nucleotide diversity for domestic chicken was calculated based on 696 samples, and for G. g. spadiceus, it was calculated based on 35 samples (after removing 10 admixed samples). b MSMC analysis of the historical population size of 18 chicken populations and GGS. c SMC++ analysis of the historical population size of 17 chicken populations and GGS. A bottleneck is evident in all chicken populations and pronounced in commercial chickens. Breed information for commercial chickens was in blue. d Dadi analysis showing the divergence and splitting of domestic chickens from GGS
We used the pair-wise sequential Markovian coalescent (PSMC)  approach to estimate the historical effective population sizes (Ne) of domestic chickens and GGS. As the efficiency of this analysis relies on heterozygotes across genomes , the result from low-coverage genomes is unreliable. The number of high-coverage genomes in 1K CGP is limited , so we also included recently published chicken genomes [35, 40, 41] with a coverage of 20-folds in this analysis (Additional file 1: Table S1). Our data contain genomes from GGS and 18 chicken populations including commercial breeds (White Leghorn, White Recessive Rocks, Rhode Island Red, and Cobb chicken), Ethiopian, Sri Lankan, Laos, and Chinese local chickens. The estimations were scaled by a mutation rate of 1.91e9 substitution per site per year and a generation time of 1 year . PSMC revealed that both domestic chickens and GGS had nearly identical demographic histories before 20 thousand years ago (kya) (Additional file 1: Figure S2), which is expected as the chicken was originated from GGS . Specifically, initialed at 1 million years ago (Mya), Ne for chicken and GGS showed expansion and reached a maximum of around 100 kya, followed by continuous contraction until 20 kya. The cycles of past population expansions and contractions were similar to those observed in other wild birds, supporting the claim that climate fluctuations during the Quaternary have likely shaped the evolution and speciation of many bird species .
However, PSMC has limited power to reveal the recent Ne within 10 kya. We then used MSMC , a method similar to PSMC, which could analyze genomes from more than one individual for each population and therefore has an enhanced power to infer the demographic changes for relatively recent evolutionary events like domestication. Our estimations were based on four haplotype genomes (two individuals) for each population. Consistent with PSMC, MSMC revealed a comparable and dramatic Ne contraction for 18 chicken populations and GGS between 100 and 20 kya (Fig. 1b). Thereafter, chicken and GGS showed obvious differentiation. Specifically, Ne for GGS remained relatively constant before the rapid decline onset ~8 kya but then stabilized ~4 kya, while domestic chickens showed a continuous Ne decline until Yunnan local chicken and Yunnan game fowl recovered ~67 kya and other chicken populations recovered later ~24 kya. Commercial chicken breeds, including White Recessive Rocks, Cobb chicken, White Leghorn, and Rhode Island Red, have much smaller Ne than other chickens, and their Ne recovered much later (~2 kya), consistent with the fact that commercial chickens have been subject to intensified artificial selection and inbreeding. It should be noted that more recent Ne estimated by MSMC tends to be inflated , especially in analyzing more than two haplotypes. Here, we further inferred historical Ne for GGS and each chicken population using SMC++ , a method estimating demographic histories based on multiple genomes without phasing. For each population, we allowed five genomes with sequencing coverage over 15-folds, yielding a total of 17 chicken populations for the analysis from our current dataset (Fig. 1c). This analysis also revealed strong evidence of domestication bottleneck for chicken compared with GGS, broadly consistent with the result from MSMC. Compared with MSMC, SMC++ has a higher resolution for estimating recent population histories. For example, SMC++ analyses also revealed that commercial chickens (White Leghorn, White Recessive Rock, Rhode Island Red, and Cobb chicken) have a stronger bottleneck and much smaller recent Ne compared with other chickens. Ne for Yunnan local chicken, Liyang chicken, White Recessive Rocks, Sri Lankan local chicken, Ethiopian local chicken, and game fowls showed a recent recovery after the bottleneck during 10 kya.
Because PSMC, MSMC, and SMC++ do not take into account the possible effects of admixture [46, 47], the estimated initiation of Ne differentiation does not necessarily correlate with the splitting time. To further infer the evolutionary history of domestic chickens, we used dadi  to fit the joint site frequency spectrum (SFS) between domestic chicken and GGS populations. We tested four assumed demographic models (Additional file 1: Figure S3-S4 and Tables S2-S3) and found that model 3 had the highest likelihood (Fig. 1d), suggesting its best fit to observed SFS. Under this model, we estimated that modern domestic chickens and GGS separated from each other ~12,300 (95% confident intervals (CI)10,80015,500) years ago. After that, GGS showed a slight expansion in Ne until 10,300 years ago (95% CI 930012,700), followed by a contraction from around 257,000 down to 154,000 birds, which was likely resulted from recent habitat loss and overhunting. On the contrary, the average Ne for domestic chickens dramatically declined from around 138,000 birds on their separation from GGS down to 52,000 until ~6990 (69008900) years ago when they started to be recovered up to ~152,000 birds till today. MSMC, SMC++, and dadi analyses suggested that domestic chickens experienced a continuous Ne decline since their splitting off from GGS, indicating a bottleneck in chicken domestication. We noted that admixture with local jungle fowl or other domestic chicken populations is pervasive , which likely affects the inference of demographic history , so the bottleneck time we estimated here is inconclusive.
To measure whether the domestication-associated bottleneck could have induced the rise of high-impact SNPs (hSNPs) in chicken genomes, we analyzed the variants called in domestic chicken and GGS genomes among our 1K CGP. We found that protein-coding regions accounted for ~4.2% of the chicken genome, and 1.6% of the genomic variants (435,919) were present in these exonic regions (Fig. 2a), which were nearly two times higher than those observed in other domestic animals including dogs, pigs, cattle, and horses (Additional file 1: Table S4). These exonic variants were only differentiated slightly between domestic chickens and GGS, suggesting that they have been subjected to evolutionary constraints. We classified mutations from the exonic regions into non-synonymous and synonymous substitutions and identified 146,193 non-synonymous SNPs, accounting for around 33.5% of the total exonic SNPs. The estimated ratio for the numbers of non-synonymous SNPs over exonic SNPs was similar to those observed in other domestic animals (Additional file 1: Table S4). To assess their potential effects (i.e., tolerant or deleterious) on associated amino acid changes in protein sequences of domestic chickens, we performed a PROVEAN  analysis. Based on the score threshold 2.5, we detected 22,282 potential hSNPs (Fig. 2b). Compared to mammals, bird chromosomes are highly variable in size. Chicken chromosomes are classified into three classes including 5 macrochromosomes (chrs: 15), 28 microchromosomes (chrs: 1138), and 4 intermediate chromosomes (chrs: 610) . We compared the PROVEAN scores of non-synonymous mutations and found that the average PROVEAN scores (damaging effect) of variants on the microchromosomes were significantly lower than those on the remaining chromosomes (Additional file 1: Figure S5). This finding is consistent with the previous report that microchromosomes have been subjected to evolutionary constraint or more efficient purifying selection because of their higher recombination rates , and therefore, mutations in conserved regions are more likely to be harmful.
