河南商丘市规划中心城区浅层地下水防污性能评价

在分析商丘市规划中心城区自然地理及水文地质条件的基础上,基于DRASTIC评价方法,本文选取地下水位埋深、含水层岩性、土壤类型、地形坡度、包气带介质类型和含水层富水性6项指标作为评价因子,建立优化改进的评价模型—DASTIY模型,运用层次分析法(AHP)确定权重,并借助MapGIS进行研究区浅层地下水防污性能评价和分区。结果表明,商丘市规划中心城区浅层地下水防污性能整体为差,评价结果可为地方政府制定地下水资源保护及产业布局提供决策依据。     

基于GIS的郑汴新区浅层地下水环境脆弱性评价研究

本文通过系统分析郑汴新区水文地质条件,采用DRASTIC法,选取地下水位埋深、净补给量、含水层介质类型、土壤介质类型、地形坡度、包气带介质类型和含水层渗透系数共七项影响因子对郑汴新区地下水脆弱性进行了评价。并借助于GIS技术强大的输入、空间分析及制图功能,绘制了地下水环境脆弱性评价分区图。结果表明,郑汴新区地下水最脆弱的地带位于黄河南岸的黄河滩地、背河洼地区,以及中牟—开封南黄河冲积平原区,符合实际情况。地下水环境脆弱性评价图为城市规划、地下水资源开发利用及保护提供水文地质方面的依据。     

DRASTIC模型在贵州省毕节地段浅层地下水脆弱性评价中的应用

为了实现贵州省毕节地段地下水系统脆弱性评价的直观展示,选取含水层埋深、含水层补给、含水层介质类型、土壤介质类型、坡度、包气带厚度和渗透系数七项评价因子,采用DRASTIC模型建立了地下水系统脆弱性评价模型,通过模糊层次分析法(FAHP)确定了评价因子的权重,并基于ArcGIS软件对毕节地段地下水资源的各项数据指标进行了矢量化,实现了毕节地段地下水脆弱性等级划分的直观性分布图。评价结果表明,该区域地下水脆弱性较高且分布不均。     

基于DRASTIC指标体系法的平潭岛地下水防污性评价

地下水防污性能评价是地下水开发利用保护的重要组成部分,针对平潭岛地质背景和水文地质条件,利用DRASTIC评价方法,选取地下水位埋深、净补给量、含水层介质类型、土壤介质类型、地形坡度、包气带介质类型以及含水层渗透系数7个参数为评价指标,对该地区的地下水防污性能进行评价,将平潭岛地下水的防污性能分为防污性能高、较高、中等和较低4个等级,对平潭岛开发、建设,利用、保护地下水和土地利用、环境保护及城市规划等政策措施具有较重要的参考指导作用。     

DRASTIC在某地下水水源地脆弱性评价中的应用

为了了解某地下水备用水源地取水含水层的地下水脆弱性,首先根据资料收集和实地调查来确定水源地的含水层介质、上层土壤介质、包气带介质、含水层埋深和坡度,之后通过地下水数值模型反演出净补给量和渗透系数,最后利用DRAS-TIC方法对某地下水备用水源地取水含水层的地下水脆弱性进行评价.结果表明,取水含水层的地下水脆弱性指数介于...     

北京顺怀密地区地下水脆弱性评价

地下水饮用水源地的保护重在防治,地下水脆弱性评估意义重大.基于DRASTIC模型,运用层次分析法,结合GIS技术对北京市顺怀密研究区潜层地下水进行本质脆弱性评价与分区.结果表明,北京顺怀密研究区地下水脆弱性普遍较高,脆弱性相对较低和低区仅占研究区总面积的10.38％.此外,通过指标敏感度分析探讨了影响研究区本质脆弱性的主要因素,为特殊脆弱性评价体系的建立提供科学方向.     

