title: Sedimentary archaeal amoA gene abundance reflects historic nutrient level and salinity fluctuations in Qinghai Lake, Tibetan Plateau.
abstract: Integration of DNA derived from ancient phototrophs with their characteristic lipid biomarkers has been successfully employed to reconstruct paleoenvironmental conditions. However, it is poorly known that whether the DNA and lipids of microbial functional aerobes (such as ammonia-oxidizing archaea: AOA) can be used for reconstructing past environmental conditions. Here we identify and quantify the AOA amoA genes (encoding the alpha subunit of ammonia monooxygenases) preserved in a 5.8-m sediment core (spanning the last 18,500 years) from Qinghai Lake. Parallel analyses revealed that low amoA gene abundance corresponded to high total organic carbon (TOC) and salinity, while high amoA gene abundance corresponded to low TOC and salinity. In the Qinghai Lake region, TOC can serve as an indicator of paleo-productivity and paleo-precipitation, which is related to historic nutrient input and salinity. So our data suggest that temporal variation of AOA amoA gene abundance preserved in Qinghai Lake sediment may reflect the variations of nutrient level and salinity throughout the late Pleistocene and Holocene in the Qinghai Lake region.
authors.affiliation: State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, 430074, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, 430074, China.
authors.forename: Hongchen
authors.initials: H
authors.lastname: Jiang
authors.affiliation: State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Beijing, 100083, China.|Department of Geology and Environmental Earth Science, Miami University, Oxford, OH45056, USA.
authors.forename: Hailiang
authors.initials: H
authors.lastname: Dong
authors.affiliation: State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Beijing, 100083, China.
authors.forename: Weiguo
authors.initials: W
authors.lastname: Hou
authors.affiliation: State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Beijing, 100083, China.
authors.forename: Gaoyuan
authors.initials: G
authors.lastname: Li
authors.affiliation: State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, 430074, China.
authors.forename: Geng
authors.initials: G
authors.lastname: Wu
mesh_terms: D000641:Ammonia; D001105:Archaea / Q000145:classification / Q000201:enzymology / Q000235:genetics*; D019843:Archaeal Proteins / Q000235:genetics* / Q000378:metabolism; D002244:Carbon / Q000378:metabolism; D017753:Ecosystem; D005843:Geography; D019015:Geologic Sediments / Q000382:microbiology*; D060106:Lakes / Q000737:chemistry / Q000382:microbiology*; D010088:Oxidoreductases / Q000235:genetics* / Q000378:metabolism; D010802:Phylogeny; D019642:RNA, Archaeal / Q000235:genetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D055110:Radiometric Dating / Q000379:methods; D054712:Salinity; D018609:Tibet; D013997:Time Factors
chemical_list: D019843:Archaeal Proteins; D019642:RNA, Archaeal; D012336:RNA, Ribosomal, 16S; D002244:Carbon; D000641:Ammonia; D010088:Oxidoreductases; C045582:ammonia monooxygenase