The distribution and functional enrichment analyses of high-impact mutations. a Distribution of pairwise FST between domestic chickens and GGS for non-synonymous and synonymous mutations (stacked on the plot). b Distribution of the effects of variants predicted by PROVEAN. The more negative the score is, the more likely the variant impacts protein function. The PROVEAN score threshold used in this study is drawn as a vertical dashed line (score 2.5). c HPO analysis of genes carrying alleles with PROVEAN score < 10. P-values were corrected using Benjamini-Hochberg FDR. Count depicts the number of genes for each category. We only show HPO terms with more than six enriched genes
To evaluate the potential biological roles of the associated genes, we retrieved genes carrying the non-synonymous SNPs of PROVEAN score < 10 and performed functional enrichment analyses including GO and Human Phenotype Ontology (HPO). A total of 346 protein-coding genes were retrieved, and they are involved in multiple functional GO and HPO categories, including abnormalities of nervous system physiology, growth, bone and muscle development and morphology, cardiovascular and respiratory system, metabolism/homeostasis, vision, and immunity (Additional file 1: Table S5, Fig. 2c). These mutations were at low frequencies in domestic chickens, most of them are likely linked to health problems faced by modern poultry industries, as highly productive birds have been suffering from brittle bones, blindness, crippling leg disorders, ascites (a disease of the lungs and heart), and sudden death syndrome [52, 53]. Nevertheless, a few of them may be the target of positive selection during domestication and/or recent genetic improvement or breeding for specific traits.
In an early investigation , thyroid-stimulating hormone receptor (TSHR) showed the strongest signal of selection, with one missense mutation (chr5:40,089,599G/A; TSHR-Gly558Arg) being nearly fixed in domestic chickens compared to RJFs (< 23%; unclear subspecies classification). A recent paleogenetic study, however, showed the timing of selection on this gene in ancient and modern European chickens and concluded that the dramatic rise in frequency to modern ubiquity only began 1.1 kya . Our recent study showed that this mutation was nearly fixed (> 90%) in both indigenous chickens and GGS but maintained at extremely low frequencies among other RJF subspecies . Should any claims be based on the knowledge that this mutation is functional, however, the general biological role of this gene and the specific functional consequence of this mutation have not been resolved in domestic chickens. In our analysis, the TSHR-Gly558Arg has a PROVEAN score at 6.981, to be indicative of potentially high effect (< 2.5). Therefore, it is interesting to assess the potential biological function of this mutation as a potential proof of concept to test all our predictions.
Because of the challenge in editing an avian genome efficiently and precisely, several studies have employed transgenic mouse or human cell lines  or zebrafish [56, 57] models to test the potential roles of specific mutations of interest identified in the bird genomes. As TSHR is associated with development and metabolism in mice  and glycine at this position in chicken is conserved among all known vertebrate TSHR amino acid sequences [22, 59], we constructed chicken TSHR-558Arg knock-in mice (matched with mice TSHR-559Arg) to test whether this mutation has any biological effects (Additional file 1: Figure S6 and Table S6). At normal conditions, TSHR-559Arg homozygous mice developed significantly smaller (P < 0.01) bodies in both sexes than the wild-type mice (Fig. 3a, b, Additional file 1: Figure S7). At 30 C, 18 C, and 5 C experimental conditions, we measured the physical movements of the mice by counting their locomotor activities and found no significant difference (P > 0.05) between the TSHR-558Arg homozygous and wild-type mice (Fig. 3c). We also recorded their energy expenditures and metabolism rates and realized that the TSHR-559Arg homozygous mice had less food uptake (Additional file 1: Figure S8) and significantly lower oxygen (VO2), calorie consumptions, and carbon dioxide production (VCO2) than the wild-type mice (Fig. 3df; P < 0.05). This result suggests that TSHR-Gly558Arg is biologically functional in chickens. However, such validation for a single mutation cannot stand the effect of all mutations; further experimental validation for additional and specific variants is warranted.
Testing the function of TSHR-Gly559Arg using transgenic mouse model assay. a Photograph showing TSHR-559Arg knock-in homozygous (HO) and wild-type (WT) mice at 4 months old. b Bar plot shows that HO mice have significantly lower body weight than wild-type mice. c No difference in total locomotive ability between HO and wild-type mice. df HO mice have significantly lower oxygen consumption (VO2), calorie consumption, and carbon dioxide exhalation (VCO2) compared to wild-type mice. In b, n = 6 HO and n = 8 WT female and n = 8 HO and n = 8 WT male 4-week-old mice, as well as n = 7 HO and n = 7 WT female and n = 12 HO and n = 14 WT male 10-week-old mice were analyzed. In cf, n = 8 for both HO and WT male mice were analyzed for each test. *P < 0.05; **P < 0.01;***P < 0.001; ****P < 0.0001. Statistical significance was measured by Students t-test (two-tailed)
To compare the levels of genetic loads between domestic chickens and GGS, we evaluated the numbers and frequencies of non-synonymous and synonymous SNPs as well as the hSNPs among their genomes (Fig. 4). Our result showed that each chicken carried approximately 2.95% more hSNPs than GGS across their genomes (P = 0.01865, Wilcoxon signed-rank test; Fig. 4). Domestic chickens also had a significantly higher ratio of hSNPs relative to synonymous SNPs (P = 1.83e6, Wilcoxon signed-rank test; Fig. 4). In particular, the average allele frequency of hSNPs was significantly higher in domestic chickens than in GGS (P < 2.2e16, Wilcoxon signed-rank test; Fig. 4). Our previous study suggests that, after originating from GGS, domestic chickens were further admixed with other jungle fowls during their dispersal out the domestication center . The magnitude of gene flow is greatest between chickens and local jungle fowls, which might bias the estimation of genetic load. We further measured the number and ratio of hSNPs in some potentially drifted and/or isolated populations with no jungle fowl distributed in their natural ranges. To maximize more samples for each population, we chose Tibetan chicken, Beijing You chicken, Silkie chicken, chickens from Xinjiang province of China, and the White Leghorn chicken for comparison. The ratio of deleterious mutation relative to synonymous mutation and the level of heterozygous deleterious mutation varied among these chicken populations but were all higher than GGS (Additional file 1: Figure S9). Collectively, these analyses suggest that domestication has led to a rapid accumulation of high-impact mutations, and thus, the genetic burden/load defined by the hSNPs was likely increased in domestic chickens.
The frequency and number of high-impact mutations in domestic chickens and G. g. spadiceus. P-values were computed by the Wilcoxon signed-rank test between domestic chicken (DC; n = 696) and G. g. spadiceus (GGS; n = 35)
We next compared the levels of hSNPs in both homozygous and heterozygous states and observed 62.4% hSNPs in domestic chickens to be maintained in heterozygote states, significantly higher than that in GGS (57.8%; P = 0.00584, Wilcoxon signed-rank test; Fig. 4). In addition, domestic chickens carried far more heterozygous hSNPs (P = 0.00596, Wilcoxon signed-rank test) but less homozygous hSNPs (P = 0.0542, Wilcoxon signed-rank test; Fig. 4) than GGS (Fig. 4). However, the number of synonymous alleles, and these in the heterozygous states per genome, was comparable between domestic chickens and GGS (P = 0.5449 and 0.2239, Wilcoxon signed-rank tests). The total number of homozygous synonymous alleles was higher in GGS than in domestic chickens (P = 2.91e11, Wilcoxon signed-rank test; Fig. 4). Similarly, we measured the level of heterozygous hSNPs in Tibetan chicken, Beijing You chicken, Silkie chicken, chickens from Xinjiang province of China, and theWhite Leghorn chicken and found these populations also had a higher ratio and number of heterozygous hSNPs than GGS (Additional file 1: Figure S9). These results suggest that the heterozygous mutation load was elevated in domestic chickens.
