Analysis of Spatial Variability of Soil Granules in early Stage of Reclamation at Opencast Coal Mine Dump in Loess Area

Quality of soil reconstruction is directly related to the vegetation recovery of opencast coal mine in loess area, therefore, research on soil properties of land reclamation has a very important role in mine ecological recovery. Based on an reclamation open coal mine dump loess area as the research area, semi-variance function as the basic tools, combined with traditional statistics and geo-statistics method, with statistical module of arcgis10.0, was applied to study the spatial variability of 0 ~ 40cm soil granules in early stage of reclamation, and using ordinary kriging method to draw the spatial distribution map of different particle size of soil granules. Results show that: (1) in early stage of reclamation, between 0 ~ 20 cm and 20 ~ 40 cm the component characteristic of different size of soil granules was similar, the average of silt content was all highest in the whole research region .(2) through the semi-variance function fitting, the theory model of semi-variogram of clay accord with spherical model, the semi-variance function of silt content in 0 ~ 20 cm level in line with the spherical model, in the 20 ~ 40 cm accord with the exponential model, the semi-variance model of sand in 0 ~ 20 cm fit with the spherical model, in the 20 ~ 40 cm semi-variance function in line with the exponential model, different size of soil granules content has spatial auto-correlation in a certain range, showing that has a medium spatial correlation. (3) the map can reveals the spatial distribution of soil granules in different levels, in 0 ~ 20 cm, on the horizontal direction of silt content in the high value area in the study area corresponds to the sand content is low in the area, both of them have good complementary, and in the vertical direction different soil granules content in the spatial distribution has no obvious regularity. This study can provide certain reference for loess area land reclamation of soil profile reconstruction and soil fertilization and amelioration.