Fig. 6

Fungal community composition at phylum (A) and genus (B) levels with varying SPSB treatment concentrations. CK (no biochar), S1 (2.5% w/w biochar + soil), S2 (5% w/w biochar + soil), S3 (7.5% w/w biochar + soil). The significant differences are determined by the Tukey test, with different lowercase letters indicating significant differences between groups (P < 0.05)