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591.
Small-scale inland capture fisheries provide an important source of nutritious food, employment and income to millions of people in developing countries, particularly in rural environments where limited alternatives exist. However, the sector is one of most under-valued fisheries sectors and is increasingly experiencing environmental change. This study adopts a Sustainable Livelihoods Approach and investigates how important a fluctuating inland fishery is to livelihoods, and how local perceptions on challenges corresponds to global evidence. Through an innovative participatory method; photovoice, the lived experiences and perceptions of fishers are depicted. The findings illuminate the valuable role of the sector to food and nutrition security and the complex nexus with vulnerability to climate change. The study responds to the call for more local level assessments of the impacts of climate change on inland fisheries in data-limited environments, and the value of the sector in underpinning the Sustainable Development Goals. Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01583-1.  相似文献   
592.
Soil erosion on agricultural land is a growing problem in Western Europe and constitutes a threat to soil quality and to the ability of soils to provide environmental services. The off-site impacts of runoff and eroded soil, principally eutrophication of water bodies, sedimentation of gravel-bedded rivers, loss of reservoir capacity, muddy flooding of roads and communities, are increasingly recognised and costed. The shift of funding in the European Union (EU) from production-related to avoidance of pollution and landscape protection, raises issues of cross-compliance: public support for agriculture has to be seen to give value-for-money. In this context risk-assessment procedures have been introduced to help farmers recognise sites where either certain crops should not be grown or anti-erosion measures are required. In England, Defra [Defra, 2005a. Controlling Soil Erosion: a Manual for the Assessment and Management of Agricultural Land at Risk of Water Erosion in Lowland England. Revised September 2005. Department for Environment, Food and Rural Affairs, London] sets out a system of risk-assessment, including ranking of crops susceptible to erosion and anti-erosion measures, that may be selected. We assess this system using field data for an area of erodible soils in the Rother valley, Sussex. The Defra approach correctly identifies most at-risk fields and, taken together with land-use maps, allows non-compliance with advice to be highlighted. We suggest a simple extension to the system which would further identify at-risk fields in terms of possible damage to roads and rivers from muddy runoff. The increased risk of erosion in the study area is associated with certain crops: potatoes, winter cereals, maize and grazed turnips and seems unlikely to be the result of changes in rainfall which over the last 130 years are minimal. We have not evaluated proposed anti-erosion measures in the area because few have been put into practice. The European Water Framework Directive will increasingly focus attention on agricultural fields as a source of river pollution. Assessing the risk of erosion and the need for field testing of suggested approaches, are not simply issues for the EU, but for the management of global agricultural systems.  相似文献   
593.
In this study, the authors investigate farmers’ vulnerability to climate variability and evaluate local adoption of technology and farmers’ perceptions of adaptation strategies to rainfall variability and policies. A survey was conducted in a community in northern Burkina Faso following the crop failure of 2004. In 2006, following a better harvest, another survey was conducted to compare farmers’ actions and reactions during two contrasted rainy seasons. The results confirm that farmers from this community have substantially changed their practices during the last few decades. They have adopted a wide range of techniques that are intended to simultaneously increase crop yield and reduce yield variability. Micro water harvesting (Zaï) techniques have been widely adopted (41%), and a majority of fields have been improved with stone lines (60%). Hay (48%) and sorghum residues are increasingly stored to feed animals during the dry season, making bull and sheep fattening now a common practice. Dry season vegetable production also involves a majority of the population (60%). According to farmers, most of the new techniques have been adopted because of growing land scarcity and new market opportunities, rather than because of climate variability. Population pressure has reached a critical threshold, while land scarcity, declining soil fertility and reduced animal mobility have pushed farmers to intensify agricultural production. These techniques reduce farmers’ dependency on rainfall but are still insufficient to reduce poverty and vulnerability. Thirty-nine percent of the population remains vulnerable after a good rainy season. Despite farmers’ desire to remain in their own communities, migrations are likely to remain a major source of regular income and form of recourse in the event of droughts.  相似文献   
594.
In this article, we argue that people’s adjustments to multiple shocks and changes, such as conflict and drought, are intrinsically political processes that have uneven outcomes. Strengthening local adaptive capacity is a critical component of adapting to climate change. Based on fieldwork in two areas in Kenya, we investigate how people seek to access livelihood adjustment options and promote particular adaptation interests through forming social relations and political alliances to influence collective decision-making. First, we find that, in the face of drought and conflict, relations are formed among individuals, politicians, customary institutions, and government administration aimed at retaining or strengthening power bases in addition to securing material means of survival. Second, national economic and political structures and processes affect local adaptive capacity in fundamental ways, such as through the unequal allocation of resources across regions, development policy biased against pastoralism, and competition for elected political positions. Third, conflict is part and parcel of the adaptation process, not just an external factor inhibiting local adaptation strategies. Fourth, there are relative winners and losers of adaptation, but whether or not local adjustments to drought and conflict compound existing inequalities depends on power relations at multiple geographic scales that shape how conflicting interests are negotiated locally. Climate change adaptation policies are unlikely to be successful or minimize inequity unless the political dimensions of local adaptation are considered; however, existing power structures and conflicts of interests represent political obstacles to developing such policies.  相似文献   
595.
