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411.
The impacts of extreme weather events and climate variability on natural resource dependent farmers will further increase their vulnerability. This study describes how Adi farmers in Arunachal Pradesh (India) perceive and adapt to climate variability, and how this is influenced by gender and wealth. A total of 65 male and 71 female Adi farmers were interviewed or participated in focus group discussions. Both men and women have noticed there are fewer rainy days, longer summers, shorter winters and more erratic rainfall. However, some perceptions of change were gender and/or wealth class specific. Adi women noticed changes across areas they control including collecting forest foods, crop harvesting, and fermenting and storing of food. Men noted climate variability had made hunting wild game and marketing agricultural produce more difficult. Wealthy people were better placed to adapt to climate variability than poorer people because they could intensify their production systems. They switched to rainfed maize with improved varieties and horticultural cash crops which need more costly inputs. Wealthy people, particularly men, also received more advice and training than poorer people. Poorer farmers, particularly poor women, adapted predominantly by diversifying activities, such as using drought tolerant oil seeds and subsistence horticultural crops, accessing forest-based resources, rearing pigs and poultry, increasing fishing and the making of handicrafts. Storage, exchange and pooling of local resources were further strategies of the poor. This deeper understanding of Adi livelihood adaptation strategies will help increase their resilience by improving targeting of location specific extension services and adaptation policies.  相似文献   
412.
西安快速城市化边缘区社会脆弱性评价与影响因素   总被引:17,自引:7,他引:10  
脆弱性理论是分析人地相互作用程度、机理与过程的重要工具,为可持续性评估研究提供了新的视角。将社会脆弱性工具应用到城市边缘区研究中,视快速城市化为主要干扰,选取西安城市边缘区所辖街道为基本单元,从暴露度、敏感性、适应能力3方面构建社会脆弱性评价框架与指标体系,综合运用熵值法、函数模型法以及遥感与地理信息系统技术对社会脆弱性程度进行评价,揭示社会脆弱性空间分异格局,探究社会脆弱性关键影响因素及其影响机制。结果表明:① 西安城市边缘区的暴露度格局呈现出自中心向外围渐趋减缓的特征;敏感性程度的高、低分布与暴露度的低、高分布在空间上具有相似性;适应能力的空间规律性不明显;② 社会脆弱性空间分布不均衡,以中、低等级为主,低等级街道分布在城市内边缘区,中等级街道分散在城市外边缘区;③ 建设用地面积比重等8个因子对社会脆弱性有重要影响,土地利用方式与景观格局的变化以及物质与社会发展的不平衡是城市边缘区社会脆弱性形成的主要原因,社会系统体制转换阶段的差异进一步加剧了社会脆弱性;④ 城市边缘区应通过优化系统内部结构和功能以适应城市化的扰动,包括制定适应性管理政策和加强城市边缘区社会适应能力建设。  相似文献   
413.
As climate change continues to impact socio-ecological systems, tools that assist conservation managers to understand vulnerability and target adaptations are essential. Quantitative assessments of vulnerability are rare because available frameworks are complex and lack guidance for dealing with data limitations and integrating across scales and disciplines. This paper describes a semi-quantitative method for assessing vulnerability to climate change that integrates socio-ecological factors to address management objectives and support decision-making. The method applies a framework first adopted by the Intergovernmental Panel on Climate Change and uses a structured 10-step process. The scores for each framework element are normalized and multiplied to produce a vulnerability score and then the assessed components are ranked from high to low vulnerability. Sensitivity analyses determine which indicators most influence the analysis and the resultant decision-making process so data quality for these indicators can be reviewed to increase robustness. Prioritisation of components for conservation considers other economic, social and cultural values with vulnerability rankings to target actions that reduce vulnerability to climate change by decreasing exposure or sensitivity and/or increasing adaptive capacity. This framework provides practical decision-support and has been applied to marine ecosystems and fisheries, with two case applications provided as examples: (1) food security in Pacific Island nations under climate-driven fish declines, and (2) fisheries in the Gulf of Carpentaria, northern Australia. The step-wise process outlined here is broadly applicable and can be undertaken with minimal resources using existing data, thereby having great potential to inform adaptive natural resource management in diverse locations.  相似文献   
414.
Governments have a key role to play in the process of climate adaptation, through the development and implementation of public policy. Governments have access to a diverse array of instruments that can be employed to adapt their operations and influence the behaviour of individuals, organizations, and other governments. However, the choice of policy instrument is political, because it affects the distribution of benefits and costs, and entrenches institutional procedures and resources that are difficult to redeploy. This article identifies four key governing resources that governments employ in the service of adaptation and analyses these resources using criteria drawn from the policy studies literature. For each category, specific policy instruments are described, and examples are provided to illustrate how they have been used in particular jurisdictions. The article also discusses instrument selection, focusing on trade-offs among the instrument attributes, processes for setting the stage for instrument choice, jurisdictional constraints on instrument selection, and ways to avoid negative vertical and horizontal policy interplay.

