Characteristics of Heavy Metal Pollution in Daninghe River and Modaoxi River of Three Gorges Reservoir Areas
三峡库区大宁河与磨刀溪重金属污染特征

In order to explore the potential ecological risk of heavy metals in Three Gorges Reservoir areas, the present study analyzed the heavy metals in sediments and wild crucain carp from Daning River and Modaoxi River which are two typical tributaries, and then the potential risk was evaluated using potential ecological risk index for sediments and comprehensive pollution index for fish, respectively. The results showed that concentrations of Zn and Cr were higher (Daning River: 78.31 and 83.98 mg ·kg-1; Modaoxi River: 99.03 and 94.20 mg ·kg-1), while Cd was the lowest (Daning River: 0.62 mg ·kg-1; Modaoxi River: 0.75 mg ·kg-1). Moreover, an obvious increasing trend of these elements was observed in these tributaries from upstream to downstream. For the wild crucain carp, the lowest concentrations of these elements were detected in muscles, and the highest concentrations were in the intestinal. However, no obvious increasing trend of these elements was observed from upstream to downstream. The potential ecological risk in sediments showed a high risk, while no risk was observed in fish.