Surface Soil Water Content Before and After Coal Mining and its Influencing Factors—A Case Study of the Daliuta Coal Mine in Shaanxi Province, China.

The spatial variability in soil water content in the Daliuta mining area in western China was studied before and after coal mining using ground penetrating radar and geostatistical methods. The relationships among soil water content, soil physical properties, topographical factors, and vegetation density were analysed using classical statistics. The average surface soil water content changed slightly between the two detection events at the centre of the subsidence, from 0.084 cm3/cm3 to 0.079 cm3/cm3; there, the distribution of the soil water content was more closely related to terrain than any of the other factors being considered. Along the subsidence boundary, the surface soil water content decreased significantly after mining, from 0.099 cm3/cm3 to 0.083 cm3/cm3 at one location. The total soil porosity, soil organic matter, and soil clay content were positively correlated with soil water content before mining. However, after mining, the relationship between total soil porosity and soil water content significantly strengthened while the relationships between other soil physical and chemical properties and soil water content weakened. Vegetation was determined to be the main factor controlling the surface soil water content before and after coal mining at one location in a small (1,600 m2) area of the subsidence boundary. [ABSTRACT FROM AUTHOR]