title: Effect of simulated tillage on microbial autotrophic CO2 fixation in paddy and upland soils.
abstract: Tillage is a common agricultural practice affecting soil structure and biogeochemistry. To evaluate how tillage affects soil microbial CO2 fixation, we incubated and continuously labelled samples from two paddy soils and two upland soils subjected to simulated conventional tillage (CT) and no-tillage (NT) treatments. Results showed that CO2 fixation ((14)C-SOC) in CT soils was significantly higher than in NT soils. We also observed a significant, soil type- and depth-dependent effect of tillage on the incorporation rates of labelled C to the labile carbon pool. Concentrations of labelled C in the carbon pool significantly decreased with soil depth, irrespective of tillage. Additionally, quantitative PCR assays revealed that for most soils, total bacteria and cbbL-carrying bacteria were less abundant in CT versus NT treatments, and tended to decrease in abundance with increasing depth. However, specific CO2 fixation activity was significantly higher in CT than in NT soils, suggesting that the abundance of cbbL-containing bacteria may not always reflect their functional activity. This study highlights the positive effect of tillage on soil microbial CO2 fixation, and the results can be readily applied to the development of sustainable agricultural management.
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.|State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Jiangshu, 210008, China.
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.|Faculty of Life Science and Technology, Central South University of Forestry and Technology, Changsha, 410004, 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.|ISA-CAS and UWA Joint Laboratory for Soil Systems Biology, Hunan, 410125, China.
authors.forename: Qiong
authors.initials: Q
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: 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.
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.affiliation: ISA-CAS and UWA Joint Laboratory for Soil Systems Biology, Hunan, 410125, China.|School of Earth and Environment, The University of Western Australia, Crawley, WA 6009, Australia.
authors.forename: A S
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: D000704:Analysis of Variance; D052818:Autotrophic Processes; D001419:Bacteria / Q000235:genetics / Q000378:metabolism*; D018533:Biomass; D002244:Carbon / Q000032:analysis; D057486:Carbon Cycle; D002245:Carbon Dioxide / Q000378:metabolism*; D002250:Carbon Radioisotopes; D005798:Genes, Bacterial; D012275:Oryza / Q000502:physiology*; D012987:Soil / Q000737:chemistry*; D012988:Soil Microbiology; D012995:Solubility
chemical_list: D002250:Carbon Radioisotopes; D012987:Soil; D002245:Carbon Dioxide; D002244:Carbon