关键词: 埒子口, 沉积物, 重金属, 空间特征, 风险分析

Abstract: Based on the environmental monitoring data collected in May 2012 by the 17 monitoring stations in the Liezikou sea area, spatial distribution characteristics of seven heavy metals (As, Hg, Cu, Pb, Zn, Cr and Cd) in the surface sediments of the region were analyzed with the geostatistical method and their ecological risksassessed with the potential ecological risk index method. Results show that the contents of heavy metals in the sediments all reach meet with to Grade I criteria of the “National Standard of China for Quality of Marine Sediments”. On the whole, the surface sediments in the Liezikou sea area are generally good in environment quality. The high concentrations of heavy metals are mainly distributed in areas around the estuaries of the Xishu River and Guan River, while low concentrationsin areas on the sea side off the coast. Spatial distribution trend showed a strong correlation between northwest and southeast in heavy metal concentration. Pollutants in the outflows from the Xishu River and Guan River were the main sources of heavy metal pollution.  Good correlation and consistency was observed between integrated pollution coefficient and potential ecological risk index. Generally speaking, the Liezikou sea area lingers at low-moderate level of potential ecological risk. Cd is not only a majorheavy metal pollutant, but also an important ecological risk contributor. High ecological riskslie mainly in the sea areas around the estuariesof the Xishu River and Guan River , which suggests that pollutants discharged with river water from the two rivers pose a great risk to the marine ecological environment.

Key words: Liezikou, sediment, heavy metals, spatial characteristic, risk analysis