地下水过量开采的概率风险分析

Probabilistic risk analysis for excessive exploitation of groundwater

应用一种概率风险分析方法评价了济宁市地下水水位降落漏斗区的风险度。该方法引入了可靠度和严重度来进行分析评价,可靠度从宏观上反映了含水层系统的安全可靠程度,而严重度从微观上详细地刻画了含水层系统的易破坏程度。其中,影响可靠度大小的因子主要有可开采量和实际开采量,严重度大小的主要影响因子包括实际开采量、净补给、降深和含水层的初始饱和厚度。在可靠度和严重度计算结果的基础上,利用ArcG IS软件计算了漏斗区风险度的空间分布。结果表明:占研究区总面积5.53%的中部地区风险度最大,而西部和南部的风险度相对很小,符合该地区实际的水文地质条件和地下水资源的开采现状。

A probabilistic approach is applied to determine groundwater overdraft risk in Jining City. It is a combination of system reliability and severity analyses. In this approach, allowable and actual groundwater withdrawals are evaluated to determine system reliability, and severity which describes the failure degree of aquifer system and depends on actual production volume, net recharge, drawdown and initial saturated aquifer thickness. Spatial risk map is obtained from the severity and probability-index maps by use of geographic information system （GIS）. The result indicates that the central part of the study area, which covers 5.53% of the total aquifer area, is the most risky area while western and southern parts are the least risky areas. The result is in agreement with the conditions of actual hydrogeological and groundwater resources exploitation.