胜利矿区土壤养分空间变异特征与影响因素

研究矿区土壤养分空间变异特征对矿区土地复垦与生态保护具有重要意义。选取胜利矿区土壤作为研究对象，基于地统计学和GIS技术分析土壤养分的空间变异性，并探讨地形因子和土地利用类型对其影响。结果表明：研究区土壤pH、有机质、速效氮、速效磷、速效钾平均含量分别为8.073、21.588g/kg、82.914mg/kg、8.210 mg/kg、257.341 mg/kg。除pH属于弱变异外，其他养分均属于中等强度变异。各项养分指标均具有一定的趋势效应。pH的最适模型是球面模型，有机质、速效钾的最适模型是线性有基台模型，速效氮、速效磷的最佳拟合模型是指数模型。pH、有机质、速效氮表现为中等空间相关性；速效磷、速效钾呈弱空间自相关。pH值由中部向四周逐渐降低；有机质、速效氮高值区集中在西部高程较大的位置，低值区分布在受人类扰动较强的中东部；速效磷、速效钾没有呈现一定的分布规律。坡度、坡向、高程、地形湿度指数是造成土壤养分格局差异的主要地形因子；从土地利用方式看，采矿扰动是养分含量较低的重要原因，矿业用地养分含量显著低于耕地和草地。

Spatial Variability and Influencing Factors of Soil Nutrients in Shengli Mining Area

It is of great significance for the land reclamation and ecological protection of mining areas to carry out a research on the spatial variability characteristics of soil nutrients in mining areas. Therefore, based on the geostatistics and GIS techniques, the soil of the Shengli Mining Area was taken as a research object in this paper to perform an analysis on the spatial variability of soil nutrients and an investigation into the effect of topographic factors and land use types on the spatial distribution of soil nutrients. The results showed that the average contents of pH, soil organic matter, available nitrogen, available phosphorus and available potassium of the research area soil were 8.073,21.588g/kg,82.914mg/kg,8.210 mg/kg,257.341 mg/kg, respectively. Apart from a weak variation of pH, other soil nutrient indicators all belong to a moderate level of variation. All nutrient indexes have a certain trend effect. The optimal model for pH is spherical model, while the optimal-fit model for organic matter and available potassium is linear platform model, and available nitrogen and phosphorus can be well fitted by exponential model. There are moderate spatial autocorrelation of pH, organic matter and available nitrogen; but the spatial autocorrelation of available phosphorus and potassium is weak. Besides, pH decreases gradually from the middle to the four sides; while high value areas of organic matter and available nitrogen are concentrated in high-elevation regions in the west, and the low value areas of that are distributed in central and eastern regions which are under strong disturbance of human beings; for available phosphorus and potassium, there is no certain distribution regularities. At last, slope, aspect, elevation, and topographic wetness index are the main topographic factors that contribute to the difference in soil nutrient pattern. From the point of view of land use, mining disturbance is an important cause of low nutrient content. The nutrient content of mining land is significantly lower than that of farmland and grassland.