苏北沿海沉积物的化学组成和重金属特征

苏北沿海沉积物的主要矿物组成为石英、伊利石、高岭石和绿泥石，主元素化学成分变化较大，反映沉积物物质组成差异大。重金属元素分析显示，Cd的富集系数明显高于其它元素，较高的还有Cu和Cr，Hg元素大多低于背景值；连云港、射阳、启东三个地方的变异系数较高，反映它们受人类活动影响大。比较连云港区沉积物不同时间的重金属含量发现，几乎所有重金属都明显增加，特别是新港区。对照沉积物质量标准，Cr的污染最严重，其次是Cd、Cu和As。

Chemical composition and heavy metal characteristics of sediments in the coast, northern Jiangsu Province

The mineral components of sediments in the coast of northern Jiangsu,China are mainly quartz, illite, kaolinite and montmorillonite. The compositions of major elements vary largely, which reflect the difference in the material constitution. Heavy metals of sediments from Lianyungang, Sheyang, Qidong have more varieties on the basis of analyses, showing more effects of the anthropogenic inputs in these areas. The enrichment coefficient of Cd is highest, and those of Cu, Cr are higher than the others. Comparing contents of heavy metals in sediments from Liangyungang Harbor in two periods, we conclude that almost heavy metals increase during the past decade, especially in new harbor area. Cr as a polluted element is in the first place in the research area, and Cd, Cu, As are in the next places referring to quality guidelines of sediment for heavy metals.