Table 4.
Taxonomic classification of 16S rDNA sequences in microcosms with soil and leaf litter from Populus tremuloides.
| Mean proportion of sequencesa | ||||
|---|---|---|---|---|
| PT (60 d) | GVb (60 d) | HP (60 d) | No litterc (0 d) | |
| Acidobacteria | 23.4 | 19.1 | 13 | 19.8 |
| Actinobacteria | 3.2 | 9 | 9.2 | 24.4* |
| Bacteroidetes | 2.4 | 3.4 | 3.8 | 0* |
| Chloroflexi | 3.2 | 1.1 | 3.8 | 1.2* |
| Cyanobacteria | 8.9 | 4.5 | 9.9 | 0* |
| Firmicutes | 0.8 | 0 | 0 | 1.2 |
| Gemmatimonadetes | 1.6 | 1.1 | 1.5 | 2.3 |
| Nitrospira | 0 | 0 | 0 | 1.2 |
| Planctomycetes | 0 | 0 | 1.5 | 1.2 |
| Proteobacteria | ||||
| α-Proteobacteria | 25.8 | 32.6 | 26 | 15.1* |
| β-Proteobacteria | 5.7 | 1.1* | 9.9 | 9.1 |
| δ-Proteobacteria | 8.1 | 11.3 | 8.4 | 3.5 |
| γ-Proteobacteria | 3.2 | 4.5 | 3 | 3.5 |
| Unclassified Proteobacteria | 2.4 | 0 | 0.8 | 1.2 |
| TM7 | 0 | 0 | 0 | 1.2 |
| Unclassified | 10.5 | 11.2 | 6.9 | 12.8 |
| Verrucomicrobia | 0.8 | 1.1 | 2.3 | 2.3 |
PT, parental type litter (60 d); GV, GUS vector; HP, high proanthocyanidin content.
Abbreviated soil types are followed by days of incubation.
The mean in this column marked with an asterisk (*) is significantly different (P = 0.002) than the mean for microcosms with other incubated soils (i.e., treatment affect corresponding to the mean of PT and HP soils in same row) according to Poisson linear regression analysis.
Means in this column marked with an asterisk (*) are significantly different (P < 0.002) than the mean for microcosms sampled 60 d later (i.e., incubation effect corresponding to the mean of other soils in the same row) according to Poisson linear regression analysis.