How does selection affect the occurrence of hSNPs in domestic chicken genomes? To explore this, we retrieved the putatively selective sweeps identified by locus-specific branch length (LSBL) and -ratio from our previous study  and compared the distribution pattern of hSNPs mapped within these sweeps with that in the remaining chicken genomic regions. Each of three sets of selective sweeps defined by LSBL(chicken, GGS, G. g. jabouillei) or LSBL(chicken, GGS, G. g. murghi) or -ratio analysis possessed lower numbers of hSNPs (Additional file 1: Figure S10). This finding mirrors the observations in cassava  and grape , suggesting that the genes under selection tend to delimit hSNPs and/or to favor haplotypes carrying fewer hSNPs following the domestication and dispersal processes [60,61,62]. In addition, all the selective sweeps identified by each of the three statistics showed higher frequencies of hSNPs in domestic chickens than in GGS (Additional file 1: Figure S10). Some of these hSNPs may be the targets of selection to confer advantages in phenotypic or adaptive innovations, while most of them were likely a result of hitchhiking with nearby positively selected alleles.
Chickens are among the few domestic species with their progenitors extant in the wild today, providing an excellent system to address questions about evolutionary changes under domestication. In this work, we conducted systematic genomic studies of the domestication history and landscape of hSNPs using the largest genomic dataset from a worldwide sampling of indigenous chickens and their wild counterparts. Our analyses suggest that domestic chickens share a nearly identical demographic history with their direct wild ancestor, the GGS, before the Holocene. Around 12 kya, domestic chickens and GGS have diverged from each other, which is generally consistent with that assessed previously using MSMC based on 50% relative cross-coalescence rate (~9500 3300 years ago) . Subsequently, since domestication, domestic chickens experienced a decline in Ne that was 2.6 more severe than GGS, followed by a recovery towards population expansion. Yet, GGS evolved in a relatively different pattern within this period. We note that the divergence time between domestic chickens and GGS estimated using genomic data is slightly older than the archaeological recordings of chicken domestication; however, the estimated timing of the Ne reduction in domestic chickens generally corresponds with the hypothesized time frame of their domestication [8, 63, 64]. Interestingly, the patterns of Ne differ between domestic chickens and GGS since their split is similar to those observed in both African rice  and grape  from their wild progenitors, suggesting similar patterns of population size reduction and post-domestication introgression when domesticates spread into new ranges. Our results reveal that the chicken domestication process also followed the same model as what is observed in domestic animals like dogs  and horses , being initiated with a bottleneck and tailed by a recovery towards population expansion.
Our work reveals that domestic chickens carried 2.95% more hSNPs than GGS, a value comparable to those identified in dogs (2.6%)  and rice (34%) , but less than that in grape (~5.2%) . Domestic chickens also held a higher ratio of deleterious to synonymous SNPs and a higher frequency of hSNPs compared with GGS. It is possible that the profound historical Ne decline present in all Gallus gallus beginning ~80 kya may have induced the accumulation of hSNPs across all lineages at a comparable magnitude, but the domestication bottleneck and/or recent selection for genetic improvement dramatically increased the genetic load of domestic chickens. A similar pattern has already been observed in horses  and dogs . Our results support the cost of domestication hypothesis but challenge the proposal of no genetic load during chicken domestication [8, 19, 25, 68]; nonetheless, we could not completely rule out the potential effects from recent genetic improvement and introgression with other jungle fowls on this pattern.
We show that heterozygous hSNPs are accumulated more frequently in the genomes of domestic chickens than GGS, while homozygous ones display a contrary pattern. This is not unexpected, because most harmful mutations are at least partially recessive and therefore could only expose their damaging effects in homozygous states . Especially during breeding practices, harmful mutations in homozygous states are easily observed phenotypically, which promotes purging and breeding decisions, whereas such damaging alleles are masked in heterozygous states and thereby their transmission and accumulation would be facilitated. These results reveal the limitation of current breeding programs in effectively removing potentially damaging effects from the hSNPs while pursuing desirable economic traits. Our study highlights the importance of utilizing genomic information to safeguard genetic improvement through minimizing potential damaging mutations while effectively and sustainably utilizing this species for the poultry industry and biomedical research.
There are several potential caveats in this study. First, our 1K CGP initially aimed to infer the domestication history and evolution of chicken; there is a sampling bias in our study. Our sampling efforts initially focused on diverse and village chickens (which likely present as more ancient populations) from Asia (where RJF inhabited) and adjacent regions, while lacking samples from Africa, Oceania, and South America. Even though domestication bottleneck and increased hSNPs are observed in several chicken populations compared with their wild relatives, our samples cannot present the whole genetic diversity of all chickens across the world, and issues on the strength of bottleneck and the number and frequency of these hSNPs accumulated during the early domestication or recent genetic improvement of specific breeds could not be resolved based on our data. Also, there is pervasive gene flow between chickens and other jungle fowls, which also likely result in bias in our estimation of genetic load. Therefore, the magnitudes of bottleneck and genetic load underlying chicken domestication remain open; our analysis provides a result for further testing. Future work by exploring genomes from more heritage chicken lineages and breeds across the world and ancient samples spanning a wide range of periods are necessary to address these questions [67, 69,70,71]. Second, TSHR-559Arg homozygous mice displayed a significant difference in metabolism and development compared with the wild-type mice, suggesting that this mutation is biologically functional. This supports the early study that investigated the function of this mutation based on birds intercrossed between the ancestral RJF (wild type) and White Leghorn . Because of the profound divergence and potential genetic background difference between chickens and mice, we are not able to directly link any phenotypic changes in mice carrying the chicken allele to domestic chickens and RJFs. Our transgenic experiment provides a preliminary biological indicator to unlock TSHR function; however, whether it follows the same biological process in both chickens and mice remains unjustified. Third, despite the pattern of hSNPs in domestic chickens is generally consistent with the observations in other species, our genome coverages are relatively low for both domestic chickens and RJFs, and the levels of heterozygotes and het-hSNPs are likely underestimated. Further validation using higher coverage genomes is warranted. Lastly, our analysis focused on variants in the coding regions; however, non-coding regions are increasingly known to play important regulatory roles, and some variants within these regions likely have significant biological functions ; future studies should be designed to explore the evolutionary and functional roles of variants within regulatory regions in domestication and genetic improvement of chickens.
In conclusion, we systematically characterize the existence of a pre-domestication loss of genetic diversity followed by a domestication bottleneck in chickens, leading to the prominence of high-impact alleles across domestic chicken genomes. Through functional trait analyses, we suggest that these high-impact alleles affect behavior, development, and morphology, and our findings indicate that these alleles are partially under artificial selection pressure while the frequencies of detrimental variants are increased due to drift. This study presents a new page in chicken genomics, calling for a sharpened focus on the comparative genomic diversity of specific breeds and wild lineages, and for intensive functional analyses of high-impact alleles, to understand which contribute to domestication and genetic improvement of particular traits and which are maladaptive. This would enable the development of reliable markers for monitoring the concrete impact of genetic improvement and the purging of deleterious mutations on chicken genome evolution. In addition, our dating of the bottleneck and recovery processes in one of the most heavily relied upon domesticated species in the world has broad implications for understanding the biocultural interactions, translocation, and domestication practices affecting suites of species in Eurasia that were exploited in the past. Our study provides a possibility for further investigation using breeding experiments and a larger scale of genomes covering a wider sampling of global chickens and fossils.
