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721.
Jeffrey L. Arthur Robert G. Haight Claire A. Montgomery Stephen Polasky 《Environmental Modeling and Assessment》2002,7(2):81-89
Two approaches to formulating the reserve site selection problem when species occurrence data is probabilistic were solved for terrestrial vertebrates in a small set of potential reserve sites in Oregon. The expected coverage approach, which maximizes the sum of the occurrence probabilities, yielded solutions that covered more species on average in Monte Carlo simulations than the threshold approach, which maximizes the number of species for which the occurrence probability exceeds some threshold. 相似文献
722.
723.
Combating desertification requires the involvement of many people ranging from communities who experience the effects on a
daily basis and scientists attempting to understand the biophysical and socio-economic causes and consequences of desertification,
to developers and policy makers on all levels. In many instances, however, the understanding, approaches and actions of these
different groups contradict rather than support one another. Over the period 2000 to 2002, a conference process undertaken
in southern Africa brought together communities, scientists, and development workers to test the concept that they could connect
and work together to combat desertification, given an appropriate framework. The conference was a success, and communities,
scientists and developers did exchange experience, knowledge and information. Many lessons were learned, although some pitfalls
were experienced. Time, funding, enhanced communication, and good will are the primary ingredients for ensuring that different
sectors complement one another in their efforts to combat desertification. 相似文献
724.
Hoenicke R Davis JA Gunther A Mumley TE Abu-Saba K Taberski K 《Environmental monitoring and assessment》2003,81(1-3):15-25
The San Francisco Estuary Regional Monitoring Program (RMP) for Trace Substances is an innovative partnership among a regulatory agency, more than 70 regulated entities, and an independent scientific organization. The institutional arrangement behind the RMP has made the regulatory system increasingly responsive to emerging management needs, particularly with regard to the development of total maximum daily loads and ecosystem impairment assessment. Through multi-agency partnerships within and outside the RMP institutional structure, major information gaps for several pollutants of concern have been narrowed, resulting in a successful consensus-based regulatory approach to managing copper and nickel mass inputs into the Estuary. Short-term research efforts, based upon monitoring results, helped identify the most cost-effective control and remediation options for various bioaccumulative substances. Additionally, adaptive changes to the monitoring program documented the existence of widespread aquatic toxicity in the Estuary that is apparently due to pesticide runoff from agricultural and urban areas. One of the most important contributions of this collaborative monitoring program is the deliberate and systematic adjustment of management and research questions that serve to influence and add relevance to the overall research agenda related to San Francisco Estuary ecosystem assessment. 相似文献
725.
本文对内蒙古自治区和包头市环境保护信息化发展条件、现实状况和不足作了分析;提出了制定“数字环保规划”、推广使用国家环境监理信息系统、建立黄河监测和监理信息系统和提高人员信息化素质等建议。 相似文献
726.
重庆市地质灾害风险评估信息系统 总被引:5,自引:0,他引:5
重庆市地质灾害类型多,分布广,危害大,传统的预测预报及评估方法已显落后,迫切需要构建一套能快速、准确评价该区地质灾害危险性、易损性的具有模块化、网络化的风险评价系统.在Windows环境下,以GIS系列工具软件为基础平台,采用数据库管理技术对数据进行采集、存储、管理、分析、计算和图形显示,利用计算机语言的编程功能,开发了重庆市地质灾害评估信息系统,使有关决策部门能够方便地对系统进行查询和分析,获取所需要的地质灾害评估结果,为有关部门的灾害预测预报和提出有效、科学的防灾、减灾和救灾措施提供依据. 相似文献
727.
重大危险源安全监管信息系统的开发研究 总被引:16,自引:20,他引:16
从重大危险源安全监管的现实需要出发,研究了重大危险源企业安全管理与政府安全监管信息系统的总体框架及其软、硬件结构,并开发出了重大危险源安全监管信息系统。该系统主要包括重大危险源辨识、安全评价与分级、远程实时监控、GIS电子地图、GPS定位、应急救援预案及指挥、选址与安全规划等子系统,为我国建立全国重大危险源监控信息网络系统提供了一个标准的、先进的信息化平台。该信息系统已经在江苏、山东、河北等省重大危险源监控网络系统建设试点中得到了广泛应用,提高了重大危险源监管水平,取得了良好的效果。 相似文献
728.
基于火灾统计灾情数据的城市火灾风险分析 总被引:7,自引:5,他引:7
进行参数估计简单假设观察数据服从特点分布,由于条件变化,实际计算过程中往往出现不同状况下获得的数据服从不同分布的情况,从而存在假设与实际情况差异.本文介绍了信息扩散原理及其计算过程,信息扩散过程可以将一个孤立的观测值变成一个模糊集.利用上述特性,结合城市火灾统计数据给出了城市火灾风险的评估过程,确定了某市发生火灾后的损失率及其超越概率,为城市消防规划提供了技术参考. 相似文献
729.
水中触电危险性浅析及对策研究 总被引:1,自引:0,他引:1
通过典型事故案例分析,针对具有水中触电危险场所及极度潮湿场所触电事故多发、隐患严重以及相关技术标准不健全的现状,对水中触电危险性及预防这一课题进行了初步分析与研究,通过实验,初步了解了水的导电特性以及在带电的水中电压、电位差分布状况;对人体在带电的水中受到电击时的电压分布,触电电流走向进行了分析。笔者提出多项改进措施,在接地、接零系统中采用大幅度降低保护零线阻抗和重复接地电阻值以及加强等电位措施,正确使用漏电开关及安全隔离变压器等方法。上述改进措施具有一定的实用价值和可操作性,从而解决具有水中触电危险场所及极度潮湿场所的电气安全问题。 相似文献
730.
David C. Garen Daniel S. Moore 《Journal of the American Water Resources Association》2005,41(2):377-388
ABSTRACT: Although the curve number method of the Natural Resources Conservation Service has been used as the foundation of the hydrology algorithms in many nonpoint source water quality models, there are significant problematic issues with the way it has been implemented and interpreted that are not generally recognized. This usage is based on misconceptions about the meaning of the runoff value that the method computes, which is a likely fundamental cause of uncertainty in subsequent erosion and pollutant loading predictions dependent on this value. As a result, there are some major limitations on the conclusions and decisions about the effects of management practices on water quality that can be supported with current nonpoint source water quality models. They also cannot supply the detailed quantitative and spatial information needed to address emerging issues. A key prerequisite for improving model predictions is to improve the hydrologic algorithms contained within them. The use of the curve number method is still appropriate for flood hydrograph engineering applications, but more physically based algorithms that simulate all streamflow generating processes are needed for nonpoint source water quality modeling. Spatially distributed hydrologic modeling has tremendous potential in achieving this goal. 相似文献