Distribution Characteristics and Ecological Risk of Heavy Metals in Surface Sediment of East Dongting Lake and Its Lake Inlet
In order to investigate the pollution characteristics of TI, Sb and other heavy metals in surface sediments of East Dongting Lake and its Lake inlet, the concentrations of 13 kinds of heavy metals including TI, Sb, Hg, Cd, As, Pb, Cu, Ni, Co, Cr, V, Mn and Zn in nine sediments sampling sections were analyzed. The spatial distribution, sources and ecological risk of those heavy metal were evaluated. The results indicated that the average concentrations of each heavy metals in the sediment samples ranged from 0.180 mg·kg-1 to 762 mg·kg-1. The contents of each heavy metals were followed by the order: Mn>Zn>V>Cr>Pb>Cu>Ni>As> Co>Cd>Sb>TI>Hg. The pollution extent of sediments collected from S1(Xiangjiang lake inlet), S2(Miluo River), S4(Lujiao), S6(East Dongting Lake), S7(Yueyang Tower) and S9(Dongting LAke exit) were more serious. The sources of most heavy metals in sediments were similar, the first principal components were mainly from Xiangjiang River and Miluojiang River, Xiangjiang River played a leading role. V was mainly from the pollution around the lake. The pollution extent of each heavy metals in sediments by geo-accumulation index (Igeo) followed the order: Cd>Hg>Pb>As=Zn>Sb>V>Cu>Mn>TI>Co>Ni>Cr, and the study area was facing serious pollution. The potential ecological risk of each heavy metals in sediments by the potential ecological risk factor (Eri) were in the following order: Cd>Hg>Sb>TI>As>Pb>Cu>Ni>Co>V>Cr>Zn>Mn; The average potential ecological risk index was 555.1 (ranging from 217.9 to 1968), the study area was facing severe ecological risk, Cd and Hg were the major risk pollutants, followed by TI and Sb. The potential ecological risk of all sampling sites were followed by the order: S1>S6>S9>S7>S4> S2>S5(Bianshan)>S8(West Lake)>S3(Xinqiang River). Xiangjiang lake inlet (S1) was facing serious ecological risk, Lujiao (S4) to Dongting Lake exit (S9) were facing severe ecological risk, S1, S4, S6, S7 and S9 have become potential ecological risk regions.
East Dongting LakeLake inletsedimentheavy metalsecological risk
国家科技期刊平台
NSTL
万方数据
维普
