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水环境质量现状综合评价方法研究 总被引：3，自引：1，他引：3
通过实例，研究了水环境质量现状综合评价四种方法（综合指数祛、模糊数学综合评判法、灰色聚类评价法、数理统计法）的原理及特点。根据实际评价成果的对比，重点探讨了各评价方法在水环境质量价中的适用条件。 相似文献
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蒋辉 《水文地质工程地质》2004,31(3):46-50
本文用综合指数法、模糊数学法、类色聚类法等方法,对博爱县平原区地下水环境质量进行了综合评价,尤其是用后二种数字化评价方法,划分地下水环境质量等级,效果较好。 相似文献
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地下水环境质量评价的神经网络研究 总被引：7，自引：0，他引：7
基于模糊综合评判法和灰色聚类法的不足,应用神经网络理论与方法建立了地下水环境质量评价B-P网络模型,并用该模型对某地区的地下水环境质量作了评价。结果表明,该方法运用简便、精确可靠、可判性强。 相似文献
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根据邯郸市2012年地下水环境监测成果,采用内梅罗综合指数法和单因子评价法对邯郸市浅层地下水进行分析评价。邯郸市西部山区浅层地下水水环境质量较好,内梅罗综合评价结果指标值为0.80和2.50之间,单因子比较法评价结果多为地下水Ⅲ类水;东部平原的浅层地下水水环境质量恶劣,内梅罗综合评价法评价结果多为较差和极差,单因子比较法评价结果多为Ⅳ、Ⅴ类水。 相似文献
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水环境质量评价中几种方法的对比 总被引：15，自引：0，他引：15
通过对目前水环境质量评价中使用的各方法进行分析,并以西安市水环境质量评价为例, 对模糊综合评价法和模糊信息分配法进行比较.结果表明,模糊信息分配法评价出的结果分辩率高,评价结果准确,更符合实际. 相似文献
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对水环境质量综合评价中应用的多目标决策-理想点法进行了分析,认为实际上水环境质量评价标准是区间概念而非点的概念,因而传统的多目标决策-理想点法把评价标准处理成理想点存在一定缺陷。为了克服这种缺陷,提出了一种多目标决策-理想区间法(MODMIIM)。介绍了MODMIIM的原理,给出了它的构成方法,并把它应用到水环境质量综合评价中。MODMIIM与PP模型和神经网络法相比,简单、有效;与多目标决策理想点法相比,具有更大的适用性。MODMIIM可广泛应用于各种环境质量综合评价中。 相似文献
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The influence of water conveyances on restoration of vegetation to the lower reaches of Tarim River 总被引：2，自引：1，他引：1
Because of long-term stream-flow cut off in the lower reaches of Tarim River, environmental degradation has become the most
severe and widespread environmental problem in Tarim River basin. Nine ecological water conveyances to the lower reaches of
Tarim River made ecological environment change a lot. 3S technology was used to monitor dynamic change of ecology. However,
remote sensing area index cannot analyze ecological restoration degree of Tarim River precisely because the time of each water
conveyance is short, the change of vegetation area is not obvious, and there exists visual interpretation error. In this paper,
remote monitoring datum of high temporal resolution and high spatial resolution were used to research the relationships between
normalized difference vegetation index (NDVI) and the groundwater depth, between NDVI and the surface vegetation coverage,
and between the groundwater depth and the surface vegetation coverage. The growth and restoration of the vegetation in different
periods were evaluated by investigative analysis of the change trend of NDVI. The conception of relative restoration degree
was proposed and the response of vegetation restoration to the water conveyance was evaluated. The evaluation result suggests
that: first, the response of vegetation to the water conveyance concentrates within 1,000 m of both riversides, and the range
of influence becomes smaller along the lower reaches of Tarim River. Second, influenced by the groundwater recharge, the vegetation
coverage shows decreasing trend with the increase of off-river distance. Third, the vegetation coverage shows decreasing trend
along the watercourse influenced by the water consumption. Finally, in spatial, original scattered meadow of low coverage
transforms to high coverage gradually in research region. Vegetation response to the water conveyance expands to both sides
with the watercourse being the axis, and expanding scale increases continuously. 相似文献
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The weight of interaction of mining activities: groundwater in environmental impact assessment using fuzzy analytical hierarchy process (FAHP) 总被引：2，自引：0，他引：2
