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331.
基于Vague集的城市地震灾害综合脆弱性度量及其应用 总被引:1,自引:0,他引:1
贾增科 《中国安全科学学报》2012,22(4):3-7
为度量城市地震灾害综合脆弱性及灾害中生命及财产的可挽救性,将社会脆弱性、应急系统脆弱性引入城市综合脆弱性研究。利用Vague集的相似度量理论,构建基于Vague集的城市地震灾害综合脆弱性度量模型;扩展可挽救性的概念,建立基于综合脆弱性度量的城市地震灾害可挽救性度量模型。以2003年日本北海道地震损失为标准,通过上述2个模型,得到某城市地震灾害综合脆弱度为2.76×10-4,可挽救度分别为:死亡人数减少18人、重伤人数减少72人、直接经济损失减少0.2亿元人民币。 相似文献
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333.
干旱区内陆河流域景观生态建设 总被引:3,自引:1,他引:3
干旱区内陆河流域因其干旱、风沙及盐碱的自然环境,加之盲目开垦荒地、不合理利用水资源等人为因素的影响,改变了原有的生态平衡,形成了脆弱的生态环境和特殊的景观格局。其景观呈现出以荒漠为基质,河流廊道为核心对称分布的水域湿地-林(草)地-荒漠的宏观局格。由于水是干旱区内陆河流域的关键因素,为了合理利用水资源,积极发挥人的作用,从景观生态学理论与方法的角度,提出了以河流廊道建设、植被景观建设、绿洲景观建设为核心的生态建设方案,以增加内陆河流域整个生态体系的容载力和稳定性。 相似文献
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335.
基于广西河池市胁迫风险的土壤环境脆弱性评价 总被引:1,自引:0,他引:1
采用层次分析法划分了土壤环境各因素的敏感性和重要程度,从而建立起能科学表达土壤环境承载能力的土壤环境脆弱性评价体系。基于广西河池市指标数据,借助地理信息系统软件Arc GIS9.3、ENVI5.1、MATLAB7.0等计算平台对空间数据进行模型训练与验证,得出可视化表征土壤环境脆弱性空间分布状况的评价图件。结果表明,河池市北部、南部存在高度脆弱区,占全市国土面积的36.3%,中度脆弱区占38.3%,低度脆弱区占25.4%。总体来看,河池市大部分区域的土壤环境属中高度脆弱。 相似文献
336.
区域地下水污染风险评价方法研究 总被引:11,自引:8,他引:11
依据系统风险评价的边界要素,初步建立了区域地下水污染风险评价指标体系:区域地下水特殊脆弱性评价、区域污染源特性评价和区域特征污染物健康风险评价.采用多指标综合方法,对3个评价体系进行耦合,并运用ArcMap的Spatial Analysis功能制图对其进行风险表征,从而建立了对不同地区不同自然条件、不同污染类型的区域地下水污染风险评价的新方法.以常州市为例,利用该方法对其浅层地下水进行污染风险评价,研究表明该市地下水脆弱性指数较高,且分布不均;污染源分布较为集中,对地下水污染风险影响较大;受污染物及污染源影响,常州市区人群健康风险值较高.全市浅层地下水污染风险高且分布不均,污染风险较高区域分布在安家-薛家-郑陆一线以北和城区及其东南部一带. 相似文献
337.
