Depthwise Soil CO2 Production Is Controlled by Freeze-Thaw Processes in a Tibetan Alpine Steppe

doi:10.1029/2021JG006678

CORC > 成都山地灾害与环境研究所 > 中国科学院水利部成都山地灾害与环境研究所 > 山地表生过程与生态调控重点实验室

	Depthwise Soil CO2 Production Is Controlled by Freeze-Thaw Processes in a Tibetan Alpine Steppe
	Zhang, Jianxin 1,2; Wei, Da 2; Hong, Jiangtao 2; Wang, Xiaodan 2
刊名	JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES
	2022
卷号	127 期号:1 页码:15
关键词	Soil CO2 production freeze-thaw processes Tibetan Plateau alpine steppe
ISSN号	2169-8953
DOI	10.1029/2021JG006678
通讯作者	Wang, Xiaodan(wxd@imde.ac.cn)
英文摘要	Cold ecosystems in regions of high-latitude and altitude with vast stores of soil organic carbon suffer strong freeze-thaw cycles, which can greatly affect soil CO2 release. However, on the Tibetan Plateau, where altitude is >4,000 m, it remains unknown how freeze-thaw processes regulate CO2 production across the soil profile. In this study, we used the gradient method to explore impacts of freeze-thaw processes on depthwise soil CO2 production in an alpine steppe. We found almost all soil CO2 was produced in the root-zone layer (<30 cm), while the root-free layer (>30 cm) frequently alternated between being a source and sink of CO2 and thus acted largely as a buffer. The surface layer (0-15 cm) and subsurface layer (15-30 cm) had a similar CO2 production rate in the thawed period. However, during the freezing-frozen-thawing period, the subsurface layer consistently functioned as a weak CO2 source, although parts were trapped in frozen soil, resulting in a weaker CO2 sink in the surface layer. Soil CO2 production in subsurface layer is thus more sensitive to temperature variability compared with surface layer. Furthermore, our results suggest water content plays a more important role than temperature in regulating soil CO2 production. For the first time, our data set reveals the vertical production of CO2 within the seasonally frozen soils on the Tibetan Plateau, which will benefit understanding of belowground carbon processes and modeling of soil CO2 release in the region.
资助项目	Second Tibetan Plateau Scientific Expedition and Research Program (STEP)[2019QZKK0404] ; Strategic Priority Research Program of Chinese Academy of Sciences[XDA20020401] ; Youth Innovation Promotion Association of the Chinese Academy of Sciences[2020369]
WOS关键词	CARBON-DIOXIDE ; TEMPERATURE SENSITIVITY ; WATER-CONTENT ; VERTICAL-DISTRIBUTION ; MICROBIAL ACTIVITY ; PERMAFROST CARBON ; GRADIENT-METHOD ; ORGANIC-MATTER ; GAS-DIFFUSION ; FROZEN SOIL
WOS研究方向	Environmental Sciences & Ecology ; Geology
语种	英语
出版者	AMER GEOPHYSICAL UNION
WOS记录号	WOS:000751889000014
资助机构	Second Tibetan Plateau Scientific Expedition and Research Program (STEP) ; Strategic Priority Research Program of Chinese Academy of Sciences ; Youth Innovation Promotion Association of the Chinese Academy of Sciences
内容类型	期刊论文
源URL	[http://ir.imde.ac.cn/handle/131551/56432]
专题	成都山地灾害与环境研究所_山地表生过程与生态调控重点实验室
通讯作者	Wang, Xiaodan
作者单位	1.Univ Chinese Acad Sci, Beijing, Peoples R China 2.Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu, Peoples R China
推荐引用方式 GB/T 7714	Zhang, Jianxin,Wei, Da,Hong, Jiangtao,et al. Depthwise Soil CO2 Production Is Controlled by Freeze-Thaw Processes in a Tibetan Alpine Steppe[J]. JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES,2022,127(1):15.
APA	Zhang, Jianxin,Wei, Da,Hong, Jiangtao,&Wang, Xiaodan.(2022).Depthwise Soil CO2 Production Is Controlled by Freeze-Thaw Processes in a Tibetan Alpine Steppe.JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES,127(1),15.
MLA	Zhang, Jianxin,et al."Depthwise Soil CO2 Production Is Controlled by Freeze-Thaw Processes in a Tibetan Alpine Steppe".JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES 127.1(2022):15.