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Heavy metals as environmental pollutants, due to their special chemical and geochemical properties and toxic effects, has been subject to extensive attention. The estuary wetland is a typical non-steady-state complex system, coupled with runoff, ocean, atmosphere, biological and geological processes and human activities, and many other factors interact most active. Estuarine tidal flat not only has unique environmental features and ecological value, but also rich in land resources, and diverse functions become the focus of many problems of the tidal flat. Estuarine tidal flat of the Yangtze River, Pearl River and other places have been more domestic, and the Yellow River Delta wetland is still very rare. This paper focuses on the variation of heavy metals in the sediments of the lower reaches of the Yellow River water and estuarine wetlands study to examine the impact of the heavy metal content and distribution factors affect the lower reaches of the Yellow River water and sediment. The research results can not only enrich the understanding of the biogeochemical cycle of coastal wetlands protection and pollution control to provide a reliable scientific basis for the environmental management of the Yellow River mouth coastal wetlands. April 2009 (spring), June (summer) in the Yellow River mouth wetlands collect sediment samples; December 2008 November 2009 period, the Yellow River water samples collected in Lijin and suspended particulate matter samples on a monthly basis. Distribution characteristics and influence factors of heavy metals (Cu, Pb, Zn, Cr, Cd, As, Hg) in water, suspended particulate matter and sediments. The main conclusions are as follows: 1. Surface sediments of wetlands in the Yellow River Mouth, Cu, Pb, Zn, Cr, Cd, As, Hg average content for 22.1,53.8,78.4,60.5,0.25,7.7,0.055 μg / g, respectively, the content lower overall; except Pb, are in line with the national soil environmental quality of a standard. The heavy metal content in spring than summer. The content of heavy metals in surface sediments space quite different, and this difference is mainly caused by hydrodynamic and environmental differences. Columnar sediments of wetlands in the Yellow River Mouth heavy metal content vary widely, and there was more than peak-like distribution. Stations near the river, because the early diagenesis, the content of heavy metals in the core sediments trend with depth first decreases and then increases. The distribution of heavy metals in the core sediments is mainly affected by the redox conditions, organic matter and vegetation. Changes in the lower reaches of the Yellow River water concentrations of heavy metals season dissolved Cu, Pb, Cr, Cd, As, Hg concentrations range: 1.07 ~ 3.18,0.14 ~ 0.47,0.13 ~ 0.24,0.17 ~ 0.39,1.39 ~ 2.12 , 0.11 ~ 0.14μg / L; range of particulate Cu, Pb, Cr, Cd, As, Hg concentrations were: 0.45 ~ 7.33,0.36 ~ 4.01,0.36 ~ 5.32,0.005 to 0.082,0.02 to 0.41,0.002 to 0.025μg / g. Various heavy metals tailor particulate based. Has a significant negative correlation between the concentration of particulate heavy metals in SPM, flow. , An important factor in the flow rate and the concentration of suspended particulate matter is influencing the changes. The annual flux of dissolved state of Cu, Pb, Cr, Cd, As, Hg were 24.02,4.11,2.22,3.81,24.59,1.60 t / a; particulate Cu, Pb, Cr, Cd, As, Hg years Fluxes were 406.07,334.14,350.46,5.11,21.19,1.65 t / a.
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