Spatial distribution characteristics of soil and vegetation in a reclaimed area in an opencast coalmine

Abstract

Opencast coal mining activities result in severe damage to soil and vegetation, and the reconstruction of soil and vegetation is critical in opencast coalmine areas. To better understand the spatial distribution characteristics of soil and vegetation in opencast coalmines, a spatial correlation analysis was conducted on the soil and vegetation properties of the Anjialing and Antaibao opencast coalmines in the Pingshuo coal mining area in China. A total of 70 sample points were selected using grid and transect methods, from which the soil and vegetation properties were determined. The spatial autocorrelation, spatial clustering, and spatial variability of the soil and vegetation indicators were analyzed using global Moran’s index, local Moran’s index, and the geostatistics method based on ArcGIS 10.2 or Geoda 7.0 analysis software. The soil and vegetation indicators were divided into three categories, including vegetation indicators (arbor quantity, AQ; average diameter at breast height, ADBH; herb coverage, HC; average tree height, ATH; canopy density, CD), soil physical properties (soil bulk density, BD; clay content; silt content; sand content; gravel content, GC), and soil chemical properties (soil organic matter, SOM; total nitrogen, TN; available phosphorus, AP; available potassium, AK; pH). There was a strong global autocorrelation among ADBH, clay content, AQ, HC, and SOM. Dumping and reclamation activities affected the spatial distribution characteristics of soil and vegetation. The “high-high” and “low-low” types in all the indicators possessed a large spatial distribution, and the soil and vegetation properties had relatively high spatial clustering. This study can provide a reference for the reclamation practice in opencast coalmine areas.