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1.
Farmers’ assessments of private adaptive measures to climate change and influential factors: a study in the Mekong Delta,Vietnam 总被引：2，自引：0，他引：2
Adaptation to climate change in agricultural settings depends on understanding farmers’ perceptions of the nature of climate change, their agency in adapting and the efficacy of adaptive measures themselves. Such knowledge can improve mitigation and adaptation strategies. This study addresses the limited understanding of how farmers appraise their private adaptive measures and influential factors. It uses data from structured interviews with 598 rice farmers in the Mekong Delta, Vietnam. Based on protection motivation theory, farmers’ assessments of private adaptive measures were measured by perceived self-efficacy, perceived adaptation efficacy and perceived adaptation cost. Multiple regressions were used to understand significant factors affecting those assessments. Some demographic and socio-economic factors, belief in climate change, information and objective resources were found to influence farmers’ adaptation assessments. It is shown that the sources and quality of information are particularly important. The improvement of both the accessibility and usefulness of local services (e.g. irrigation, agricultural extension, credit and health care) is deemed a necessity for successful adaptation strategies in the Mekong Delta. The paper also shows the application of PMT in measuring farmers’ appraisals of private adaptive measures to climate change, thereby opening this area for further research. 相似文献
2.
Nitrogen supply is critical in attaining yield potential. Achieving the 50% higher yields that will be needed by 2025 will require at least double the 10 m tons of N fertilizer that is currently used each year for rice production. But manufacturing of fertilizer N is dependent on fast depleting non-renewable energy resources. It is in this context that biological nitrogen-fixation-derived N assumes importance in the lowland soils that provide about 86% of the world's rice.Among the conventional systems, green-manure legumes have high N supply potential. But due to associated additional costs such as labour and land opportunity, they do not form an attractive option for farmers. Rice associative N2 fixation (ANF) although has low activities, any increase will be attractive to farmers as it does not require changes in existing cropping systems, and soil and water management practices. Recently, we identified quantitative trait loci underlying ANF in rice (Wu, P.; Zhang, G.; Ladha, J. K.; McCouch, S. and Huang, N.: Restriction fragment length polymorphic markers associated with rice varietal ability to stimulate nitrogen fixation in rhizosphere. Rice Genetic Newsletter 1994 — submitted). The presence of this trait in rice provides an evidence of the occurrence of genetic factors which regulate interaction of rice with diazotrophs in rhizosphere. However, the ANF trait governing the loose diazotroph-rice association appears to have limited potential for enhancing yield. To achieve higher yields, intimate association similar to sugar cane-Acetobacter/legume-rhizobia symbioses will have to be developed in rice. In this paper, we discuss the strategies for transferring nitrogen-fixing capacity to rice. 相似文献
3.
South Australian farmers’ markets: tools for enhancing the multifunctionality of Australian agriculture 总被引：1，自引：0，他引：1
This paper critically examines the role of farmers’ markets in Australian agriculture. A case study is undertaken in South Australia, where all stallholders at three farmers’ markets situated in Adelaide, Willunga and Berri were surveyed regarding their production and marketing techniques. Overall responses supported literature highlighting the importance of farmers’ markets to the producers who chose to exploit this marketing niche. A strong co-reliance on ‘wholesale sales’ was also recognised, suggesting an important integration of productivist and post-productivist approaches to agricultural development. Of most promise for long-term agricultural sustainability was evidence that certain groups of farmers were found to be realising the potential of these and other alternative markets, in terms of their risk reducing capacity, and diversifying to include various conservation values into their agricultural enterprises. These groups were less concerned about market fluctuations and more concerned with issues of social equity, environmental health and having fun, which meant they unwittingly epitomised the goals of political ecology, by challenging the dominant agricultural methods of production and marketing. It seems these groups also recognised that the direct nature of their transactions would sow beneficial social, environmental and economic ‘seeds’ for change. Finally, it is argued that policies to improve access to farmers’ markets and reduce the cost of participation would assist small scale Australian agricultural producers to evolve smoothly into a multifunctional era. 相似文献
4.
