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Increasing agricultural production to meet the growing demand for food whilst reducing agricultural greenhouse gas (GHG) emissions is the major challenge under the changing climate. To develop long-term policies that address these challenges, strategies are needed to identify high-yield low-emission pathways for particular agricultural production systems. In this paper, we used bio-physical and socio-economic models to analyze the impact of different management practices on crop yield and emissions in two contrasting agricultural production systems of the Indo-Gangetic Plain (IGP) of India. The result revealed the importance of considering both management and socio-economic factors in the development of high-yield low-emission pathways for cereal production systems. Nitrogen use rate and frequency of application, tillage and residue management and manure application significantly affected GHG emissions from the cereal systems. In addition, various socio-economic factors such as gender, level of education, training on climate change adaptation and mitigation and access to information significantly influenced the adoption of technologies contributing to high-yield low-emission pathways. We discussed the policy implications of these findings in the context of food security and climate change.  相似文献   

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Most research linking global environmental change and food security focuses solely on agriculture: either the impact of climate change on agricultural production, or the impact of agriculture on the environment, e.g. on land use, greenhouse gas emissions, pollution and/or biodiversity. Important though food production is, many other factors also need to be considered to understand food security. A recent international conference on “Environmental Change and Food Security: Bridging Science, Policy and Development for Adaptation” included a range of papers that embraced the multiple dimensions of the food systems that underpin food security. The major conclusion from the conference was that technical fixes alone will not solve the food security challenge. Adapting to the additional threats to food security arising from major environmental changes requires an integrated food system approach, not just a focus on agricultural practices. Six key issues emerged for future research: (i) adapting food systems to global environmental change requires more than just technological solutions to increase agricultural yields; (ii) tradeoffs across multiple scales among food system outcomes are a pervasive feature of globalized food systems; (iii) within food systems, there are some key underexplored areas that are both sensitive to environmental change but also crucial to understanding its implications for food security and adaptation strategies; (iv) scenarios specifically designed to investigate the wider issues that underpin food security and the environmental consequences of different adaptation options are lacking; (v) price variability and volatility often threaten food security; and (vi) more attention needs to be paid to the governance of food systems.  相似文献   

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湖北省农地资源价值研究   总被引:22,自引:0,他引:22  
农地价值包括农地提供粮食、纤维等农副产品可计量的市场价值和提供开敞空间、维护生物多样性、保育环境、文化教育等公共物品所具有的非市场价值。科学、合理地评估农地价值,形成完整的资源成本核算体系,可缓解我国农地流失形势,为制定和实施农地生态管护政策等提供理论与实践依据。文章运用收益还原法及条件价值评估法对湖北省不同类型农地的市场价值和非市场价值进行评估,较为科学地评估出农地的整体价值,摸清农地资源的价值构成。研究表明,湖北省包括耕地、园地、林地及水域用地在内的农地资源的非市场价值现值达2514.88×108元,相当于全省2004年生产总值的39.86%,是农地价值构成中无法忽略的重要部分。全省现有耕地资源总价值达11398.77×108元,目前无法进入交易市场或有效地通过交易机制实现的非市场价值有942.63×108元,占耕地总价值的8.27%;园地及水域用地的总价值分别为3715.27×108元和10192.81×108元,非市场价值的比例份额分别达13.64%和5.48%;现有林地资源的非市场价值达506.35×108元,折合林地非市场价值约6407元/hm2。  相似文献   

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Meeting the growing demand for food in the future will require adaptation of water and land management to future conditions. We studied the extent of different adaptation options to future global change in the Mediterranean region, under scenarios of water use and availability. We focused on the most significant adaptation options for semiarid regions: implementing irrigation, changes to cropland intensity, and diversification of cropland activities. We used Conversion of Land Use on Mondial Scale (CLUMondo), a global land system model, to simulate future change to land use and land cover, and land management. To take into account future global change, we followed global outlooks for future population and climate change, and crop and livestock demand. The results indicate that the level of irrigation efficiency improvement is an important determinant of potential changes in the intensity of rain-fed land systems. No or low irrigation efficiency improvements lead to a reduction in irrigated areas, accompanied with intensification and expansion of rain-fed cropping systems. When reducing water withdrawal, total crop production in intensive rain-fed systems would need to increase significantly: by 130% without improving the irrigation efficiency in irrigated systems and by 53% under conditions of the highest possible efficiency improvement. In all scenarios, traditional Mediterranean multifunctional land systems continue to play a significant role in food production, especially in hosting livestock. Our results indicate that significant improvements to irrigation efficiency with simultaneous increase in cropland productivity are needed to satisfy future demands for food in the region. The approach can be transferred to other similar regions with strong resource limitations in terms of land and water.  相似文献   

