YANG Haijun1,2, XU Yunhai1, LIU Yabin1, WU Peng2, SHU Qian2, LUO Liaofang2, Wu Gang2
(1. College of Plant Protection, Hunan Agricultural University, Changsha 410128, China;
2.Environmental Monitoring Technology Limited Company of Hunan Zhongcheng, Changsha 410000, China)
Abstract: In order to assess the heavy metal pollution in pond sediments of Xiawan and Laoxiawan ports in the Qingshuitang industrial zone of Zhuzhou, 25 ponds in the study area were divided into three sub-divisions (S1, S2 and S3) and a total of 32 sediment samples were collected on December 11th, 2017, and contents of pH, Pb, Cd and As in sediment samples were measured. The geo-accumulation index (Igeo) and the potential ecological risk index (Eri) were used to evaluate the pollution and ecological risk of Cd, Pb and As. The results showed that contents of Cd, Pb and As in sediments of S1, S2 and S3 all exceeded their background soil values of Hunan, and were 657, 44 and 12 folds higher than the background values, respectively, suggesting that Cd was the major pollutant in ponds of the Qingshuitang industrial area. The variation coefficients analyses showed that Cd, Pb and As contents in sediments distributed discretely and were affected greatly by input sources. The Igeo assessment indicated that average Igeo values of Pb, Cd and As in sediments were 4.87, 8.78 and 2.95, respectively, corresponding to severe, serious and moderate pollution levels. The contamination order of sediments by heavy metals was S3>S1>S2. Results of the Eri assessment indicated that Eri values of heavy metals in pond sediments followed an order of Cd＞Pb＞As, Eri values of Cd obtained from 3 sediments were in the range of 9396-24617, indicating the extreme strong ecological risk; Eri values of Pb were in the range of 101-309, showed strong ecological risk in S1 and S3 and moderate ecological risk in S2; Eri values of As were in the range of 74-138, showed strong ecological risk in S1 and S3 and moderate ecological risk in S2. In summary, pond sediments around Xiawan and Laoxiawan Ports were polluted seriously by Cd, Pb and As with an order of S3>S1>S2. Thus, corresponding treatment measures, such as dredging, stabilizing or landfilling, should be taken according to the pollution levels.
Keywords: sediment; heavy metal pollution; pollution characteristics; risk assessment
EARTH AND ENVIRONMENT Vol.47, No.5, Tot No.331, 2019, Page 671-679
