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1.
The North China Plain (NCP), one of the most important agricultural regions in China, is facing a major water-resource crisis evoked by excessive exploitation of groundwater. To reduce water use while maintaining high crop production level, improving variety water use efficiency (WUE) is an urgent need, especially because other water-saving measures such as water delivery, irrigation, and agricultural practices have already achieved most possible progresses. Evaluation of variety WUE can be performed accurately at the individual plant level (WUEp). Reviewing the studies on physiological factors affecting WUE p performed up to date, stomatal conductance was considered to be an important trait associating closely with WUE p . The trait showed a large degree of varietal variability under well-watered conditions. Crop varieties differ highly in sensitivity of stomata to soil and air drying, with some varieties strongly reducing their stomatal conductance in contrast with those lightly regulating their stomata. As a result, difference among varieties in WUE p was enlarged under water deficit conditions in contrast with those under well-watered conditions. The relationship between stomatal conductance and yield depends on water availability of whole growing period in local areas. Usually, large stomatal conductance results in a high yield under good irrigation system, whereas a low stomatal conductance can lead to yield benefit under limited stored soil moisture conditions. In the NCP, winter wheat is the largest consumer of irrigation water, improvement strategies for high WUE aiming at wheat crops are in urgent need. We suggest, for the well-irrigated areas with excessive exploitation of groundwater, the wheat breeding program need to combine medium stomatal conductance (0.35 mmol H2O m-2 s-1 or so), high carboxylation efficiency, and high harvest index. Areas with partial/full access to irrigation, or infrequent drought, should target wheat varieties with high stomatal conductance under no water stress and low sensitivity of stomata to soil water deficit. Drought-prone rain-fed areas characterized by frequent and long terminal drought should target wheat varieties with low stomatal conductance under no water stress and high stomata sensitivity to soil drying to make water available during grain filling.  相似文献   

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Urban agriculture in Cuba has rapidly become a significant source of fresh produce for the urban and suburban populations. A large number of urban gardens in Havana and other major cities have emerged as a grassroots movement in response to the crisis brought about by the loss of trade, with the collapse of the socialist bloc in 1989. These gardens are helping to stabilize the supply of fresh produce to Cuba's urban centers. During 1996, Havana's urban farms provided the city's urban population with 8,500 tons of agricultural produce, 4 million dozens of flowers, 7.5 million eggs, and 3,650 tons of meat. This system of urban agriculture, composed of about 8,000 gardens nationwide has been developed and managed along agroecological principles, which eliminate the use of synthetic chemical pesticides and fertilizers, emphasizing diversification, recycling, and the use of local resources. This article explores the systems utilized by Cuba's urban farmers, and the impact that this movement has had on Cuban food security.  相似文献   

4.
The primary focus of agricultural research and extension in eastern Africa is technology generation and dissemination. Despite prior critiques of the shortcomings of this approach, the consequences of such activities continue to be measured through the number of technologies developed and introduced into the supply chain. At best, impact is assessed by the total numbers of adopters and by the household and system factors influencing adoption. While the diffusion research tradition has made substantive advances in recent decades, attention to what happens to technologies after adaptive, on-farm research trials continues to be limited in practice. While a host of newer approaches designed to correct for past shortcomings in diffusion research is now available, integrative methodologies that capitalize on the strengths of these different traditions are sorely needed. This article presents a more encompassing methodology for tracking the fate of technological interventions, illustrating the potential applications of findings for enhancing the positive impact of agricultural research and extension in the region. Laura German holds a BSc in Agricultural Engineering from Cornell University (2001) and a PhD in Ecological Anthropology from the University of Georgia (2001). Following many years of involvement in Latin America, she took a position in 2002 as Scientist for the World Agroforestry Centre (ICRAF) under the African Highlands Initiative, an ecoregional program of the Consultative Group for International Agricultural Research (CGIAR) and a network of the Association for Strengthening Agricultural Research in East and Central Africa. Her current research interests include theoretical and applied work in three main areas: (1) research-development linkages; (2) integrated natural resource management at the landscape/micro-catchment scale; and (3) collective action in natural resource management. Jeremias Mowo holds a BSc in Agriculture (1979) from Dar Es Salaam University and an MSc (1983) and PhD (2000) in Soil Science from Wageningen University. He worked as soil fertility specialist in cotton-based agro-ecosystems for 11 years and coordinated soil research in Tanzania for four years. From 1998 to 2005, he worked under the African Highlands Initiative as Coordinator for the Lushoto Benchmark Site in Tanzania. In May 2005, he took up a two-year contract with the Institut des Sciences Agronomiques du Rwanda (ISAR) as Senior Scientist in Soil and Water Management Research where he is currently spearheading the Integrated Watershed Management approach. His research interests include integrated natural resource management, farmer participatory research, methods and approaches for technology transfer, soil and water management research, organic farming and use of indigenous knowledge in soil management. Margaret Kingamkono holds a BSc in Agriculture (1994) and an MSc in Agriculture (1996) from the Sokoine University of Agriculture. Since 1995, she has worked for the Ministry of Agriculture and Food Security in Tanzania with a focus on livestock production. She has carried out extensive collaborative work on areas of land resource management, participatory approaches, and crop-livestock-agroforestry interactions. Her research interests include gender and development and integrated natural resource management.  相似文献   

