气候变化领域集成服务门户(CCPortal): Elevated atmospheric CO2 drives decreases in stable soil organic carbon in arid ecosystems: Evidence from a physical fractionation and organic compound analysis

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DOI	10.1111/gcb.17175
	Elevated atmospheric CO2 drives decreases in stable soil organic carbon in arid ecosystems: Evidence from a physical fractionation and organic compound analysis
	Jensen, Kelsey H.; Grandy, A. Stuart; Sparks, Jed P.
发表日期	2024
ISSN	1354-1013
EISSN	1365-2486
起始页码	30
结束页码	2
卷号	30 期号:2
英文摘要	The increasing concentration of CO2 in the atmosphere is perturbing the global carbon (C) cycle, altering stocks of organic C, including soil organic matter (SOM). The effect of this disturbance on soils in arid ecosystems may differ from other ecosystems due to water limitation. In this study, we conducted a density fractionation on soils previously harvested from the Nevada Desert FACE Facility (NDFF) to understand how elevated atmospheric CO2 (eCO(2)) affects SOM stability. Soils from beneath the perennial shrub, Larrea tridentata, and from unvegetated interspace were subjected to a sodium polytungstate density fractionation to separate light, particulate organic matter (POM, <1.85 g/cm(3)) from heavier, mineral associated organic matter (MAOM, >1.85 g/cm(3)). These fractions were analyzed for organic C, total N, delta C-13 and delta N-15, to understand the mechanisms behind changes. The heavy fraction was further analyzed by pyrolysis GC/MS to assess changes in organic compound composition. Elevated CO2 decreased POM-C and MAOM-C in soils beneath L. tridentata while interspace soils exhibited only a small increase in MAOM-N. Analysis of delta C-13 revealed incorporation of new C into both POM and MAOM pools indicating eCO(2) stimulated rapid turnover of both POM and MAOM. The largest losses of POM-C and MAOM-C observed under eCO(2) occurred in soils 20-40 cm in depth, highlighting that belowground C inputs may be a significant driver of SOM decomposition in this ecosystem. Pyrolysis GC/MS analysis revealed a decrease in organic compound diversity in the MAOM fraction of L. tridentata soils, becoming more similar to interspace soils under eCO(2). These results provide further evidence that MAOM stability may be compromised under disturbance and that SOC stocks in arid ecosystems are vulnerable under continued climate change.
英文关键词	carbon cycle; density fractionation; global change; nitrogen cycle; pyrolysis GC/MS; soil carbon; stable isotopes
语种	英语
WOS研究方向	Biodiversity & Conservation ; Environmental Sciences & Ecology
WOS类目	Biodiversity Conservation ; Ecology ; Environmental Sciences
WOS记录号	WOS:001160944100001
来源期刊	GLOBAL CHANGE BIOLOGY
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/304438
作者单位	Cornell University; University System Of New Hampshire; University of New Hampshire; Cornell University
推荐引用方式 GB/T 7714	Jensen, Kelsey H.,Grandy, A. Stuart,Sparks, Jed P.. Elevated atmospheric CO2 drives decreases in stable soil organic carbon in arid ecosystems: Evidence from a physical fractionation and organic compound analysis[J],2024,30(2).
APA	Jensen, Kelsey H.,Grandy, A. Stuart,&Sparks, Jed P..(2024).Elevated atmospheric CO2 drives decreases in stable soil organic carbon in arid ecosystems: Evidence from a physical fractionation and organic compound analysis.GLOBAL CHANGE BIOLOGY,30(2).
MLA	Jensen, Kelsey H.,et al."Elevated atmospheric CO2 drives decreases in stable soil organic carbon in arid ecosystems: Evidence from a physical fractionation and organic compound analysis".GLOBAL CHANGE BIOLOGY 30.2(2024).