The Effect Of Coal Mining On Soil Water Movement In Aeolian Sand Land Of Shendong Coal Field

Based on the importance of soil water to sandy vegetation, two-years field experiment withthree different types (Salix psammophila, Populus simonii, Artemisia ordosica) in Bulianta miningarea of southeast Mu Us Sandy Land in the Shendong Coalfield was carried out in different period(stage before mining, fracture development stage, stage during mining, subsidence stage,stabilization stage) to assess the effects of large-scale underground mining on the soil watermovement such as soil moisture dynamic changes, soil water infiltration and evaporation, soilphysical properties at sandy area, and then the process of soil water movement in cracked sandyand silt soils were simulated by the Hydrus-2D software compared with the monitoring data by themethod of soil column in laboratory. The results showed that: affected by vegetation type, miningsubsidence, and micro-topography, the interpolation map by Kriging method showed that soilmoisture presented a significant different plaque distribution pattern; in the layer of0~100cm, soilmoisture turned to be seriously deficit in the subsidence stage and the summer of stabilizationstage, and then were restored in the fall of stabilization stage. Mining subsidence caused changesin soil physical properties and reduction in water holding capacity, and influenced the process anddepth of water infiltration, and increased soil evaporation rate. The effect of cracks on soil waterinfiltration and evaporation were different with different vegetation type. By principal componentanalysis,12factors affecting soil moisture were analyzed, among all the factors, vegetation type,soil water movement parameters and soil physical properties were the main affecting factors forsoil moisture. Simulation results showed that soil water vertical changes were affected by the"point-line source" infiltration coupling effect in the condition of fixed cracks.