Geochemistry Research Of Heavy Metal Of Hulun Lake

Hulun Lake is located in semi-arid temperate zone and continental climate with high latitudes, which is the largest freshwater lake in the central of arid region in Asia; it has been included in the List of emphasis of wetlands in international and accepted as World Biosphere Reserve by UNESCO. It is not only the important fishery of freshwater waters, also the largest comprehensive nature reserves mainly to protect the grassland, wetland systems and rare endangered birds in northeastern China. Hulun wetlands and Daxinganling forest build the ecological barrier of northeast even north in China together. So, it has occupies an extremely important position to examine the eutrophication.Combination method and theory of environmental geochemistry, sedimentology and soil science, this study analyze content and fractionation of surface sediment and core of Hulun Lake, which of Cu, Pb, Zn, Cd heavy metal element's environment geochemistry characteristic conducts the research and makes the appraisal to the surface deposit present situation to provides the basic data for the Inner Mongolian lake heavy metal's prevention and control of pollution. The results are described as follows:1. Determine the spatial distribution character and chemical speciation of heavy metals Cu, Pb, Zn, Cd in surface sediments of Hulun lake. Heavy metals Cu, Zn exist mainly in residual, Pb in residual fraction and the manganese oxides is the dominant speciation and Cd associated with carbonates and organic matter is the main speciation. And came to the biological availability sequence Cd>Pb>Cu and Zn.2. The results indicate, the heavy metal of sediment of Hulun Lake has the compound pollution characteristic and the nature of homologous.3. Refering the environment soil background value of Hulunbeier, this article carries on the appraisal based on the accumulation exponential method and the latent ecological hazard law to the deposit heavy metal. Two method's results showed identically:the lake district deposit that Cd pollution is most serious, the partial position achieve the moderate pollution. Other three kind of elements are in the low pollution level, the pollution level in order to Cu> Pb> Zn.4. Cu content in most stations were higher than Ecological toxicity of sediment quality standards for the minimum level of heavy metals, means that the sediments were contaminated, most benthic organisms can withstand, but relevant departments should pay attention to.