Cleophas Lado 《GeoJournal》1998,45(3):165-176
In many developing countries, research institutions or centres have been established to develop and/or adapt technologies that would help agricultural development. This is particularly true in Africa where national efforts have been supplemented with international research institutes. Although some modest progress has been achieved in improving agricultural technology, on the whole, the improvement record is not quite encouraging among the small-scale farmers. In many areas, either there are no improved technologies, or where they exist, are unacceptable by farmers. However, where useful technologies exist, their spread has been very limited and where they have been adapted, the benefits only accrue to a small segment of the community. The logical question posed is: why and how do we find ourselves in the current situation? This paper considers the view that to understand fully why the available technologies have remained largely at the research centres, there is need to examine the whole process of research, development, dissemination and utilization of agricultural technology. It is significant to investigate the structural constraints and prospects under which those involved in the process work, their motivations and the interactions between different groups. The traditional ‘top-down’ of development strategy should be supplemented with farmers' indigenous knowledge, and programmes encouraging transfer of agricultural technology should include institutional support. Only by the identification of farmers' environmental and resource utilisation, preferences, socio-economic circumstances and constraints can a development programme of optimum meaning to farmers be devised and implemented with success. 相似文献
5.
While a bottom-up approach to identifying problems affecting food production among small-scale farmers has been urged as an appropriate means of finding sustainable solutions, few studies have determined the practical process of doing so and measured the outcomes of such an approach. This paper uses information gained mainly through focus groups with small-scale farmers and semi-structured interviews, to identify farmers’ perceptions of reasons behind low yields and low agricultural production in three communities of Cameroon’s North West region. Three biophysical factors are identified as the main reasons of low production: the long and more frequent dry spells and late start of the start of the rainy season. Three socio-economic reasons are identified as most important: land scarcity, money to invest in agriculture and labour scarcity. Farmers rank their reasons based on the importance to their agricultural production in their local area. Some of the important claims made by farmers are tested using field data and statistical analysis. These include the claims that: (1) the rainy season is increasingly starting later than it used to; and (2) the length of dry spells are increasingly longer than they used to be. The results of these statistical tests are significant, showing that farmers’ knowledge of some of the local problems affecting their activities can serve as an important input into formal research and policy design. Peoples’ understanding of a problem affects the way they will act on it—in terms of searching for solutions and implementing change. Farmers can therefore provide useful insights on why they think there are large yield gaps within their local production environments. The current agricultural development policy of the Cameroon government is advocating greater public–private engagement and can benefit from farmers’ inputs and opinions in the design of relevant policies. In the same light, nonlocal based researchers and research institutions can draw on farmers’ knowledge to create and accumulate knowledge on sustainable solutions to problems of low yields and low food production in Cameroon. 相似文献
6.
Management and environmental constraints to rice yield in a paddy tract (lowland rice field) was studied within a village irrigation system in Sri Lanka. The relative importance of water coverage during the critical period and soil fertility variables on the yield variations were analysed. For the upper part of the paddy tract having adequate water supply, environmental and management factors seemed to explain the large variations in yield. For the middle and lower parts, with a shortage of water, water coverage was the only significant explanatory factor.For efficient use of a scarce water supply farmers allocated water first to the upper part, which resulted in water deficiency further down. An alternative strategy for water allocation, where the lower more fertile part of the paddy tract is favoured, would not avoid the risk of water scarcity for the individual farmer but there would be a potential for increase in the total production. 相似文献
7.
The impact of severe natural disasters on the livelihoods of farmers in mountainous areas: a case study of Qingping Township,Mianzhu City 总被引：2，自引：0，他引：2
The ‘5.12’ earthquake in 2008 and the ‘8.13’ debris flow in 2010 brought huge losses of life and property to Qingping Township. Farmers’ livelihoods assets were also seriously affected and damaged. These led to a change in farmers’ livelihood styles and reduction in their income. A study of the impact of natural disasters on farmers’ livelihoods in mountainous areas would have significant importance for policy making. Based on field survey data from sample households, this study comparatively analyzed the assets, livelihood styles and income of farmers over three periods—2007, 2009 after the ‘5.12’ earthquake, and 2 months after ‘8.13’ debris flows. It presents the following findings: (1) livelihood assets suffered heavy losses; (2) livelihood styles were significantly changed; and (3) the sustainability of farmer income was adversely influenced. These results suggest that, during the process of post-disaster reconstruction work, affected farmers’ security, the carrying capacity of livelihood assets, and the enhancement of employment and livelihood choice are worthy of much attention from policy makers. 相似文献
8.
