成都青白江地区地下水三氮特殊脆弱性评价

Study on Special Vulnerability of Three Nitrogen in Qing Baijiang,Cheng du

根据青白江地区的具体状况,分析青白江地区地下水三氮近30年分布变化特征。基于DRASTIC模型,综合考虑了自然因素和人为因素,选取地下水埋深(D)、降雨入渗补给系数(C)、含水层富水性(A)、地下水径流条件(R)、地下水三氮污染现状(N)、施氮肥量(F)、人口分布(P)及工业区排污(I)、建立了"三氮"特殊脆弱性评价指标体系。运用基于熵权法的叠置指数法,结合GIS技术对青白江区三氮特殊脆弱性进行了评价,结果表明脆弱性高区~极高区分布于以大弯镇川化工业片区和龙虎镇机械工业区为核心的周边区域,符合实际。

According to the specific conditions of Qingbaijiang region, this paper analyzed the distribution variation characteristic of groundwater three nitrogen in Qingbaijiang region during the past 30 years, based on DRASTIC model, and comprehensive considers the natural and man- made factors, selected groundwater depth( D), infiltration coefficient of precipitation( C), water yield property of aquifer( A), groundwater runoff conditions( R), three nitrogen pollution situation of groundwater( N), the application amount of nitrogen fertilizer( F), population distribution( P), industrial discharge capacity( I), established the 'three nitrogen' special vulnerability evaluation index system used the superimposed index evaluation method which was based on Analytic Hierachy Process, combined with GIS technology to evaluate the special vulnerability of three nitrogen in Qingbaijiang district. The results showed that high- extremely high vulnerability area was located in the Dawan town industrial area and Longhu town machinery industry area and its vicinity, which conformed to the reality.