The Spatial Variability Of Soil Physical And Chemical Properties Under Coal Mining In The Long River Basin Of Shanxi Province

The long river basin located in the southeast of Shanxi Province, is a typical hilly area where the coal resources are rich. The exploitation of coal in this area made a significant contribution to the energy security and the construction and development of economy. However with long time, high strength, extensive, large-scale exploitation of coal, especially the recovery is not in place after exploitation to the original ecology on the long River Basin has brought a series of problems such as land subsidence, water shortage and air pollution. It had a strong impact on local production and economic development.The oil is the foundation of human survival, and it is an important part of human agricultural production base and the natural environment of the earth surface system. The study of soil physical and chemical properties in mining area is the key to Land reclamation after mining, ecological agriculture and forestry, coordinated utilization and development of coal-land-water. It is the basis of solving the problems of ecological environment security and regional sustainable development in coal mining. In this paper, the influence of coal mining on soil physical and chemical properties in the long river basin is studied. It has very important theoretical significance and practical significance for the land reclamation and the coordinated utilization of coal-land-water in the mining area.This paper takes the 108 square kilometers of the river basin of Shanxi Province as the research area, through the method of field sampling and indoor analysis, mining area and non-mining area relative, with theoretical basis of soil science, geology, ecology and statistics, it quantitative analyzed the spatial distribution and spatial structure of 10 main physical and chemical properties of long River Basin under coal mining and simulated t soil saturated hydraulic conductivity and soil water characteristic curve of the study area. For the first time this study had a high density soil sampling, with the relative illumination of mining area and non-mining area, and quantitatively studied the characteristics and laws of spatial variability of soil physical and chemical properties in the local area, the main conclusions are as follows:(1) Compared with non-mining area, the soil porosity, soil particle, clay, organic matter, available nitrogen, available phosphorus, available potassium content of coal is decreased in different degrees, the soil moisture content and soil bulk density is increased, the soil desertification, salinization and alkalization phenomenon has been appeared for a certain extent. With the increase of depth, soil moisture and PH were also increased, organic matter and available nitrogen, available phosphorus and available potassium were reduced in mining and non-mining area, no obvious rules in other indicators.(2) The coefficient of variation of soil bulk density, porosity and PH is less than 10%, which is a weak variation; the remaining indicators are moderate variability. In addition to sand, PH and available phosphorus, the variation coefficient of the remaining indicators of mining is greater than that of the non-mining area. There is a significant positive correlation between the same physical and chemical properties of different depths, and the correlation of different physical and chemical properties in the same depth is not significant, it is basically not related.(3) The nugget coefficient of most the soil physical and chemical properties in mining and non-mining area is less than 25%, with strong spatial correlation, and spatial variability mainly are caused by structural factors. From the comparison between mining area and non-mining area, in addition to the individual indicators, it shows a trend that the nugget coefficient of non-mining area is greater than mine. In a certain degree, coal mining of mining area caused some damage to soil structure, and mining land reclamation after coaling; it changes the soil type, topography and soil parent material and so on. Of course, it is also related to the semi-arid climate in the hilly area of the river basin, the specific reasons still need to be further studied.(4) The plaque of the spatial distribution pattern of Kriging interpolation show that the soil physical and chemical properties own a high spatial heterogeneity, and each physical and chemical properties had a strong similarity with the depth of soil, also there were some differences. The distribution pattern of soil physical and chemical properties of the mining area and the non-mining area is significantly different; coal mining changes the spatial distribution pattern of soil physical and chemical properties in the mining area.(5) With the simulation of soil water movement characteristics, the surface soil saturated hydraulic conductivity and water characteristic curve were obtained in the study area. And it puts forward the feasible measures of land reclamation and soil improvement in mining area. Reconstruction of soil reclamation in the mining area is mainly based on Agricultural Reclamation and Forestry and animal husbandry land reclamation, physical and biological methods are used for soil improvement.