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91.
A process has been developed to select watersheds that are representative of terrestrial ecoregions and that are relatively undisturbed by human activity. Using an existing land classification system at two hierarchical levels of resolution, representative subsets (ecodistricts) of large-scale ecoregions were selected, on the basis of their physiographic, biological, and climatological attributes, to represent the ecoregions. This was achieved using a frequency distribution analysis of existing attribute data and choosing the ecodistrict most closely resembling the most common set of conditions for that ecoregion. Within each ecodistrict, river basins were selected through a best-judgement evaluation of land use, coupled with an assessment of the size and location of each river basin, in order to meet the condition of minimal human impact. Preliminary assessment of water quality data collected from six watersheds selected in this way suggests that the process is effective in targeting regional scale river basins exhibiting the desired characteristics.  相似文献   
92.
在全面介绍沈阳市环境污染责任保险推进情况的基础上,论述了沈阳市参加保险企业的确定原则、推进方法及配套政策措施,并结合当前沈阳市该险种推进过程中存在的问题,提出了选择适合的环境污染责任保险模式、加强环保部门与保险行业的合作、将环境污染责任险融入到环境管理工作中等建议及对策。  相似文献   
93.
A procedure is described for conducting floristic examinations of prospective sites of development in order to determine the presence of threatened and/or endangered plant species. The timed meander search procedure provides information to document the level of effort expended in the examination as well as to describe the floristic resources of the site. Tests of the procedure during the 1979 and 1980 field seasons have demonstrated its value both as a means of discovering threatened and endangered species on a site and as a means of documenting a low probability of occurrence of such species if not found during application of the procedure.  相似文献   
94.
This paper looks at the use and effectiveness of the Site of Special Scientific Interest designation in three counties in the East Midlands region of the Nature Conservancy Council, namely Nottinghamshire, Northamptonshire and Cambridgeshire. Using unpublished sources within the NCC an analysis is made of the SSSI system in practice since its inception in 1949. A number of findings relating to weaknesses in the designation and the operation of the designation system emerge. Each of these findings is discussed in turn with the presentation of the appropriate evidence from the county case studies.  相似文献   
95.
以经过城市垃圾场的某高速公路连接线项目及矿山选址与生态环境敏感区的大型水泥建设项目为例,剖析项目在选址方面的法律、法规相容性,这些项目或由于与某些政策不相符;或由于法规、政策、规划颁布的部门不同,会出现不包容现象,而项目选址从其它角度考虑又很难调整。作为评估机构在评估这类项目时,应充分利用信息优势,发挥专家特长,协调几者关系,帮助建设单位调整项目方案,提出环境影响减缓措施,科学公正地给出建设项目的评估意见,帮助审批部门把好关。  相似文献   
96.
为解决地震勘探无线传感网络节点数量大、定位的网络开销大的问题,本文提出了一种针对地震勘探传感器网络节点定位的方法,使得地震勘探传感器网络节点的定位过程充分依赖检波器的空间分布和相对位置一定这一特点大大简化。作者还利用MATLAB的GUI程序设计实现了该方法的可视化参数可调的动画仿真。通过该仿真论证了该定位方法的可行性。  相似文献   
97.
随着我国环境保护力度的不断加大,环境调查工作正在有序的开展,其中场地土壤、地下水污染是环境调查的重点,而科学的调查采样方法则是确保调查结果准确性、客观性的必然要求。有鉴于此,首先从污染场地特征分析、调查目标两个角度介绍了场地环境调查的准备工作,然后探讨了布点中的前期准备以及具体方法,最后围绕土壤样品以及地下水样品的采集与保存做了分析。  相似文献   
98.
自然灾害和人密切相关,这不仅表现在自然灾害施予的客体是人,人的伤亡和财产损失是自然灾害的标志,而且表现在自然灾害的发生受人类活动的强烈影响。地质勘探活动是人类改造自然获取财富的主要活动之一。它一方面遭受自然灾害的危害,另一方面存在诱发触发自然灾害的危险,自然灾害已成了地质勘探活动的巨大障碍。自然灾害特别是地质灾害(人工诱发触发地质灾害、地方病)和气象灾害的测、报、防、治、救措施和方法研究是地质勘探劳动保护的重要课题。  相似文献   
99.
The potential to capture carbon from industrial sources and dispose of it for the long-term, known as carbon capture and sequestration (CCS), is widely recognized as an important option to reduce atmospheric carbon dioxide emissions. Specifically, CCS has the potential to provide emissions cuts sufficient to stabilize greenhouse gas levels, while still allowing for the continued use of fossil fuels. In addition, CCS is both technologically-feasible and commercially viable compared with alternatives with the same emissions profile. Although the concept appears to be solid from a technical perspective, initial public perceptions of the technology are uncertain. Moreover, little attention has been paid to developing an understanding of the social and political institutional infrastructure necessary to implement CCS projects. In this paper we explore a particularly dicey issue--how to ensure adequate long-term monitoring and maintenance of the carbon sequestration sites. Bonding mechanisms have been suggested as a potential mechanism to reduce these problems (where bonding refers to financial instruments used to ensure regulatory or contractual commitments). Such mechanisms have been successfully applied in a number of settings (e.g., to ensure court appearances, completion of construction projects, and payment of taxes). The paper examines the use of bonding to address environmental problems and looks at its possible application to nascent CCS projects. We also present evidence on the use of bonding for other projects involving deep underground injection of materials for the purpose of long-term storage or disposal.  相似文献   
100.
三峡水库自 2 0 0 3年蓄水后 ,水对斜坡 (滑坡 )的软化作用和库岸再造大大改变了库区的工程地质条件 ,库区的地质灾害严重制约了库区移民迁镇工程 ,场地建筑安全评价显得尤为重要。笔者根据库区工程地质的特点 ,提出了场地建筑适宜性评价的指标体系 ,建立了场地建筑安全评价人工神经网络模型。通过对红石包滑坡进行各种工况下的稳定性评价 ,利用稳态坡形、坡角工程地质类比法对红石包进行库岸再造的预测 ,对三峡库区巴东县新城区红石包油库建筑进行安全评价。为库区移民迁镇工作提供科学依据。  相似文献   
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