Figure 4

Component plotting of multiple variables including soil organic carbon content (%) based on the principal component analysis (PCA). (A) PCA plot with observations; (B) Correlations between principal components and predictor variables. AGB = aboveground biomass, LU = land use, BD = soil bulk density (g cm−3), Eh = soil oxidation–reduction potential (ORP, mV), SOC = soil organic carbon concentrations (%).