(1) 枣庄学院水环境保护研究中心城市与建筑工程学院

The South-to-North Water Diversion Project is one of the biggest water transfer projects with the largest beneficiary population in the world. Nansihu Lake is the biggest reservoir lake in the east route of South-to-North Water Diversion Project. This study analyzed contents distribution and speciation characteristics of beryllium(Be),antimony(Sb) and thallium(Tl) in surface sediments of the Nansihu Lake. Their environmental risks were evaluated by multiple methods. Based on the results given by the predecessors,the toxic response factors of Be,Sb and Tl were defined in this paper. The results showed that the average contents of Be and Sb were a little higher than their background values,and Tl content was lower than its background value. Speciation analysis showed that the residual forms of Be,Sb and Tl accounted for over 65%,70%,and 84% respectively,while the contents of the acid soluble was very low which led to low mobility and bio-availability. The surface sediments of Nansihu Lake had low Be,Sb and Tl enrichment degree, and therefore the ecological risk was low. Be,Sb and Tl were mainly from nature and ancillary from human activity. Different from Be and Tl,the main human activity source of Sb might be atmospheric settlement. Distributions of Be,Sb and Tl in the sediments were affected by particle size,TOC,and Al/Fe/Mn to some extent.