Environmental Engineering Reference
In-Depth Information
it was not affected by nitrogen leached from the catchment's area in boreal littoral wetlands
[9]. The other genera representing more than 1.0% proteobacteria sequences were
Ectothiorhodosinus
,
Pseudomonas
, and
Steroidobacter
.
Pseudomonas
was one of the widely
studied PAH-degrading bacteria, it widespread in contaminated wetlands environment [29],
and was predominant microbial populations in the constructed wetland for nitrobenzene
wastewater [32].
The 1420 betaproteobacterial sequences were identified in Proteobacteria. The genus
Nitrosomonas
was the predominant genera with 222 assigned sequences, while the genus
Nitrosospira
was the second abundant genus with 217 sequences. They were also the first and
second most abundant proteobacterial genera, and both of them were belong to the family
Nitrosomonadaceae which were well known as the main ammonia-oxidizing microorganisms
contributing to N
2
O production in wetlands and sediments [31, 49, 50]. The genera
Ferribacterium
,
Thiobacillus
and
Sulfuricella
owned more than 1.0% of proteobacterial
sequences.
The fourth largest proteobacterial class was Alphaproteobacteria, with 1090 sequences
(over 19.3%). The dominating genus
Sphingomonas
in class Alphaproteobacteria was widely
distributed in wetland and sediments, due to its ability to survive in low concentrations of
nutrients, as well as to metabolize a wide variety of carbon sources [7, 51]. Except for
Sphingomonas
containing over 2.0% of the proteobacterial sequences (122 sequences), other
genera of Alphaproteobacteria represented less than 1.0% of the proteobacteria sequences.
3.2.2. Bacteroidetes
Bacteroidetes was the second abundant phylum in the present dataset, including 2244
sequences (nearly 17.8% of all bacterial sequences), which were assigned to 109 known
genera, with 868 OTUs and a Simpson diversity index of 0.0007 (Figure 4).
Figure 4. Treemap of observed Bacteroidetes taxons shown in their hierarchical order.
