Study On The Heavy Metal Geochemical Process Of The Coastal Wetland In Tangshan

The coastal wetlandsfrom the luanheestuary to Jianhe estuary in Tangshan,were chosen,sampling their surface sediments.X ray fluorescence spectrometry(XRF),atomic absorption spectrometry(AAS)and inductively coupled plasma mass spectrometry(ICP-MS)were used to test the samples of heavy metal contentrations.The gap characteristics and the granular image analysis system software were used to analyze the granular of the surface sediments of the coastal wetlands in Tangshan.The research contents include the classification of surface sediments,the identification of feature minerals,the content of heavy metals and the characteristics of their occurrence.On this basis,the migration of heavy metals is discussed and the sedimentary environment is evaluated.Through studying the horizontal and vertical distribution characteristics of heavy metals,further analyzing the correlation between them,the correlation of sediment types and sources of pollution,and the comprehensive pollution evaluation was conducted to infer the geochemical progress of conservation characteristics and and migration patterns of heavy metals in coastal wetlands of Tangshan,which can provide a scientific basis for the research on the environmental capacity of coastal wetland ecosystem in Tangshan.The resulted show that the sediment types of coastal wetland in Tangshan are mainly grit,fine sand,silt and clay,which contain mineral debris,rock debris and biological debris.Sedimentary environment is the coastal shallow sea sediments and delta deposits at oxidation state under mediumhigh energy hydrodynamic conditions.The horizontal distribution of heavy metals concentrates in the river mouth,sewage outfall,mining area,is easy to concentrate in the coastal shallow sea to reduce high salinity environment,and the vertical distribution is the trend from the surface to the middle to the lower layer showing first increase and then decrease,heavy metals elements are mainly from the erosion and transport of raw materials and industrial and agricultural production,the latter is the result of rapid industrial and urbanization process of pollution emissions.The concentrations of heavy metals in the surface sediments of coastal wetland in Tangshan were Pb> Cr> Zn> Cu> Cd> As> Hg,with the potential pollution level was at low and middle levis.