淮河流域平原区浅层地下水硝酸盐特殊脆弱性评价

Study on specific vulnerability of nitrate in shallow groundwater in Huai River plain area

特殊脆弱性评价是地下水硝酸盐污染区域性防治的前提.结合淮河流域水文地质条件和硝酸盐污染特点,对传统地下水特殊脆弱性模型DRASTIC进行了改进,建立了基于地下水位埋深(D)、净补给量(R)、含水层富水性(A)、土壤介质(S)、包气带介质(I)、土地利用类型(L)、地下水开采量(E)为评价因子的DRASILE模型,采用经验值与实际硝酸盐浓度共同确定体系给分表,利用二层次的层次分析法确定各指标的权重,最终制定了淮河流域平原区浅层地下水硝酸盐特殊脆弱性评价图.为了检验结果的可靠性,在SPSS21.0用F统计量和皮尔森相关系数(ρ)分别进行指标选取和脆弱性分值准确性的检验,最终通过显著性检验且相关系数达到0.559.本研究为地下水特殊脆弱性评价提供了新思路.

Specific vulnerability assessment is the basis of regional control on nitrate pollution in groundwater.In order to improve the traditional groundwater vulnerability model（DRASTIC）,this study combined hydrogeological data with nitrate pollutant characteristics and built DRASILE model to assess the specific vulnerability of shallow groundwater nitrate in Huai River plain area,which involves depth to the water table（D）,net recharge（R）,water yield property of aquifer（A）,soil type（S）,impact of the vadose zone（I）,land use type（L）,groundwater exploitation（E）.The empirical value and the actual nitrate concentration were used to determine the rating scale and the weights of the indexes were determined by using the analytic hierarchy process of two levels.The specific vulnerability map of shallow groundwater nitrate in Huai River plain was created.Fstatistic andρwere used in SPSS21.0respectively totest the accuracy of the index and vulnerability values.The results are encouraging and this study provides a new train of thought for groundwater specific vulnerability assessment.