气候变化领域集成服务门户(CCPortal): Microbial formation of stable soil carbon is more efficient from belowground than aboveground input

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DOI	10.1038/s41561-018-0258-6
	Microbial formation of stable soil carbon is more efficient from belowground than aboveground input
	Sokol N.W.; Bradford M.A.
发表日期	2019
ISSN	17520894
卷号	12 期号:1
英文摘要	The relative contributions of aboveground versus belowground plant carbon inputs to the stable soil organic carbon pool are the subject of much debate—with direct implications for how the carbon cycle is modelled and managed. The belowground rhizosphere pathway (that is, carbon exiting the living root) is theorized to form stable soil carbon more efficiently than the aboveground pathway. However, while several mechanisms have been invoked to explain this efficiency, few have been empirically tested or quantified. Here, we use soil microcosms with standardized carbon inputs to investigate three posited mechanisms that differentiate aboveground from belowground input pathways of dissolved organic carbon—through the microbial biomass—to the mineral-stabilized soil organic carbon pool: (1) the physical distance travelled, (2) the microbial abundance in the region in which a carbon compound enters (that is, rhizosphere versus bulk soil) and (3) the frequency and volume of carbon delivery (that is, infrequent ‘pulse’ versus frequent ‘drip’). We demonstrate that through the microbial formation pathway, belowground inputs form mineral-stabilized soil carbon more efficiently than aboveground inputs, partly due to the greater efficiency of formation by the rhizosphere microbial community relative to the bulk soil community. However, we show that because the bulk soil has greater capacity to form mineral-stabilized soil carbon due to its greater overall volume, the relative contributions of aboveground versus belowground carbon inputs depend strongly on the ratio of rhizosphere to bulk soil. © 2018, The Author(s), under exclusive licence to Springer Nature Limited.
语种	英语
scopus关键词	biomass; carbon cycle; microbial activity; microbial community; microcosm; organic carbon; rhizosphere; soil carbon; soil stabilization
来源期刊	Nature Geoscience
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/124744
作者单位	Yale University, School of Forestry & Environmental Studies, New Haven, CT, United States; Lawrence Livermore National Laboratory, Physical and Life Sciences Directorate, Livermore, CA, United States
推荐引用方式 GB/T 7714	Sokol N.W.,Bradford M.A.. Microbial formation of stable soil carbon is more efficient from belowground than aboveground input[J],2019,12(1).
APA	Sokol N.W.,&Bradford M.A..(2019).Microbial formation of stable soil carbon is more efficient from belowground than aboveground input.Nature Geoscience,12(1).
MLA	Sokol N.W.,et al."Microbial formation of stable soil carbon is more efficient from belowground than aboveground input".Nature Geoscience 12.1(2019).