3.2 Soil bacterial community structure
Soil bacterial community structure and diversity was determined based on
16S rRNA gene using pyrosequencing technique. In total, 7, 922 OTUs were
obtained from 60 soil samples with the average number of 30,677 sequence
per sample. Based on the relative abundance of OTU, we found that
bacterial OTU richness (Figure 4a) and Shannon diversity (Figure 4b) in
the maize field showed no significant difference with those of woodland
irrespective of season (P > 0.05 for both). However,
the NMDS ordination based on the relative abundance of OTU using
Bray-Curtis distance showed that bacterial community structure in maize
field was clearly separated from those in woodland. Furthermore,
bacterial community structure from both land uses showed a clear pattern
along the depth and seasonal variance (Figure 4c), which was further
confirmed by PerMANOVA and ANOSIM analysis based on different land uses
(P <0.01) and seasonal change (P <
0.05) (Table S1).