Characteristics of Physical and Chemical Properties of Soil in Different Reclamation Years of Opencast Coal Mine Dump in Grassland

Taking the reclamation waste dump of open-pit mining area in east Inner Mongolia Steppe as our study area, we sampled field investigation and laboratory measurements to changes soil physical chemical properties during its recovery years. The objective this was aiming provide theoretical support for ecosystem restoration reconstruction grasslands Northwest China. results showed that: 1) mechanical composition all layers different years mainly composed silt, except 20-30cm; silt content significantly higher than control (CK), surface (0-5cm) 3 (2016) CK, but sand lower CK; 2) In early stage vegetation succession, were different. With increase years, TOC TN decreased, TP did not change Based on above results, characteristics succession discussed. research have certain significance practical guidance value ecological areas north