Effects of substrate quality and microbial groups on soil decomposition activities.

Each value indicates the proportion of explained variation by each factor, calculated using redundancy analysis (RDA) and a permutation test (999 permutations). All 5 decomposition activities were used as explained variables. Note that the sum of the biomarkers that indicate the same microbial group, and not individual biomarker lipids, was used here to reduce the number of explanatory variables in the RDA. Indicative biomarker lipids are specified in Materials and Methods. All variables were scaled before the RDA. *, **, and *** indicate significant effects at P<0.05, 0.01, and 0.001, respectively, by the permutation test.