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151.
Latin American smallholder coffee farmers linked with fair trade and organic markets are frequently cited as models for sustainable food systems. Yet many experience seasonal hunger, which is a very common, but understudied, form of food insecurity. Northern Nicaragua's highlands include well-organized cooperatives, high rural poverty rates, and rain dependent farms, offering a compelling study area to understand what factors are associated with seasonal hunger. This participatory mixed methods study combines data from observations, interviews and focus groups with results from a survey of 244 cooperative members. It finds that seasonal hunger is influenced by multiple factors, including: (1) annual cycles of precipitation and rising maize prices during the lean months; (2) inter annual droughts and periodic storms; and (3) the long-term inability of coffee harvests and prices to provide sufficient income. Sampled households experienced an average of about 3 months of seasonal hunger in 2009. A series of five least squares regression models find the expected significant impacts of corn harvest quantity, farm area, improved grain storage, and household incomes, all inversely correlated with lean months. Unanticipated results include the finding that households with more fruit trees reported fewer lean months, while the predominant environmentally friendly farming practices had no discernable impacts. The presence of hunger among producers challenges sustainable coffee marketing claims. We describe one example of a partnership-based response that integrates agroecological farm management with the use of fair trade cooperative institutions to re-localize the corn distribution system. Increased investments and integrated strategies will be needed to reduce threats to food security, livelihoods, and biodiversity associated with the rapid spread of coffee leaf rust and falling commodity prices.  相似文献   
152.
We develop a systems framework for exploring adaptation pathways to climate change among people in remote and marginalized regions. The framework builds on two common and seemingly paradoxical narratives about people in remote regions. The first is recognition that people in remote regions demonstrate significant resilience to climate and resource variability, and may therefore be among the best equipped to adapt to climate change. The second narrative is that many people in remote regions are chronically disadvantaged and therefore are among the most vulnerable to climate change impacts. These narratives, taken in isolation and in extremis, can have significant maladaptive policy and practice implications. From a systems perspective, both narratives may be valid, because they form elements of latent and dominant feedback loops that require articulation for a nuanced understanding of vulnerability-reducing and resilience-building responses in a joint framework. Through literature review and community engagement across three remote regions on different continents, we test the potential of the framework to assist dialogue about adaptation pathways in remote marginalized communities. In an adaptation pathway view, short-term responses to vulnerability can risk locking in a pathway that increases specific resilience but creates greater vulnerability in the long-term. Equally, longer-term actions towards increasing desirable forms of resilience need to take account of short-term realities to respond to acute and multiple needs of marginalized remote communities. The framework was useful in uniting vulnerability and resilience narratives, and broadening the scope for adaptation policy and action on adaptation pathways for remote regions.  相似文献   
153.
王盛泽 《华南地震》2010,30(1):82-91
从历史最大地震烈度分布图分析,可知揭阳、汕头、潮州三市位于Ⅶ~Ⅷ度高地震烈度区。该城市群地震灾害有以下特点:市区发生破坏性地震的潜在危险性大;地震时市区地震烈度高,地震灾害大,损失严重。采用宏观经济易损性的地震损失分析方法,重演该区的历史破坏性地震。分析表明:抓好该区的防震减灾工作是保持社会和经济建设持续发展的一项重要工作。  相似文献   
154.
汶川地震后,作者赴陇南文县、武都区、康县、成县等地详细调查了房屋建筑的震害情况。在整理分析了大量现场第一手资料后,分别建立了各类房屋的地震易损性矩阵,并列举了一些典型震害现象,可为汶川地震后灾区的重建工作提供一定的参考。  相似文献   
155.
