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231.
流域水质目标管理的风险识别与对策研究   总被引:3,自引:1,他引:2  
以水质目标为约束和核心的管理将逐步完善、补充和强化当前的总量控制模式,成为我国中长期流域水环境管理的重要内容.流域水质目标管理是一个"响应→调控"并不断反馈调整的过程,但由于流域系统的非线性和不确定性,流域污染减排并不能完全确保水质目标的实现.本文将这种由不确定性而引致的流域水质目标的不完全可达性界定为风险,并在分析流域水质目标管理框架思路的基础上,识别并实证了水质目标管理中的主要风险来源,主要包括:1在"响应"层面,由于水质响应与负荷削减等措施间的非线性、时滞性、指标不协同等不对应关系带来的风险;2在"调控"层面,由于水环境管理缺乏适应性的调控和反馈机制而产生的水质达标风险.在此基础上,提出了流域水质目标风险管理的转变途径及其定量表征方法,以期为流域水质目标风险管理提供借鉴.  相似文献   
232.
中国水资源管理适应气候变化的研究综述   总被引:1,自引:0,他引:1  
以全球变暖为特征的气候变化已成为当今科学界、各国政府和社会公众普遍关注的最重要议题之一。气候变化对水资源管理的影响是具有重要学术价值的新兴研究方向,目前的重点研究领域主要包括:气候变化背景下水资源综合管理方式与集成研究,气候变化下水资源适应性管理机制,中国面临的水资源均衡性管理,公众参与水资源适应性管理的政策制定,对减缓措施与水资源可持续发展的认识。主要的研究方法包括:适应气候变化的定性分析方法(多尺度适应综合分析方法)、成本效益分析方法等。适应性管理是目前应对气候变化伴随的不确定性问题的有效策略,未来应在分析中国各流域水资源不确定性问题的基础上,建立气候变化情景下适应气候变化的水资源适应性管理体制机制。  相似文献   
233.
This paper explores the perceptions of policy makers and rural agricultural producers in respect of policy framing and adaptation to climate change, social learning and stakeholder input (participation) surrounding two successful agri-environmental programmes in Saskatchewan, Canada. Given the record of success of these two programmes in reducing vulnerability to climate change, this study provides an opportunity to explore certain attributes of adaptive management, including: what attributes make policy and programmes responsive; how government can frame programmes facilitating adaptation to climate change; what types of mechanisms can or should be used to engage with producers; and perhaps most importantly, what producers expect of government, government policies and programmes in relation to adaptation to climate change.  相似文献   
234.
This paper examines the challenges of achieving sustainable management of the world's largest mangrove forest, the Sundarbans (SMF) in Bangladesh. During the past two decades, conflicts between mangrove maintenance and the pressure to provide economic livelihoods to forest-dependent communities (FDCs) have emerged and persisted. The SMF is currently managed by the Bangladesh Forest Department (BFD) under a state property rights regime. This study explores an alternative property rights regime which includes participatory approaches and co-management with FDCs to achieve sustainability, both economically and environmentally. Focus group discussions and a survey were the methods used to assess the prospects. The study finds that the absence of a management partnership between the BFD and FDCs is mainly responsible for the policy failures to achieve sustainable management of the SMF. However, evidence is presented that a ‘co-management’ property rights regime cannot be established until FDC capacity is enhanced through the formation of community level institutions.  相似文献   
235.
旅游地可持续发展需要重点关注当地居民生计的可持续。以海螺沟景区为案例地,基于可持续生计框架构建了适用的生计资本评估指标体系,量化识别了景区农户可持续的生计方式,明确了影响两类脆弱性农户生计策略选择的主要因素。结果表明:在研究区六种生计方式中,采用均衡兼收型和旅游主营型策略的农户其生计资本水平最高,而传统务农型和务工型农户生计资本水平最低。不同生计策略类型的农户在空间上集聚分布。缺乏金融资本是影响传统务农型和务工型农户选择均衡兼收型生计策略的主要因素,而物质资本和社会资本的缺乏则对他们选择旅游主营型生计策略有显著的影响。此外,海拔、距公路和核心景点的距离也对农户生计策略的选择有重要影响。  相似文献   
236.
Nicaragua is one of the four countries most affected by climate change, and coffee production is expected to vastly shrink in some critical areas. This can have considerable effects on social structure since nearly a third of its working population depend on coffee for a living. Social perceptions of climate change and water pressures are a key issue in the public's acceptance of adaptation measures. Furthermore, the existing risk for crop production is not necessarily correlated with the farmers’ awareness of that threat. This paper focuses on coffee producers’ perception of risk and adaptive capacity for coffee crops in Nicaragua in response to climate change and water availability. We aim to analyze how dependent the producers are on water resources, and if this reliance affects their perception of risk and their expectations with regard to public and private support for dealing with adaptation. A survey of 212 representative farmers of the national population of farms in the country's two most important production areas was conducted for this purpose. We consider socio-economic and biophysical variables to explain the farmers’ perceptions. Our findings show that experience and technical capacity are relevant to the adaptive capacity although smallholders do not always show high concern and their expectations with regard to external support are very low. The paper can be useful to prioritize the measures necessary for a greater level of involvement from stakeholders.  相似文献   
237.