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As climate changes due to rising concentrations of greenhouse gases in the atmosphere, agriculture will be one of the key human activities affected. Projections show that while overall global food production in the coming decades may keep pace with the food requirements of a growing world population, climate change might worsen existing regional disparities because it will reduce crop yields mostly in lands located at lower latitudes where many developing countries are situated. Strategies to enhance local adaptation capacity are therefore needed to minimize climatic impacts and to maintain regional stability of food production. At the same time, agriculture as a sector offers several opportunities to mitigate the portion of global greenhouse gas emissions that are directly dependent upon land use, land-use change, and land-management techniques. This paper reviews issues of agriculture and climate change, with special attention to adaptation and mitigation. Specifically, as adaptation and mitigation strategies in agriculture are implemented to alleviate the potential negative effects of climate change, key synergies need to be identified, as mitigation practices may compete with modifications to local agricultural practices aimed at maintaining production and income. Under future climate and socio-economic pressures, land managers and farmers will be faced with challenges in regard to selecting those mitigation and adaptation strategies that together meet food, fiber and climate policy requirements.  相似文献   

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Climate change mitigation, in the context of growing population and ever increasing economic activity, will require a transformation of energy and agricultural systems, posing significant challenges to global water resources. We use an integrated modelling framework of the water-energy-land-climate systems to assess how changes in electricity and land use, induced by climate change mitigation, impact on water demand under alternative socioeconomic (Shared Socioeconomic Pathways) and water policy assumptions (irrigation of bioenergy crops, cooling technologies for electricity generation). The impacts of climate change mitigation on cumulated global water demand across the century are highly uncertain, and depending on socioeconomic and water policy conditions, they range from a reduction of 15,000 km3 to an increase of more than 160,000 km3. The impact of irrigation of bioenergy crops is the most prominent factor, leading to significantly higher water requirements under climate change mitigation if bioenergy crops are irrigated. Differences in socioeconomic drivers and fossil fuel availability result in significant differences in electricity and bioenergy demands, in the associated electricity and primary energy mixes, and consequently in water demand. Economic affluence and abundance of fossil fuels aggravate pressures on water resources due to higher energy demand and greater deployment of water intensive technologies such as bioenergy and nuclear power. The evolution of future cooling systems is also identified as an important determinant of electricity water demand. Climate policy can result in a reduction of water demand if combined with policies on irrigation of bioenergy, and the deployment of non-water-intensive electricity sources and cooling types.  相似文献   

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A recent assessment of agricultural greenhouse gas (GHG) emissions has demonstrated significant potential for mitigation, but suggests that the full mitigation will not be realized due to significant barriers to implementation. In this paper, we explore the constraints and barriers to implementation important for GHG mitigation in agriculture. We also examine how climate and non-climate policy in different regions of the world has affected agricultural GHG emissions in the recent past, and how it may affect emissions and mitigation implementation in the future. We examine the links between mitigation and adaptation and drives for sustainable development and the potential for agricultural GHG mitigation in the future.We describe how some countries have initiated climate and non-climate policies believed to have direct effects or synergistic effects on mitigating GHG emissions from agriculture. Global sharing of innovative technologies for efficient use of land resources and agricultural chemicals, to eliminate poverty and malnutrition, will significantly mitigate GHG emissions from agriculture.Previous studies have shown that as less than 30% of the total biophysical potential for agricultural GHG mitigation might be achieved by 2030, due to price- and non-price-related barriers to implementation. The challenge for successful agricultural GHG mitigation will be to remove these barriers by implementing creative policies. Identifying policies that provide benefits for climate, as well as for aspects of economic, social and environmental sustainability, will be critical for ensuring that effective GHG mitigation options are widely implemented in the future.  相似文献   

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This article examines farmers’ livelihood responses and vulnerability to climate variability and other stressors in Morogoro, Tanzania, to understand their implications for adaptation to climate change by agricultural households in developing world more generally. In Morogoro, agricultural households have extended cultivation, intensified agriculture, diversified livelihoods and migrated to gain access to land, markets and employment as a response to climatic and other stressors. Some of these responses have depleted and degraded natural resources such as forest, soil and water resources, which will complicate their living with climate change in the future. This will be particularly problematic to vulnerable groups such as women, children and pastoralists who have limited access to employment, markets and public services. In this light, fair adaptation to climate change by agricultural households in Morogoro and elsewhere in developing countries requires several complementary responses. Adaptation efforts should involve effective governance of natural resources because they function as safety nets to vulnerable groups. In addition, strengthening of national markets by infrastructure investments and institutional reforms is needed to give incentives to intensification and diversification in agriculture. Market participation also demands enhancement of human capital by public programs on health, education and wellbeing.  相似文献   