In our 1K Chicken Genome Project (CGP), we leveraged the Illumina sequencing platform and generated 787 genomes from indigenous chickens and jungle fowls . These samples included domestic chickens (n = 620) and all five red jungle fowl subspecies (G. g. bankiva, n = 3; G. g. gallus, n = 6; G. g. murghi, n = 68; G. g. jabouillei, n = 27; and G. g. spadiceus, n = 45), as well as green jungle fowls (G. varius; n = 12), Ceylon jungle fowls (G. lafayettei; n = 4), and gray jungle fowls (G. sonnerati; n = 2). Specifically, G. g. spadiceus was sampled from Thailand and Yunnan province of China, and domestic chickens were sampled from villages in Indonesia, Thailand, Vietnam, China, India, Sri Lanka, Bangladesh, Pakistan, Iran, Afghanistan, and Europe. By combining an additional 76 published genomes [44, 56, 57, 74,75,76,77] and applying the standard BWA-GATK pipeline [78, 79], 33.4 M SNPs were successfully genotyped for 863 birds, of which ~25 million SNPs were identified in domestic chickens (n = 696) and G. g. spadiceus (n = 45). Genotypes for 9 G. g. spadiceus samples (ypt2887ypt2895) from Thailand and 1 G. g. spadiceus sample from Daweishan (ypt570) were admixed with chicken  and were removed. This resulting dataset (including 696 domestic chickens and 35 G. g. spadiceus samples) was used to perform the genetic diversity and genetic load analyses. The dataset is available at ChickenSD (http://bigd.big.ac.cn/chickensd/; released).
Pair-wise sequential Markovian coalescent (PSMC)  and multiple sequential Markovian coalescent (MSMC) analyses require high-coverage genomes for the successful calling of genome-wide heterozygosity. We selected high-coverage genomes from previous studies (find detail in Additional file 1: Table S1) [35, 40, 41, 74], including genomes for GGS and 18 diverse chicken populations (Yunnan chicken, Yunnan game fowl, Emei chicken, Muchuan chicken, Hetian chicken, Tulufan chicken, Lindian chicken, Liyang chicken, Xianju chicken, Baier Yellow chicken, Yunyang Da chicken, Laos chicken, Sri Lankan chicken, Ethiopian chicken, and four European commercial chicken breeds (White Recessive Rocks, Cobb chicken, White Leghorn, and Rhode Island Red)). All reads from these samples were mapped to the chicken reference genome (GRCg6a: https://www.ncbi.nlm.nih.gov/assembly/?term=GCA_000002315.5) using the standard BWA-GATK pipeline [78, 79]. Sequencing coverages for these genomes were calculated using samtools with the depth function .
PSMC , MSMC , and SMC++  were used to estimate the effective population size (Ne) changes in domestic chickens and GGS in the past. For PSMC analysis, consensus sequences of each of the individuals were called using samtools with the mpileup command (version: 1.3.1; http://samtools.sourceforge.net/). The loci with less than 1/3 or more than 2 times average read depths were deleted, and sites with consensus qualities below 20 were also removed. PSMC was running with parameters set as psmc -N25 -t15 -r5 -p 4+25*2+4+6. Input data for MSMC was prepared using the tool generate_multihetsep.py suggested by the author from https://github.com/stschiff/msmc-tools. The genotypes for all samples were phased jointly using Beagle V4.1  with default parameters. For each group, two individuals (four haplotypes) were analyzed.
For running SMC++ (v1.15.2), we sequenced genomes for each of the three GGS samples (IDs ypt3001, ypt3006, and ypt3009) reported  previously to coverage over 20-folds. We performed analysis for the regions with reads mapped uniquely that were generated using the SNPable toolkit (http://lh3lh3.users.sourceforge.net/snpable.shtml) with settings - k=35 and r=0.9. To maximize more populations to be analyzed, five genomes for each population with coverage over 15-folds were used. Input file for SMC++ was generated using the pipeline as the author suggested (https://github.com/popgenmethods/smcpp). Except that Laos chicken, Emei chicken, and Muchuan chicken have less than five genomes with sequencing depth over 15-folds, we analyzed all populations that were analyzed by MSMC and PSMC above. We further included Jingyang chicken and Pengxia chicken for the SMC++ analysis. SMC++ was ran using default parameters.
Finally, we investigated the population histories by analyzing the joint allele frequency spectra using diffusion approximation for demographic inference (dadi) . Because we were mostly interested in the joint demographic history of domestic chickens and GGS, we selected a total of 40 genomes (20 for each group; IDs for GGS: 18833, 19912, Ypt570, Xcelris_174, ypt3003, ypt2893_L3_I025, Xcelris_176, ypt3047, ypt2895_L3_I026, ypt2889, ypt3008, ypt3051, ypt3007, ypt3038, ypt3069, ypt3006, ypt3042, ypt3002, ypt2894, and ypt2887; IDs for domestic chickens: YPt648, Ypt638, 43S, Ypt646, ypt3180, ypt2656, 95S_L8_I025, Ypt606, 19S_L4_I026, 87S_L5_I010, ypt948_L2_I034, Ypt645, 77S_L4_I029, ypt910_L3_I005, 88S_L4_I011, 44S_L4_I001, 130S_L4_I044, ypt907_L6_I002, 39S_L6_I053, and 21S_L6_I028) from the 1K CGP. To avoid evolutionary restrictions as much as possible, we excluded coding regions. We also masked the repeated (annotations from NCBI: https://www.ncbi.nlm.nih.gov/) and low-complexity regions identified using mdust . Finally, 47,307 autosomal regions of at least 1 kb spanning a total of 70,919,324 bp were used for the demographic analysis. We computed two-dimensional site frequency spectra using ANGSD , as described previously . We examined four demographic models (Additional file 1: Figure S3): (A) constant without gene flow, (B) constant with asymmetric gene flow, (C) constant-growth/reduction with asymmetric migrations, and (D) constant-growth/reduction with asymmetric migrations. For each model, we ran three sets of increasingly focused optimizations before performing the final model selection. Models were compared using the Akaike Information Criterion (AIC), and the replicate with the highest likelihood for each model was used to calculate AIC and deltAIC. To calculate the confidence interval for the parameters in our best-fitting model, we applied non-parametric bootstrapping (100 replicates).
Estimations from PSMC, MSMC, SMC++, and dadi were scaled using a generation time (g) of 1 year and a mutation rate () of 1.91 109 substitutions per site per year . We used VCFtools  to average the population-based nucleotide diversity ()  in domestic chickens and GGS (--window-pi 50000 --window-pi-step 25000).
