， 第 44 卷第 4 期 人 民 黄 河 Vol ． 4 4 Nont and Ecological Technology，Beijing 100048，China� Abstract� In order to study the pollution risk of heavy metals in the bottom sediment of Tonghui Ｒiver in Beijing，10 sites were selected to investigate the heavy metals in the bottom sediment of Tonghui Ｒiver and analyzd their sources． The contents of Hg，Zn，Cu，Cd，Cr，Pb and Ni all exceed the background values of river sediment in Beijing，and Hg is the most serious． The variation coefficient of heavy metals can reflect the influence of human activities on sediment． Hg，Cd and As have larger variation coefficients and are greatly disturbed by human ac- tivities，while Ni and Cr have smaller variation coefficients and are little disturbed by human activities． The soil accumulation index，biotoxic- ity risk and potential ecological risk index of S4，S7 and Hg samples in the study reach are larger． Pearson correlation analysis and principal component analysis show that the pollution source of Tonghui Ｒiver mainly comes from transportation． Key words� heavy metals� risk assessment� traceability� Tonghui Ｒiver ， ， ， 底泥是河湖的重要组成部分 受到外源污染后 有 100 条河流底泥重金属进行相关性分析发现
