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Wetlands in the Pearl River estuary mudflats soil, leaching and desalinization research Salinity Changes coexistence of anion and cation migration and transformation of chemical forms of heavy metal, and crop effectiveness period for the development and utilization of soil heavy metal pollution shoals provide a scientific basis. Salt ions on the the different desalination stage of soil pore water and soil through the shoals of the Pearl River estuary wetland soil leaching experiments, the various heavy metal content and the content of heavy metals in different forms of monitoring and analysis. The results show that the rate of decline than leaching after leaching of salt ions: Na 80.3%, K 73.5%, Mg2 86.6%, Ca2 90%, Cl-81.8%, SO42-98.2%, the pH of the soil pore water The value of an upward trend; rate of decline of heavy metals in the soil are 26.6% of Cd Pb 22.8%, Cu 16.9%, Cr 7.9%, Zn 9.1%, the rate of decline of heavy metals bound to carbonate: Pb 77.8%, respectively, Cr 61.7%, Cu 68.4%, Zn 67.1%, Cd 7.1%, Fe-Mn oxide bound Cd and Pb is 49.1% and 23.5%, respectively. Change the chemical forms of soil heavy metals leaching and desalinization process migration status. Pearl River estuary mudflats soil containing different salt leaching after soil culture experiments, the preparation of its salt, heavy metal content similar nutrient solution for hydroponic experiments to study the leaching and desalinization of heavy metals in crops effectiveness. The results showed that the soil culture experiments, the amaranth the roots of Cd, Pb, Cr, Ni, Cu content gt; leaves and stems of the content, leaching and desalinization can inhibit root uptake of heavy metals Cd, Pb, Cr, Cu, promote the absorption of heavy metals stems absorption of Cd, Pb, Cu, Ni, can be suppressed; amaranth stems different desalination gradient, the transport capacity of Zn strongest and weakest Cr transport capacity. The hydroponic experiments under different salinity gradient, the distribution pattern of the amaranth the body Cd, Pb, Cr, Zn, Ni is also the root part of the gt; stems and leaves part of the Cu stems and leaves part gt; the roots part: nutrient solution salinity gradient descent can inhibit root absorption of Cd, Pb, Cr, Cu, promote the absorption of Zn, stems and leaves of Cd, Cu absorption decreased absorption of Zn and Ni will be enhanced; the size of the root absorption ability of different heavy order Zn gt; Cd gt; Cu ≈ Ni gt; Cr gt; Pb, stems and leaves of metal absorption capacity size of the order Zn gt; of Cu gt; Cd gt; Ni gt; the of Cr gt; Pb; the different stems transit heavy metal capacity order Cu gt ; Zn gt; Cd, Ni, Cr, Pb.
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