【作者】 宝金花；

【导师】 匡运臣； 何江；

【作者基本信息】 内蒙古大学 ， 环境科学， 2006， 硕士

【摘要】 由于人类和自然的相互作用，现代湖泊是时刻处在变化中的水动力环境，尤其是当接受了来自附近城市和工业点的大量人为污染物后，其沉积物来源变得更为复杂。在众多的污染物中，重金属由于其在环境中的持久性、生物地球化学可循环性以及潜在的生态威胁而倍受关注。沉积物是水环境中重金属的主要汇集场所，又是潜在污染源。了解沉积物中重金属含量和附存形态及其沉积物对重金属的吸附释放行为，对于探寻湖泊重金属的来源、评价污染现状、预测对整个生态系统的影响具有重要的现实意义。 本研究把包头市南海子上覆水、孔隙水及沉积物作为有机整体，首次开展了包头市南海子水-沉积物系统中重金属（Cu、Pb、Zn、Cd、Hg）的分布特征研究，探讨了沉积物有机质含量与沉积物重金属各形态之间的关系，同时还研究了不同环境条件下沉积物吸附释放重金属的特性。本研究获得如下初步结论： 1．上覆消解水样中的Cu、Pb、Zn、Cd、Hg含量均高于孔隙水中游离态重金属含量，上覆消解水中的Pb在B和E站位达到极值，Hg在E站位达到极值；孔隙水中的Cu、Zn在A、C、E站位达到最高。 2．南海子表层沉积物中Cu、Pb、Zn的生物有效态总含量均在湖心点最大，而Cd的生物有效态总量在C点达到极值，此变化趋势说明人类活动带来的污染物有明显的污染迭加作用。 表层沉积物中Cd和Hg的生物有效态总含量远高于残渣态。 南海子表层沉积物中汞的主要赋存形态为腐殖酸结合态，它的分布趋势与有机质的分布相类似，表明表层沉积物中腐殖酸结合汞与有机质具有相关性（r=0.718）。 3．柱状沉积物中Cu、Pb、Zn、Cd、Hg及有机质均随深度增加而有规律的递减，这种现状表明包头市南海子重金属污染在沉积物中以一定的速率迭加。 4．吸附实验结果表明：南海子表层沉积物对Cd²⁺的吸附等温线属于Langmuir型，沉积物更多还原

【Abstract】 Modern lakes are a complex dynamic system interacted by human and natural environments,especially when receiving large amounts of anthropogenic contaminants from nearby urban areas and industrial sites. Among the various contaminants, heavy metals are of particular concern due to their environmental persistence and biogeochemical recycling and ecological risks. Therefore, it is necessary to investigate the content, speciation, adsorption and release of heavy metals in sediment that the place of heavy metals accumulating and the place of heavy metals source in water environment. The result would make a great contribution to understand the heavy metal resources, pollution status and the affection to the ecosystem, and have a great significance to lake environmental protection.The Pollution Character of heavy metals in water-sediment system was for the first time studied combining the distribution character of heavy metals in the overlying water, sediments and pore water from Nanhaizi lake in Baotou city as a whole in this thesis.The relation between the content of organic matter and each speciation of heavy metals in sediment is discussed. At the same time the adsorption and release characteristics of heavy metals with the change of environmental conditions are also studied. The primary fruits from the results are as follows:1.The total content of Cu Pb Zn Cd Hg in the digested overlying water is higher than the pore water. The content of Pb in the digested overlying water is higher than a kite in site B and site E. The content of Mercury is higher than a kite in site E. The total content of Cu Zn in the pore water is higher than a kite in site A . C and E.更多还原