不确定条件下的下辽河平原地下水本质脆弱性评价  

Assessment of groundwater intrinsic vulnerability in the Lower Reaches of Liaohe River Plain under uncertain conditions

作　　者：孙才志[1] 奚旭 

机构地区：[1]辽宁师范大学城市与环境学院,辽宁大连116029

出　　处：《水利水电科技进展》2014年第5期1-7,共7页Advances in Science and Technology of Water Resources

基　　金：教育部博士点基金(20122136110003);国家自然科学基金(40501013)

摘　　要：针对地下水系统中水文地质参数的随机性和模糊性会对地下水脆弱性评价结果产生较大误差问题,在辨析参数不确定性特点基础上,利用蒙特卡罗法同时对随机性参数和模糊性参数赋值,并结合DRASTIC模型对下辽河平原的地下水本质脆弱性进行评价。通过模拟计算出模糊性参数在不同α截集水平下地下水脆弱性指数不同可能性下的累积分布曲线,得到不同保证率、不同可能性情况下地下水脆弱性指数的隶属函数,并从脆弱性和不确定性两个角度对各分区地下水脆弱性进行对比分析。分析结果表明:Ⅰ1区脆弱性程度相对最高,不确定性程度一般;Ⅰ2、Ⅰ3、Ⅱ1和Ⅱ3区的脆弱性程度较高,且Ⅰ2、Ⅰ3区的不确定性程度相对最高,Ⅱ1和Ⅱ3区的不确定性程度最低;Ⅰ4、Ⅱ2、Ⅲ和Ⅳ区的脆弱性程度相对较低,其中Ⅱ2和Ⅳ区的不确定性程度较低,Ⅰ4区的不确定性程度一般,Ⅲ区的不确定程度较高。较传统评价过程,本次地下水脆弱性评价综合参数的不确定性分析得出了不确定条件下地下水脆弱性的隶属函数,结果切合客观实际。The randomness and tuzziness of hydrogeological parameters in the groundwater system can lead to great error to the evaluation results of groundwater vulnerability. This study is based on the analysis of parameters＇ uncertainty characteristics by using the Monte Carlo method to assign stochastic and tuzzy parameters at the same time combined with DRASTIC model to evaluate the groundwater intrinsic vulnerability of Lower Reaches of Liaohe River Plain. Through simulation to calculate the different possibilities-cumulative distribution curve of groundwater vulnerability index under different a-cut level of tuzzy parameters, it is possible to deliver the membership interval of groundwater vulnerability index from possibilities-cumulative distribution curves under different reliabilities. Furthennore, the groundwater vulnerability in each partition can be analyzed from vulnerability angle and uncertainty angle. The results show that： area Ⅰ has the highest degree of groundwater vulnerability and average degree of uncertainty; area Ⅰ2, Ⅰ3, Ⅱ1 and Ⅱ3 has a relatively high degree of groundwater vulnerability, the degree of uncertainty in Ⅰ2and Ⅰ3 are relatively highest and the degree of uncertainly in Ⅱ1 and Ⅱ3 are relatively lowest; and groundwater vulnerability in area Ⅰ4, Ⅱ2, Ⅲ and Ⅳ are lower, the degree of uncertainty in area Ⅱ 2 and Ⅳ are relatively low and the degree of uncertainly in area Ⅰ4 is general while the degree of uncertainty in region Ⅲ is higher. Compared with traditional evaluation process, the groundwater vulnerability assessment based on the analysis of parameters＇ uncertainly it is possible to calculate the membership tunction of groundwater vulnerability index under uncertain conditions. The results agree with the objective reality.

关 键 词：地下水本质脆弱性 水文地质 DRASTIC模型 不确定性 蒙特卡罗法 仪截集 累积分布曲线 下辽河平原 

分 类 号：P641.8[天文地球—地质矿产勘探]