Breaking the yield frontier of rice 总被引：26，自引：0，他引：26
Gurdev S. Khush 《GeoJournal》1995,35(3):329-332
Major increases in rice production have occurred during the last 25 years, due to large-scale adoption of high-yielding semidwarf rice varieties. However, the rate of increase of rice production has slowed down, and the rate of population growth of rice consumers is now higher than the rate of increase of rice production. Severe food shortages are therefore likely to occur in 20–30 years if the trend is not reversed. To meet these food needs, rice varieties with higher yield potential are needed. The yield potential of the modern high-yielding varieties grown under the best tropical conditions is 10 t ha–1. A research program is under way to develop varieties with a yield potential of 15 t ha–1. One strategy aims to develop new rice plants with a harvest index of 0.6 (60% grain: 40% straw by weight) and with an increased ability for photosynthesis to increase total biological yield. The harvest index of the modern high-yielding varieties is 0.5. Such new varieties should have a yield potential of 12.5–13 tons ha–1. These new plant type varieties will be used to produce hybrid rices with a yield advantage of 25% over the best parent. Such hybrids would have a yield potential of 15 t ha–1. 相似文献
9.
Intensification of irrigated rice systems: Learning from the past to meet future challenges 总被引：6，自引：0，他引：6
More than 75% of all rice is produced on irrigated land. Although the green revolution was driven by both an expansion of irrigated rice area and increased yield per unit land area, the next quantum leap must come exclusively from increasing yields on existing crop land. We review the structural changes that have accompanied the intensification process, and examine the major biophysical and economic challenges that confront Asian farmers who must further intensify irrigated rice systems to achieve a yield increase of more than 60% by the year 2025. 相似文献
10.
Assessment of rice yield loss due to torrential rain: a case study of Yuhang County, Zhejiang Province, China 总被引：2，自引：0，他引：2
This study adopts a loss assessment and indemnity approach for rice crops at risk of flooding in Yuhang County, Zhejiang Province.
Employing a hydrological model for simulating floods and a reduction model for predicting rice yield, the relationship between
the rate of reduction in the rice yield and precipitation is discussed. We argue that the yield reduction rate can be assessed
according to the amount of precipitation and designed a weather-based indemnity index for agricultural insurance purposes
in Zhejiang Province. With geographic information system technology, the yield reduction rate and weather-based indemnity
index were refined and found to effectively reduce the shortcomings of traditional agricultural insurance, i.e., moral hazard,
large error in assessing disaster loss and high basis risk. The validity of the method was verified by the amount of rice
lost due to No. 16 typhoon Krosa in 2007, and the results show that the proposed method can well simulate the reduction rate
of rice yield according to precipitation data. 相似文献
11.
《Geoforum》2013
Farmers are not commonly included in studies of transnational actors, but with the globalization of agricultural markets, and the neoliberal reform of national agricultural sectors, an increasing number of family farm-entrepreneurs have become engaged in transnational activities. Drawing on interviews with ‘globally-engaged’ farmers in Australia – a country in which expansion into transnational activities has been encouraged by the radical deregulation of domestic markets – this paper explores the transnational mobilities of farmers who have sought to capitalize on the advantages of globalization by directly trading with international partners, establishing international business contacts, and learning international best practice in farm efficiency and environmental performance. In particular, the paper examines the varying spatialities and forms of mobility executed by farmers and observes how different patterns of mobility are executed in response to the particular exigencies of their respective industries as well as the ongoing imperatives of maintaining a farm business. By analyzing the farmers’ own narratives of these different spatialities, the paper develops a more critical and reflexive perspective on globalization and its impact on rural producers, with travel becoming both an opportunity to be enjoyed and a compulsion to be endured by those forced to operate in a climate where state-based support structures are absent. 相似文献
12.