Mining operations threaten the environment if the monitoring and controlling steps are not implemented completely. One of the important methods for control of the environmental situation in the mining district is the environmental impact assessment (EIA) method, which is performed by matrix calculations. In this method, the environmental problem is broken into several parts as the Impacting Factors that is evaluated their influences on Environmental Components by the mathematical calculations. For these calculations, the weight of each Impacting Factor must be evaluated by using comprehensive scenarios that are involved all the predicable environmental issues. Based on literature, it has not been organized a comprehensive scenario about “Interference with groundwater” as an Impacting Factor yet. By consideration of the importance degree of groundwater and its role in supply the drinking water resource, it is felt to demand for an organization a developed scenario in relation with groundwater pollution in mining district. Therefore, the main aim of this study is developing a new scenario to weight the “Interference with groundwater” in EIA matrix. For this purpose, the 8 criteria and 63 subcriteria are defined and their weights are determined using the Fuzzy Analytic Hierarchy Process. The proposed scenario can be successfully evaluated the weight of “Interference with groundwater” Impacting Factor more exactly than the former one, because it considers 8 criteria and 63 subcriteria instead of 2 criteria in the former scenario. Finally, the application of proposed scenario is illustrated by an imaginary ideal case study. Such studies can be used by mining engineers and planners to design an appropriate environmental plan for the mining districts. 相似文献
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以最新水资源评价成果为依据,阐述了山东省地下水资源状况、重要水源地的分布、开发利用潜力及地下水独特的优越性,强调了合理开发利用与保护地下水资源对山东省经济发展的重要性。认为地下水过量开采或开采程度过低,容易引起超采漏斗区、地面塌陷、沉降、裂缝、海水倒灌以及土壤盐渍化、渍涝等一系列生态环境问题,结合山东实际情况提出促进地下水利用良性循环的对策。 相似文献
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Jonathan A. Holmes 《Geochimica et cosmochimica acta》2008,72(12):2934-2945
The magnesium and strontium contents of fossil ostracod-shell calcite have been used extensively in the reconstruction of water composition and temperature in lakes and, to a lesser degree, in marginal-marine waters and in the deep ocean. Current instrumentation may allow single shells of these calcite microfossils to be analysed and most studies have taken advantage of this capability. However, there is now good evidence for large intra-sample variability in the trace-element content of ostracod shells, both in living populations and in fossil assemblages, and this has implications for any attempt to distinguish the low-frequency (∼decadal or longer) trends in water temperature and composition that are often the goals of palaeoenvironmental studies, from higher-frequency (seasonal or interannual) ‘noise’. In this study, the Mg and Sr contents of living and fossil populations of six species of marine, marginal-marine and shallow-marine ostracods from 11 sites are used to investigate sources of variability and to estimate critical sample sizes for stratigraphic studies. Results confirm that variability amongst individual samples is generally wide and cannot be attributed to instrumental error or sample handling alone. In some instances, variability can be explained by fluctuations in water composition and/or temperature, although this has to be evaluated in each case. Some evidence points to non-environmental control on variability in shell composition, perhaps connected to genetically-controlled differences in physiology that affected calcification, early diagenetic alteration, or the role of environmental factors other than temperature or water composition. However, further work is needed to verify this. In some stratigraphic studies, large numbers (>20) of individual shells would need to be analysed in order to detect low-frequency environmental changes with any degree of confidence, although fewer shells may often suffice. The critical sample size depends on the variability at each study site, which should ideally be evaluated using pilot studies. 相似文献
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城市环境问题已越来越多地困扰着城市的发展,而城市环境问题中最重要的又是水环境。文中简要阐述了四川某城市环境地质背景,对该城市地表水和地下水质量给予了评价,最后结合城市供水问题,对该市的水环境质量进行了综合评价并得出了合理的结论。 相似文献
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在野外调查和收集现有资料基础上,对下河泉水源地水文地质条件、泉水流量动态、水源地保证程度与可能的环境问题进行了分析,论证了建立下河泉水源地的可行性. 相似文献
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在评述河南省地热水资源的分布及其开发利用状况的基础上,依据评价标准对河南省地热水资源的开发利用程度进行了评价。基于各地的地热水资源开发利用程度,从开采总量控制、地热井规划布局、开发利用现状分区、资源利用优化配置、资源勘查规划及重点项目规划等五个方面对河南省地热水资源开发利用进行了科学系统规划,为充分发挥河南省地热水资源的最大效益并避免环境水文地质问题的发生奠定了基础。 相似文献