西安市地下水污染广义/狭义脆弱性对比研究

从"污染源排放→包气带输送→地下水污染"的系统出发,提出了地下水污染广义和狭义脆弱性的概念,并构建了相应的指标体系和评价方法;在广泛污染源调查和水文地质调查的基础上,在GIS支持下完成了地下水污染脆弱性分析试验.结果显示:纯水文地质条件的狭义脆弱性,各河道、漫滩阶地、一级阶地和老城人工填土区最为脆弱;考虑土地利用和污染源分布的广义脆弱性评价,西安市建城区和北郊污灌区敏感最高.从而得出,狭义脆弱性适合人类活动差异较小的较大区域,而广义脆弱性适合人类活动差异较大的城市区域,两者有其适用的条件和范围.

A Comparative Study of Groundwater Pollution Narrow/General Vulnerability in Xi'an

Based on the system of "pollution source drainage-vadose zone transmission-groundwater pollution",this paper has put forward the concept of narrow and general groundwater vulnerability and constructed the evaluation index system and the corresponding method.According to an extensive investigation of hydrogeological conditions and pollution sources,the authors made an analytical test on the groundwater vulnerability by using the GIS technique.Some conclusions have been reached:Concerning the groundwater narrow vulnerability deduced from the hydrogeological conditions,the riverbed,floodplain,first terrace and city center with artificial earth fill are most vulnerable,but they are not consistent with the realistic pollution distribution;as for the general vulnerability of groundwater pollution that takes into account land use and pollution source distribution,the building area and the northern suburb irrigation area are most vulnerable,and these areas agree basically with the distribution of groundwater pollution.It is thus thought that the narrow vulnerability is suitable for extensive areas where the difference of human activity impacts is relatively small,and the general vulnerability fits urban areas where the difference of human activity impacts is fairly obvious,which means that the two methods have their respective reasonably suitable conditions.