洪湖水体中微量元素的空间分布特征、风险评价及潜在来源识别

摘要

Five trace elements including Zn, Cu, Cd, Cr and As were investigated in surface water from ten typical sampling sites in Honghu Lake. The consequence indicated that all of the detected trace element levels were within the allowed standard of China's safe water guideline. The hazard quotients (HQ) and the hazard index (HI) value levels of all the five heavy metals in all sampling sites did not exceed the acceptable risk limits of non-carcinogenic value through the selected assessment method. Pearson's correlation analysis and principal component analysis (PCA) indicated that Zn and Cu mainly originated from the natural alluviation and non-point agricultural sources, whereas Cr and As were mainly derived from industrial effluents. Moreover, Cd mainly originated from both non-point agricultural and industrial pollution sources. In addition, cluster analysis (CA) implied that cluster 1 (including S3, S5, S6 and S10) was considered the set of high pollution sites and cluster 2 (including S4 and S9) was identified as the set of moderate pollution sites.%本文对洪湖10个代表性采样点表层水中的锌(Zn)、铜(Cu)、镉(Cd)、铬(Cr)和砷(As)5种微量元素进行研究.研究结果表明,洪湖水体中该5种微量元素的浓度均未超过中国的水质安全标准.各个采样点中5种微量元素的单独非致癌风险及综合非致癌风险水平均未超过相应评价方法的可接受风险限值.皮尔森相关分析和主成分分析结果表明洪湖水体中的Zn和Cu主要来源于天然冲击作用和农业面源污染,Cr和As主要来源于工业废水,而Cd同时来源于农业面源污染和工业污染.此外,各个采样点的聚类分析结果表明采样点S3、S5、S6和S10被判定为重度污染区域,而S4和S9为中度污染区域.