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The research described in this paper was designed to identify the factors that influence the importance small-scale farmers place on different marketing channels of short food supply chains. The focus concerns two entirely different types of market that are present in the bigger cities in Hungary: ‘conventional’ markets where there are no restrictions on locality but the farmer-market relationship is based on binding contracts, and newly-emergent farmers’ markets at which only local growers can sell ad hoc, using their own portable facilities. Results are based on a survey that was conducted in 2013 among 156 Hungarian market oriented farmer-vendors at different types of market and confirm that different markets are visited by different types of farmers. Farmers who favour conventional markets are typically less educated, operate on smaller scales and are more committed to their chosen markets via long-term contracts (which reduce the probability of their trying other outlets). The preference for farmers’ markets is stronger with farmers who are more open to cooperation, have specific investment plans for developing their farms and among those who are specifically looking to directly interact with their customers to avoid middlemen. The relevance of the findings is highlighted by the ongoing Short Food Supply Chain Thematic Sub-programme in the present European Union financing period; farmers’ profiles in any given marketing channel must be understood if short food supply chains are to be effectively promoted. Different types of small-scale farmers will benefit from different supporting frameworks, interventions, and initiatives.  相似文献   

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Amongst the environmental and social externalities generated by Australian agriculture are a number of risks both to the health and safety of communities living near sites of agricultural production, and to the end consumers of agricultural products. Responses to these potential risks – and to problems of environmental sustainability more generally – have included a number of programs to variously: define best-practice for particular industries; implement Quality Assurance procedures; and encourage the formation of self-help community Landcare groups. Taken together, these programs appear to deal comprehensively with both the social and environmental risks associated with agricultural production and products. However, these programs may also be interpreted as strategies that actually encourage the further intensification of agriculture, while attempting to reassure consumers that their food is safe and that farmers are doing all they can to protect the environment. Investigation of the Australian cotton and beef industries illustrates a number of strategies that have become evident between farmers, agri-science agencies, and the retail sector to manage these risks and define good farming practices in ways that satisfy their own perceived interests. Contrary to the image, therefore, of green consumption that is emerging as an integrated concern for clean (and thereby healthy) and sustainably produced foods, it appears that mainstream agricultural industries have bifurcated these concerns in ways that distract attention from production and processing methods, leaving conflict over on-farm production methods a characteristic only of those industries believed to have direct health impacts on nearby communities.  相似文献   