水资源是支撑粮食生产的重要因素之一,气候变化驱动下的水资源变化及对粮食产量的影响是当前研究的国际前沿和热点问题。以汾河流域冬小麦和夏玉米2种主要粮食作物为研究对象,利用线性回归、人工神经网络、支持向量机、随机森林、径向基网络、极限学习机等6种机器学习算法构建粮食产量模拟模型,基于气候弹性系数法分析水资源量对气候变化响应关系,在流域尺度上研究粮食产量对气候变化驱动水资源变化的综合响应。结果表明:①机器学习算法能够较好地模拟汾河流域的冬小麦和夏玉米产量;②降水增加10%导致汾河流域水资源量增加19.4%,气温升高1℃导致水资源量减少4.3%;③当降水减少10%~30%时,冬小麦产量减少6.4%~19.3%,夏玉米产量减少4.0%~15.0%;④当气温升高0.5~3.0℃时,冬小麦产量预计增加1.8%~17.1%,夏玉米产量预计增加1.2%~7.9%;⑤汾河流域冬小麦产量对降水和气温变化的敏感性大于夏玉米。相关成果对于区域水资源管理和农业生产策略制定具有重要的科学意义和实用价值。 相似文献
13.
Scherrer Cyrille Schweitzer Ryan Bünzli Marc-André Milnes Ellen 《Hydrogeology Journal》2021,29(6):2033-2051
Emergency responses in humanitarian contexts require rapid set-up of water supply. Boreholes are often drilled where the needs are highest and not where hydrogeological conditions are most favourable. The Rapid Groundwater Potential Mapping (RGWPM) methodology was therefore developed as a practical tool to support borehole siting when time is critical, allowing strategic planning of geophysical campaigns. RGWPM is based on the combined analysis of satellite images, digital elevation models and geological maps, obtained through spatial overlay of the two main hydrogeological variables controlling groundwater potential: water availability (WA) and reservoir capacity (RC). The WA associates hydrogeomorphological features to groundwater dynamic processes, while the RC reflects estimates of the hydraulic conductivity. RGWPM maps are produced through an overlay of WA and RC with the overall groundwater potential (GWP) characterized as ‘very low’, ‘low’, ‘medium’, and ‘high’, with each zone associated to a specific water supply option. The first RGWPM map was elaborated during a drilling campaign in Northern Uganda. The average yield for the eight boreholes sited ‘with’ RGWPM was 35 m3/h versus 3 m3/h for the 92 preexisting boreholes that were sited ‘without’ RGWPM. Statistical comparison of the classified yields of all hundred boreholes with the RGWPM predicted-yield ranges revealed a good correlation for the ‘low’ GWP unit, highlighting areas where well siting for motorised systems should be avoided. A rather poor correlation of 33% was found for the ‘medium’ GWP unit, believed to be artificially induced by the numerous hand pumps (low yields) located in potentially higher yielding areas.
相似文献14.
《Geoforum》2015
This paper explores how the implementation of the EU’s Common Agricultural Policy (CAP) and agri-environment measures in particular have been used to increase state oversight into rural affairs and land use in Hungary. The governmentalities of the agricultural sector through Europeanisation include stringent inspections and controls as part and parcel of accountability drives around the disbursement of subsidies. Agricultural surveillance mechanisms and processes are recounted here as holistic, perpetual and immediate, composed of the remote, administrative, as well as embodied physical encounters. Through ethnographic engagement with the Hungarian state’s interactions with its farmers during inspections, the forms and consequences of neoliberal governmentality are given life in a post-socialist context. I elucidate the numerous subjectivities involved in these encounters, and how bureaucratic and administrative requirements underlie the rise of private consultants, where social capital and informal networks are of great importance for the successful navigation of the agricultural system. On the part of farmers, subsidies’ accountability systems were lived as unjust, giving rise to speculation around the ‘real’ intended purposes of agri-environment legislation, which in turn undermines the expert authority of the state and heightens skepticism towards the European ‘project’. 相似文献
15.
《Geoforum》2013
While plant diseases have been the subject of scientific research, little is known about the perceptions of key actors towards plant disease risk within specific food sectors. Drawing on concepts of risk and uncertainty, and using in-depth interviews, this paper examines the ways in which endemic plant disease risks in the UK wheat sector are perceived and managed by key ‘upstream’ and ‘downstream’ businesses, as well as by farmers and agronomists. A majority of interviewees feel that plant disease is a controllable risk and one that rests mainly at the point of production (i.e. with farmers) within the wheat sector. This assumed ‘control’ is based mainly around the availability of plant protection products (e.g. fungicides) which reduce the sense of risk attributable to outbreaks of plant disease. As a consequence, there can be a tendency to grow higher-yielding wheat varieties that are less disease-resistant. The potential banning of certain fungicides under EU legislation and climate change are perceived future threats that could increase uncertainty and change the balance between ‘control’ and ‘resistance’, the latter through the use of more disease-resistant wheat varieties. Further research is needed on the perceived impacts of plant diseases and on how different wheat sector actors will contribute to the future control of plant diseases and the development of more integrated systems of plant disease management. 相似文献
16.