11.
粮食安全关系到中国稳定与发展和国际贸易秩序。以省级行政区为基本单位,基于2016—2018年各省份常住人口、农产品消费量、农业数据及相关参数,采用生态足迹和水足迹评价方法,在只考虑食用和再生产消费且不考虑地区耕地质量差异的条件下,核算各省份农产品自给的水土资源需求,评价中国省域水土资源承载力状态。结果显示:(1)中国现有耕地资源总量可满足自身耕地总需求(前者是后者1.81倍),但省际差异大,东部沿海省市耕地不足。(2)农业可用水资源总量亦可满足农业可持续生产需求,但区域严重不平衡,华北平原与宁夏水资源赤字严重,而青藏高原地区、长江以南省份农业可用水资源丰富。(3)水土资源空间不匹配制约了中国农业的粮食生产潜力,不考虑环境净化用水,水土资源匹配状态可满足全国粮食自给需求;但考虑环境净化用水,中国粮食难以实现自给,承载力赤字达33715.50万人。以资源环境可持续为导向,未来中国应从农业生产布局优化、农业结构调整、农业科技、产业与人口转移、农产品进口和农业国际合作等方面着手,解决中国农产品需求问题。  相似文献   

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In this paper, we investigate the ways in which climate stressors and economic changes related to liberalisation alter the local vulnerability context. Household and key informant data from two villages in Mozambique are analysed. First, we explore how changes such as increased market integration, altered systems of agricultural support, land tenure change and privatisation of agro-industries may affect factors important for response capacity, including access to local natural resources, employment opportunities, and household labour and capital. Next, we investigate how people related to the market while coping with the 2002–2003 drought. The study reveals that there had been an increase in informal trade and casual employment opportunities; however, market relations were very unfavourable and as the drought intensified, smallholders were locked into activities that barely secured economic survival and which sometimes endangered long-term response capacity. Only a few large-scale farmers had the capital and skills necessary to negotiate a good market position in urban markets, thus securing future incomes. Inequality, social sustainability, vulnerability and natural resource use are all closely linked in the savannas. Hence, both climate change adaptation policies and sustainability measures need to target vulnerability context and the social and environmental stressors shaping it.  相似文献   

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Agriculture is one of the most vulnerable sectors to climate change. The current vulnerability assessments through traditional fragmented sectoral methods are insufficient to capture the effects on complex agricultural systems. Therefore, the traditional methods need to be replaced by integrated approaches. The objective of this study is to propose a holistic vulnerability assessment method for agricultural systems. By aggregating both agro-ecological and socio-economic information, we develop an agricultural systems vulnerability index (ASVI) which allows for (i) a classification of geographical units according to their vulnerability level, (ii) an identification of key determinants of vulnerability for each unit and (iii) an assessment of adaptation policy scenarios considering their effects on the sustainability of the analysed systems. The proposed method is applied in the Khorezm region of Uzbekistan—a representative irrigated agricultural region in the lower Amu Darya river basin. A decision support tool is used to facilitate multi-criteria decision analysis, including the computation of the index and performing sensitivity analysis of the results. The assessment for Khorezm reveals significant spatial differences of vulnerability levels due to a variation of contributing factors, e.g. natural resources, water productivity, rural-urban ratio. It reveals also that feasible land and water management policies could reduce the vulnerability in Khorezm, particularly in the districts with the poorest agro-ecological conditions. Overall, the proposed method could support national and local authorities in the identification of sustainable adaptation policies for the agriculture sector.  相似文献   

14.
The ongoing drought in the Sahel region of West Africa highlights the vulnerability of food-producing systems to climate change and variability. Adaptation to climate should therefore increase the sustainability of agriculture under a long-term drought. Progress towards sustainability and adaptation in the the Senegal River Basin is hampered by an existing set of social and ecological relationships that define the control over the means of production and how people interact with their environment. These relationships are sensitive to the technological inputs and the administration of food production, or the factor bias in the different policy alternatives for rural development. One option is based on state-controlled, irrigated plantations to provide rice (Oryza) for the capital, Dakar. This policy emphasizes a top-down management approach, mechanized agriculture and a reliance on external inputs which strengthens the relationships introduced during the colonial period. A time series decomposition of the annual flow in the Senegal River at Bakel in Senegal suggests that water resources availability has been substantially curtailed since 1960, and a review of the water resources budget or availability in the basin suggests that this policy's food production system is not sustainable under the current climate of the basin. Under these conditions, this program is exacerbating existing problems of landscape degradation and desertification, which increases rural poverty. A natural resource management policy offers two adaptation strategies that favour decentralized management and a reduction of external inputs. The first alternative, “Les Perimetres Irrigués”, emphasizes village-scale irrigation, low water consumption cereal crops and traditional socio-political structures. The second alternative emphasizes farm-level irrigation and agro-forestry projects to redress the primary effects of desertification.  相似文献   

