title: Soil microbial community composition and respiration along an experimental precipitation gradient in a semiarid steppe.
abstract: As a primary limiting factor in arid and semiarid regions, precipitation strongly influences soil microbial properties. However, the patterns and mechanisms of soil microbial responses to precipitation have not been well documented. In this study, changes in soil microorganisms along an experimental precipitation gradient with seven levels of precipitation manipulation (i.e., ambient precipitation as a control, and ±20%, ±40%, and ±60% of ambient precipitation) were explored in a semiarid temperate steppe in northern China. Soil microbial biomass carbon and respiration as well as the ratio of fungal to bacterial biomass varied along the experimental precipitation gradient and peaked under the +40% precipitation treatment. The shifts in microbial community composition could be largely attributable to the changes in soil water and nutrient availability. The metabolic quotient increased (indicating reduced carbon use efficiency) with increasing precipitation due to the leaching of dissolved organic carbon. The relative contributions of microbial respiration to soil and ecosystem respiration increased with increasing precipitation, suggesting that heterotrophic respiration will be more sensitive than autotrophic respiration if precipitation increases in the temperate steppe as predicted under future climate-change scenarios.
authors.affiliation: State Key Laboratory of Cotton Biology, Key Laboratory of Plant Stress Biology, College of Life Sciences, Henan University, Kaifeng, Henan 475004, China.
authors.forename: Cancan
authors.initials: C
authors.lastname: Zhao
authors.affiliation: State Key Laboratory of Cotton Biology, Key Laboratory of Plant Stress Biology, College of Life Sciences, Henan University, Kaifeng, Henan 475004, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Miao
authors.affiliation: State Key Laboratory of Cotton Biology, Key Laboratory of Plant Stress Biology, College of Life Sciences, Henan University, Kaifeng, Henan 475004, China.
authors.forename: Chengde
authors.initials: C
authors.lastname: Yu
authors.affiliation: State Key Laboratory of Cotton Biology, Key Laboratory of Plant Stress Biology, College of Life Sciences, Henan University, Kaifeng, Henan 475004, China.
authors.forename: Lili
authors.initials: L
authors.lastname: Zhu
authors.affiliation: State Key Laboratory of Cotton Biology, Key Laboratory of Plant Stress Biology, College of Life Sciences, Henan University, Kaifeng, Henan 475004, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Cotton Biology, Key Laboratory of Plant Stress Biology, College of Life Sciences, Henan University, Kaifeng, Henan 475004, China.|School of Biology, Georgia Institute of Technology, Atlanta, GA 30332, USA.
authors.forename: Lin
authors.initials: L
authors.lastname: Jiang
authors.affiliation: State Key Laboratory of Cotton Biology, Key Laboratory of Plant Stress Biology, College of Life Sciences, Henan University, Kaifeng, Henan 475004, China.|Department of Biological Sciences, Tennessee State University, Nashville, TN 37209, USA.
authors.forename: Dafeng
authors.initials: D
authors.lastname: Hui
authors.affiliation: State Key Laboratory of Cotton Biology, Key Laboratory of Plant Stress Biology, College of Life Sciences, Henan University, Kaifeng, Henan 475004, China.
authors.forename: Shiqiang
authors.initials: S
authors.lastname: Wan
mesh_terms: D001419:Bacteria / Q000145:classification / Q000302:isolation & purification; D058448:Biota; D002244:Carbon / Q000378:metabolism; D002681:China; D003889:Desert Climate; D004734:Energy Metabolism; D005658:Fungi / Q000145:classification / Q000302:isolation & purification; D065948:Grassland; D011891:Rain; D012988:Soil Microbiology
chemical_list: D002244:Carbon