基于GIS的黄水河流域地下水脆弱性评价研究

从影响地下水脆弱性的因素出发,结合国内外已有的地下水脆弱性影响因素、评价指标和评价标准,根据研究区的具体情况和可获得资料,确定了北方滨海地区地下水脆弱性的影响因素,建立了地下水脆弱性评价DRAMTICH指标体系和评价标准。以黄水河流域为例,进行了地下水脆弱性评价和编图,为当地今后制订地下水资源保护与管理、土地利用及城市规划等政策措施提供决策依据。该方法同样适用于其它类似地区的地下水脆弱性评价。     

VLDA模型及其在潜水脆弱性评价中的应用——以新疆焉耆县平原区为例

在地下水脆弱性评价的GOD法和DRASTIC模型的基础上,提出了VLDA模型,其中V为包气带岩性(1ithology of vadose zone)、L为土地利用方式(pattern of land use)、D为地下水埋深(groundwater depth)、A为含水层特征(aquifer characterist...     

基于层次分析法的DRASTIC模糊评价方法探讨——以云南曲靖盆地为例

在分析DRASTIC方法的基础上,结合前人研究成果,运用层次分析法构建了二层评价指标体系,并结合多层次模糊评价理论,建立了基于层次分析的DRASTIC二层模糊评价模型,并将该模型应用到曲靖盆地地下水脆弱性评价中。结果表明,该模型评价灵敏度高,更能反映地下水脆弱性的空间连续性,且该模型计算方法较简便,进一步丰富了地下水脆弱性的评价方法。     

基于熵权的集对分析方法在地下水脆弱性评价中的应用

针对传统集对分析在评价地下水脆弱性时认为各指标权重相同的缺点,以DRASTIC模型指标体系作为基础,将熵值理论与集对分析相结合,在集对分析中使用熵值法确定权重系数,对地下水脆弱性进行了评价,实现了特性权重随样本数据的动态变化。应用实例表明,该方法评价地下水脆弱性能够充分反映样本数据本身对指标权重的影响,评价结果更加客观、可靠。     

A GIS-based DRASTIC model for assessing aquifer vulnerability in Kakamigahara Heights, Gifu Prefecture, central Japan

Vulnerability assessment to delineate areas that are more susceptible to contamination from anthropogenic sources has become an important element for sensible resource management and land use planning. This contribution aims at estimating aquifer vulnerability by applying the DRASTIC model as well as utilizing sensitivity analyses to evaluate the relative importance of the model parameters for aquifer vulnerability in Kakamigahara Heights, Gifu Prefecture central Japan. An additional objective is to demonstrate the combined use of the DRASTIC and geographical information system (GIS) as an effective method for groundwater pollution risk assessment. The DRASTIC model uses seven environmental parameters (Depth to water, net Recharge, Aquifer media, Soil media, Topography, Impact of vadose zone, and hydraulic Conductivity) to characterize the hydrogeological setting and evaluate aquifer vulnerability. The western part of the Kakamigahara aquifer was dominated by "High" vulnerability classes while the eastern part was characterized by "Moderate" vulnerability classes. The elevated north-eastern part of the study area displayed "Low" aquifer vulnerability. The integrated vulnerability map shows the high risk imposed on the eastern part of the Kakamigahara aquifer due to the high pollution potential of intensive vegetable cultivation. The more vulnerable western part of the aquifer is, however, under a lower contamination risk. In Kakamigahara Heights, land use seems to be a better predictor of groundwater contamination by nitrate. Net recharge parameter inflicted the largest impact on the intrinsic vulnerability of the aquifer followed by soil media, topography, vadose zone media, and hydraulic conductivity. Sensitivity analyses indicated that the removal of net recharge, soil media and topography causes large variation in vulnerability index. Moreover, net recharge and hydraulic conductivity were found to be more effective in assessing aquifer vulnerability than assumed by the DRASTIC model. The GIS technique has provided efficient environment for analyses and high capabilities of handling large spatial data.     