The aggressive traffic interventions and emission control measures implemented to improve air quality during the 2008 Beijing Olympic Games created a valuable case study to evaluate the effectiveness of these measures on mitigating air pollution and protecting public health. In this paper, we report the results from our field campaign in summer 2008 on the on-road emission factors of carbon monoxide, black carbon (BC) and ultrafine particles (UFP) as well as the ambient BC concentrations. The fleet average emission factors for light-duty gasoline vehicles (LDGV) showed considerable reduction in the Olympic year (2008) compared to the pre-Olympic year (2007). Our measurement of Black Carbon (BC), a primary pollutant, at different elevations at the ambient site suggests consistent decrease in BC concentrations as the height increased near the ground level, which indicates that the nearby ground level sources, probably dominated by traffic, contributed to a large portion of BC concentrations in the lower atmospheric layer in Beijing during summertime. These observations indicate that people living in near ground levels experience higher exposures than those living in higher floors in Beijing. The BC diurnal patterns on days when traffic control were in place during the Olympic Games were compared to those on non-traffic-control days in both 2007 and in 2008. These patterns strongly suggest that diesel trucks are a major source of summertime BC in Beijing. The median BC concentration on Olympic days was 3.7 μg m−3, which was dramatically lower than the value on non-traffic-control days, indicating the effectiveness of traffic control regulations in BC reduction in Beijing.  相似文献   
596.
Impinging local environmental problems on the one hand and constantly persuasive climate change concerns on the other put developing Asian cities in a dilemma as to which direction they should channel their efforts. While local matters are their immediate mandate, increasing awareness of climate change vulnerabilities adds weight to global problems. In this context, the concepts of co-benefits and ancillary benefits play an important role in aligning climate change concerns into sector-specific developmental goals. This article presents the conceptual aspects of co-benefits and the integration of climate concerns into sustainable development goals. The possible synergies between these two different but very important strategic pathways are examined along with possible ways to align them. The bottlenecks that can occur during such integration are also highlighted.  相似文献   
597.
Animal wastewater lagoons nearby concentrated animal feeding operations (CAFOs) represent the latest tendency in global animal farming, severely impacting the magnitude of greenhouse gas emissions, including nitrous oxide (N2O). We hypothesized that lagoon wastewater could be supersaturated with N2O as part of incomplete microbial nitrification/denitrification processes, thereby regulating the N2O partitioning in the gaseous phase. The objectives of this study were: (i) to investigate the magnitude of dissolved N2O concentrations in the lagoon; and (ii) to determine the extent to which supersaturation of N2O occurs in wastewater lagoons. Dissolved N2O concentrations in the wastewater samples were high, ranging from 0.4 to 40.5 μg N2O mL−1. Calculated dissolved N2O concentrations from the experimentally measured partition coefficients were much greater than those typically expected in aquatic systems (<∼0.6 μg N2O mL−1). Knowledge of the factors controlling the magnitude of N2O supersaturation could potentially bridge mass balance differences between in situ measurements and global N2O models.  相似文献   
598.
This paper develops a conceptual model to examine the vulnerability of Inuit food systems to food insecurity as a consequence of climate change. The model illustrates that food system vulnerability is determined by the exposure and sensitivity of the food system to climate-related risks and its adaptive capacity to deal with those risks. The model is empirically applied using a case study from Igloolik, Nunavut. Specifically, the paper focuses on how extreme climate-related conditions in 2006 interacted with the food system to affect food security, using 2006 as a lens to identify and characterize some of the processes and conditions shaping vulnerability, and establishing a baseline for identifying and characterizing processes that are likely to shape future vulnerability. There is a high level of adaptive capacity among Igloolik Inuit, with food sharing mechanisms, hunting flexibility, and store-food access moderating the impact of climatic-risks on food security. However, high fuel and commodity prices, the increasing economic burden of adapting to back-to-back years with unfavorable climatic conditions, underlying community vulnerabilities, and the nature to the climate extremes in 2006, overwhelmed the adaptive capacity of many community members. Those dependent on traditional foods and having limited access to financial resources were particularly vulnerable.  相似文献   
599.
This paper examines the environment-income relationship in the context of the Environmental Kuznets Curve (EKC), and explores the possible role that factors like governance, political institutions, socioeconomic conditions, and education play in influencing this relationship. The results suggest that the EKC exists for carbon dioxide emissions for cross-country data over the period 1984–2002. However, there is nothing automatic about this relationship; policies designed to protect the environment may be responsible for this phenomenon. Two other significant findings are: one, countries with better quality of governance, stronger political institutions, better socioeconomic conditions and greater investment in education have lower emissions; and two, only around 15% of the countries in the dataset have reached income levels high enough to be associated with an unambiguous decline in emissions. The implications of these results are discussed within the context of the international environmental policy arena and the Kyoto Protocol. One of the main objectives of this paper is to bridge the gap between studies conducted on the EKC and developments in the international environmental policy arena. As a final note this paper emphasizes that one needs to connect the body of knowledge on the EKC hypothesis to the international environmental policy arena, despite the apparent difficulty of doing so. One hopes that future studies will further build on this line of thought.
Kuheli DuttEmail:
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600.
集中连片贫困地区扶贫开发与农户脱贫问题关系社会稳定与和谐,而恢复力概念为贫困领域研究提供了新的视角。研究利用抽样调查的321户家庭问卷数据,基于生计恢复力理论框架,构建农户贫困恢复力指标体系,从农户家庭结构分类出发,采用探索性统计和主成分分析判定不同人口、生计结构农户缓冲力资本、贫困恢复力差异,运用多层次模型探究农户家庭因素(生计、人口)与贫困恢复力内在结构效应。研究主要结论:1研究区不同家庭结构农户经济类资本分布极不均衡,资本积累水平低;2影响贫困地区农户个体恢复力的主要因素包括物质资本、经济收入、文化教育、劳动力、交通条件、社会资源等;3高质量劳动力人口结构以及合理多样化收入方式的生计结构对农户贫困恢复力才具有正向效应。最后,针对研究区农户家庭结构贫困恢复力差异和关键影响因子,提出相关恢复力建设对策。  相似文献   
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