Study On The Losses Characteristic Of Nitrogen And Phosphorus Based On GIS In Panxie Mine

Based on the investigation and study of hydrology, vegetation, land use status in Pan Xie mine, this paper divide the type of land and arrange sampling points in subsided area.Through monitoring and analyzing water quality (including total nitrogen, nitrate nitrogen, ammonia nitrogen, total phosphorus, total phosphorus and other indicators) of sampling points in different time, the paper established difference figures on the dynamic change of water quality in sampling area, and then explored relationship between the loss characteristics of nitrogen and phosphorus and the distribution of subsidence. Mainly in space, content of total nitrogen, ammonia nitrogen and total phosphorus is big and obviously spatial differences in subsided water of Yangzhuang in Panji. The content of total nitrogen is over National IV class water standard and obviously spatial differences in subsided water of Xieqiao. In time, the content of nitrogen and phosphorus is more in May than in August in subsided water of Yangzhuang in Panji, it related to the local climate and the exogenous pollution. The content of nitrogen and phosphorus is more in October than in August in subsided water of Xieqiao, its overall volatility is large.Through monitoring and analyzing soil quality (including total nitrogen, nitrate nitrogen, ammonia nitrogen, total phosphorus) of sampling points in different time, the paper explored the relationship between the soil and water in the subsidence surrounding. It mainly included that the content of nitrogen and phosphorus increase with the increase of distance from subsidence water. The content of ammonia nitrogen, nitrate nitrogen and nitrite nitrogen were largely influenced by surrounding and rainfall conditions. The content of nitrogen and phosphorus is more in May than in august in subsided area of Yangzhuang in Panji. In Xieqiao, the content of nitrogen and phosphorus is more in east area than in west area and is more in October than in august.The paper simulated the release strength of nitrogen and phosphorus under different environmental conditions (including pH, sedimentation rate, water depth and temperature) thought laboratory experiments. The release accumulated quantity of nitrogen and phosphorus is highest under acid condition and is minimal under neutral condition. The release quantity of nitrogen is highest under slowly sedimentation rate and the release quantity of phosphorus is highest under fastest sedimentation rate. The quantity of nitrogen cumulative release is1.3m>1.6m>0.5m>1.0m under different depth. The quantity of phosphorus cumulative release is1.0m>1.6m>1.3m>0.5m under different depth. The suitable temperature of nitrogen and phosphorus is15℃.The Universal Soil Loss Equation (USLE) calculate the amount of soil erosion. Soil erosion modulus was derived by GIS interpolation method. Using the formula(regional soil erosion=∑single grid cell soil erosion modulus*grid cell area) calculate the regional average total amount of soil erosion2856.56t/a. According to the soil erosion intensity level, the subsided area belonged to moderate erosion, it was influenced by characteristics of coal mining subsidence,the surrounding vegetation and human activities.