气候变化领域集成服务门户(CCPortal): Assessing microbial residues in soil as a potential carbon sink and moderator of carbon use efficiency

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DOI	10.1007/s10533-020-00720-4
	Assessing microbial residues in soil as a potential carbon sink and moderator of carbon use efficiency
	Geyer K.; Schnecker J.; Grandy A.S.; Richter A.; Frey S.
发表日期	2020
ISSN	0168-2563
起始页码	237
结束页码	249
卷号	151 期号:2020-02-03
英文摘要	A longstanding assumption of glucose tracing experiments is that all glucose is microbially utilized during short incubations of ≤2 days to become microbial biomass or carbon dioxide. Carbon use efficiency (CUE) estimates have consequently ignored the formation of residues (non-living microbial products) although such materials could represent an important sink of glucose that is prone to stabilization as soil organic matter. We examined the dynamics of microbial residue formation from a short tracer experiment with frequent samplings over 72 h, and conducted a meta-analysis of previously published glucose tracing studies to assess the generality of these experimental results. Both our experiment and meta-analysis indicated 30–34% of amended glucose-C (13C or 14C) was in the form of residues within the first 6 h of substrate addition. We expand the conventional efficiency calculation to include residues in both the numerator and denominator of efficiency, thereby deriving a novel metric of the potential persistence of glucose-C in soil as living microbial biomass plus residues (‘carbon stabilization efficiency’). This new metric indicates nearly 40% of amended glucose-C persists in soil 180 days after amendment, the majority as non-biomass residues. Starting microbial biomass and clay content emerge as critical factors that positively promote such long term stabilization of labile C. Rapid residue production supports the conclusion that non-growth maintenance activity can illicit high demands for C in soil, perhaps equaling that directed towards growth, and that residues may have an underestimated role in the cycling and sequestration potential of C in soil. © 2020, The Author(s).
英文关键词	Carbon cycling; Carbon use efficiency; Isotopic glucose tracing; Microbial ecology; Microbial residues
语种	英语
来源期刊	Biogeochemistry
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/153082
作者单位	Department of Natural Resources and the Environment, University of New Hampshire, Durham, NH 03824, United States; Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, 1090, Austria; Department of Biology, Young Harris College, 1 College St, Young Harris, GA 30582, United States
推荐引用方式 GB/T 7714	Geyer K.,Schnecker J.,Grandy A.S.,et al. Assessing microbial residues in soil as a potential carbon sink and moderator of carbon use efficiency[J],2020,151(2020-02-03).
APA	Geyer K.,Schnecker J.,Grandy A.S.,Richter A.,&Frey S..(2020).Assessing microbial residues in soil as a potential carbon sink and moderator of carbon use efficiency.Biogeochemistry,151(2020-02-03).
MLA	Geyer K.,et al."Assessing microbial residues in soil as a potential carbon sink and moderator of carbon use efficiency".Biogeochemistry 151.2020-02-03(2020).