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121.
122.
GIS技术在环境影响评价中的应用 总被引:3,自引:0,他引:3
为了研究地理信息系统(GIS) 在环境影响评价中的应用,在介绍地理信息系统的组成、类型、功能和应用领域的基础上,分析了GIS 技术在环境影响评价中的优势.从项目环境影响评价(EIA) 的局限性出发,简述了目前EIA 的研究现状,同时概述了地理信息系统(GIS) 的功能和应用,重点讨论了环境影响评价领域中应用地理信息系统的现状、必要性及其展望. 相似文献
123.
以2000年和2004年的QuickBird卫星影像解译的徐径镇土地利用类型图为基础,对土地利用类型变化的幅度和土地利用类型之间转换的空间关系进行了研究,同时选取合适的景观格局指数对该区域的景观格局进行了分析。最后,给出结论和建议。 相似文献
124.
江西省主要城市空气质量预报研究 总被引:2,自引:0,他引:2
对建立江西省各主要城市的空气洁净指数及空气污染指数预报模式进行了探讨,并将试验期间预报结果和所属区域空气污染程度进行比较,结果表明,该模式用于各省各主要城市空气洁净指数及空气污染指数预报是可行的。 相似文献
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Robert B. Olshansky 《Environmental management》1996,20(1):11-23
The California Environmental Quality Act (CEQA) has evolved from a mini-NEPA, first enacted in 1970, into a procedural act
that affects the approval process of all large developments in California. In 1990, California local governments produced
over 1600 environmental impact reports and 30,000 initial studies under CEQA. Because of its widespread use, CEQA has periodically
drawn the attention of the state legislature, most recently in 1993, when over 60 CEQA reform bills were introduced. This
paper describes the CEQA process and evaluates its success at meeting its explicit and implicit goals. The research includes
a statewide survey of CEQA practice, sent to the planning departments of all 513 local governments in California in 1991.
Survey respondents agreed that CEQA helps in evaluating environmental impacts, reducing impacts, informing the public, and
coordinating public agency review. It is effective in reducing the environmental impacts of individual projects, but is not
as effective in improving environmental quality on an areawide scale. This research concludes that CEQA has led to positive
outcomes and is not as deeply flawed as many of its critics claim. Still, CEQA as currently designed may not be the optimal
vehicle for ensuring environmental quality. 相似文献
129.
The Finnish anthropogenic CH4 emissions in 1990 are estimated to be about 250 Gg, with an uncertainty range extending from 160 to 440 Gg. The most important sources are landfills and animal husbandry. The N2O emissions, which come mainly from agriculture and the nitric acid industry are about 20 Gg in 1990 (uncertainty range 10–30 Gg). The development of the emissions to the year 2010 is reviewed in two scenarios: the base and the reduction scenarios.According to the base scenario, the Finnish CH4 emissions will decrease in the near future. Emissions from landfills, energy production, and transportation will decrease because of already decided and partly realized volume and technical changes in these sectors. The average reduction potential of 50%, as assumed in the reduction scenario, is considered achievable.N2O emissions, on the other hand, are expected to increase as emissions from energy production and transportation will grow due to an increasing use of fluidized bed boilers and catalytic converters in cars. The average reduction potential of 50%, as assumed in the reduction scenario, is optimistic.Anthropogenic CH4 and N2O emissions presently cause about 30% of the direct radiative forcing due to Finnish anthropogenic greenhouse gas emissions. This share would be even larger if the indirect impacts of CH4 were included. The contribution of CH4 can be controlled due to its relatively short atmospheric lifetime and due to the existing emission reduction potential. Nitrous oxide has a long atmospheric lifetime and its emission control possiblities are limited consequently, the greenhouse impact of N2O seems to be increasing even if the emissions were limited somehow. 相似文献
130.
森林大火潜在危险和可燃物干旱度研究 总被引:3,自引:0,他引:3
介绍了森林大火潜在危险的可燃物干旱度指标研究,以及干旱度指数SDI的计算方法,同时对干旱度指数进行了划分确定,以便在森林大火预报中作参考使用。 相似文献