Anaerobic ammonium oxidation in sediments of surface flow constructed wetlands treating swine wastewater.
Anaerobic ammonium oxidation (anammox) was suggested to be involved in the nitrogen (N) removal process in constructed wetlands (CWs). Nevertheless, its occurrence and role in CWs treating swine wastewater have not been well evaluated yet. In this study, we investigated the diversity, activity, and role of anammox bacteria in sediments of mesoscale surface flow CWs (SFCWs) subjected to different N loads of swine wastewater. We found that anammox bacteria were abundant in SFCW sediments, as indicated by 7.5 × 105to 3.5 × 106copies of the marker hzsB gene per gram of dry soil. Based on stable isotope tracing, potential anammox rates ranged from 1.03 to 12.5 nmol N g-1dry soil h-1, accounting for 8.63-57.1% of total N2production. We estimated that a total N removal rate of 0.83-2.68 kg N year-1was linked to the anammox process, representing ca. 10% of the N load. Phylogenetic analyses of 16S ribosomal RNA (rRNA) revealed the presence of multiple co-occurring anammox genera, including "Candidatus Brocadia" as the most common one, "Ca. Kuenenia," "Ca. Scalindua," and four novel unidentified clusters. Correlation analyses suggested that the activity and abundance of anammox bacteria were strongly related to sediments pH, NH4+-N, and NO2--N. In conclusion, our results confirmed the presence of diverse anammox bacteria and indicated that the anammox process could serve as a promising N removal pathway in the treatment of swine wastewater by SFCWs.
Key Laboratory of Agro-ecological Process in Subtropical Region, Changsha Research Station for Agricultural & Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Science, No. 644, the Second Yuanda Road, Furong District, Changsha, Hunan, 410125, People's Republic of China.
Liang
L
Chen
Key Laboratory of Agro-ecological Process in Subtropical Region, Changsha Research Station for Agricultural & Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Science, No. 644, the Second Yuanda Road, Furong District, Changsha, Hunan, 410125, People's Republic of China. liufeng@isa.ac.cn.
Feng
F
Liu
Key Laboratory of Agro-ecological Process in Subtropical Region, Changsha Research Station for Agricultural & Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Science, No. 644, the Second Yuanda Road, Furong District, Changsha, Hunan, 410125, People's Republic of China.|College of Environmental Science and Engineering, Hunan University, Changsha, 410082, People's Republic of China.
Fen
F
Jia
Key Laboratory of Agro-ecological Process in Subtropical Region, Changsha Research Station for Agricultural & Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Science, No. 644, the Second Yuanda Road, Furong District, Changsha, Hunan, 410125, People's Republic of China.
Ya-Jun
YJ
Hu
College of Environmental Science and Engineering, Hunan University, Changsha, 410082, People's Republic of China.
Cui
C
Lai
Key Laboratory of Agro-ecological Process in Subtropical Region, Changsha Research Station for Agricultural & Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Science, No. 644, the Second Yuanda Road, Furong District, Changsha, Hunan, 410125, People's Republic of China.
Xi
X
Li
Key Laboratory of Agro-ecological Process in Subtropical Region, Changsha Research Station for Agricultural & Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Science, No. 644, the Second Yuanda Road, Furong District, Changsha, Hunan, 410125, People's Republic of China.
Pei
P
Luo
Key Laboratory of Agro-ecological Process in Subtropical Region, Changsha Research Station for Agricultural & Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Science, No. 644, the Second Yuanda Road, Furong District, Changsha, Hunan, 410125, People's Republic of China.
Run-Lin
RL
Xiao
Key Laboratory of Agro-ecological Process in Subtropical Region, Changsha Research Station for Agricultural & Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Science, No. 644, the Second Yuanda Road, Furong District, Changsha, Hunan, 410125, People's Republic of China.
Yong
Y
Li
Key Laboratory of Agro-ecological Process in Subtropical Region, Changsha Research Station for Agricultural & Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Science, No. 644, the Second Yuanda Road, Furong District, Changsha, Hunan, 410125, People's Republic of China.
Jin-Shui
JS
Wu
D064751:Ammonium Compounds / Q000378:metabolism*; D000693:Anaerobiosis; D000818:Animals; D001421:Bacteria, Anaerobic / Q000235:genetics* / Q000378:metabolism*; D044822:Biodiversity; D019015:Geologic Sediments / Q000382:microbiology; D059013:Microbial Consortia / Q000235:genetics / Q000502:physiology; D009584:Nitrogen / Q000378:metabolism; D010084:Oxidation-Reduction; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S; D060888:Real-Time Polymerase Chain Reaction; D012988:Soil Microbiology; D013552:Swine; D062065:Wastewater / Q000382:microbiology*; D053833:Wetlands
D064751:Ammonium Compounds; D009584:Nitrogen; D012336:RNA, Ribosomal, 16S; D062065:Wastewater
Anammox; Constructed wetlands; N removal; Phylogenetic analyses; Swine wastewater