Spatial Distribution Of Typical Soil Nutrients And The Impact Factor In Pingshuo Mining Area

Open-pit coal mines are one of the most drastic anthropogenic land disturbances. Under the influence of mining activities original soil characteristics changed radically.It is difficult tobe improved rapidly that soil is affected by different kinds of reclamation technologies, land use type and so on after land reclamation. With the time goes by, the spatial variation of soil nutrients could also change. Soil nutrientsaffect plant growth directly and agricultural production indirectly. Accurate information is essential for applications of mine reclamation soil quality evaluation, and would be helpful in adjustment of land reclamation modes.The goal of this paper were to explore the current level of the five kinds of soil nutrients, to illustrate their spatial variability and distribution patterns, to describe the relationships between soil nutrients and environmental impact factors, and to build accurate prediction models. The main results are listed as follow:(1)Soilnutrients within research area are in large difference on variability. Among them, SOM, AP content show the strong variability; N, AK content show the moderate variability; soil pH is characterized by the weak variation.(2) Moderate spatial dependent were obtained for N,AK and pH content, indicating the spatial distribution of soilnutrients is effected by the combination of anthropogenic and natural factors; Weakly spatially dependent were obtained for AP which is mainly composed of human activities such as agricultural management measures;SOM shows strong spatial correlation.(3) To observe the spatial distribution map of five soil nutrients by ordinary kriging interpolation, overall, SOM and N content in the mining area are lower than surrounding natural soil contents, on the contrary,AK and AP content are higher. Soil pH value change is not obvious.(4) The results of ANOVA and post-hoc showed that slope showed significant regional impacts on SOM content; aspect do not showed significant regional impacts on five kinds of soil nutrients content; land use type only showed significant regional impacts on SOM,N and AP content.(5) Regression kriging could fully employ easily acquired auxiliary variables,and the prediction accuracy of regression kriging was greatly improved by compared with ordinary kriging. Different interpolation methods and parameter settinghave an effect on soil variable spatial interpolation precision. The results showed with SOM as covariates, Cokriging method have a highly accuracy in predicting soil pH value, compared with inverse distance weighting method, spline function method and ordinary krigingmethod.