3.5 Relationships between soil bacterial, fungal community
and soil properties
Redundancy analysis (RDA) depicts the relationships between dominant
phyla of soil bacterial and fungal communities and nine selected soil
physicochemical properties and microbial biomass (Fig. 5). RDA showed
that pH (r2=0.91, p=0.001), TN
(r2=0.76, p=0.035), and MBN
(r2=0.73, p=0.005) were the most significant
environmental factors explaining variability in bacterial community
composition, with the first two axes accounting for 59.57 and 15.16% of
the total variation (74.73%), respectively (Fig. 5a). Proteobacteria,
Firmicutes, and Bacteroidetes were negatively correlated with pH and
MBC/MBN, while significantly positively correlated with other
properties; Acidobacteria were negatively correlated with pH, TN and AN.
RDA showed that MBN (r2=0.84, p=0.001), pH
(r2=0.76, p=0.001), AN (r2=0.78,
p=0.001) and MBC (r2=0.79, p=0.001) were the most
significant environmental factors explaining variability in fungal
community composition, with the first two axes accounting for 22.78 and
12.22% of the total variation (35.0%), respectively (Fig. 5b).
Ascomycota and Chytridiomycota showed a positive correlation with pH and
MBC/MBN, and a negative correlation with other soil properties;
Basidiomycota showed a positive correlation with pH, SOC, MBN, and AK.
Discussion