Distribution Of Nitrogen And Phosphorus In Different Types Of Huainan Coalmine Subsidence Areas

Coal accounts for about 70% of the primary energy consumption in China and will continue to play an important role in the energy use for a long time to come, due to limited domestic petroleum and natural gas resources and abundant coal reserves. However, with the exploitation and use of coal resources, the environmental problems brought forth by it become more and more serious. Many of the coal mining subsidence areas has formed ponds under the influence of groundwater, rain water, and surface run off. As one of the typical representative of huainan city, the nutrients of subsidence waters is worthy of attention in this city.A total of nine mining subsidence waters and two different steady state demonstration area in Huainan, were selected to study the distribution and migration of nitrogen and phosphorus, and sources of pollution. The main results are as follows:1) Based on the measured results, the contents of nitrogen and phosphorus load was serious in the studied areas. The nutrients level of Huainan mining subsidence waters were at high eutrophication level. And the results of this research gave implication of the importance of nitrogen pollution and phosphorus control. Data analysis in dicates that total nitrogen, nitrate nitrogen in water and pH and time settlement have good positive correlations, respectively. On the spatial distribution, there were very different in nitrogen and phosphorus in different coal ming subsidence waters.2) The results showed that the nutrients spatiotemporal distribution were different in Xinzhuangzi and Houhu. Organic nitrogen and particle phosphorus were the main specie in total nitrogen and total phosphorus. According to the discoveries of the comprehensive nutrition state index, Xinzhuangzi was in moderate eutrophication state, and Xinzhuangzi was in heavy eutrophic state. They showed the contents of nitrogen and phosphorus in Houhu and Xinzhuangzi were higher.3) According to concentration diffusion, we found that the contents of nutrients in pore water were much higher than that in overlying water in Xinzhuangzi, which showed that nitrogen and phosphorus in pore water were diffusing into overlying water. However, the contents of total phosphorus in overlying water were much higher than that in pore water in Houhu, which showed that phosphorus in overlying water were diffusing into pore water.the sediment played different roles in source and sink in Xinzhuangzi and Houhu subsidence waters.4) According to the contents of heavy metals in Xinzhuangzi and Houhu, The results of this research gave implication of the importance of Cr pollution. And the water in Houhu was found the metal pollution phenomenon on the basis of HPI calculation.5) Results showed that the Huainan coal mining subsidence water quality was polluted with human activities, which need people to give importance to it.