To examine the evolution of hSNPs in chickens before and after their domestication, we followed a similar pipeline as described previously [60, 61] to analyze the 33.4 M SNPs called from the 863 genomes. First, we retrieved non-synonymous mutations as annotated by ANNOVAR  and searched the chicken genome annotations from the ENSEMBL database (version 83: http://dec2015.archive.ensembl.org/index.html). The ancestral state of a variant was inferred from the green jungle fowl. To predict the effect of a missense mutation on a protein, we applied the PROVEAN software  in searching the non-redundant protein database (download from NCBI: https://www.ncbi.nlm.nih.gov/). The prediction was based on evolutionary conservation by comparing the query and target sequences. Similar to the early study , a mutation with a PROVEAN score less than 2.5 was considered to be harmful, and such kinds of variants were labeled as hSNPs.
To obtain a global perspective on the functions of genes carrying such hSNPs, we used g:Profiler  to retrieve the functional enrichment terms, including Gene Ontology (GO, KEGG pathways) and Human Phenotype Ontologies (HPOs). To assess the landscape of genetic loads over chicken domestication, we calculated the number and frequency of hSNPs per individual or region and compared them with those of synonymous mutations.
Furthermore, we retrieved genomic regions of putatively selective sweeps that were measured by locus-specific branch length (LSBL) statistics  in the combination of LSBL1(chicken; G. g. spadiceus, G. g. jabouillei) and LSBL2 (chicken; G. g. spadiceus, G. g. murghi), as well as -ratio (G.g.spadiceus/chicken)  from our previous study . For sweep regions identified by each of the three statistics, we compared the number and frequency of hSNPs within the sweeps to the remaining genomic regions between domestic chickens and GGS.
The allele TSHR-Gly558 (chr5:40,089,599G) in domestic chickens is highly conserved across vertebrates and corresponds to the mice-TSHR-Gly559 (c.1675G) in the 10th exon of transcript Tshr-202 (http://www.ensembl.org/Mus_musculus/Transcript/Exons?db=core;g=ENSMUSG00000020963;r=12:9140 ;t=ENSMUST00000021346). A C57BL/6 mouse model with a mutation at the mouse TSHR locus (p. Gly559Arg; c.1675G>A) was constructed by CRISPR/Cas-mediated genome engineering (Shanghai Biomodel Organism Science & Technology Development Co., Ltd). Briefly, Cas9 mRNA, gRNA, and donor DNA were micro-injected into the fertilized eggs of C57BL/6J mice to obtain F0 generation mice with the mutation of the target site (Additional file 1: Figure S5 and Table S6). The F0 generation mice were mated with C57BL/6J mice to obtain positive and homozygous F1 generation mice. All mice had free access to food and water. All experiments were performed following the Health Guide for the Care and Use of Laboratory Animals and were approved by the Ethics Committee of the Kunming Institute of Zoology, CAS.
A Comprehensive Laboratory Animal Monitoring System (CLAMS) was used to monitor and analyze the indexes of metabolism and feed intake of the transgenic mice. Eight-week-old male mice were weighed (n = 8*2) and placed in CLAMS (PRO-MRR-8) to measure the metabolism of homozygous (HO) and wild-type mice at 30 C, 18 C, and 5 C for 72 h. The levels of oxygen consumption (VO2), carbon dioxide exhalation (VCO2), calorie consumption, and water and food intake were recorded every 5 min for each mice (including HO and wild type). All mice had free access to water and food and were subjected to the same day-night cycle during the examination. Statistical significance was measured by Students test (two-tailed), and P < 0.05 was accepted to be significant.
All data generated or analyzed during this study are included in this published article and its supplementary information files. Information for the published dataset for estimating demographic histories is available in Additional file 1: Table S1. The genotype data we analyzed (in VCF format) and three GGS genomes we generated were available at ChickenSD (http://bigd.big.ac.cn/chickensd/).
Makino T, Rubin CJ, Carneiro M, Axelsson E, Andersson L, Webster MT. Elevated proportions of deleterious genetic variation in domestic animals and plants. Genome Biol Evol. 2018;10(1):27690 https://doi.org/10.1093/gbe/evy004.
Gro C, Bortoluzzi C, de Ridder D, Megens H-J, Groenen MAM, Reinders M, et al. Evolutionarily conserved non-protein-coding regions in the chicken genome harbor functionally important variation. bioRxiv. 2020; https://doi.org/10.1101/2020.03.27.012005.
Carneiro M, Rubin CJ, Di Palma F, Albert FW, Alfoldi J, Martinez Barrio A, et al. Rabbit genome analysis reveals a polygenic basis for phenotypic change during domestication. Science (New York, NY). 2014;345(6200):10749 https://doi.org/10.1126/science.1253714.
Gerbault P, Allaby RG, Boivin N, Rudzinski A, Grimaldi IM, Pires JC, et al. Storytelling and story testing in domestication. Proc Natl Acad Sci U S A. 2014;111(17):615964 https://doi.org/10.1073/pnas.1400425111.
Alberto FJ, Boyer F, Orozco-terWengel P, Streeter I, Servin B, de Villemereuil P, et al. Convergent genomic signatures of domestication in sheep and goats. Nat Commun. 2018;9(1):813 https://doi.org/10.1038/s41467-018-03206-y.
Schubert M, Jonsson H, Chang D, Der Sarkissian C, Ermini L, Ginolhac A, et al. Prehistoric genomes reveal the genetic foundation and cost of horse domestication. Proc Natl Acad Sci U S A. 2014;111(52):E56619 https://doi.org/10.1073/pnas.1416991111.
Marsden CD, Ortega-Del Vecchyo D, OBrien DP, Taylor JF, Ramirez O, Vila C, et al. Bottlenecks and selective sweeps during domestication have increased deleterious genetic variation in dogs. Proc Natl Acad Sci U S A. 2016;113(1):1527 https://doi.org/10.1073/pnas.1512501113.
Nabholz B, Sarah G, Sabot F, Ruiz M, Adam H, Nidelet S, et al. Transcriptome population genomics reveals severe bottleneck and domestication cost in the African rice (Oryza glaberrima). Mol Ecol. 2014;23(9):221027 https://doi.org/10.1111/mec.12738.
Koenig D, Jimenez-Gomez JM, Kimura S, Fulop D, Chitwood DH, Headland LR, et al. Comparative transcriptomics reveals patterns of selection in domesticated and wild tomato. Proc Natl Acad Sci U S A. 2013;110(28):E265562 https://doi.org/10.1073/pnas.1309606110.
Lu J, Tang T, Tang H, Huang J, Shi S, Wu CI. The accumulation of deleterious mutations in rice genomes: a hypothesis on the cost of domestication. Trends Genet. 2006;22(3):12631 https://doi.org/10.1016/j.tig.2006.01.004.
Frantz LA, Larson G. A genetic perspective on the domestication continuum. In: Hybrid communities: biosocial approaches to domestication and other trans-species relationships: Taylor & Francis; 2018. http://qmro.qmul.ac.uk/xmlui/handle/123456789/53406.
Frantz LA, Schraiber JG, Madsen O, Megens HJ, Cagan A, Bosse M, et al. Evidence of long-term gene flow and selection during domestication from analyses of Eurasian wild and domestic pig genomes. Nat Genet. 2015;47(10):11418 https://doi.org/10.1038/ng.3394.