7.
This paper contributes to the growing social science scholarship on organic agriculture in the global South. A “boundary” framework is used to understand how negotiation among socially and geographically disparate social worlds (e.g., non-governmental organizations (NGOs), foreign donors, agricultural researchers, and small-scale farmers) has resulted in the diffusion of non-certified organic agriculture in Kenya. National and local NGOs dedicated to organic agriculture promotion, training, research, and outreach are conceptualized as “boundary organizations.” Situated at the intersection of multiple social worlds, these NGOs engage in “strategic bridge building” and “strategic boundary-work.” Strategic bridge building involves the creation and use of “boundary objects” and “hybrid forms” that serve as meeting grounds for otherwise disconnected social worlds. Strategic boundary-work involves efforts to “scientize,” and thereby legitimize, organic agriculture in the eyes of foreign donors, potential research collaborators, the Kenyan state, and farmers. Examples of strategic bridge building and boundary-work are presented in the paper. The Kenyan case illustrates that different social actors can unite around a shared objective – namely, the promotion and legitimization of organic agriculture as an alternative to the Green Revolution (GR) technological package.
Jessica R. GoldbergerEmail:
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8.
The rice–crayfish farming model has been rapidly developed and become an economically viable method to supply food in China in recent years.  However, its environmental and economic sustainability has not been thoroughly investigated.  This study uses a survey in 2016 and a field experiment in 2017 in Qianjiang, Hubei Province, China to assess the relative economics of concurrent rice–wheat (RW), rice–crayfish (RC), and crayfish monoculture (CM) models in waterlogged land areas.  The field survey indicated that the RC model had a higher benefit–cost ratio (3.5:1) than the RW (2.0:1) and CM (3.1:1) models and the RC model protected farmers’ enthusiasm for grain production facing unfavourable weather conditions.  The field experiment aimed to explore nitrogen management strategies in RC fields.  In the experiment, four levels of nitrogen concentration gradient - 0 kg N ha–1 (0 N), 75 kg N ha–1 (75 N), 150 kg N ha–1 (150 N) and 225 kg N ha–1 (225 N), were set in a 2-year-old rice–crayfish (RC2) field, an 8-year-old rice–crayfish (RC8) field, and a RW field as a control.  The field experiment results suggested that the peak  rice yield in RW, RC2, and RC8 occurred when 225 N, 150 N and 75 N were used, respectively.  In RC2 and RC8, however, residual feed-nitrogen that was not used by crayfish was utilized by rice plants.  Thus, an optimal amount of nitrogen in RC fields was proposed to improve the nitrogen use efficiency and reduce environmental pollution by nitrogen fertilizer.  Farmers use less nitrogen but have higher net income in RC than in RW and CM.  It is necessary to sustainably develop integrated farming technologies (i.e., proper field configurations for rice fields) to effectively sustain rice production.  The results also showed that the RC farming model was a viable diversification option for rice farmers in waterlogged land.    相似文献   

9.
This study investigates the impact of the New Rural Cooperative Medical Scheme(NRCMS) on rural households to escape poverty. We employ the instrumental variable method, the IVProbit model, to analyze the national data from the rural-resident field survey by the China Family Panel Studies(CFPS) in 2016. Based on the large-scale data, we found that, first, the hospitalization of family members is the key factor in increasing the risk of the family falling into poverty. The NRCMS has significantly reduced the likely risk of falling into poverty. Second, the impact of the NRCMS on poverty alleviation varies among groups with different levels of income. There is no impact on the upper-middle and high-income groups; in contrast, the NRCMS has substantially improved the capacity of low-income rural families to prevent poverty due to illness, especially for the lower-middle-income group. Third, there exist significant regional differences in the impact of NRCMS on the health poverty alleviation of rural households in China. The NRCMS has successfully reduced the risk of rural households in the western region falling into poverty, simultaneously, no significant impact on those in the eastern and central regions. In order to diminish and eliminate poverty eventually and boost rural residents' capacity for income acquisition, we propose the following: raise the actual compensation ratio of the NRCMS, control the rising expense of NRCMS by promoting the payment method reform, construct the comprehensive healthcare system in the western region, strengthen the medical security for the poor in remote area, and enhance the living environment for rural residents.  相似文献   

10.
This paper seeks to clarify and strengthen the ways that cultural economy is used as an analytical tool and methodological approach to studying agro-food systems. The theoretical concept of cultural economy has received much attention in economic and cultural geography over the past decade. However, use of the term remains arguably vague and ambiguous. This paper argues that cultural economy is most constructive when regarded as a new epistemological approach to society and the economy. A focus on the ways that food is known as “quality” represents the material and symbolic practices that contribute to a new way of thinking about the economy. This point is illustrated in a case study of japonica rice grown in northeast China. A unique combination of social, economic, political, historical, and geographical factors come together in this region to produce rice that is generally identified within China today as “quality” rice. Situating northeast japonica rice in a greater context of a “politics of quality” in Chinese society, this case emphasizes the value of cultural economy to understand agro-food systems.  相似文献   

11.
Genetically modified (GM) cassava is currently being developed to address problems of diseases that threaten the food security of farmers in developing countries. The technologies are aimed at smallholder farmers, in hopes of reducing the vulnerability of cassava production to these diseases. In this paper we examine barriers to farmers’ voice in the development of GM cassava. We also examine the role of a translational research process to enhance farmers’ voice, to understand the sources of vulnerability farmers in a group in Kenya’s Coast face, and to determine if their concerns are consistent with those of the scientists in agriculture addressing farmers’ needs. A two-way communication participatory process provided insights into the complex vulnerability context of farmers, their primary concerns with processing and markets of cassava in order to improve livelihoods, the lack of networks with two way communication flows, and the lack of information on GM technologies. The translational research engaged farmers and scientists in an iterative process where scientists are learning what farmers need, and farmers are learning about the potential benefits and risks from GM technologies, while at the same time expressing their concerns.  相似文献   

