Fig. 6: Correlations between CO2 emission rate and soil properties under different oxygen and temperature conditions.

Line width reflects the Pearson correlation coefficient, while line color reflects the nature of the correlation (positive or negative) and the associated p value. In the matrix of pairwise comparisons, Pearson correlation coefficients are indicated using a color gradient. ***p < 0.001, **p < 0.01, *p < 0.05. BD bulk density, A/O-A ratio of alkyl-C to O-alkyl-C, DOC dissolved organic carbon, H2O-PHE water-soluble phenolics, Fe-OC, Fe-bound organic carbon, MBC microbial biomass carbon, MBN microbial biomass nitrogen, b-Chao1 Chao1 richness of bacteria, f-Chao1 Chao1 richness of fungi.