Fig. 6
Paths and effects of tillage and organic matter (OM) input on soil properties, microbial biomass, phospholipid fatty acids (PLFAs) and crop production according to partial least squares path modeling (PLS‒PM). OC, soil organic carbon; TN, soil total nitrogen; TP, soil total phosphorus; AN, inorganic available nitrogen; OlsenP, Olsen-available phosphorus; MBC, microbial biomass carbon; MBN, microbial biomass nitrogen; PC1 and PC2 were the first two principal components of PLFAs. A goodness of fit > 0.6 indicated that the PLS‒PM model was acceptable. The numbers on the arrows are the standardized path coefficients and the widths of the arrows are proportional to the strengths of the path coefficients. Continuous red and blue arrows indicate significant positive and negative relationships (p < 0.05), respectively. The gray dashed arrows indicate no significant relationships (p > 0.05). R2 indicates the proportion of variation explained. The numbers on the rectangles are the loadings between the latent variables and observed variables.