This paper deals with the development of a procedure aimed at defining a seismic risk mitigation strategy for public buildings in terms of prioritization, time required and funds. The procedure is based on a global risk index involving the entire building stock under study thus facilitating an examination of risk variation over time up to its final value. Relationships between the current seismic capacity–demand ratios and the required strengthening costs (cost models) have been developed. Each of the assumed cost models has a different target in terms of capacity–demand ratio to be obtained after strengthening, basically ranging between full retrofit and upgrading. The procedure has been applied to 69 hospital buildings located in Basilicata region for which the vulnerability data was available as a result of a large assessment program set up by the regional government. Priorities have been defined on the basis of seismic capacity, local hazard and number of human beings possibly involved (exposure). The results of different strengthening strategies have been outlined with a special focus on the pros and cons of the upgrading strategy with respect to various retrofit strategies. The procedure may be applied to different categories of public buildings by properly modifying some input parameters and partially redefining criteria for prioritization.  相似文献   
156.
A GIS-oriented procedure that may partially illuminate the consequences of a possible earthquake is presented in two main steps (seismic microzonation and vulnerability steps) along with its application in Tabriz (a city in NW Iran). First, the detailed geological, geodetical, geotechnical and geophysical parameters of the region are combined using an Analytic Hierarchy Process (AHP) and a deterministic near-field earthquake of magnitude 7 in the North Tabriz Fault is simulated. This simulation provides differing intensities of ground shaking in the different districts of Tabriz. Second, the vulnerability of buildings, human losses and basic resources for survivors is estimated in district two of the city based on damage functions and relational analyses. The results demonstrate that 69.5% of existing buildings are completely destroyed, and the rate of fatalities is approximately 33% after a nighttime scenario. Finally, the same procedure was applied to an actual earthquake (first event on the 11th of August, 2012 of the Ahar twin earthquakes) to validate the presented model based on two aspects: (1) building damages and (2) seismic intensity.  相似文献   
157.
The poverty implications of climate-induced crop yield changes by 2030   总被引:1,自引:0,他引:1  
Accumulating evidence suggests that agricultural production could be greatly affected by climate change, but there remains little quantitative understanding of how these agricultural impacts would affect economic livelihoods in poor countries. Here we consider three scenarios of agricultural impacts of climate change by 2030 (impacts resulting in low, medium, or high productivity) and evaluate the resulting changes in global commodity prices, national economic welfare, and the incidence of poverty in a set of 15 developing countries. Although the small price changes under the medium scenario are consistent with previous findings, we find the potential for much larger food price changes than reported in recent studies which have largely focused on the most likely outcomes. In our low-productivity scenario, prices for major staples rise 10–60% by 2030. The poverty impacts of these price changes depend as much on where impoverished households earn their income as on the agricultural impacts themselves, with poverty rates in some non-agricultural household groups rising by 20–50% in parts of Africa and Asia under these price changes, and falling by significant amounts for agriculture-specialized households elsewhere in Asia and Latin America. The potential for such large distributional effects within and across countries emphasizes the importance of looking beyond central case climate shocks and beyond a simple focus on yields – or highly aggregated poverty impacts.  相似文献   
158.
We review five perspectives on human vulnerability to environmental change—biophysical, human ecological, political economy, constructivist and political ecology—and assess their respective strengths and weaknesses. While each of these perspectives offers important insights, and some theoretical convergence is evident, the field remains divided along a number theoretical fracture lines. Two deeply rooted metatheoretical assumptions—essentialism and nominalism—are hindering the construction of a more integrated perspective on vulnerability, one capable of addressing the interrelated dynamics of social structure, human agency and the environment. We conclude by suggesting that an evolutionary perspective on social change, grounded in a critical realist epistemology, provides the best prospect for avoiding the above pitfalls and advancing our understanding of vulnerability.  相似文献   
159.
This article presents evidence on two distinct farming systems—one that utilizes common property pasturelands and another based on private pasturelands—in the Brazilian semi-arid zone. The research is based on a survey carried out in the state of Bahia in 2002. A bivariate analysis was carried out to compare agricultural outputs and income generated in each system. Data suggest that there are no significant differences between the two groups concerning income generation. However, farmers using common pasturelands have more diversified systems and invest more on small-animal husbandry, which are adapted to the dry environment. As a consequence, families that use common pasturelands have a higher consumption of animal protein. These families are thus not necessarily more vulnerable to droughts than those with private pasturelands. Formulating effective institutions to control access to the commons is a strategy pursued by some communities, yet, their ecological sustainability is still unknown.  相似文献   
160.
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