Table 3.
Spearman’s correlation coefficients between the amoA OTUs (classified at the species level) and amoA gene copy number (determined by qPCR), N2O emission flux and mineral N (NH4+-N and NO3–-N) values.
| Speciel-level classificationa | N2O-Nb | NO3–-N | NH4+-N | amoA gene copy number |
|---|---|---|---|---|
| Betaproteobacteria_Nitrosomonadaceae_Nitrosomonas_Nitrosomonas sp. JL21 | –0.1 | –0.02 | 0.36∗∗ | –0.01 |
| Betaproteobacteria_Nitrosomonadaceae_Nitrosospira multiformis | –0.43∗∗∗ | –0.32∗ | 0.20 | –0.47∗∗∗ |
| Betaproteobacteria_Nitrosomonadaceae_Nitrosospira multiformis ATCC.25196 | 0.05 | 0.12 | –0.00 | 0.75∗∗∗ |
| Betaproteobacteria_Nitrosomonadaceae_Nitrosospira sp. 9SS1 | 0.19 | 0.25 | –0.14 | 0.76∗∗∗ |
| Betaproteobacteria_Nitrosomonadaceae_Nitrosospira sp. KAN8 | 0.08 | 0.11 | –0.23 | 0.24 |
| Betaproteobacteria_Nitrosomonadaceae_Nitrosospira sp. PJA1 | 0.29∗ | 0.34∗∗ | –0.11 | 0.84∗∗∗ |
| Betaproteobacteria_Nitrosomonadaceae_Nitrosospira sp. TCH711 | 0.259 | 0.26 | –0.25 | 0.66∗∗∗ |
| Betaproteobacteria_Nitrosomonadaceae_Nitrosovibrio sp. RY3C | 0.28∗ | 0.30∗ | –0.04 | 0.81∗∗∗ |
| Betaproteobacteria_Nitrosomonadaceae_uncultured.Nitrosospira sp. | –0.05 | –0.22 | 0.06 | –0.26 |
| Betaproteobacteria_unclassified | –0.06 | –0.19 | –0.16 | –0.72∗∗∗ |
| Unclassified | –0.22 | –0.26 | –0.19 | –0.16 |
The amoA-AOB OTUs were assigned to their taxonomic affiliations of ammonia-oxidizing bacteria (AOB) by comparison to sequences in the amoA database from FunGene. a Significant difference: ∗p ≤ 0.10, ∗∗p ≤ 0.05, and ∗∗∗p ≤ 0.01; b (mg N m–2 d–1). Bold values means significant correlation.