Fig. 3: Spatial commonness and rare fungi.

A The relationship between abundance and commonness of the overall soil fungal communities in arable lands (n = 156; orange) and grasslands (n = 61; green) across all five countries. Abundance is represented by the cumulative abundance of OTUs, which was calculated as the square-root transformed number of reads per sample. Cumulative abundance curves were created by averaging and summing up the ordered abundances. Commonness represents decreasing rank abundance of OTUs. Difference between the two land use types was mainly due to rare taxa, i.e., while abundant OTUs (higher ranked on the left) are similarly abundant in both land-use types, grasslands had a higher number of rare OTUs (lower ranked OTUs towards the end of the curves). B Spatial commonness or site occupancy of the overall soil fungal communities as revealed by the abundance of OTUs and the number of sites they were present at. Commonness represents the number of sites that the OTUs were present at, and it was calculated by square-root transforming the OTU abundance and then log-transforming to plot against the number of sites occupied. Common OTUs were present in a higher number of sites while rare OTUs were restricted in fewer sites. C Relationship between the overall fungal diversity and agricultural intensity for arable sites (n = 156). The Y axis represents the principal coordinate 1 of the overall OTUs using Bray-Curtis similarity whereas the X axis represents the agricultural intensity index calculated from agrochemical applications, tillage intensity, and crop diversity. Error bands indicate 95% confidence interval.