Cation Exchange Properties of Subsurface Soil in Mid-Subtropical China: Variations, Correlation with Soil-Forming Factors, and Prediction

Soil cation exchange property (SCEP) is important in soil development and environmental buffering. However, the variations SCEP its correlation with soil-forming factors subsurface are not fully understood. In this study, we quantified surface as a function of parent material, vegetation, hillslope position, type. Fifty upland profiles from mid-subtropical China were selected. The capacity (CEC) effective CEC (ECEC) significantly higher soils derived slate, Quaternary red clay (QRC), limestone than granite sandstone. had highest base saturation (BS) sum cations, lowest aluminum (Al) saturation. varied vegetation position. was mixed-forest whereas ECEC exchangeable acidity (EA) arable vegetation. Exchangeable potassium (K+) EA orders at strong phase. calcium (Ca2+), magnesium (Mg2+), CEC, BS intermediate prediction accuracy using random forest model that obtained multiple stepwise regression, best results (R2 = 0.92) soil. Our study indicated controlled by different could be effectively predicted properties subtropical China.