Relationship between soil depth and terrain attributes in karst region in Southwest China

摘要: Soil depth generally varies in peak-cluster depression regions rather complex ways. Because conventional soil survey methods these require a considerable amount of time, effort, and consequently relatively large budget, new are required karst regions. This study explored the relationship between terrain attributes abstracted from digital elevation models (DEMs) at different spatial resolutions Guohua Karst Ecological Experimental Area, representative region Southwest China. A uniform 140 m × 140 m grid combined with hillslope methodology was used to select 171 sampling points where measured. Nine primary secondary attributes, such as elevation, slope, aspect, especial catchment area, wetness index, length-slope factor, stream power relief degree land surface, distance ridge mountains, were computed DEMs resolutions. The optimal DEM resolution determined by Grey relational analysis (GRA) reflect correlations attributes. GRA revealed that 10-m can best attributes; therefore, this for multiple linear stepwise regression (MLSR) analysis. result MLSR indicated TWI, could explain about 61.4 % total variability area. WTI be evaluate very well. proposed approach may applicable other areas larger scale.