Study On The Influence Of Coal Gangue Filling In Huainan Mine Reclamation-area

Huainan is an important energy base in East China.The exploitation and utilization of coal resources has promoted the development of Huainan economic,at the same time, also caused ecological environment problems,such as land subsidence, gangue mass storage. Using coal gangue filling reclaimed in Huainan coal mine has decades of history, but the study on land reclamation of coal gangue still rare.Based on the systematical research of reclamation soil quality at home and abroad mining area, taking Xinzhuangzi and Panyi mine reclamation area as the study area, Through the investigation of reclamation time, thickness of covering soil, distribution of vegetation in the study area and the surrounding envoriment, identified the collecting scope of the samples of soil and coal gangue in two reclamation area. This experiment collected102soil samples,16coal gangue samples,8plant samples.Focus on the analysis on3aspects.1Research on characteristic of reclamation coal gangueCombined with the field measurement and laboratory experiments, the reclaimed soil and coal gangue characters were relatively systematically researched.The results show that:(1) Water content rate of coal gangue is low, all samples are less than5%, lower than the normal farmland. And pH value is greater than8, showed alkalessency.(2)Refered to the second national soil fertility classification standards, the content of available K in Xin Zhuangzi reclamation area is rich, but in the two reclamation area available P and N are in the deficiency state, and the organic matter content is plentiful.(3) The contents of heavy metals in reclamation area are basically higher than the background value in Huainan, but lower than the secondary standard for soil environmental quality.2Research on characteristic of reclamation soil(1) Compared with the comparative soil properties, the moisture content, organic matter, available potassium, available phosphorus, available nitrogen content is low in reclamation area, generally soil moisture between6%-11%, basic suitable for crop growth, but part of the region is at a low level. Water content of surface soil is higher than the lower soil layer;(2)According to figure23to figure34, content of reclamation area soil samples of six kinds of heavy metal elements Cu、Zn、Cr、Ni、Cd、Pb,including four kinds of heavy metals Cu、Zn、Ni、Cd、Pb higher than the background value of soil in Huainan,but below the secondary standard for soil environmental quality. The sample part of Gr、Cd was higher than the secondary standard for soil environmental quality,Xinzhuangzi reclamation area three samples exceed the standard rate from top to bottom were25%、12.5%、12.5%and75%、87.5%、87.5%, Panyi reclamation area three samples exceed the standard rate from top to bottom were12.5%、25%、0and75%、62.5%、75%.(3) In Xinzhuangzi mine reclamation area, in the reclaimed soil physicochemical index is better than that of planting trees in the reclaimed soil for planting crops, the field management and fertilization can be beneficial to restoration of the fertility of the soil reclamation area.3The influence of the filling gangue on reclaimed soil(1) Analysis on reclaimed soil quality by evaluating soil productivity. Using soil productivity index correction model for MPI reclaimed productivity evaluation, the results show that the reclaimed soil productivity increase year by year, at present, only the control65.26%.(2) Analysed the relation of heavy metal content between coal gangue and reclamation soil, the results show that the coal gangue has the possibility of heavy metals migration to the reclamation of soil, but in addition to Cd, Cu、Zn、Ni、Cr and Pb did not exceed national the secondary standard for soil environmental quality, there is no pollution, that is to say, migration and accumulation of heavy metals pollution in coal gangue is a slow process,heavy metals in coal gangue in addition to Cd and Cr, other4kinds of heavy metals did not cause pollution of the reclaimed soil health.(3)Studied the relationship of heavy metal content between reclamation soil and the in plant root system, the results showed that the plant roots to absorb heavy metals is out of step with heavy metal content in soil, it mainly depends on the size of the plants absorb heavy metal itself ability, but the soil PH, Eh, moisture content, organic matter and other nutrient, microorganism and so on all affect the effectiveness of heavy metals in rhizosphere, which affects the absorption of root system.