北部湾油田海域沉积物重金属生态危害评价

Ecological Risk Assessment of Heavy Metals in Sediments of Beibu Gulf Oilfield Sea Areas

利用北部湾油田海域沉积物重金属10年监测数据,基于标准指数法、富集系数法、潜在生态危害指数法,对Pb、Zn、Cd和Hg 4种重金属进行变化规律、富集特征和生态危害研究。结果表明:2013年,4种重金属标准指数均小于1,符合第一类沉积物质量标准,总体处于良好状态,2011年后Cd含量上升明显;2013年,重金属富集程度由大到小为Pb>Zn>Cd>Hg,Pb和Zn属于中污染水平,Cd和Hg属于低污染水平,2011年后Cd富集系数上升明显;多年来,4种重金属的生态危害指数均小于40,属于轻微生态危害。2011年后Cd生态危害指数增幅明显。与临近海域相比,Cd含量处于较高水平;与国内其他海洋油田相比,Zn含量处于较高水平。

Based on the data of heavy metals in sediments of Beibu Gulf Oilfield sea areas in recent 10 years,the distribution and enrichment of heavy metals(Pb,Zn,Cd and Hg)in surface sediments from Beibu Gulf Oilfield sea areas were discussed.The standard index,potential ecological risk index and sediment accumulating coefficient were used to analyze the contamination condition and trend in the studied area.The results are summarized as follows.2013,standard indexes of these four heavy metals were all less than 1,which were below the first degree of standard for marine sediments quality.2013,The order of accumulating degree was Pb>Zn>Cd>Hg,and the Cd accumulating coefficient rised significantlyafter 2011.These years,potential ecological risk factors of these four heavy metals were all less than 40,belongs to the slight ecological risk.Especially,the ecological risk of Cd rised significantly after 2011.Compared with the neighbor sea areas,the Cd content was higher.Compared with the other oilfield,the Zn content was higher.