Application of DRASTIC and extension theory in the groundwater vulnerability evaluation

Groundwater vulnerability assessment plays a vital role in the utilization and protection of groundwater resources. DRASTIC is one of the most widely used models for groundwater vulnerability assessment. However, the DRASTIC model should be modified based on the local hydrogeological conditions in order to get a relatively accurate result. In this study, Baotou, China was chosen as a case study. The groundwater vulnerability was assessed using DRASTIC at first, but the evaluation results were not consistent with the groundwater quality. So the DRASTIC model was modified based on extension theory and analytic hierarchy process (AHP) method. The extension theory could be used to divide the groundwater vulnerability grades in the DRASTIC model. It is a new attempt to use extension theory and DRASTIC in the assessment of groundwater vulnerability, and the research results show that this method is better for assessing groundwater vulnerability.     

A statistical and geographical information system analysis for groundwater intrinsic vulnerability: a validated case study from Sfax–Agareb,Tunisia

The groundwater vulnerability to the pollution assessment was considered as an efficient tool to limit and to control its quantitative and qualitative degradation risks. The DRASTIC high, moderate and low groundwater vulnerability zones of the Sfax–Agareb basin (Tunisia) cover about 10, 29 and 61% of the study area, respectively. The validation of the DRASTIC vulnerability map was undertaken through comparison of areas of high nitrate concentration and their relative vulnerability index. The DRASTIC vulnerability map illustrates a good rate of coincidence between the nitrate concentration ranges and the various vulnerability classes as recognized by statistical analysis. The reliability of the final vulnerability map has been tested, showing a general positive trend relating the mean nitrate concentration in the wells to their relative vulnerability classes (R²=0.88). When correlating the 214 available groundwater nitrate concentrations to the DRASTIC index in these wells location, a significant positive correlation with Cor=0.55 was found.     

Enhanced vulnerability assessment in karst areas by combining mapping with modeling approaches

The objective of this work is to facilitate a sustainable regional planning of water resources in karst areas by providing a conceptual framework for an integrative vulnerability assessment. A combined mapping and modeling approach is proposed, taking into account both spatial and temporal aspects of karst groundwater vulnerability. The conceptual framework comprises the delineation of recharge areas, vulnerability mapping, numerical flow and transport modeling and the integration of information into a combined vulnerability map and time series. The approach is illustrated at a field site in northwest Switzerland (Gempen plateau). The results show that the combination of vulnerability mapping and numerical modeling allows the vulnerability distribution, both in the recharge and discharge areas, to be identified, and at the same time, the time dependence of karst groundwater vulnerability to be assessed. The combined vulnerability map and time series provide a quantitative basis for drinking water management and for regional planning.     

Quantitative assessment of groundwater vulnerability using index system and transport simulation, Huangshuihe catchment, China

Groundwater vulnerability assessment has been an increasingly important environment management tool. The existing vulnerability assessment approaches are mostly index systems which have significant disadvantages. There need to be some quantitative studies on vulnerability indicators based on objective physical process study. In this study, we tried to do vulnerability assessment in Huangshuihe catchment in Shandong province of China using both contaminant transport simulations and index system approach. Transit time of 75% of hypothetical injected contaminant concentration was considered as the vulnerability indicator. First, we collected the field data of the Huangshuihe catchment and the catchment was divided into 34 sub areas that can each be treated as a transport sub model. Next, we constructed a Hydrus1D transport model of Huangshuihe catchment. Different sub areas had different input values. Thirdly, we used Monte-Carlo simulation to improve the collected data and did vulnerability assessment using the statistics of the contaminant transit time as a vulnerability indicator. Finally, to compare with the assessment result by transport simulation, we applied two index systems to Huangshuihe catchment. The first was DRASTIC system, and the other was a system we tentatively constructed examining the relationships between the transit time and the input parameters by simply changing the input values. The result of comparisons between the two index systems and transport simulation approach suggested partial validation to DRASTIC, and the construction of the new tentative index system was an attempt of building up index approaches based on physical process simulation.     

基于人工神经网络的水质污染综合评价方法

针对地下水水质污染综合评价工作的需要，本文提出基于B－P算法的人工神经网络模型，并用该模型对某地的水质污染作了综合评价。评价结果表明，该方法简便可靠，预测精度高，具有通用性和客观性。