Environmental Chemistry On Trace Elemental Mercury In Sediment-Water-Interface In Poyang Lake, China

Environmental pollution is one of fatal problems faced in 21 century. There are amounts of lakes located in China. Poyang Lake, which is the largest freshwater in China is the famous representation. Based on the financial supported from The National Nature Science Foundation of China (Grant: 40103009, 40573044) and the Excellent Young Teachers Program of MOE, China (Grant: 20011766) to supervisor Professor Deng, the environmental chemistry of mercury in the sediment-water-interface (SW1) in Poyang Lake was investigated in details.The researched contents are including: ?Studied the environmental chemistry in SWI on trace mercury of Poyang Lake in winter; ?Vertical profiles on active mercury, inert mercury, total mercury and dissolved ions of iron, manganese, S^2- and pH value, dissolved organic carbon(DOC) in the series porewater samples in the areas of Kangshan, Ruihong and Hukou, Poyang Lake were determined; ?Total mercury(expressed as THg) in sediments, mercury adsorbed onto hydroxides of iron and manganese(expressed as Hg-oxal), associated to organic matters(expressed as Hg-H₂O₂), and mercury existed in the crystallized sulphides (expressed as Hg-pyrite) in winter were extracted by a sequential extracted procedures, and then were analysed; ?Vertical distributions on TFe, TMn, Fe-oxal, Mn-oxal, Fe-H₂O₂, Mn-H₂O₂ respectively were also done; ?Total sulphur, acid volatile sulphur, minerals of sulphide and elemental sulphur in sediment samples in winter were also extracted and analysed.Solutions presented in the projects can be summarized as follows: Determinations and distributions of mercury species in porewaters and sediments in winter, Poyang Lake were studied. Based on those series date (summer's data got by our research group was also included), the behaviours of distribution, transfer and transform of mercury in Poyang Lake were carried out. It is demonstrated that the vertical distributions of mercury in the porewaters and sediments in the three regions have good correlation and the seasonally changes are distinctness. The horizontal distributive feature of the concentration of mercury within the Lake is that outflow of the lake > inflow of the lake> the centre of the Lake.