雷州半岛近海表层沉积物重金属污染评价

本文测定了雷州半岛近海43个表层沉积物中重金属元素（Hg、Cu、Zn、Cd、Pb和Cr）和类金属元素（As）的含量，并分析其空间分布特征，采用潜在生态风险指数法对重金属的污染风险等级进行评价。结果表明:各站位中Hg、Cu、Zn、Cd、Pb、Cr和As的平均含量分别为0.037×10?6、15.62×10?6、66.33×10?6、0.13×10?6、26.71×10?6、59.54×10?6和11.20×10?6，均超过南海北部陆架区沉积物背景值；研究区综合潜在生态风险指数RI平均值为130，属于低生态风险，但雷州半岛东侧鉴江入海口海域和西侧流沙湾近海海域达到中等生态风险程度，Hg是主要的污染因子；与前人2010年结果比较，雷州半岛近海沉积物中Cu、Zn、Cd、Pb、Cr、As含量呈现逐渐增加的趋势，反映了人类活动对该海域的影响。

Assessment of the heavy metal pollution in the offshore surface sediments of the Leizhou peninsula

The content and spatial distribution characteristics of heavy metal elements (Hg, Cu, Zn, Cd, Pb, Cr) and metal-like element (As) in 43 surface sediments from the offshore Leizhou peninsula were determined. The risk grade of heavy metal pollution was evaluated by the potential ecological risk index method. The results showed that the average contents of Hg, Cu, Zn, Cd, Pb, Cr and As in each station were 0.037×10?6, 15.62×10?6, 66.33×10?6, 0.13×10?6, 26.71×10?6, 59.54×10?6 and 11.20×10?6, respectively, which exceeded the background values of sediments in the northern shelf area of the South China Sea. The mean value of RI in the study area was 130, which at low ecological risk. However, the moderate ecological risk was found in the Jianjiang river's estuary on the east side of the Leizhou peninsula and the offshore area of Liusha bay on the west side, and Hg was the main pollution factor. Compared with the results in 2010, Cu, Zn, Cd, Pb, Cr, and As contents in the Leizhou peninsula's offshore sediments showed a gradual increase, reflecting the influence of human activities on the study area.