Fig. 5

Relative contribution of factors to basal respiration by using multiple regression model. The factors were divided into four groups of predictors (plant properties, soil enzymes, soil properties, and soil microbial properties). The relative contribution of four groups were calculated as the sum of the standardized regression coefficients for each group. The averaged parameter estimates of multiple predictors were obtained from standardized coefficients. Components of the four groups of predictors are indicated by colored symbols on the right side of the figure; the lines through the symbols indicate the range of the effects. SWC = soil water content. DOC = dissolved organic carbon content