江汉-洞庭平原浅层地下水防污性能评价

Assessment of Antipollution Capacity of Shallow Groundwater in Jianghan-Dongting Plain

为了解江汉-洞庭平原浅层地下水防污性能,在系统分析区域自然地理和水文地质条件的基础上,运用传统的DRASTIC评价模型,选取地下水埋深(D)、含水层净补给量(R)、含水层岩性(A)、土壤介质类型(S)、地形坡度(T)、包气带岩性(I)以及含水层水力传导系数(C)7个参数作为评价指标,根据所有污染物权重值确定各指标权重,建立了江汉-洞庭平原浅层地下水防污性能评价体系,并运用MAPGIS软件中的空间分析及制图功能对研究区进行了防污性能评价分区。结果表明:江汉-洞庭平原浅层地下水防污性能等级主要为中等,分布面积占总面积的66.52%,其次是防污性能等级较差,分布面积占总面积的30.32%,防污性能差和较好分别占总面积的3.08%和0.09%,评价结果可为区域地下水保护及工业布局提供理论支撑。

In order to understand the shallow groundwater antipollution of Jianghan-Dongting Plain,based on the systematic analysis of the natural geography and hydro geological conditions and DRASTIC model,seven evaluating indicators such as the groundwater depth(D),net recharge(R),aquifer media(A),soil media(S),topography(T),impact of the vadose zone media(I)and conductivity(C)are selected as evaluation indexes.According to all the pollutant weight value,the weight of each index is determined to establish an evaluation system for the anti-pollution performance of the shallow groundwater in the Jianghan-Dongting Plain.Powerful spatial analysis and mapping function of MapGIS is used to evaluate and partition the groundwater antipollution capacity in this study area.The result showed that the shallow groundwater had middling groundwater antipollution capacity in Jianghan-Dongting Plain,and the distribution area accounts for 66.52%of the total area,followed by the inferior grade of antipollution capacity.The distribution area accounts for 30.32%of the total area;the poor and good antipollution capacity account for 3.08%and 0.09%of the total area respectively,which can be a theoretical support for industrial layout and groundwater resources protection of this area.