15.
Agricultural production systems can be viewed as consisting of three interrelated components: resources, technology, and environment (R-T-E). The quantities, qualities and terms of availability of resources condition the kinds of technology available to farmers and their choices among them. The technologies employed, in turn, may damage the environment, generating demands for policies to reduce the damages, and they also affect the future terms of availability of resources. The components of R-T-E systems are thus interdependent, and the relations among them change with time.In thinking about the future of world R-T-E systems in agriculture it is useful to group countries in four categories, given presently available technologies: (1) low productivity potential/high land potential; (2) high productivity potential/high land potential; (3) high productivity potential/low land potential; and (4) low productivity potential/low land potential. Given prospective increases in real prices, or scarcity of energy, fertilizer, and water for irrigation, farmers in Category 1 countries (e.g., the United States) are likely to respond by adopting more land-using technologies than in the past, and soil erosion is likely to be the most important resulting environmental problem. In Category 2 countries (e.g., Brazil) also, land-using technologies will appear attractive, but the use of agricultural chemicals will also increase sharply. Environmental problems of erosion, habitat loss and pesticide damage are likely to increase. Category 3 countries (e.g., India) will adopt more land-saving technologies despite rising prices of non-land inputs, and environmental problems associated with large irrigation systems are likely to become more important. The options for Category 4 countries (e.g., Western Europe) are more limited. The most likely response will be towards larger farms rather than major changes in technology. Environmental impacts of agriculture are not now of major importance in these countries and this is not likely to change.Governments have three broad options for dealing with energing problems of agricultural R-T-E systems. The traditional approaches rely on regulations or on a variety of financial inducements to move farmers towards more socially desirable patterns of resource use. A third, less traditional, approach is to invest in development of new technologies which simultaneously are economically attractive to farmers and less damaging to the environment.  相似文献   

16.
Socio-economic impacts of climate change on rural United States   总被引:4,自引:4,他引:0  
Directly or indirectly, positively or negatively, climate change will affect all sectors and regions of the United States. The impacts, however, will not be homogenous across regions, sectors, population groups or time. The literature specifically related to how climate change will affect rural communities, their resilience, and adaptive capacity in the United States (U.S.) is scarce. This article bridges this knowledge gap through an extensive review of the current state of knowledge to make inferences about the rural communities vulnerability to climate change based on Intergovernmental Panel on Climate Change (IPCC) scenarios. Our analysis shows that rural communities tend to be more vulnerable than their urban counterparts due to factors such as demography, occupations, earnings, literacy, poverty incidence, and dependency on government funds. Climate change impacts on rural communities differs across regions and economic sectors; some will likely benefit while others lose. Rural communities engaged in agricultural and forest related activities in the Northeast might benefit, while those in the Southwest and Southeast could face additional water stress and increased energy cost respectively. Developing adaptation and mitigation policy options geared towards reducing climatic vulnerability of rural communities is warranted. A set of regional and local studies is needed to delineate climate change impacts across rural and urban communities, and to develop appropriate policies to mitigate these impacts. Integrating research across disciplines, strengthening research-policy linkages, integrating ecosystem services while undertaking resource valuation, and expanding alternative energy sources, might also enhance coping capacity of rural communities in face of future climate change.  相似文献   

17.
To prepare agricultural systems for climate change, scientists need to be able to effectively engage with land managers and policy makers to explore potential solutions. An ongoing challenge in engagement is to distil the complexity of climate-change-management-change interactions in agro-ecological systems to identify responses that are most important for adaptation planning. This paper presents an approach for selecting climate change scenarios to provide a focal point for engaging with stakeholders to evaluate adaptation options and communicate assessment outcomes. We illustrate how scenarios selected with the approach can be used by evaluating climate change impacts and an adaptation option for livestock industries in the north-east Australian rangelands. Climate change impacts on forage production, animal liveweight gain and soil loss are found to track projected climate changes in four pasture communities; increasing by up to 50% and declining by up to 110% in response to doubled atmospheric carbon-dioxide (CO2), 4°C warming, and +20% to ?40% changes in mean annual rainfall. The effectiveness of reducing grazing pressure as an adaptation option shows a similar response; resulting in higher forage production (up to 40%), animal liveweight gains (up to 59%) and gross margins (up to 40%), and reduced soil erosion (down by 91%) per hectare relative to the baseline management. The results show that a few key scenarios may be selected to represent the range of global climate model (GCM) projections for use in assessing and communicating impacts and adaptation; simplifying the assessments and allowing limits to the effectiveness of adaptation options to be explored. The approach provides a framework for capturing and communicating trends in climate change impacts and the utility of options, which are required for successful engagement of stakeholders in finding viable adaption responses.  相似文献   