Wallberg A, Han F, Wellhagen G, Dahle B, Kawata M, Haddad N, et al. A worldwide survey of genome sequence variation provides insight into the evolutionary history of the honeybee Apis mellifera. Nat Genet. 2014;46(10):10818 https://doi.org/10.1038/ng.3077.
Rubin CJ, Zody MC, Eriksson J, Meadows JR, Sherwood E, Webster MT, et al. Whole-genome resequencing reveals loci under selection during chicken domestication. Nature. 2010;464(7288):58791 https://doi.org/10.1038/nature08832.
Bortoluzzi C, Bosse M, Derks MFL, Crooijmans R, Groenen MAM, Megens HJ. The type of bottleneck matters: insights into the deleterious variation landscape of small managed populations. Evol Appl. 2020;13(2):33041 https://doi.org/10.1111/eva.12872.
Guo X, He XX, Chen H, Wang ZC, Li HF, Wang JX, et al. Revisiting the evolutionary history of domestic and wild ducks based on genomic analyses. Zool Res. 2021;42(1):4350. https://doi.org/10.24272/j.issn.2095-8137.2020.133.
Fan Z, Silva P, Gronau I, Wang S, Armero AS, Schweizer RM, et al. Worldwide patterns of genomic variation and admixture in gray wolves. Genome Res. 2016;26(2):16373. https://doi.org/10.1101/gr.197517.115.
Guo X, Wang ZC, Wang S, Li HF, Suwannapoom C, Wang JX, et al. Genetic signature of hybridization between Chinese spot-billed ducks and domesticated ducks. Anim Genet. 2020;51(6):86675 https://doi.org/10.1111/age.13002.
Wang MS, Wang S, Li Y, Jhala Y, Thakur M, Otecko NO, et al. Ancient hybridization with an unknown population facilitated high-altitude adaptation of canids. Mol Biol Evol. 2020;37(9):261629 https://doi.org/10.1093/molbev/msaa113.
Groenen MA, Archibald AL, Uenishi H, Tuggle CK, Takeuchi Y, Rothschild MF, et al. Analyses of pig genomes provide insight into porcine demography and evolution. Nature. 2012;491(7424):3938 https://doi.org/10.1038/nature11622.
Nadachowska-Brzyska K, Burri R, Smeds L, Ellegren H. PSMC analysis of effective population sizes in molecular ecology and its application to black-and-white Ficedula flycatchers. Mol Ecol. 2016;25(5):105872 https://doi.org/10.1111/mec.13540.
Luo W, Luo C, Wang M, Guo L, Chen X, Li Z, et al. Genome diversity of Chinese indigenous chicken and the selective signatures in Chinese gamecock chicken. Sci Rep. 2020;10(1):14532. https://doi.org/10.1038/s41598-020-71421-z.
Li D, Li Y, Li M, Che T, Tian S, Chen B, et al. Population genomics identifies patterns of genetic diversity and selection in chicken. BMC Genomics. 2019;20(1):263 https://doi.org/10.1186/s12864-019-5622-4.
Nadachowska-Brzyska K, Li C, Smeds L, Zhang G, Ellegren H. Temporal dynamics of avian populations during Pleistocene revealed by whole-genome sequences. Curr Biol. 2015;25(10):137580 https://doi.org/10.1016/j.cub.2015.03.047.
Bosse M, Megens HJ, Madsen O, Frantz LA, Paudel Y, Crooijmans RP, et al. Untangling the hybrid nature of modern pig genomes: a mosaic derived from biogeographically distinct and highly divergent Sus scrofa populations. Mol Ecol. 2014;23(16):4089102 https://doi.org/10.1111/mec.12807.
Gutenkunst RN, Hernandez RD, Williamson SH, Bustamante CD. Inferring the joint demographic history of multiple populations from multidimensional SNP frequency data. PLoS Genet. 2009;5(10):e1000695 https://doi.org/10.1371/journal.pgen.1000695.
Axelsson E, Webster MT, Smith NG, Burt DW, Ellegren H. Comparison of the chicken and turkey genomes reveals a higher rate of nucleotide divergence on microchromosomes than macrochromosomes. Genome Res. 2005;15(1):1205. https://doi.org/10.1101/gr.3021305.
Loog L, Thomas MG, Barnett R, Allen R, Sykes N, Paxinos PD, et al. Inferring allele frequency trajectories from ancient DNA indicates that selection on a chicken gene coincided with changes in medieval husbandry practices. Mol Biol Evol. 2017;34(8):198190 https://doi.org/10.1093/molbev/msx142.
Pan S, Lin Y, Liu Q, Duan J, Lin Z, Wang Y, et al. Convergent genomic signatures of flight loss in birds suggest a switch of main fuel. Nat Commun. 2019;10(1):2756 https://doi.org/10.1038/s41467-019-10682-3.
Wang MS, Zhang RW, Su LY, Li Y, Peng MS, Liu HQ, et al. Positive selection rather than relaxation of functional constraint drives the evolution of vision during chicken domestication. Cell Res. 2016;26(5):55673 https://doi.org/10.1038/cr.2016.44.
Wang MS, Huo YX, Li Y, Otecko NO, Su LY, Xu HB, et al. Comparative population genomics reveals genetic basis underlying body size of domestic chickens. J Mol Cell Biol. 2016;8(6):54252 https://doi.org/10.1093/jmcb/mjw044.
Grottesi A, Gabbianelli F, Valentini A, Chillemi G. Structural and dynamic analysis of G558R mutation in chicken TSHR gene shows altered signal transduction and corroborates its role as a domestication gene. Anim Genet. 2020;51(1):517 https://doi.org/10.1111/age.12880.
Ramu P, Esuma W, Kawuki R, Rabbi IY, Egesi C, Bredeson JV, et al. Cassava haplotype map highlights fixation of deleterious mutations during clonal propagation. Nat Genet. 2017;49(6):95963 https://doi.org/10.1038/ng.3845.
Zhou Y, Massonnet M, Sanjak JS, Cantu D, Gaut BS. Evolutionary genomics of grape (Vitis vinifera ssp. vinifera) domestication. Proc Natl Acad Sci U S A. 2017;114(44):1171520 https://doi.org/10.1073/pnas.1709257114.
He F, Pasam R, Shi F, Kant S, Keeble-Gagnere G, Kay P, et al. Exome sequencing highlights the role of wild-relative introgression in shaping the adaptive landscape of the wheat genome. Nat Genet. 2019;51(5):896904 https://doi.org/10.1038/s41588-019-0382-2.
Peters J, Lebrasseur O, Best J, Miller H, Fothergill T, Dobney K, et al. Questioning new answers regarding Holocene chicken domestication in China. Proc Natl Acad Sci U S A. 2015;112(19):E2415 https://doi.org/10.1073/pnas.1503579112.
Meyer RS, Choi JY, Sanches M, Plessis A, Flowers JM, Amas J, et al. Domestication history and geographical adaptation inferred from a SNP map of African rice. Nat Genet. 2016;48(9):10838 https://doi.org/10.1038/ng.3633.
Wang GD, Zhai W, Yang HC, Wang L, Zhong L, Liu YH, et al. Out of southern East Asia: the natural history of domestic dogs across the world. Cell Res. 2016;26(1):2133 https://doi.org/10.1038/cr.2015.147.
