Study Of The Wetland Manganese Distribution In Poyang Lake And Influencing Factors Of Heavy Metals

Wetlands are an important part of the Earth’s ecological environment surviving breeding sites for many plants and animals. Wetland soils constitute an integral part of the wetland environment.Manganese has a very important role in wetland soil, on the one hand, as the sensitive elements of the environment, it has a cushioning effect,on the other hand,as the manganese oxide has a strong adsorption, it has very important role on the migration and transformation process of heavy metals of wetland soil. The lake is the gathering places of water system. Produced by upstream mining, smelting, heavy metal contaminants deposit and accumulate in here the hydraulic transport, then the content of heavy metals in the lakes region in the wetland soil will be gradually increased, so the study of heavy metals in the soil of lakes and wetlands appear is very important. Cu、Pb、Zn、Cd. In Jiangxi region, the exploitation of metal deposits of the Poyang Lake upstream has a rather long history, the main heavy metal pollutants is Cu, Pb, Zn and Cd.This study uses the on-site determination and laboratory simulations to study Systematicly and comprehensively the typical of Poyang Lake wetland soils physical and chemical properties, the activity of manganese and total manganese distribution characteristics. In this basis, This study uses the laboratory simulation method to study the influencing factors of wetland soil and manganese oxide adsorbing of heavy metal and the factors in releasing heavy metals.The main findings are as follows:(1) Totally Poyang Lake wetland belongs to weak to restore sexual environment, a strong reduction environment in individual regions, the relatively high content of organic matter, It is typical of wetland environments and its pH is weakly acidic. From the sample layer, the pH increases with increasing depth and its steady state is in12cm.(2) With higher levels of total manganese in wetland soils. It is2.5to11times compared with the national average, the content of The exchangeable manganese sf the activity of manganese tends to increase from the upper to the lower while the easily reducible manganese showed a decreasing trend from the upper to the lower.(3) Wetland soil and the manganese oxide adsorption of heavy metal is a complex process. The process is faster in the early and slower in the latter. The equilibrium time is about2h. The adsorption of heavy metals in the amount of manganese oxide is much larger than the wetland soil adsorption of heavy metals in quantity. Wetland soil absorption of heavy metals affects by external influences than the manganese oxide, such as pH, ion concentration.(4) Wetland soils and oxidation of manganese adsorb and then release the heavy metals is also a composite process, pre-release speed is large and small in the latter, equilibrium time for wetland soil is3h, for manganese oxide is approximately5h.After adsorbing of heavy metal, wetland soil release more.relatively speaking, manganese oxide release heavy metals is faster and to be relatively stable, and manganese oxide adsorption of heavy metals little affected by environment, and the pH, ion concentration, water and soil is an important factor in the release of heavy metals for the wetland soil.