Traps and transformations influencing the financial viability of tourism on private‐land conservation areas 下载免费PDF全文
The ability of private conservation organizations to remain financially viable is a key factor influencing their effectiveness. One‐third of financially motivated private‐land conservation areas (PLCAs) surveyed in South Africa are unprofitable, raising questions about landowners’ abilities to effectively adapt their business models to the socioeconomic environment. In any complex system, options for later adaptation can be constrained by starting conditions (path dependence). We tested 3 hypothesized drivers of path dependence in PLCA ecotourism and hunting business models: (H1) the initial size of a PLCA limits the number of mammalian game and thereby predators that can be sustained; (H2) initial investments in infrastructure limit the ability to introduce predators; and (H3) rainfall limits game and predator abundance. We further assessed how managing for financial stability (optimized game stocking) or ecological sustainability (allowing game to fluctuate with environmental conditions) influenced the ability to overcome path dependence. A mechanistic PLCA model based on simple ecological and financial rules was run for different initial conditions and management strategies, simulating landowner options for adapting their business model annually. Despite attempts by simulated landowners to increase profits, adopted business models after 13 years were differentiated by initial land and infrastructural assets, supporting H1 and H2. A conservation organization's initial assets can cause it to become locked into a financially vulnerable business model. In our 50‐year simulation, path dependence was overcome by fewer of the landowners who facilitated natural ecological variability than those who maintained constant hunting rates and predator numbers, but the latter experienced unsustainably high game densities in low rainfall years. Management for natural variability supported long‐term ecological sustainability but not shorter term socioeconomic sustainability for PLCAs. Our findings highlight trade‐offs between ecological and economic sustainability and suggest a role for governmental support of the private conservation industry. 相似文献
338.
Effects of temperature and precipitation on grassland bird nesting success as mediated by patch size 下载免费PDF全文
Grassland birds are declining faster than any other bird guild across North America. Shrinking ranges and population declines are attributed to widespread habitat loss and increasingly fragmented landscapes of agriculture and other land uses that are misaligned with grassland bird conservation. Concurrent with habitat loss and degradation, temperate grasslands have been disproportionally affected by climate change relative to most other terrestrial biomes. Distributions of grassland birds often correlate with gradients in climate, but few researchers have explored the consequences of weather on the demography of grassland birds inhabiting a range of grassland fragments. To do so, we modeled the effects of temperature and precipitation on nesting success rates of 12 grassland bird species inhabiting a range of grassland patches across North America (21,000 nests from 81 individual studies). Higher amounts of precipitation in the preceding year were associated with higher nesting success, but wetter conditions during the active breeding season reduced nesting success. Extremely cold or hot conditions during the early breeding season were associated with lower rates of nesting success. The direct and indirect influence of temperature and precipitation on nesting success was moderated by grassland patch size. The positive effects of precipitation in the preceding year on nesting success were strongest in relatively small grassland patches and had little effect in large patches. Conversely, warm temperatures reduced nesting success in small grassland patches but increased nesting success in large patches. Mechanisms underlying these differences may be patch‐size‐induced variation in microclimates and predator activity. Although the exact cause is unclear, large grassland patches, the most common metric of grassland conservation, appears to moderate the effects of weather on grassland‐bird demography and could be an effective component of climate‐change adaptation. 相似文献
339.
Though managing vulnerabilities posed by climate change calls for effective strategies and measures, its challenges have hitherto not been fully understood. In Sweden, municipalities have recently started incorporating vulnerability management into their political and administrative agendas. This study discusses such experiences and explores how institutional determinants may influence adaptive capacity within a local case study area, to illustrate emerging challenges and opportunities for Swedish municipalities in managing climate vulnerabilities. Specifically, formal institutional structure and the use of knowledge are analysed, concluding that vulnerability management often is focused on technical and reactive fixes, due to limited co-operation between local sector organisations, lack of local co-ordination, and an absence of methods and traditions to build institutional knowledge. Even so, opportunities, such as a high capacity to examine risks to technical systems and important establishments which in turn facilitates protection of technical infrastructure exposed to climate variability and change, also exist. 相似文献
340.
Abstract Many of Canada's ex-urban and rural areas face a daunting array of sustainability challenges. In developing effective sustainability strategies, these areas must rely heavily upon local resources and capacities and existing social capital. Part of the solution for these areas may lie in multi-stakeholder collaborative approaches built on sustainability principles and strategies. These include the engagement and mobilization of civil society networks; the cultivation of strategic partnerships among key stakeholders in civil society, the private sector and government; and long-term local programmes of research, education and advocacy that are supportive of sustainability. This article describes and analyses a Canadian case study—Dufferin County, part of the Headwaters Country region in southern Ontario—in which a multi-stakeholder, civil society based approach to fostering sustainability is currently unfolding. The ideological and theoretical underpinnings of the initiative are explored, key process-oriented and substantive challenges to the approach are analysed and action research strategies are discussed. 相似文献