辽河流域水环境沉积物质量风险评估

Sediment quality risk assessment in Liaohe River basin

采集辽河流域浑河、太子河干流及大伙房水库共56个站点的表层沉积物样品,根据相平衡分配法的修正模型建立辽河流域沉积物重金属质量基准(Cu、Pb、Zn、Cd的SQC(基于CCC)分别为75.26μg/g、25.72μg/g、255.96μg/g、2.52μg/g),依据重金属急、慢性生物毒性风险确定辽河流域沉积物重金属质量三级标准,并创建沉积物质量风险评估方法——沉积物污染指数法(SPI),对辽河流域水环境进行沉积物质量风险评估,评估结果显示:浑河干流中下游、太子河中上游及大伙房水库库中、库尾处的沉积物质量状况为中风险,此沉积物重金属污染状况使长期生活在其中的底栖生物受到轻微重金属慢性毒性影响,其中浑河中游红透山铜矿处和细河上游沈阳工业区的沉积物质量风险极高。

56 surface sediment samples were collected from Hunhe River, Taizi River, Dahuofang Reser- voir in Liaohe River basin. Sediment quality criteria for heavy metals in Liaohe River basin were established by Equilibrium Partitioning（EqP） approach which was modified by author, the SQC （base on CCC） of Cu, Pb, Zn, Cd were 75.26 μg/g, 25.72 μg/g 255.96 μg/g and 2.52μg/g. Based on heavy metal acute and chronic aquatic toxic- ity, three grades sediment quality standards for heavy metal in Liaohe River basin were set and sediment pollution index （SPI） that a new assessing method was created accordingly. The author applied the established standards of Liaohe River basin to assess the sediment quality by SPI method, results showed that sediment quality in the mid- dle and lower streams of Hunhe River, up and middle streams of Taizi River, middle and end of Dahuofang Reser- voir were middle risk which meant that benthic survived in such heavy metal pollution sediment would suffer slight chronic toxicity effect of heavy metal. Hongtoushan Copper Mine that in the middle stream of Hunhe River and Shenyang Industry in the upstream of Xi River made extremely high sediment risk for discharging much wastewater to Liaohe River basin.