12.
Agriculture plays a key role in national economies and individual livelihoods in many developing countries, and yet agriculture as a field of study and an occupation remain under-emphasized in many educational systems. In addition, working in agriculture is often perceived as being less desirable than other fields, and not a viable or compelling option for students who have received a post-secondary education. This article explores the historical and contemporary perceptions of agriculture as a field of study and an occupation globally, and applies themes from the literature to analyze primary data from focus groups with international students studying for university degrees in the United States. The article analyzes students’ perceptions and experiences in four countries—Bangladesh, Nepal, Honduras and Haiti—in order to make recommendations about how best to address challenges and develop capacity in agricultural education and employment in low-income countries.  相似文献   

13.
Using the case of food safety governance reform in Japan between 2001 and 2003, this paper examines the relationship between science and trust. The paper explains how the discovery of the first BSE positive cow and consequent food safety scandals in 2001 politicized the role of science in protecting the safety of the food supply. The analysis of the Parliamentary debate focuses on the contestation among legislators and other participants over three dimensions of risk science, including “knowledge,” “objects,” and “beneficiaries.” The metaphor of “seven samurai” and the relationally situated roles of “samurai,” “bandits,” and “beneficiaries” are used to show that in the process of policy making certain moral and ethical expectations on a new expert institution for food safety were contested and negotiated to frame responsibilities and commitments of social actors for creating the food system based on trust.
Keiko TanakaEmail:
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14.
Since the beginning of the new millennium, initiatives known as roundtables have been developed to create voluntary sustainability standards for agricultural commodities. Intended to be private and voluntary in nature, these initiatives claim their legitimacy from their ability to ensure the participation of all categories of stakeholders in horizontal participatory and inclusive processes. This article characterizes the political and material instruments employed as the means of formulating agreement and taking a variety of voices into consideration in these arenas. Referring to the specific case of the “Roundtable on Sustainable Palm Oil”, I undertake a detailed analysis of the tensions relating to different forms of participation, which create a gap between “local minority voices” and international stakeholders—either non-governmental organizations (NGOs) or industries. Local communities and small-scale farmers face difficulties when making their voices heard in the form of debate proposed. Firstly, some participants attempt to re-impose a vertical hierarchical relationship between small-scale farmers or affected communities and company managers/directors in order to deprive the former of their powers of representation and of being able to transform reality. Secondly, the liberalism of interest groups in the roundtable accords value to experts, global knowledge, strategy, and detachment, at the expense of other capabilities of rooted or attached people who come to defend their real lives with a desire to raise critical issues of injustice. In this context, I highlight the capacity of local NGOs to relieve some of those tensions and to help locally affected communities and small-scale farmers introduce public stages for debates, by accommodating other forms of participation apart from the liberal one. By being close to and by restoring their dignity through a specific work of solicitude and care, local NGOs prepare affected people for public speaking.  相似文献   

15.
Data on farming systems in Petén, Guatemala, were used to develop an agricultural intensity index. The index can be used to assign an intensity “score” to a given farming system based on the array of practices used by the farmer, each practice’s contribution to production intensity, and the scale at which these practices are used. The scores assigned to 118 farmers in three study areas in Petén were analyzed through analysis of variance (ANOVA) to identify the factors that account for the variation in intensity levels, as measured through the index. The analyses reveal that the factors influencing agricultural intensity in Petén vary greatly from one study area to the next. This is due to differences in livelihood opportunities and strategies that, in turn, affect how agriculture fits into the local economy and how and why intensification is pursued. Variation in intensity levels can best be understood by considering the factors at the household and sub-regional scales that influence (a) whether farmers feel a need to intensify, (b) whether they see some benefit in doing so, and (c) whether they have the resources required to intensify production through particular strategies. Close attention must be paid to these factors by conservation and development organizations seeking to influence land use patterns and conserve forest in Petén. Avrum J. Shriar is an Assistant Professor at Virginia Commonwealth University where he specializes in Environmental Geography, Rural Development and Land Use, Farming Systems, and Latin America and the Caribbean. He holds a BA in Geography from Bishop’s University in Lennoxville, Quebec, a Master of Environmental Studies (MES) from Dalhousie University in Halifax, Nova Scotia; and a PhD in Geography from the University of Florida in Gainesville. Some of his recent articles have appeared in Food Policy, Geoforum, Human Ecology, Agroforestry Systems, and the Delaware Review of Latin American Studies.  相似文献   