Policy relevance

Adaptation is a nascent field of public policy, and courses of action to reduce vulnerability and build adaptive capacity are in their infancy. This article contributes to policy development and analysis by identifying the range of policy instruments available to governments and analysing concrete ways in which they are employed to implement adaptation policy objectives. Taking stock of these adaptation tools and comparing their behavioural assumptions and attributes helps to illuminate potential policy options, and to evaluate their technical viability, political acceptability, and economic feasibility. Providing examples of how these instruments have been implemented successfully in other jurisdictions offers ideas and lessons for public officials.  相似文献   

415.
Narrowing research and policy, while challenging, is especially important in climate change adaptation work (CCA) due to the high uncertainties involved in planning for climate change. This article aims to seek stakeholders’ opinions regarding how research and policy development can be bridged within the Cambodian water resources and agriculture sectors. The study used institutional ethnography methods with informants from government organizations, local academia, and development partners (DPs). This article identifies a number of challenges, and barriers for narrowing research–policy development gaps, including: limited effectiveness of governmental policies and planning; lack of relevant information required to promote evidence-based planning and policy development; and communication barriers. Evidence-based planning is valued by government officials most when there is actual and effective implementation of policies and plans. In practice, this often implies that governmental policies and plans need be scoped and scaled down to meet the available budget, and thus be achievable. In the long term, it also means building the capacity for policy-relevant research on climate change adaptation within Cambodia. Engaging policy stakeholders in research process for co-producing adaptation knowledge, and introducing knowledge intermediaries are suggested by informants as means to narrowing gaps between research and policy development. The presence of the Cambodia's Prime Minister in research–policy dialogues is recommended as important for attracting the attention of high-level policy makers.

Policy relevance

As a least developed and highly climate-vulnerable country, Cambodia has received climate change funding to implement a number of climate adaptation initiatives. Cambodia is likely to receive more climate change finance in the future. This article aims to assist evidence-based planning, in particular, through policy-relevant research on CCA, so that resources for adaptation in Cambodia are used effectively and efficiently. This research also directly benefits the sustainable development of the country.  相似文献   

