【摘要】 在珠江口东侧航道附近的桂山岛周围7个位点采集表层沉积物样品,采用Hakanson生态危害指数法和污染系数初步考察了表层沉积物中重金属污染状况和生态危害程度,并由重金属富集因子分析了沉积物中重金属污染来源。结果表明,沉积物中Cu、Pb、Cd和Zn的富集达到中等污染水平,而Ni尚处于低污染水平;沉积物中重金属的生态危害目前仍属轻微。沉积物中Cu、Pb和Zn污染主要受人为活动输入的影响,而Cd主要来源于沉积物底质材料风化。利用建立的连续萃取程序对沉积物中重金属赋存形态进行了考察,结果表明,Cu和Zn主要以残留态和硫化物结合态存在,其次为有机质结合态和还原态;Pb和Ni主要以残留态存在,其次为硫化物结合态。重金属酸溶态含量都较低。更多还原

【Abstract】 The surface sediment samples were collected from 7 sites in Guishan island near the eastern waterway of the Pearl River Estuary,and the pollution degree and ecological risk of heavy metals in surface sediments were preliminarily investigated by Hakanson’ risk index and pollution coefficient.The sources of heavy metals were studied by the enrichment factor.The results showed that the contents of Cu,Cd,Pb and Zn reached the moderate level polluted,however,the content of Ni was low.The ecological risk of heavy metals was still slight.Cu,Pb and Zn were mostly from the anthropogenic sources,and Cd mainly resulted from the weathering processes of crustal materials or non-anthropogenic sources.The speciation of heavy metals in surface sediments was partitioned by the propositional sequential extraction procedure.The results showed that Cu and Zn mainly were in the residual fraction and sulfide bound fraction,and followed by reducible fraction and organic matter bound fraction.Pb and Ni mainly were in the residual fraction and followed by sulfide bound fraction;and the acid soluble fraction of heavy metals were low.更多还原