title: Abundance and Diversity of CO2-Assimilating Bacteria and Algae Within Red Agricultural Soils Are Modulated by Changing Management Practice.
abstract: Elucidating the biodiversity of CO(2)-assimilating bacterial and algal communities in soils is important for obtaining a mechanistic view of terrestrial carbon sinks operating at global scales. "Red" acidic soils (Orthic Acrisols) cover large geographic areas and are subject to a range of management practices, which may alter the balance between carbon dioxide production and assimilation through changes in microbial CO(2)-assimilating populations. Here, we determined the abundance and diversity of CO(2)-assimilating bacteria and algae in acidic soils using quantitative PCR and terminal restriction fragment length polymorphism (T-RFLP) of the cbbL gene, which encodes the key CO(2) assimilation enzyme (ribulose-1,5-bisphosphate carboxylase/oxygenase) in the Calvin cycle. Within the framework of a long-term experiment (Taoyuan Agro-ecosystem, subtropical China), paddy rice fields were converted in 1995 to four alternative land management regimes: natural forest (NF), paddy rice (PR), maize crops (CL), and tea plantations (TP). In 2012 (17 years after land use transformation), we collected and analyzed the soils from fields under the original and converted land management regimes. Our results indicated that fields under the PR soil management system harbored the greatest abundance of cbbL copies (4.33 × 10(8) copies g(-1) soil). More than a decade after converting PR soils to natural, rotation, and perennial management systems, a decline in both the diversity and abundance of cbbL-harboring bacteria and algae was recorded. The lowest abundance of bacteria (0.98 × 10(8) copies g(-1) soil) and algae (0.23 × 10(6) copies g(-1) soil) was observed for TP soils. When converting PR soil management to alternative management systems (i.e., NF, CL, and TP), soil edaphic factors (soil organic carbon and total nitrogen content) were the major determinants of bacterial autotrophic cbbL gene diversity. In contrast, soil phosphorus concentration was the major regulator of algal cbbL community composition. Our results provide new insights into the diversity, abundance, and modulation of organisms responsible for microbial autotrophic CO(2) fixation in red acidic soils subjected to changing management regimes.
authors.affiliation: Changsha Research Station for Agricultural and Environmental Monitoring & Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Hunan, 410125, China.|ISA-CAS and UWA Joint Laboratory for Soil Systems Biology, Hunan, 410125, China.
authors.forename: Hongzhao
authors.initials: H
authors.lastname: Yuan
authors.affiliation: Changsha Research Station for Agricultural and Environmental Monitoring & Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Hunan, 410125, China. gtd@isa.ac.cn.|ISA-CAS and UWA Joint Laboratory for Soil Systems Biology, Hunan, 410125, China. gtd@isa.ac.cn.
authors.forename: Tida
authors.initials: T
authors.lastname: Ge
authors.affiliation: Changsha Research Station for Agricultural and Environmental Monitoring & Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Hunan, 410125, China.
authors.forename: Xiangbi
authors.initials: X
authors.lastname: Chen
authors.affiliation: Changsha Research Station for Agricultural and Environmental Monitoring & Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Hunan, 410125, China.
authors.forename: Shoulong
authors.initials: S
authors.lastname: Liu
authors.affiliation: Changsha Research Station for Agricultural and Environmental Monitoring & Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Hunan, 410125, China.|ISA-CAS and UWA Joint Laboratory for Soil Systems Biology, Hunan, 410125, China.
authors.forename: Zhenke
authors.initials: Z
authors.lastname: Zhu
authors.affiliation: Changsha Research Station for Agricultural and Environmental Monitoring & Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Hunan, 410125, China.|ISA-CAS and UWA Joint Laboratory for Soil Systems Biology, Hunan, 410125, China.
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Wu
authors.affiliation: Changsha Research Station for Agricultural and Environmental Monitoring & Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Hunan, 410125, China.|Taoyuan Agro-ecosystem Research Station, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, 410125, China.
authors.forename: Wenxue
authors.initials: W
authors.lastname: Wei
authors.affiliation: ISA-CAS and UWA Joint Laboratory for Soil Systems Biology, Hunan, 410125, China.|School of Earth & Environment, The University of Western Australia, Crawley, Perth, WA, 6009, Australia.
authors.forename: Andrew Steven
authors.initials: AS
authors.lastname: Whiteley
authors.affiliation: Changsha Research Station for Agricultural and Environmental Monitoring & Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Hunan, 410125, China.|ISA-CAS and UWA Joint Laboratory for Soil Systems Biology, Hunan, 410125, China.
authors.forename: Jinshui
authors.initials: J
authors.lastname: Wu
mesh_terms: D000383:Agriculture / Q000379:methods*; D001419:Bacteria / Q000145:classification* / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D057486:Carbon Cycle; D002245:Carbon Dioxide / Q000378:metabolism*; D002681:China; D048028:DNA, Algal / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics; D017753:Ecosystem; D014644:Genetic Variation; D006863:Hydrogen-Ion Concentration; D009584:Nitrogen / Q000032:analysis; D012275:Oryza / Q000382:microbiology; D010758:Phosphorus / Q000032:analysis; D010802:Phylogeny; D010839:Phytoplankton / Q000145:classification* / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D012150:Polymorphism, Restriction Fragment Length; D012273:Ribulose-Bisphosphate Carboxylase / Q000235:genetics / Q000378:metabolism; D012987:Soil / Q000737:chemistry*; D012988:Soil Microbiology
chemical_list: D048028:DNA, Algal; D004269:DNA, Bacterial; D012987:Soil; D002245:Carbon Dioxide; D010758:Phosphorus; D012273:Ribulose-Bisphosphate Carboxylase; D009584:Nitrogen
keywords: Algae; CO2-assimilating bacteria; Land management; Red acidic soil; cbbL gene