瓯江口附近海域表层沉积物重金属时空变化特征及其潜在生态危害评价

根据2006年和2013年航次对瓯江口附近海域调查的资料,分析了沉积物中重金属Cu、Pb、Zn和Cd的时空变化特征,并对其潜在生态危害进行了评价.结果表明,相比2006年,2013年调查海域表层沉积物中Cu和Zn平均含量有所增加,但经student-t检验,两组结果间不存在显著性差异,而Pb和Cd有显著性降低;与国内外其它河口相比,其含量处于中等水平.从空间分布上看,两次调查表层沉积物中重金属的空间分布有明显差异,同次调查中各重金属的空间分布总体趋势相似.通过潜在生态危害指数法对调查海域表层沉积物中重金属潜在生态风险性的评价表明,2013年调查海域重金属总的潜在生态危害指数整体属于中度生态危害水平,较2006年有明显降低.

Spatial and temporal variation and potential ecological risk evaluation of heavy metals in surficial sediments from the adjacent waters of the Oujiang Estuary

This paper analyzed the distribution characteristics of Cu、Pb、Zn and Cd in surficial sediments from the adjacent waters of the Oujiang Estuary, and potential ecological risk level of those metals was evaluated based on the survey data in 2006,2013. The results showed the average concentrations of Cu and Zn had a slight increase from that in 2013 compared with that in 2006, but the difference had no remarkable significance with student's t test; then the contents of Pb and Cd significantly reduced. In common with other estuarys at home and abroad, the overall content of these metals in the study area was at a middle level. According to the spatial distribution of heavy metal contents, there was biggish difference between the two surveys. The potential ecological risk of heavy metals to the ocean ecology system was assessed with adopting Hakanson ecological risk index, the total potential ecological risk index as a whole was moderate level at 2013, what was significantly lower than that in 2006.