作　　者： ; ; ; ; ;

机构地区： 同济大学海洋与地球科学学院

出　　处： 《海洋地质与第四纪地质》 2012年第1期19-25,共7页

摘　　要： 三峡水库蓄水后长江中下游干流和水库内悬浮物地球化学组成如何变化是一个重要科学问题。相态分析表明,在长江重庆至南通段干流悬浮沉积物中,不同元素在酸不溶相和酸溶相所占比例不同,且存在一定的区域变化,Ca和Mg在酸溶相中比例相当高,而Al、Fe、K、Na等元素主要赋存于酸不溶相中。长江悬浮沉积物元素组成的空间变化特征主要受流域风化物质的来源、风化程度和水动力环境控制。重金属元素组成研究显示,在三峡库区及下游地区由于受人类活动影响,Pb、Zn、Co、Cu等在悬浮沉积物中呈现明显的累积趋势。三峡水库内沉积动力环境的不均一性导致水体中元素组成的垂向变化。 The study on the concentrations of major elements in the suspended sediments collected from the Changjiang mainstream at Chongqing and the downstream areas reveals that element concentrations are dif- ferent in the acid leached and residual fractions. The percentages of Ca and Mg are high in the leached frac- tion, while Al, Fe, K and Na are mainly concentrated in the residual fraction. The compositions of major elements show somewhat regional pattern of variations, primarily reflecting the controls of sources of the weathered materials, weathering intensity and hydrodynamics of the river. The distribution of heavy met- als suggests that Pb, Zn, Co and Cu accumulate in the suspended sediments, probably due to the contami- nation of the river by intense human activities around the Three Gorges Reservoir and its downstream are- as. The instability of hydrodynamic environment in the Three Gorges Reservoir leads to the compositional variation of heavy metals in vertical profiles.

关 键 词： 元素 悬浮沉积物 化学相态 人类活动 长江

领　　域： [天文地球] [天文地球]