%moisture 1 Abandoned land Abiotic factors 1 Bacteria (microorganisms) 1 Biomass 1 Biotic factors 1 China 1 Forestry 1 Land use 1 Least squares approximations 1 Loess Plateau 1 Microbial abundance 1 Microbial abundances 1 Nitrogen 1 Nutrients 1 Organic carbon 1 Regression analysis 1 Robinia pseudoacacia 1 Securigera varia 1 Soil moisture 1 Soil organic carbon 1 Soil respiration 1 Soil temperature 1 Temperature 1 Temperature sensitivity 1 Variable importances 1 abandoned land 1 abundance 1 bacterium 1 biomass 1