416.
Growing attention to the impacts of climate change around the world has been accompanied by the profusion of discourses about the lives, livelihoods, and geographies that are “viable” and those that are not in the time of climate change. These discourses of viability often invoke concrete physical limits and tipping points suggesting a transcendent natural order. Conversely, I demonstrate how viability is co-produced through political economic structures that exercise power at multiple scales in shaping the environment and understandings of how it is changing. I describe three dialectics of this co-production: epistemic/material (between ideas about viability and their biophysical and political economic conditions), epistemic/normative (between how the world is understood to be and ideas about how we should live in it), and inter-scalar (between geographic scales, where action at one scale shapes both ecologies and understandings of possible action at another). Each of these dialectics shapes the knowledge regimes that govern the ambiguous social and biophysical process of disappearance and foreclosure of livelihood possibilities in the time of climate change. I examine these discourses of viability through narratives of unviable agrarian livelihoods in coastal Bangladesh, as a lens through which to examine the dialectics of viability more broadly. I situate these discourses concretely in relation to an analysis of interdisciplinary social and natural scientific research on ecological and agrarian viability in coastal Bangladesh now and in the future. Across a broad interdisciplinary spectrum, I find that scientific attention to political economy shapes the politics of possibility. Finally, I demonstrate how discourses of viability limit alternative possible economic and ecological futures. I do this through a concrete examination of the co-production of viable agrarian futures within communities in coastal Bangladesh. These alternative visions indicate that the viability of agriculture is shaped by historical and ongoing decisions in the present about cultivation, water management, and development intervention.  相似文献   
417.
解读政府间气候变化专门委员会(IPCC)第六次评估报告(AR6)粮食系统的影响与适应,对科学认识国际气候变化对农业影响学科前沿动态具有重要意义。最新发布的IPCC AR6在深化阐述粮食生产能力、种植布局、病虫害影响的基础上,高度确信人类活动导致的气候变暖对粮食系统产生了负面影响,论述了粮食运输及消费中的气候风险,解析了粮食生产-存储-运输-消费的全链条气候变化影响,延展了影响评估归因内容并丰富了农业环境影响等相关科学认识。对于粮食系统的适应能力,强调适应及减缓协同发展的气候恢复力发展路径,适应评估从适应能力、适应方式等理论逐步转向适应实施行动和成效评估,并注重适应行动的区域特异性和有效性。本次评估强调了气候变化对作物影响的检测和归因、关注了气候和农业环境变化复合影响、倡导基于生态系统的适应方案和技术,评估了现有适应技术的可行性和成效。报告内容对中国强化农业影响评估能力及把握国际学科动态具有参考价值。  相似文献   
418.
Interest in nature-based approaches for climate change adaptation in cities is growing. Whilst there is a growing field of scholarship in a European and North America setting, research on the policy and governance of urban greenspace for climate adaptation in subtropical Asia is limited. Given the different development patterns, environmental characteristics and governance arrangements in subtropical cities, plus their comparatively large population and high climate risk, this is a significant knowledge gap. In response, this paper evaluates competences – skill sets, capabilities, and supporting policy and legislation – to enact adaptation through greenspace across different governance contexts; and assesses how international rhetoric on nature-based adaptation becomes localised to subtropical Asian city settings. We conduct interviews with stakeholders, plus review of relevant policy and city-specific research, for three cities with different governance and development contexts: Hanoi (Vietnam); Taipei (Taiwan); and Fukuoka (Japan). Across all three cases, we find that institutional structures and processes for connecting different remits and knowledge systems are a bigger challenge than a lack of appropriate policy or individuals with the required technical knowledge. However, opportunities for civil society participation and consideration of justice issues vary between the cities according to the socio-political context. These findings illustrate the value of individuals and organisations able to work across institutional boundaries in linking greenspace and adaptation agendas for subtropical Asian cities; and the importance of competence in collaboration with developers and civil society so that the rapid development or regeneration seen in subtropical Asian contexts does not tend towards green climate gentrification. More broadly, our findings show that the diverse nature of subtropical Asian cities means the role of greenspace in climate adaptation is likely to be context-specific, and thus that caution must be exercised against uncritically importing best practices from exemplar cases elsewhere.  相似文献   
419.
The establishment of the South-Asian high (SAH) in April and May over the Indochina Peninsula (IP) is investigated based on the ERA-40 reanalysis data. The result shows that the SAH is generated and strengthened over the IP locally, rather than moving westward to the IP from the Western Pacific. After the SAH establishment the tropical upper tropospheric trough (TUTT) forms above the ocean to the east of the Philippines. We have found that the principal triggering factor of both the SAH construction and the TUTT formation is the variation in the Southern Asian atmospheric diabatic heating regime. In late April, both the climbing effect of Shan Plateau and the local surface sensible heating contribute to local rainfall over the IP. Then the local updraft and upper-air divergence are strengthened, being responsible for the SAH formed in the southern part of the IP. As convection moves northward along the Australian-Asian "maritime continent" and the Bay of Bengal (BoB) summer monsoon begins, the convection is intensified in May on the eastern BoB. The strong convection results in the SAH enhancing and expanding westward, accompanied by reinforced meridional flow to the east of SAH, where responses of the circulation to diabatic heating arrive at a quasi-steady state. Meanwhile, because of the positive geopotential vorticity advection resulting from upper equatorward flow, the local positive relative vorticity increases over the ocean to the east of the Philippines, making the tropical upper tropospheric trough (TUTT) form around 150°E.  相似文献   
420.
冰藻是南北极海冰生物群落中最主要的组成部分,通过固定和输出碳、吸收养分、生产释放氧气和有机化合物,推动高纬度生态系统的生物地球化学循环,在南北极海洋生态系统中发挥着重要作用。从宏观到微观综述了近年来在海冰栖息环境特征、冰藻种类组成和群落结构、冰藻对极端环境的适应机制以及气候变化对海冰环境和冰藻的影响等方面的研究进展,并以黑暗、寒冷和高盐为主要特征重点讨论了冰藻对海冰环境的生理和分子适应机制。提出在气候变化条件下,应进一步研究探索极地海冰环境基线、冰藻生物多样性组成和变化、冰藻代谢生理对环境的应对机制以及海冰生物之间的相互作用,以增进对当前和未来海冰生态系统和生物地球化学循环的理解。  相似文献   
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