Fages A, Hanghoj K, Khan N, Gaunitz C, Seguin-Orlando A, Leonardi M, et al. Tracking five millennia of horse management with extensive ancient genome Time Series. Cell. 2019;35(7):4735 https://doi.org/10.1016/j.cell.2019.03.049.
Librado P, Gamba C, Gaunitz C, Der Sarkissian C, Pruvost M, Albrechtsen A, et al. Ancient genomic changes associated with domestication of the horse. Science (New York, NY). 2017;356(6336):4425 https://doi.org/10.1126/science.aam5298.
Karlsson AC, Fallahshahroudi A, Johnsen H, Hagenblad J, Wright D, Andersson L, et al. A domestication related mutation in the thyroid stimulating hormone receptor gene (TSHR) modulates photoperiodic response and reproduction in chickens. Gen Comp Endocrinol. 2016;228:6978 https://doi.org/10.1016/j.ygcen.2016.02.010.
Liu S, Yu Y, Zhang S, Cole JB, Tenesa A, Wang T, et al. Epigenomics and genotype-phenotype association analyses reveal conserved genetic architecture of complex traits in cattle and human. BMC Biol. 2020;18(1):80 https://doi.org/10.1186/s12915-020-00792-6.
Wang MS, Li Y, Peng MS, Zhong L, Wang ZJ, Li QY, et al. Genomic analyses reveal potential independent adaptation to high altitude in Tibetan chickens. Mol Biol Evol. 2015;32(7):18809 https://doi.org/10.1093/molbev/msv071.
Yi G, Qu L, Liu J, Yan Y, Xu G, Yang N. Genome-wide patterns of copy number variation in the diversified chicken genomes using next-generation sequencing. BMC Genomics. 2014;15(1):962. https://doi.org/10.1186/1471-2164-15-962.
Wang MS, Otecko NO, Wang S, Wu DD, Yang MM, Xu YL, et al. An evolutionary genomic perspective on the breeding of dwarf chickens. Mol Biol Evol. 2017;34(12):30818 https://doi.org/10.1093/molbev/msx227.
McKenna A, Hanna M, Banks E, Sivachenko A, Cibulskis K, Kernytsky A, et al. The Genome Analysis Toolkit: a MapReduce framework for analyzing next-generation DNA sequencing data. Genome Res. 2010;20(9):1297303. https://doi.org/10.1101/gr.107524.110.
Li H, Handsaker B, Wysoker A, Fennell T, Ruan J, Homer N, et al. The Sequence Alignment/Map format and SAMtools. Bioinformatics (Oxford, England). 2009;25(16):20789 https://doi.org/10.1093/bioinformatics/btp352.
Danecek P, Auton A, Abecasis G, Albers CA, Banks E, DePristo MA, et al. The variant call format and VCFtools. Bioinformatics (Oxford, England). 2011;27(15):21568 https://doi.org/10.1093/bioinformatics/btr330.
Shriver MD, Kennedy GC, Parra EJ, Lawson HA, Sonpar V, Huang J, et al. The genomic distribution of population substructure in four populations using 8,525 autosomal SNPs. Hum Genomics. 2004;1(4):27486 https://doi.org/10.1186/1479-7364-1-4-274.
We thank Laurent A. F. Frantz and Greger Larson for their valuable comments on this study. We thank Jing-Fang Si for his help with the SMC++ analysis. We also thank Shao-Bin Xu and Xiu-Zhen Yang from the High-Performance Computing Center at Kunming Institute of Zoology, CAS, for their support on the computational analyses.
This work was supported by the National Natural Science Foundation of China (31771415, 31801054, U1902204, 31822048, and 31771405), the Strategic Priority Research Program of the Chinese Academy of Sciences (CAS, XDA2004010301), and the West Light Foundation of CAS (Y902401081). C.S. also thanks to the support of the Unit of Excellence 2021 on Biodiversity and Natural Resources Management, University of Phayao, Thailand. The Youth Innovation Promotion Association of CAS also provided support to M.-S.W. Animal Branch of the Germplasm Bank of Wild Species of CAS (the large research infrastructure funding) also supported this project. The Chinese Governments contribution to CAAS-ILRI Joint Laboratory on Livestock and Forage Genetic Resources in Beijing (2021-YWF-ZX-02) is appreciated. K.-X.Q was supported by the Young and Middle-aged Academic Technology Leader Backup Talent Cultivation Program in Yunnan Province (2018HB045). This publication has been prepared within the framework of the UNEP/GEF project Development and application of decision-support tools to conserve and sustainably use genetic diversity in indigenous livestock and wild relatives and it contributes to the CGIAR Research Program on Livestock.
Ming-Shan Wang,Jin-Jin Zhang,Sheng Wang,Min-Sheng Peng,Mukesh Thakur,Ali Esmailizadeh,Nalini Yasoda Hirimuthugoda,Lin Zeng,Ting-Ting Yin,Min-Min Yang,Ming-Li Li,Xue-Mei Lu,Shao-Hong Feng,Guojie Zhang,Dong-Dong Wu&Ya-Ping Zhang
Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, The Cooperative Innovation Center for Sustainable Pig Production, Ministry of Education, Huazhong Agricultural University, Wuhan, 430070, China
Laboratory of Animal Genetics, Breeding and Reproduction, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Ministry of Agriculture of China, Beijing, 100193, China
Y.-P.Z., J.-L.H., D.-D.W., M.-S.W., and Y.J. conceived the project and designed the research. M.-S.W., X.G., H.A., Z.-Q.Z., S.W., L. Z., S.-H.F., and M.L. performed the analysis. J.-J.Z. and M.-M.Y. conducted the wet lab experiments. X.-M.L., M.K., J.-L.H., A.E., K.-X.Q., C.S., N.Y.H., H.A., S.S., M.S.A.Z., S.K., S. S., H.K.-K., E.L., S.C., H.G.T.N.G., T.M.S., H.Z., A.K.F.H. B., M.S.K., G.L.L.P.S., T.-T. Y., Y.-M.W., O.A.M., and M.N.M.I. did the sample collection, prepared the DNA samples, and contributed genome sequencing data for 1K CGP. M.-S.W., J.-L.H., H.A., M.B., and R.M. drafted the manuscript with input from all authors. J.-L.H., M.B., R.M., Y.-P.Z., D.-D.W., M.-S.W., O.H., and A.E. revised the manuscripts. All authors read and approved the final manuscript.
