中文摘要：

推迟的沉积在河和存款里从流动的水吸附污染物质到床上。然而，在河床沉积积累的污染物质可以为时间的一个长时期通过食物链影响简历社区。学习这个问题重金属的集中(Cr， Cd， Hg， Cu， Fe， Zn， Pb 并且作为) 在 2006-2007 期间在长江的中间、更低的活动范围在水，沉积，和鱼 / 无脊椎动物里被调查。重金属的集中比在水里在沉积更高是 100-10,000 时间。Benthic 无脊椎动物由于他们的最近在他们的纸巾有重金属的相对高的集中到污染沉积。而 phytoplanktivore 鱼例如银鲤鱼，积累了重金属的最低集中， Benthic invertivore 鱼有重金属的中等高的集中。Cu， Zn，和 Fe 的集中比 Hg 高， Pb， Cd， Cr，并且作为在织物样品。重金属的集中比在湖沉积在河沉积是更低的。相反地，重金属的集中比在湖水里在河水里是更高的。当进水身体的一个污染事件经常是临时的时，污染物质的效果可能由于他们全神贯注于沉积的趋势是长寿的然后释放进食物链。重金属在下列顺序被集中：底部材料 > 居于水底的鱼和 benthic 动物志 > 中间降低的层鱼 > 上面中间的层鱼 > 流水。

英文摘要：

Suspended sediment adsorbs pollutants from flowing water in rivers and deposits onto the bed. However, the pollutants accumulated in the river bed sediment may affect the bio-community through food chain for a long period of time. To study the problem the concentration of heavy metals （Cr, Cd, Hg, Cu, Fe, Zn, Pb and As） in water, sediment, and fish/invertebrate were investigated in the middle and lower reaches of the Yangtze River during 2006-2007. The concentrations of heavy metals were 100-10,000 times higher in the sediment than in the water. Benthic invertebrates had relatively high concentrations of heavy metals in their tissues due to their proximity to contaminated sediments. Benthic invertivore fish had moderately high concentrations of heavy metals whereas phytoplanktivore fish, such as the silver carp, accumulated the lowest concentration of heavy metals. The concentrations of Cu, Zn, and Fe were higher than Hg, Pb, Cd, Cr, and As in the tissue samples. The concentration of heavy metals was lower in the river sediments than in the lake sediments. Conversely, the concentration of heavy metals was higher in river water than in lake water. While a pollution event into a water body is often transitory, the effects of the pollutants may be long-lived due to their tendency to be absorbed in the sediments and then released into the food chain. The heavy metals were concentrated in the following order： bottom material 〉 demersal fish and benthic fauna 〉 middle-lower layer fish 〉 upper-middle layer fish 〉 water.