17.
The fifth assessment report (AR5) predicted that land temperatures would rise faster over Africa than other global averages while changes in rainfall are uncertain across Sub-Saharan Africa. These portend water availability challenges with direct impacts on agricultural production. Existing studies on yield vulnerability in Nigeria are mostly at a national scale, which is not adequate for local decision making. This study provides a spatially explicit model of Maize yield vulnerabilities across the growing areas (GA). Thereby, turning available data into actionable information to support development actions. Yield vulnerability index was constructed as a relationship among exposure, yield sensitivity and adaptive capacity. Exposure was computed as the ratio between long and short-term climatic factors. Yield sensitivities were expressed as the ratio between expected and actual yield. Adaptive capacity was captured using a combination of socio-economic proxies. The result shows that Maize yields were vulnerable to climate variability across most of the GAs. Exposure values indicate a very high level of climate variability with the northern region more exposed. Yield sensitivity ranges between ranges 0.47 and 0.95, and highest along the northern extremes, moderate sensitivities were observed across large tracts of the north-west, northeast, south-east and south–south geopolitical regions. Adaptive capacity is highly variable ranging between 0.27 and 1. Yield vulnerability ranges between 0.46 and 1.51. The general assumption of a north–south divide for yield vulnerability was invalidated. Vulnerability is more disparate beyond latitudinal differences. The model presented, creates a framework to support targeted response, and opportunity for building resilience to climate change impact for crop yield.
相似文献18.
《Geoforum》2013
This paper considers the meaning of local, quality food in the context of a farmer’s market in Montpellier, France. The focus is on understanding how farmers conceptualize ‘local’, how they perceive and cater to their clients’ demand for quality food, and what mechanisms are deployed to ensure a joint approach to these conventions. With a market association capable of carrying out site inspections to weed out ‘fake-farmers’ and an expectation that each vendor would participate in staged demonstrations of agrarian competency, the market emerges as an exclusive and tightly regulated commercial space that promotes both local protectionism and alternative consumption practices. 相似文献
19.
River Basin Development is one of the key agricultural programmes embarked upon by Nigeria to meet the challenges of escalating import bills on food. This paper takes a critical look at the various efforts made by the management of the River Basin Authorities in responding to the current food crisis. The rationale for the huge financial allocation made to the Authorities is questioned, and the management lapses in their key areas of operation, such as irrigation, mechanization and extension services, are discussed. It is found that despite the huge financial investments made in the river basins, their impact is hardly felt, not only in terms of food production capacity but also in the production performance of the peasant farmers. The paper argues that the problem of food crisis in Nigeria could be solved by strengthening the ability of the peasant farmers and farmers co-operatives through financial aid and extension services, and not by huge financial investments on high technology agricultural projects, characterized by centralized administration and expatriáte management. 相似文献
20.
河北省太行山山前平原浅层地下水位持续下降,问题十分突出,然而,该区域又是我国优质冬小麦的重要产区。能否实现在浅层地下水采补平衡的同时做到冬小麦稳产,是该区域水资源保护和农业生产管理工作中亟待回答的重要问题。基于分布式水文模型的模拟结果表明:在该区域若要实现地下水位止降回升这一压采目标,仅利用浅层地下水进行灌溉,冬小麦的产量会减少40%以上。考虑到南水北调中线工程的引水线路自南向北贯穿河北省太行山山前平原,建议在冬小麦关键需水期的灌溉中采用“一水用浅层地下水另一水用南水北调水”的“修改的春浇两水”模式。基于模拟结果的估算表明:在这种限水灌溉模式下有望实现浅层地下水采补基本平衡且冬小麦基本稳产。值得注意的是,这种“修改的春浇两水”模式,需要南水北调中线引水工程每年提供的灌溉水量大约为8.6×108 m3,灌溉成本较纯井灌至少增加562.5～1282.5元/hm2。本研究可为我国最典型的浅层地下水超采区——河北省太行山山前平原探索保产量与节水并举的新路径提供定量化的参考。 相似文献