选择九龙江河口水域的沉积物为对象,以地质累计指数法、生态危害指数法对该水域沉积物重金属的污染程度及潜在生态危害进行评价,并利用主成分分析法分析其可能的来源。地质累积指数结果表明,九龙江河口水域沉积物中Zn、Cr均属无污染,大部分站位的Cu、Pb、Hg、As为无污染或轻度污染,大部分站位的Cd则为轻度或中度污染:生态危害指数结果表明,九龙江河口水域沉积物重金属的潜在生态危害顺序为Cd〉Hg〉As〉Pb〉Cu〉Cr〉Zn;总体上九龙江河口水域的沉积物重金属污染属于中等生态危害;该水域重金属可能来源于有机质的降解以及工业排:亏和生活污水对沉积物的污染,其中前者为主要的可能来源。
By the Index of Geoaccumulation and the Potential Ecological Risk Index, a pollution assessment of seven heavy metals (Hg, Pb, Cr, Zn, Cu, Cd, and As) was made of the sediment in Jiulong River Estuary. The results of pollution assessment by Index of Geoaccumulation revealed Zn and Cr in this area belonged to none pollutants while Cu, Pb, Hg, and As in most stations were non or light pollutants. However, Cd in most stations was assessed as light or moderate pollutant. The assessment result of ecological risk revealed this area belonged to moderate potential ecological risk. The order of ecological risk was as the following, Cd〉Hg 〉As〉Pb〉Cu 〉Cr〉Zn. Principal component analysis was applied to estimate the possible sources of heavy metal pollution in this area. Results showed that degradation of organic matter and industrial wastewater were the main sources of heavy metal contamination, but the former was more important than the latter.