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The analysis distinguishes two types of standards for defining organic produce; process standards and product standards. Process standards define organic products by the method and means of production. Product standards define organic by the physical quality of the end product. The National Organic Program (NOP) uses process standards as the basis for defining organic. However, the situation is complicated by agricultural production practices, which sometimes result in the migration of NOP prohibited substances from conventional to organic fields. When this interaction alters the value of the product or the costs of production, a production externality is said to exist. Defining organic using process, rather than product standards, influences the burden and character of production externalities. The NOPs emphasis on process standards reduces the likelihood that production externalities will emerge.B. James Deaton is an Assistant Professor in the Department of Business and Agricultural Economics, University of Guelph, Canada. His research examines environmental and natural resource issues. He is particularly interested in the manner in which laws, rules, and standards influence environmental quality, natural resource use, and economic development. Additional research examines the relationship between different forms of private property and economic development, public support for various criteria used to preserve farmland, and the social construction of production externalities in agriculture. Prior to his PhD training, he worked on economic development projects in Lesotho (Southern Africa) and the Appalachian region of eastern Kentucky.John P. Hoehn is a Professor of Environmental and Natural Resource Economics in the Department of Agricultural Economics, Michigan State University. His teaching and research activities address environmental and natural resource policies, benefit-cost analysis of environmental improvements, methods for valuing non-market goods, improved institutions for protecting, managing, and using environmental resources, and the economics of ecological resources. He teaches core courses in the departmental and university-wide graduate programs in environmental and resource economics.  相似文献   

18.
As concerns heighten over links between biomass production and land grabs in the global south, attention is turning to understanding the role of governance of biofuels systems, whereby decision-making and conduct are not solely determined through government regulations but increasingly shaped by non-state actors, including multi-stakeholder initiatives (MSI). Launched in 2005, Bonsucro is the principal MSI that focuses on sustainability standards for sugar and sugarcane ethanol production. Bonsucro claims that because it is free from government interference and draws on scientific metrics, their standards transcend localized, political–economic contexts. In this paper, we illustrate how the local context shapes the prospects for Bonsucro sustainably certified biofuel production in relation to land and water grabs. To accomplish this, our case focuses on Colombia, which has used a range of national policy mandates to establish itself as one of the larger producers of agrofuels in Latin America. We draw on interviews with stakeholders in the sugar and ethanol industries, paired with an examination of Bonsucro principles on land rights and water use, to illustrate how the sugar industry is framing their participation in Bonsucro, and the effects of the increasing intensification of sugarcane for ethanol production on land and water access for communities. We find that within the context of Colombia, efforts such as Bonsucro provide a veil of legitimacy and authority to a system that is premised on deeply entrenched historical patterns of inequitable land ownership patterns and access to natural resources.  相似文献   

19.
武夷山茶文化资源产业化经营是实现武夷山茶文化资源创意、高效、融合发展的关键途径,“一带一路”战略的提出为其深化发展提供了契机。武夷山茶文化资源产业化虽与“一带一路”战略有契合点,但仍存在茶文化资源开发意识缺乏、视野局限、深度不够以及人才匮乏的问题,须以国际视野提升产品质量,培养创意人才等方式进一步推进武夷山茶文化资源产业化。  相似文献   

20.
Experts identified water quality, manure, good handling practices (including personal hygiene and equipment sanitation), and traceability as critical farm problem areas that, if addressed, are likely to decrease risk associated with microbial contamination of fresh produce from all scales of agriculture. However, the diverse nature of production strategies used by produce farmers presents multiple options for addressing foodborne illness issues while simultaneously creating potential complications. We use a mental models methodology to enhance our understanding of the underlying factors and assumptions of small, medium, and large produce growers that influence their decision-making processes for contamination prevention and control. This empirical evidence demonstrates how challenges and opportunities to food safety are related to the scale of production and marketing strategies. We believe that refining the development of standards and existing extension and outreach food safety programs are important to both consumer protection and supporting agricultural communities. Additionally, this approach will help develop and refine food safety programs that will result in empirically grounded recommendations based on identified grower information needs.  相似文献   

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