Fig. 4: Species richness and relative abundance of soil fungal functional groups in response to precipitation seasonality and experimental drought.

Changes in species richness and relative abundance of the main soil fungal functional groups in response to seasonality and 14 years of throughfall exclusion (~50%) in a tropical lowland rain forest in Amazonia. Green, wet season; brown, dry season; boxplots—filled, control; empty, treatment. Total richness, number of OTUs in each functional group; total number for all samples per functional group in upper left corner of panels; total number per treatment per season inside plotted boxes; relative species richness, the proportion of OTUs assigned to a functional group relative to all OTUs assigned to functional groups; relative abundance, the proportion of reads. For total and relative species richness the complete pool assigned to a functional group consisted of 1335 OTUs. Significant differences as determined by paired t-tests or Wilcoxon signed-rank tests, corrected for multiple comparisons using the false discovery rate method are indicated by grey arrows; ⁺p < 0.08 (marginally non-significant); *p < 0.05; **p < 0.01; ***p < 0.001. Boxplots: centre line, median; empty square, mean value; box limits, 25th and 75th percentiles; whiskers, 1.5 times interquartile range; empty circles, outliers.