气候变化领域集成服务门户(CCPortal): Mechanistic Modeling of Microtopographic Impacts on CO2 and CH4 Fluxes in an Alaskan Tundra Ecosystem Using the CLM-Microbe Model

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DOI	10.1029/2019MS001771
	Mechanistic Modeling of Microtopographic Impacts on CO2 and CH4 Fluxes in an Alaskan Tundra Ecosystem Using the CLM-Microbe Model
	Wang Y.; Yuan F.; Yuan F.; Gu B.; Hahn M.S.; Torn M.S.; Ricciuto D.M.; Kumar J.; He L.; Zona D.; Lipson D.A.; Wagner R.; Oechel W.C.; Wullschleger S.D.; Thornton P.E.; Xu X.
发表日期	2019
ISSN	19422466
起始页码	4288
结束页码	4304
卷号	11 期号:12
英文摘要	Spatial heterogeneities in soil hydrology have been confirmed as a key control on CO2 and CH4 fluxes in the Arctic tundra ecosystem. In this study, we applied a mechanistic ecosystem model, CLM-Microbe, to examine the microtopographic impacts on CO2 and CH4 fluxes across seven landscape types in Utqiaġvik, Alaska: trough, low-centered polygon (LCP) center, LCP transition, LCP rim, high-centered polygon (HCP) center, HCP transition, and HCP rim. We first validated the CLM-Microbe model against static-chamber measured CO2 and CH4 fluxes in 2013 for three landscape types: trough, LCP center, and LCP rim. Model application showed that low-elevation and thus wetter landscape types (i.e., trough, transitions, and LCP center) had larger CH4 emissions rates with greater seasonal variations than high-elevation and drier landscape types (rims and HCP center). Sensitivity analysis indicated that substrate availability for methanogenesis (acetate, CO2 + H2) is the most important factor determining CH4 emission, and vegetation physiological properties largely affect the net ecosystem carbon exchange and ecosystem respiration in Arctic tundra ecosystems. Modeled CH4 emissions for different microtopographic features were upscaled to the eddy covariance (EC) domain with an area-weighted approach before validation against EC-measured CH4 fluxes. The model underestimated the EC-measured CH4 flux by 20% and 25% at daily and hourly time steps, suggesting the importance of the time step in reporting CH4 flux. The strong microtopographic impacts on CO2 and CH4 fluxes call for a model-data integration framework for better understanding and predicting carbon flux in the highly heterogeneous Arctic landscape. ©2019. The Authors.
英文关键词	Arctic tundra; CH4 flux; microtopographic; net carbon exchange; sensitivity analysis
语种	英语
scopus关键词	Bacteria; Carbon; Carbon dioxide; Data integration; Forestry; Landforms; Sensitivity analysis; Arctic tundra; CH4 flux; Integration frameworks; microtopographic; Net carbon exchanges; Physiological properties; Spatial heterogeneity; Substrate availabilities; Ecosystems; carbon dioxide; carbon flux; eddy covariance; landscape; methane; modeling; net ecosystem exchange; seasonal variation; sensitivity analysis; soil-vegetation interaction; tundra; Alaska; Arctic; United States
来源期刊	Journal of Advances in Modeling Earth Systems
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/156802
作者单位	Department of Biology, San Diego State University, San Diego, CA, United States; Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States; Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang City, China; Civil and Environmental Engineering, University of California, Berkeley, Berkeley, CA, United States; Earth Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
推荐引用方式 GB/T 7714	Wang Y.,Yuan F.,Yuan F.,et al. Mechanistic Modeling of Microtopographic Impacts on CO2 and CH4 Fluxes in an Alaskan Tundra Ecosystem Using the CLM-Microbe Model[J],2019,11(12).
APA	Wang Y..,Yuan F..,Yuan F..,Gu B..,Hahn M.S..,...&Xu X..(2019).Mechanistic Modeling of Microtopographic Impacts on CO2 and CH4 Fluxes in an Alaskan Tundra Ecosystem Using the CLM-Microbe Model.Journal of Advances in Modeling Earth Systems,11(12).
MLA	Wang Y.,et al."Mechanistic Modeling of Microtopographic Impacts on CO2 and CH4 Fluxes in an Alaskan Tundra Ecosystem Using the CLM-Microbe Model".Journal of Advances in Modeling Earth Systems 11.12(2019).