中文摘要：

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（lithology 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 characteristics）。以新疆焉耆县平原区为例,在GIS平台上,利用VLDA模型评价该地区潜水的脆弱性,并与2009年9月潜水硝酸盐含量进行对比,结果表明：焉耆县平原区孔隙潜水脆弱性相对较高的区域面积占40.83%,主要分布在西北部地区（包括库尔勒市城市地下水水源地）和焉耆镇一带;潜水高脆弱性区与潜水硝酸盐含量高值区基本一致,说明应用VLDA模型开展地下水脆弱性评价具有可行性。为解决城市供水与地下水脆弱性这一对矛盾,应加强该地区地下水污染防治工作,并应坚持＂以预防为主,防、治结合＂的原则。

英文摘要：

Based on GOD method and DRASTIC model for groundwater vulnerability assessment,this paper proposes VLDA model for assessment of phreatic groundwater vulnerability,where V is the lithology of vadose zone,L is the pattern of land use,D is the groundwater depth,A is the aquifer characteristics.As an example,the paper assesses vulnerability of phreatic groundwater in Yanqi county of Xinjiang by using the VLDA model as the tool and GIS as the platform,and compares the vulnerability with nitrate content of the phreatic groundwater in September 2009.The results of assessment show that areas with relatively highly vulnerable pore phreatic groundwater takes up 40.83% of the total plain area of Yanqi county,including mainly the northwestern area（such as the groundwater wellfield of Korla city） and Yanqi township,and that phreatic groundwater areas with higher vulnerability are essentially coincident with the areas with higher nitrate content,which indicates the feasibility of using VLDA model to assess groundwater vulnerability.To address the apparent contradictions between urban water supply and groundwater vulnerability,it is necessary to strengthen the prevention and the control of groundwater pollution in the above mentioned areas,and the principle of ＂putting the prevention first and combining the prevention with the control＂ should be adhered to in taking actions.