title: Variability in responses of bacterial communities and nitrogen oxide emission to urea fertilization among various flooded paddy soils.
abstract: Fertilization affects bacterial communities and element biogeochemical cycling in flooded paddy soils and the effect might differ among soil types. In this study, five paddy soils from Southern China were subjected to urea addition to explore impacts of fertilization on nitrogen oxide (N2O) emission and bacterial community composition under the flooding condition. 16S rRNA gene-based illumina sequencing showed no obvious shifts in bacterial community composition of five soils after urea addition. However, some genera were affected by fertilization addition and the influenced genera varied among soils. During the late period (day 8-19) of flooding incubation without urea addition, N2O emission rates were elevated for all soils. However, urea effects on N2O emission were different among flooded soils. For soils where nirS and nirK gene abundances increased with urea addition, N2O emission was significantly increased compared to control treatment. Redundancy analysis showed that dissolved organic carbon, ammonium (NH4 (+)), ferrous iron (Fe(2+)) and nitrate (NO3 (-)) in pore water explained 33.4% of the variation in soil bacterial community composition, implying that urea regimes influenced the relative abundance of some bacterial populations possibly by regulating soil characteristics and then influencing N2O emission. These results provided insights into soil type-dependent effect of fertilization on the overall bacterial communities and nitrogen oxide emission in flooded paddy soils.
authors.affiliation: State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Ning
authors.initials: N
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Long-Jun
authors.initials: LJ
authors.lastname: Ding
authors.affiliation: University of Chinese Academy of Sciences, Beijing 100049, China Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.
authors.forename: Hui-Juan
authors.initials: HJ
authors.lastname: Xu
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210046, China.
authors.forename: Hong-Bo
authors.initials: HB
authors.lastname: Li
authors.affiliation: Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China jqsu@iue.ac.cn.
authors.forename: Jian-Qiang
authors.initials: JQ
authors.lastname: Su
authors.affiliation: State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.
authors.forename: Yong-Guan
authors.initials: YG
authors.lastname: Zhu
mesh_terms: D001483:Base Sequence; D002681:China; D004269:DNA, Bacterial / Q000235:genetics; D005308:Fertilizers; D055868:Floods; D064307:Microbiota / Q000502:physiology*; D050901:Nitrate Reductase / Q000235:genetics; D009566:Nitrates / Q000032:analysis; D009609:Nitrous Oxide / Q000032:analysis / Q000378:metabolism*; D012336:RNA, Ribosomal, 16S; D017422:Sequence Analysis, DNA; D012987:Soil / Q000737:chemistry*; D012988:Soil Microbiology; D014508:Urea / Q000378:metabolism*; D014867:Water / Q000032:analysis
chemical_list: D004269:DNA, Bacterial; D005308:Fertilizers; D009566:Nitrates; D012336:RNA, Ribosomal, 16S; D012987:Soil; D014867:Water; D014508:Urea; D050901:Nitrate Reductase; D009609:Nitrous Oxide
keywords: bacterial population; functional gene; nitrous oxide; urea