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81.
本文应用灾害系统基本单元理论,以湖南省农业自然灾害为例,在地理信息系统支持下,将湖南省农业自然灾害系统划分为32524个基本单元。进而,以民政部1978~1993年农业灾情统计数据为标准,通过多因子逐步回归的方法,建立了反映湖南省多年平均状况的五种主要农业灾害灾情模型。最后,以灾害基本单元为最小空间分异单位,对综合农业灾情分异规律进行了探讨,并首次提出了基于自然单元的湖南省综合农业灾情的分异规律首先是受地势控制的东西分异的主要结论。 相似文献
82.
ENVIRONMENTAL AUDITING: A Synoptic Approach for Assessing Cumulative Impacts to Wetlands 总被引:1,自引:0,他引:1
/ The US Environmental Protection Agency's Wetlands ResearchProgram has developed the synoptic approach as a proposed method forassessing cumulative impacts to wetlands by providing both a general and acomprehensive view of the environment. It can also be applied more broadly toregional prioritization of environmental issues. The synoptic approach is aframework for making comparisons between landscape subunits, such aswatersheds, ecoregions, or counties, thereby allowing cumulative impacts tobe considered in management decisions. Because there is a lack of tools thatcan be used to address cumulative impacts within regulatory constraints, thesynoptic approach was designed as a method that could make use of availableinformation and best professional judgement. Thus, the approach is acompromise between the need for rigorous results and the need for timelyinformation. It is appropriate for decision making when quantitative,accurate information is not available; the cost of improving existinginformation or obtaining better information is high; the cost of a wronganswer is low; there is a high demand for the information; and the situationcalls for setting priorities between multiple decisions versus optimizing fora single decision. The synoptic approach should be useful for resourcemanagers because an assessment is timely; it can be completed within one totwo years at relatively low cost, tested, and improved over time. Anassessment can also be customized to specific needs, and the results arepresented in mapped format. However, the utility of a synoptic assessmentdepends on how well knowledge of the environment is incorporated into theassessment, relevant to particular management questions.KEY WORDS: Cumulative impact assessment; Landscape ecology; Regionalprioritization 相似文献
83.
以区域经济学为基础,灾害学为主导,应用层次分析原理,分析了山西省自然灾害对区域经济发展的影响,评价了不同区域的灾害严重程度及主要灾种,将全省划分为五大灾害经济区,为区域生产力布局提供了一些科学理论依据. 相似文献
84.
近五年中国自然灾害空间分布格局及其月动态变化研究 总被引:5,自引:7,他引:5
作者根据《中国减灾》所载1990~1994年月灾情记录,经统一编码和标准化处理,建立了以行政县为基本单元的数据库。进而对近五年来中国自然灾害空间分布及其月动态变化进行分析,并与1949~1990年中国自然灾害的平均状况进行对比。 相似文献
85.
流域性洪涝及其指标研究 总被引:5,自引:0,他引:5
本文讨论了区域洪涝指标,认为区域洪涝指标应反映出不同洪涝面积和不同洪涝等级对区域洪涝的影响程度,基于这一思想,提出了一个区域洪涝指标计算公式。为了使区域洪涝研究更为具体和可比,本文在分析区域洪涝指标的基础上,提出了流域性洪涝的概念,并以《中国近五年百旱涝分布图集》为基础,建立了淮河流域500年流性洪涝指标序列及其等级。 相似文献
86.
Recent attention has focused on resource management initiatives at the watershed scale with emphasis on collaborative, locally driven, and decentralized institutional arrangements. Existing literature on limited selections of well-established watershed-based organizations has provided valuable insights. The current research extends this focus by including a broad survey of watershed organizations from across the United States as a means to estimate a national portrait. Organizational characteristics include year of formation, membership size and composition, budget, guiding principles, and mechanisms of decision-making. These characteristics and the issue concerns of organizations are expected to vary with respect to location. Because this research focuses on organizations that are place based and stakeholder driven, the forces driving them are expected to differ across regions of the country. On this basis of location, we suggest basic elements for a regional assessment of watershed organizations to channel future research and to better approximate the organizational dynamics, issue concerns, and information needs unique to organizations across the country. At the broadest level, the identification of regional patterns or organizational similarities may facilitate the linkage among organizations to coordinate their actions at the much broader river basin or ecosystem scale. 相似文献
87.
Lance R. Williams Christopher M. Taylor Melvin L. Warren Jr. J. Alan Clingenpeel 《Environmental management》2002,29(1):76-87
Using Basin Area Stream Survey (BASS) data from the United States Forest Service, we evaluated how timber harvesting influenced
patterns of variation in physical stream features and regional fish and macroinvertebrate assemblages. Data were collected
for three years (1990–1992) from six hydrologically variable streams in the Ouachita Mountains, Arkansas, USA that were paired
by management regime within three drainage basins. Specifically, we used multivariate techniques to partition variability
in assemblage structure (taxonomic and trophic) that could be explained by timber harvesting, drainage basin differences,
year-to-year variability, and their shared variance components. Most of the variation in fish assemblages was explained by
drainage basin differences, and both basin and year-of-sampling influenced macroinvertebrate assemblages. All three factors
modeled, including interactions between drainage basins and timber harvesting, influenced variability in physical stream features.
Interactions between timber harvesting and drainage basins indicated that differences in physical stream features were important
in determining the effects of logging within a basin. The lack of a logging effect on the biota contradicts predictions for
these small, hydrologically variable streams. We believe this pattern is related to the large scale of this study and the
high levels of natural variability in the streams. Alternatively, there may be time-specific effects we were unable to detect
with our sampling design and analyses. 相似文献
88.
89.
从风险物质数量、风险诱发因素及风险防控能力角度出发,采用加权评分法,结合周边环境敏感受体情况,对沈阳市某化工园现状做环境风险评估。结果表明:JHYSD和XJHX的区域环境风险值贡献最大,分别为3.08和2.59,约占园区内总风险值的41.2%;该化工园综合环境风险值为13.57,构成该综合风险值的各分项大小不同,其中,RIS_(危险废物)分项环境风险最大,贡献率达到28.89%,其次为RIS_(大气),贡献率达27.34%,其余三者顺序为RIS_(化学品)RIS_水RIS_(累积)。 相似文献
90.
上海市浦东新区作为承接国家自由贸易区的先行试点地区,近年来吸引大批国内外企业入驻,同时经济发展与环境友好型社会矛盾依然突出。本文以2014年-2018年来浦东新区区域噪音与交通噪数据为依据,分析本地区声环境状况,结果表明声环境质量有所下降,一类功能区及交通噪音需进一步加强治理。通过源头屏蔽,大力发展张江、周浦、滴水湖等科技园区建设,阻断企业对居民区的噪声影响等措施,进而提升和改善浦东新区声环境质量状况。 相似文献