Abstract: Conservation actions need to account for and be adapted to address changes that will occur under global climate change. The identification of stresses on biological diversity (as defined in the Convention on Biological Diversity) is key in the process of adaptive conservation management. We considered any impact of climate change on biological diversity a stress because such an effect represents a change (negative or positive) in key ecological attributes of an ecosystem or parts of it. We applied a systemic approach and a hierarchical framework in a comprehensive classification of stresses to biological diversity that are caused directly by global climate change. Through analyses of 20 conservation sites in 7 countries and a review of the literature, we identified climate‐change‐induced stresses. We grouped the identified stresses according to 3 levels of biological diversity: stresses that affect individuals and populations, stresses that affect biological communities, and stresses that affect ecosystem structure and function. For each stress category, we differentiated 3 hierarchical levels of stress: stress class (thematic grouping with the coarsest resolution, 8); general stresses (thematic groups of specific stresses, 21); and specific stresses (most detailed definition of stresses, 90). We also compiled an overview of effects of climate change on ecosystem services using the categories of the Millennium Ecosystem Assessment and 2 additional categories. Our classification may be used to identify key climate‐change‐related stresses to biological diversity and may assist in the development of appropriate conservation strategies. The classification is in list format, but it accounts for relations among climate‐change‐induced stresses.  相似文献   
238.
Despite widespread recognition of the major threat to tropical forest biological diversity and local food security posed by unsustainable bushmeat hunting, virtually no long‐term studies tracking the socioecological dynamics of hunting systems have been conducted. We interviewed local hunters and collected detailed hunting data to investigate changes in offtake and hunter characteristics over 10 years (2001–2010) in Dibouka and Kouagna villages, central Gabon, in the context of hunter recollections of longer term trends since the 1950s. To control for changes in hunter behavior, such as trap location and characteristics, we report hunting offtake data per trap. Our results suggest the hunting area was already highly depleted by 2001; local hunters reported that 16 large‐bodied prey species had become rare or locally extirpated over the last 60 years. Overall, we observed no significant declines in hunting offtake or changes in species composition from 2001 to 2010, and offtakes per trap increased slightly between 2004 and 2010. However, trapping distance from the villages increased, and there was a switch in hunting techniques; a larger proportion of the catch was hunted with guns in 2010. The number of hunters declined by 20% from 2004 to 2010, and male livelihood activities shifted away from hunting. Hunters with the lowest hunting incomes in 2004 were more likely than successful hunters to have moved away from the village by 2010 (often in response to alternative employment opportunities). Therefore, changes in trap success (potentially related to biological factors) were interacting with system‐level changes in hunter number and composition (related to external socioeconomic factors) to produce a relatively static overall offtake. Our results highlight the importance of understanding the small‐scale context of hunting to correctly interpret changes or apparent stasis in hunting effort and offtake over time. Cambio Social y Ecológico a lo Largo de Una Década en un Sistema de Cacería Aldeana, Gabón Central  相似文献   
239.
Abstract: In many areas of the developing world, the establishment of permanent marine reserves is inhibited by cultural norms or socioeconomic pressures. Community conserved areas that are periodically harvested are increasingly being implemented as fisheries management tools, but few researchers have empirically compared them with permanently closed reserves. We used a hierarchal control‐impact experimental design to compare the abundance and biomass of reef fishes, invertebrates, and substrate composition in periodically harvested and permanent reserves and in openly fished (control sites) of the South Pacific island country of Vanuatu. Fished species had significantly higher biomass in periodically harvested reserves than in adjacent openly fished areas. We did not detect differences in substratum composition between permanent reserves and openly fished areas or between permanent reserves and periodically harvested reserves. Giant clams (tridacnids) and top shells (Trochus niloticus) were vulnerable to periodic harvest, and we suggest that for adequate management of these species, periodically harvested community conservation areas be used in conjunction with other management strategies. Periodic harvest within reserves is an example of adaptive and flexible management that may meet conservation goals and that is suited to the social, economic, and cultural contexts of many coastal communities in the developing world.  相似文献   
240.
Buzz Sharp 《Disasters》2007,31(S1):S104-S123
In the post-Comprehensive Peace Agreement (CPA) era a greater impact on the unacceptably high prevalence of child malnutrition is more likely to come from additional investment and attention to education, health, hygiene, sanitation and childcare practices than from expanded food aid interventions. The negligible impact of food aid on malnutrition, although most commonly challenged on the quality of needs assessments, is equally attributable to the timing of deliveries, and a dysfunctional distribution system. Comparatively few resources have been allocated to strengthen skills for assessing, analysing and understanding community priorities, local economies, and social safety nets. A more thoughtful allocation of scarce funds could have more impact if a range of alternative responses was considered. Participation in and commitment to a more independent livelihoods analytical forum would improve communication with the new government, local leaders and other partners, as well as providing a platform for reaching consensus on both humanitarian and development planning over the next five years.  相似文献   
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