The Primary Study On The Distributions And Transformation Of The Different Species Mercury In Aha Reservoir

As a water supply for Guiyang living in regional area, Aha Reservoir was contaminated by the mine waste water and living waste water. Recent several years, the water body of Aha Reservoir concludes high levels of SO₄^2- ,iron and manganese. From March in 2005 to August in 2005, the concentration , distribution , transportation and fate of mercury species in lake water columns, lake tributaries water, sediment profiles and fish from Aha reservoir were measured and researched. Through the detailed studies reported in this thesis, some main conclusions were obtained as follows:1. Discernible seasonal change of different mercury in water body were obtained inAha Reservoir. The concentrations of total mercury(HgT) were 2.1 -19.5ng·L^-1, the average is 9.3ng·L^-1 ; The concentrations dissolved (HgD) ranged from1.7 to 9.0 ng·L^-1, the average is 4.1ng·L^-1 ;The concentrations particulate mercury (HgP) were 0.3- 14.8 ng·L^-1 ,the average is 5.2 ng·L^-1; The concentrations reactive mercury (HgR)were 0.1- 4.5 ng·L^-1 ,the average is 1.7 ng·L^-1.2. With regards to the whole sampling periods, the concentrations of HgP in Aha Reservoir water body were evidently correlated to the concentrations of total mercury, it shows that total mercury was mostly associated with particles mercury. The concentrations of methylmercury in water body were also evidently correlated to the concentrations of dissolved mercury. The dissolved mercury evidently effects the distribution and transportation of methylmercury. However, there is no correlated between methylmercury and total mercury.3. The dissolved mercury , reactive mercury , dissolved methylmercury levels in the water body of high flow period were much higher than those in low flow period. The distribution, speciation and levels of mercury within the Aha Reservoir water body were governed by several factors, such as the output of river , the release of sediment.4. Discernible seasonal change of total mercury and methylmercury in porewater were obtained during the sampling periods, with the concentrations in high flow period were generally higher than that in low flow period. The methylmercury in pore water column were evidently correlated to that of the sediment. Maximum levels...