基于GIS与DRASTIC模型的苏北黄泛平原典型区域地下水脆弱性评价

Groundwater vulnerability assessment in typical areas of the Yellow River floodplain in northern Jiangsu based on GIS and DRASTIC model

苏北黄泛平原地势平坦,浅部地层结构松散,地下水易受地表环境影响。为此,本文以南部的淮安市区为研究对象,选取影响研究区地下水脆弱性的7个主要指标,建立DRASTC脆弱性评价模型,利用GIS软件的空间分析功能,绘制出各指标分级图,而后进行各指标的加权叠加分析,得到脆弱性评价综合指数。评价结果表明区内地下水整体较脆弱,以苏北灌溉总渠为界,以北区域多为地下水脆弱性较高分区,总渠以南的洪泽区、施河-马甸-朱桥-博里一带为脆弱性中等分区。评价结果可为地下水污染防治、国土空间规划等工作提供科学的基础支持。

North Jiangsu Yellow River flood plain has flat terrain,loose structure in shallow strata,and groundwater is easily affected by surface environment.This paper takes Huai'an urban area in the south as the research object,selects seven main indicators that affect the groundwater vulnerability in the study area,establishes the DRASTC vulnerability assessment model,uses the spatial analysis function of GIS software to draw theclassification map of each indicator,and then carries out the weighted superposition analysis of each indicator to obtain the comprehensive vulnerability assessment index.The evaluation results show that the groundwater is relatively fragile as a whole,with the main irrigation canal in northern Jiangsu as the boundary,the northern region is mostly a high groundwater vulnerability zone,and the Hongze area and Shihe-Madian-Zhuqiao-Boli area in the south of the main canal are medium groundwater vulnerability zones.The evaluation results can provide scientific basic support for the prevention and cure of groundwater pollution、land space planning and other works.