title: Abundance and Diversity of Aerobic/Anaerobic Ammonia/Ammonium-Oxidizing Microorganisms in an Ammonium-Rich Aquitard in the Pearl River Delta of South China.
abstract: Natural occurring groundwater with abnormally high ammonium concentrations was discovered in the aquifer-aquitard system in the Pearl River Delta, South China. The community composition and abundance of aerobic/anaerobic ammonia/ammonium-oxidizing microorganisms (AOM) in the aquitard were investigated in this study. The alpha subunit of ammonia monooxygenase gene (amoA) was used as the biomarker for the detection of aerobic ammonia-oxidizing archaea (AOA) and bacteria (AOB), and also partial 16S rRNA gene for Plantomycetes and anaerobic ammonium-oxidizing (anammox) bacteria. Phylogenetic analysis showed that AOA in this aquitard were affiliated with those from water columns and wastewater treatment plants; and AOB were dominated by sequences among the Nitrosomonas marina/Nitrosomonas oligotropha lineage, which were affiliated with environmental sequences from coastal eutrophic bay and subtropical estuary. The richness and diversity of both AOA and AOB communities had very little variations with the depth. Candidatus Scalindua-related sequences dominated the anammox bacterial community. AOB amoA gene abundances were always higher than those of AOA at different depths in this aquitard. The Pearson moment correlation analysis showed that AOA amoA gene abundance positively correlated with pH and ammonium concentration, whereas AOB amoA gene abundance negatively correlated with C/N ratio. This is the first report that highlights the presence with low diversity of AOM communities in natural aquitard of rich ammonium.
authors.affiliation: School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, People's Republic of China.
authors.forename: Kwok-Ho
authors.initials: KH
authors.lastname: Lee
authors.affiliation: Guangdong Provincial Key Laboratory of Bio-control for the Forest Disease and Pest, Guangdong Academy of Forestry, No. 233 Guangshan 1st Road, Guangzhou, People's Republic of China.
authors.forename: Yong-Feng
authors.initials: YF
authors.lastname: Wang
authors.affiliation: School of Earth Science and Geological Engineering, Sun Yat-sen University, Guangzhou, 510275, People's Republic of China.
authors.forename: Ya
authors.initials: Y
authors.lastname: Wang
authors.affiliation: School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, People's Republic of China. jdgu@hku.hk.
authors.forename: Ji-Dong
authors.identifier: http://orcid.org/0000-0002-7082-9784
authors.initials: JD
authors.lastname: Gu
authors.affiliation: Department of Earth Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, People's Republic of China.
authors.forename: Jiu Jimmy
authors.initials: JJ
authors.lastname: Jiao
mesh_terms: D000332:Aerobiosis; D000641:Ammonia / Q000378:metabolism*; D064751:Ammonium Compounds / Q000378:metabolism*; D000693:Anaerobiosis; D001105:Archaea / Q000145:classification / Q000235:genetics / Q000378:metabolism; D001419:Bacteria / Q000145:classification* / Q000235:genetics / Q000378:metabolism*; D044822:Biodiversity; D002681:China; D019641:DNA, Archaeal / Q000235:genetics / Q000302:isolation & purification; D004269:DNA, Bacterial / Q000235:genetics / Q000302:isolation & purification; D063366:Estuaries; D005798:Genes, Bacterial / Q000235:genetics; D019015:Geologic Sediments / Q000737:chemistry / Q000382:microbiology; D006863:Hydrogen-Ion Concentration; D064307:Microbiota / Q000235:genetics / Q000502:physiology; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000235:genetics; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D045483:Rivers / Q000382:microbiology*; D012988:Soil Microbiology; D062065:Wastewater
chemical_list: D000641:Ammonia; D064751:Ammonium Compounds; D019641:DNA, Archaeal; D004269:DNA, Bacterial; D010088:Oxidoreductases; D012336:RNA, Ribosomal, 16S; D062065:Wastewater; C045582:ammonia monooxygenase
keywords: Ammonia-oxidizing archaea; Ammonia-oxidizing bacteria; Anammox; Aquitard; Pearl River Delta Estuary