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401.
芦山地震震后次生滑坡灾害风险评价研究 总被引:2,自引:2,他引:0
以北京时间2013年4月20日8时02分四川省雅安市芦山县7.0级地震为例,对研究区进行震后次生滑坡灾害风险评价.研究在利用芦山地震受灾区航空影像对震后次生滑坡灾害隐患点解译的基础上,选择坡度、坡向、震后累计降雨量和危险植被指数4个评价因子,利用统计分级法对各因子进行敏感性分析,采用层次分析法(Analytic Hierarchy Process,AHP)对评价因子进行权重量化,最后综合运用GIS空间分析技术对芦山地震震后次生滑坡灾害进行风险评价,研究结果将研究区划分为次生滑坡灾害高危险区、中危险区和低危险区. 相似文献
402.
自然灾害脆弱性曲线研究进展 总被引:12,自引:2,他引:10
在全球变化与全球化背景下自然灾害风险逐年增大,灾害评估就成为风险防范的重要基础。灾害评估包括灾情估算与风险评估2个方面,而脆弱性分析是把灾害与风险研究紧密联系起来的重要桥梁。脆弱性曲线作为定量精确评估承灾体脆弱性的方法,近年来在多领域被广泛运用,成为灾情估算、风险定量分析以及风险地图编制的关键环节。从致灾因子角度综述脆弱性曲线的研究进展,重点阐述基于灾情数据、已有曲线、调查和模型的脆弱性曲线构建。研究表明脆弱性曲线构建由单曲线向多曲线库、单一参数向综合参数、单一方法向多领域综合应用发展,具有综合化和精细化的趋势。进一步开展多领域、多方法综合脆弱性曲线研究,对灾损快速评估及风险评价,防灾减灾具有重要意义。 相似文献
403.
面向灾害风险评估的热带气旋路径及强度随机模拟综述 总被引:1,自引:0,他引:1
历史热带气旋记录时间序列较短空间差异大,热带气旋灾害风险评估经常面临样本不足,特别是超强台风及巨灾记录历史样本的问题,从而导致传统概率统计方法失效。过去20多年来,逐渐发展出一套完整的方法体系进行热带气旋路径及强度随机模拟,其特点是充分利用历史总体样本信息,生成大量符合历史样本特征的热带气旋路径及强度随机事件样本集,从而有效地解决了局地历史样本不足的问题。在回顾热带气旋的年频次、季节分布、路径分布、强度及影响范围时空规律研究进展基础上,系统综述了用于热带气旋路径及随机模拟的起始点模型、行进模型、终止点模型、洋面强度模型、陆地衰减模型及结果检验方法等领域的进展及不足,然后对其在世界各地的应用进行了概述,并对未来研究改进方向及应用领域进行了展望。 相似文献
404.
405.
社会救援力量业务的经费保障对社会救援队伍的建设至关重要。基于社会救援力量业务的经费保障现状,研究了为什么要进行社会救援力量业务经费保障,剖析了社会救援力量经费保障的不同阶段(经费筹措管理、经费日常管理、经费支出管理及经费监督管理)遇到的风险问题,并有针对性地提出了社会救援力量业务的经费保障风险防控优化对策。研究表明,开展此项研究有助于进一步丰富社会救援力量业务的经费保障理论体系,也有助于社会救援力量的持续健康发展。 相似文献
406.
This paper presents an alternative framework to the approach currently embodied in the Kyoto Protocol for managing global climate change post-2012. The framework has two key provisions. The first is that each person in the world would be ‘allowed’ an equal amount of greenhouse gas (GHG) emissions. This is labeled the equity-first provision. The second provision focuses on incorporating risk concepts into the setting of GHG emission reductions. It is proposed that the global climate be managed as to avoid three categories of risks: (I) Substantial regional economic, political, and/or biological impacts; (II) Severe global economic, political, and/or biological impacts; and (III) Extinction of humans. Acceptable risk thresholds are suggested to be one-in-a-million, one-in-one-hundred-million, and one-in-ten-billion, respectively. This equity-first, risk-based framework overcomes many criticisms of the current Kyoto Protocol: it explicitly involves all countries on earth; it avoids several administrative issues that are anticipated to plague a global carbon emissions trading market; and it avoids several contentious issues associated with pegging carbon emission reductions to 1990 levels. Because the framework is risk-based and emissions are tied to population and not historic emission levels, the basic framework would not have to be frequently renegotiated, as will be needed for the Kyoto-style approach to take the world past that agreement's 2012 endpoint. 相似文献
407.
408.
Steven?CarrollEmail author Ashantha?Goonetilleke Les?Dawes 《Environmental Geology》2004,46(2):195-208
Current methods of establishing suitable locations for onsite wastewater treatment systems (OWTS) are inadequate, particularly in light of the numerous cases of onsite system failure and the resulting adverse consequences. The development of a soil suitability framework for assessing soil suitability for OWTS allows a more practical means of assessment. The use of multivariate statistical analysis techniques, including Principal Component Analysis (PCA) and multi-criteria decision aids of PROMETHEE and GAIA, enabled the identification of suitable soils for effluent renovation. The outcome of the multivariate analysis, together with soil permeability and drainage characteristics permitted the establishment of a framework for assessing soil suitability based on three main soil functions: (1) the ability of the soil to provide suitable effluent renovation, (2) the permeability of the soil, and (3) the soils drainage characteristics. The developed framework was subsequently applied to the research area, Gold Coast, Queensland, Australia, and the use of standard scoring functions were utilised to provide a scoring system to signify which soils were more suitable for effluent renovation processes. From the assessment, it was found that Chromosol and Kurosol soils provided the highest level of effluent renovation, closely followed by Ferrosol and Dermosol, Kandosol and Rudosol soil types. Tennosol and Podosol soil types were found to have a significantly lower suitability, with Hydrosol soils proving the least suitable for renovating effluent from OWTS. 相似文献
409.
410.
Ballast water sampling as a critical component of biological invasions risk management 总被引:8,自引:0,他引:8
The human mediated transfer of harmful organisms via shipping, specifically via ballast water transport, leading to the loss of biodiversity, alteration of ecosystems, negative impacts on human health and in some regions economic loss, has raised considerable attention especially in the last decade. Ballast water sampling is very important for biological invasions risk management. The complexity of ballast water sampling is a result of both the variety of organism diversity and behaviour, as well as ship design including availability of ballast water sampling points. Furthermore, ballast water sampling methodology is influenced by the objectives of the sampling study. In the course of research conducted in Slovenia, new sampling equipment for ships' ballast water was developed and tested. In this paper new ballast water sampling methods and equipment together with practical shipboard testing results are presented. 相似文献