School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai, 200093, China.
College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China.
Environ Sci Pollut Res Int. 2018 Jan;25(1):855-866. doi: 10.1007/s11356-017-0425-0. Epub 2017 Oct 24.
The Yangtze River estuary (YRE) and Hangzhou Bay (HZB) is of environmental significance because of the negative impact from industrial activities and rapid development of aquaculture on the south bank of HZB (SHZB) in recent years. This study investigated the distribution and risk assessments of trace metals (Cr, Cu, Zn, Hg, Pb, and Cd) accumulated in surface sediments by sampling in YRE, outer and south HZB. Copper and Zn concentration (avg. 35.4 and 98.7 mg kg, respectively) in surface sediments were generally higher than the background suggesting a widespread of Cu and Zn in the coastal area of Yangtze River Delta. High concentrations of Cu (~ 42 mg kg), Zn (~ 111 mg kg), Cd (~ 0.27 mg kg), and Hg (~ 0.047 mg kg) were found in inner estuary of YRE and decreased offshore as a result of terrestrial input and dilution effect of total metal contents by "cleaner" sediments from the adjacent sea. In outer HZB, accumulation of terrestrial derived metal has taken place near the Zhoushan Islands. Increase in sediment metal concentration from the west (inner) to the east (outer) of SHZB gave rise to the input of fine-grained sediments contaminated with metals from outer bay. According the results from geoaccumulation index, nearly 75% of samples from YRE were moderately polluted (1.0 < I < 2.0) by Cd. Cadmium and Hg contributed for 80~90% to the potential ecological risk index in the YRE and HZB, with ~ 72% sites in HZB under moderate risk (150 ≤ RI < 300) especially near Zhoushan Islands.
长江口（YRE）和杭州湾（HZB）由于近年来 HZB 南岸（SHZB）工业活动和水产养殖业的快速发展，对环境造成了负面影响。本研究通过在 YRE、外海和南 HZB 采样，调查了表层沉积物中痕量金属（Cr、Cu、Zn、Hg、Pb 和 Cd）的分布和风险评估。表层沉积物中 Cu 和 Zn 的浓度（平均分别为 35.4 和 98.7 mg kg）普遍高于背景值，表明长江三角洲沿海地区 Cu 和 Zn 的分布广泛。YRE 河口内部 Cu（42 mg kg）、Zn（111 mg kg）、Cd（0.27 mg kg）和 Hg（0.047 mg kg）浓度较高，这是由于陆地输入和相邻海域“清洁”沉积物对总金属含量的稀释作用，导致这些金属在近海处的浓度降低。在外海 HZB，舟山群岛附近发生了陆源衍生金属的积累。SHZB 从西（内）到东（外）的沉积物金属浓度增加，导致来自外湾的受金属污染的细颗粒沉积物的输入。根据地积累指数的结果，YRE 近 75%的样品受到 Cd 的中度污染（1.0 < I < 2.0）。Cd 和 Hg 对 YRE 和 HZB 的潜在生态风险指数的贡献为 80%90%，HZB 约有 72%的地点（72%）处于中度风险（150 ≤ RI < 300），特别是在舟山群岛附近。
