Fig. 1: Enzyme activities (β-D-glucosidase, N-acetyl-β-glucosaminidase, acid phosphatase) and decomposition affected by multiple factors of global change.

a–d The left part of the graph (white background) shows the control and the single factor treatments. The dashed line shows the mean value of the control plots. Dots reflect the measured values (10 replicates each), marked with a black filled dot is the mean, the 95 % confidence interval is shown by the line passing through the dot. On the right side of the graph, the combination of all global change factors (dashed line as mean), is compared to the treatment combinations, from which each of the single factors is subtracted. Redundancy analysis (RDA) and variance partitioning were performed to quantify the relative contribution of each factor, as well as their interactions, and residual (biological noise or measurement errors), presented in the upper right corner of the panel. e–h To visualize the effect directions of factor addition and subtraction treatments, bootstrapped (n = 100) effect size of factor addition were plotted on the x axis and the effect of factor removal on the y-axis. Different factors of global change are represented by different colors. Factor effects on the diagonal red line indicate that the effect of the factor in the multi-factor background has the direction and intensity expected from the single-factor effect. Factor effects in the gray shaded area indicate that a factor in combination with other factors has a more negative effect than expected from the single factor effect. Dark gray areas (upper right) represent positive single factor effects that have a negative effect when combined with other factors (effect size of single factor positive, effect size of factor removal positive as well). Source data are provided as a Source Data file.