Nucleotide diversity for G. g. spadiceus and chicken populations (grouped by samling locations and breeds). Figure S2. Demographic histories for G. g. spadiceus and diverse chicken groups by PSMC. A total of 18 chicken populations were included in this analysis. Figure S3. Four tested demographic models for dadi analysis. Nanc, ancestral population size before the split; T, timepoints; m, migrations; Napop, ancestral population size after split. Ncpop, current population size. Arrows depict migration directions. Figure S4. Comparing observed data and model allele frequency spectrum for the best model (Model 3). Figure S5. Provean-scores for nonsynonymous mutations (for all mutations, left; and for mutations with Provean-scores 2.5, right) in microchromosomes, macrochromosomes, and intermediate chromosomes. Figure S6. Pipeline for constructing the mouse model with a mutation at the mouse TSHR locus (p. Gly559Arg; c.1675G>A). Figure S7. Photograph showing TSHR-559Arg knock-in homozygous (HO) and wild-type mice at 10 months old. Figure S8. Gly558Arg knock-in mice consumed less food than wild-type. *, P<0.05. Statistical significance was measured by the Students t test. N=8 for both HO and wild-type male mice were used in each test. Figure S9. Number and ratio of high-impact mutations among chicken populations. GGS, G. g. spadiceus; DC, all domestic chickens; WL, White Leghorn; TC, Tibetan chicken, XJ, Xinjiang local chicken; You; Beijing You chicken. Figure S10. Number and frequency of deleterious mutations in the genomic regions of putatively selective sweeps. Table S1. Information for high-coverage genomes used for PSMC, MSMC, and SMC++ analyses. Table S2. Estimations of likelihoods and AIC scores from four demographic models. Table S3. Summary of population histories calculated from 2DSFS. Confidence intervals (95%) were obtained by bootstrapping all sites and performing parameter inference on each bootstrap dataset with 100 runs. Table S4. Distribution of variants identified in dog, sheep, goat, cattle, pig, and horse. This data is from our previous publication. Table S5. GO enrichment for genes carrying nonsynonymous mutation with provean-score of <10. Table S6. Guide RNA sequences for the exon 10 of mouse-TSHR.
Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.
Wang, MS., Zhang, JJ., Guo, X. et al. Large-scale genomic analysis reveals the genetic cost of chicken domestication. BMC Biol 19, 118 (2021). https://doi.org/10.1186/s12915-021-01052-x
By using this website, you agree to our Terms and Conditions, California Privacy Statement, Privacy statement and Cookies policy. Manage cookies/Do not sell my data we use in the preference centre.
Staying updated about Political and Social issues is paramount to successfully running your business. Politics can affect economic conditions, regulations, socio-cultural environments, and even technologies used in enterprises. On the other hand, social issues like global warming, gender equality, employment laws, social networking trends, and health awareness can affect the brand name of a business and customer choices.
One impact of political decisions are business tax. A government can choose to increase taxes for some companies while decreasing taxes for others. During elections, some political parties may campaign to reduce taxes for business owners while other parties may favor middle-class people over business owners.
A plethora of factors like Tariff, Bureaucracy Control, and Data Law impacts business decisions. When conducting business activities overseas (multinational), then business owners have no choice but to adhere to the policies made by the ruling party. To outrank competitors, their every action would be around a new set of framed policies dependent on their geographic location.
An example of this is the recent introduction of the Goods and Services Tax in India, which saw many small and medium businesses get adversely affected. For instance, GST has negatively impacted the real estate sector by adding almost 8% to the cost of newly constructed homes by raising taxes on raw material, which has led to a decrease in demand for new homes by nearly 12%.
Apart from taxes, politics can also affect the interest rates of the economy, which can change the borrowing power of companies. For the sake of your business, you should be aware of the political decision-making of the relevant government concerning economic policies.
Politics drives the regulations and laws for businesses. Governments view businesses as essential vehicles of socio-economic change within the state or the country. To protect the public interest, governments pass legislation that impacts the way a business operates. Government laws and regulations affect the relationship between customer and company, employment policies, and define boundaries for suppliers.
Many times these stringent regulations can hinder business growth. E.g., Banning the import of certain products from overseas could cause trouble for a manufacturing unit as this product could be one of the raw material constituents like chemicals for manufacturing cement, adhesive, etc. Companies should be equipped with other alternate materials, which may prevent further losses and their brand image from getting tarnished.
Policy decisions can also have significant effects on the barriers to entry for international businesses looking to expand into markets, directly affecting foreign direct investments and, ultimately, the strength of the economy as a whole.
A business should be aware of the changes in the compliance laws, data protection laws, health and safety laws, discrimination laws, trade union laws, consumer protection laws, online selling laws and intellectual property rights laws. Politics can determine the minimum wage businesses are required to pay employees for employment in specific locations. Businesses may have to allocate more budget for healthcare policies for employees, depending on the regulation.
The politics of countries overseas is essential for companies carrying out international trade. A business operating in multiple states should be aware of any political changes that can affect the import-export restrictions on the quality and quantity of the product. Policies like Brexit, the UK departure from the EU, can impact the way trade happens for customers in the UK and in the EU. A lack of political stability in countries overseas can jeopardize the prospects of business in those countries.
When a company operates overseas, then they expect support from the government by them providing ease of business. But due to certain insurmountable circumstances, the government can withdraw its support or create policies to achieve specific objectives, such as encouraging imports/exports or protecting local businesses/communities.
For example, the Kenyan government banned the export of avocados because international demand drove the price too high for locals to afford readily-available food. Farmers suffered financially (as they had to sell locally at a very reduced rate), but the people prospered., which can cause a setback to the business.
Some examples include civil wars in Sri Lanka, Egypt, and Syria. When a government gets overthrown in a country, companies are subject to rioting, looting involving monetary loss and loss of life. When elections take place in other countries and when the political situation changes, dealing with consumers and suppliers in those countries can either become simpler or become more difficult.
Today, a majority of businesses have to stand the test of the way they treat the earth. Sustainable growth is of high importance. Consumers are looking for brands that are environment-friendly. Businesses that cause pollution or add to the problems of global climate change do not last long. Even governments are imposing substantial financial penalties on companies that are not taking care of environmental and social issues seriously.
Even a minor change in environmental policies can significantly impact businesses. Companies are bound to spend a vast amount of money on waste disposal due to these stringent laws that can hover over any time. To avoid such a situation, tech giants like Apple are making their products 100% BPA free and recyclable. But the cost incurred to make such changes happen was substantial.
Businesses using toxic chemicals in their products, food manufacturers that use slash and burn agricultural practices, and factories that cause water pollution are all facing protests from society. Therefore, for your business growth, you should be aware of the latest trends in society related to the best environmental practices.
Almost all countries have now made it mandatory for large to medium size businesses to participate in corporate social responsibility (CSR). To run a successful business, you need to protect your companys image by keeping society at the forefront of decision making.
Every nation has a unique set of CSR measures, and companies are liable to contribute to such responsibilities. In laymans terms, its an art of giving back to society. Such CSR events help in creating an overall brand image that contributes to the longevity of the business. CSR events are like a social blueprint that leaves a positive impression in the minds of other companies and customers.
Businesses can also include their employees and suppliers in their CSR measures by providing them with adequate facilities that can improve their quality of life. Today, businesses are no longer praised for considering and positively contributing to environmental and social issues. Theyre expected to.
Due to political and social issues, the role of work has evolved everywhere. Work used to be a subject of survival and need, but it has changed. The structure of the workforce has grown. Work is now a matter of personal satisfaction. Work-life balance is a crucial point at the social and political level in business.
Political and social issues have impacted companies in increasing their engagement in personal, family, and work issues. Other than the work-life balance, perks like company care, free flights, flexible working hours, and a four-day week work culture started becoming common. These perks helped in motivating, retaining, and attracting an excellent workforce.
Social and Political issues can impact a business immensely. Being a passionate entrepreneur or having a great product may not be enough. If you are not aware of the social and political environment around you, your business runs a risk of being a setback. Reading and learning about the latest trends will help keep your business up and running.Get in Touch with Mechanic