DOI: 10.1007/s10533-014-9954-5
Scopus记录号: 2-s2.0-84897421987
论文题名: Plant rhizosphere influence on microbial C metabolism: The role of elevated CO2, N availability and root stoichiometry
作者: Carrillo Y. ; Dijkstra F.A. ; Pendall E. ; LeCain D. ; Tucker C.
刊名: Biogeochemistry
ISSN: 0168-2563
EISSN: 1573-515X
出版年: 2014
卷: 117, 期: 2018-02-03 起始页码: 229
结束页码: 240
语种: 英语
英文关键词: Carbon
; Metabolic quotient
; Microbial communities
; Microbial efficiency
; Nitrogen
; Roots
; Soil organic matter
; Stoichiometry
英文摘要: Microbial decomposer C metabolism is considered a factor controlling soil C stability, a key regulator of global climate. The plant rhizosphere is now recognized as a crucial driver of soil C dynamics but specific mechanisms by which it can affect C processing are unclear. Climate change could affect microbial C metabolism via impacts on the plant rhizosphere. Using continuous 13C labelling under controlled conditions that allowed us to quantify SOM derived-C in all pools and fluxes, we evaluated the microbial metabolism of soil C in the rhizosphere of a C4 native grass exposed to elevated CO2 and under variation in N concentrations in soil and in plant root C:N stoichiometry. Our results demonstrated that this plant can influence soil C metabolism and further, that elevated CO2 conditions can alter this role by increasing microbial C efficiency as indicated by a reduction in soil-derived C respiration per unit of soil C-derived microbial biomass. Moreover, under elevated CO2 increases in soil N, and notably, root tissue N concentration increased C efficiency, suggesting elevated CO2 shifted the stoichiometric balance so N availability was a more critical factor regulating efficiency than under ambient conditions. The root C:N stoichiometry effect indicates that plant chemical traits such as root N concentration are able to influence the metabolism of soil C and that elevated CO2 conditions can modulate this role. Increased efficiency in soil C use was associated with negative rhizosphere priming and we hypothesize that the widely observed phenomenon of rhizosphere priming may result, at least in part, from changes in the metabolic efficiency of microbial populations. Observed changes in the microbial community support that shifting microbial populations were a contributing factor to the observed metabolic responses. Our case study points at greater efficiency of the SOM-degrading populations in a high CO2, high N world, potentially leading to greater C storage of microbially assimilated C in soil. © 2014 Springer International Publishing Switzerland. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/83622
Appears in Collections: 气候减缓与适应 气候变化事实与影响
There are no files associated with this item.
作者单位: Department of Botany and Program in Ecology, University of Wyoming, Laramie, WY, 82071, United States; Department of Environmental Sciences, Centre for Carbon, Water and Food, University of Sydney, 380 Werombi Rd, Camden, NSW, 2570, Australia; Crops Research Laboratory, USDA-ARS Rangeland Resources Research Unit, 1701 Center Ave, Fort Collins, CO, 80526, United States; Institute of Arctic Biology, University of Alaska, Fairbanks, AK, 99775, United States; Hawkesbury Institute for the Environment, University of Western Sydney, Locked Bag 1797, Penrith South DC, NSW, 2751, Australia
Recommended Citation:
Carrillo Y.,Dijkstra F.A.,Pendall E.,et al. Plant rhizosphere influence on microbial C metabolism: The role of elevated CO2, N availability and root stoichiometry[J]. Biogeochemistry,2014-01-01,117(2018-02-03)