18.
Livestock production systems will inevitably be affected as a result of changes in climate and climate variability, with impacts on peoples’ livelihoods. At the same time, livestock food chains are major contributors to greenhouse gas emissions. Agriculture and livestock in particular will need to play a greater role than they have hitherto in reducing emissions in the future. Adaptation and mitigation may require significant changes in production technology and farming systems, which could affect productivity. Given what is currently known about the likely impacts on livestock systems, however, the costs of mitigating and adapting to climate change in the aggregate may not represent an enormous constraint to the growth of the global livestock sector, in its bid to meet increasing demand for livestock products. Different livestock systems have different capacities to adapt or to take on board the policy and regulatory changes that may be required in the future. Vulnerability of households dependent on livestock, particularly in the drier areas of developing countries, is likely to increase substantially, with concomitant impacts on poverty and inequity. The capacity of these systems to adapt and to yield up their carbon sequestration potential deserves considerable further study. Comprehensive frameworks need to be developed to assess impacts and trade-offs, in order to identify and target adaptation and mitigation options that are appropriate for specific contexts, and that can contribute to environmental sustainability as well as to poverty alleviation and economic development.  相似文献   

19.
粮食安全视角下的土地资源优化配置及其关键问题   总被引:2,自引:0,他引:2  
土地资源优化配置是提高土地资源利用效率、缓解土地用途冲突、促进人地和谐发展的重要手段。当前中国土地资源优化配置研究在理论探索与实践应用方面均取得积极进展,但面对土地利用急剧变化、土地管理效率低下及生态系统退化等现实问题,传统的以“数量—空间耦合”为核心的优化配置方式已难以满足当前人类追求美好生活的需求和国土空间可持续发展的目标要求。与此同时,全球粮食安全正面临一系列严峻挑战,土地资源优化配置将直接影响并作用于粮食生产与经济发展之间的冲突协调过程。改革开放以来,南京大学立足和服务于国家战略需求与重点区域发展(长三角及沿海地区),以保障资源安全与粮食安全目标为导向,围绕土地资源优化配置开展了大量研究和实践,主要集中在耕地利用格局优化、耕地集约利用转型、耕地保护与利用规划、土地利用与城乡规划、国土整治与农用地管理、土地利用制度创新、土地经济政策优化等特色研究领域,充分发挥地理学与管理学交叉学科优势,为国家土地资源优化与可持续利用的学科发展和制度创新做出了积极贡献。综上,通过系统梳理土地资源优化配置相关研究进展,总结归纳中国土地资源配置的关键问题,进一步在回顾南京大学学术贡献的基础上提出粮食安全视角下的中国土地资源优化配置面临的机遇与挑战,试图为可持续土地利用优化提供借鉴和参考。  相似文献   

20.
Climate change, land degradation and drought affect millions of people living in drylands worldwide. With its food security depending almost entirely on irrigated agriculture, Central Asia is one of the arid regions highly vulnerable to water scarcity. Previous research of land and water use in the region has focused on improving water-use efficiency, soil management and identifying technical, institutional and agricultural innovations. However, vulnerability to climate change has rarely been considered, in spite of the imminent risks due to a higher-than-average warming perspective and the predicted melting of glaciers, which will greatly affect the availability of irrigation water. Using the Khorezm region in the irrigated lowlands of northwest Uzbekistan as an example, we identify the local patterns of vulnerability to climate variability and extremes. We look at on-going environmental degradation, water-use inefficiency, and barriers to climate change adaptation and mitigation, and based on an extensive review of research evidence from the region, we present concrete examples of initiatives for building resilience and improving climate risk management. These include improving water use efficiency and changing the cropping patterns that have a high potential to decrease the exposure and sensitivity of rural communities to climate risks. In addition, changes in land use such as the afforestation of degraded croplands, and introducing resource-smart cultivation practices such as conservation agriculture, may strengthen the capacity of farmers and institutions to respond to climate challenges. As these can be out-scaled to similar environments, i.e. the irrigated cotton and wheat growing lowland regions in Central Asia and the Caucasus, these findings may be relevant for regions beyond the immediate geographic area from which it draws its examples.  相似文献   

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