DOI: 10.1002/2015GB005302
Scopus记录号: 2-s2.0-84970024740
论文题名: Topographic variability and the influence of soil erosion on the carbon cycle
作者: Dialynas Y ; G ; , Bastola S ; , Bras R ; L ; , Billings S ; A ; , Markewitz D ; , Richter D ; D
刊名: Global Biogeochemical Cycles
ISSN: 8866236
出版年: 2016
卷: 30, 期: 5 起始页码: 644
结束页码: 660
语种: 英语
英文关键词: atmospheric CO2
; carbon replacement
; episodic erosion
; soil organic carbon
; spatially explicit model
; tRIBS
Scopus关键词: agricultural soil
; carbon cycle
; episodic event
; global change
; heterogeneity
; net ecosystem exchange
; real time
; soil erosion
; soil organic matter
; spatiotemporal analysis
; topography
; South Carolina
; United States
英文摘要: Soil erosion, particularly that caused by agriculture, is closely linked to the global carbon (C) cycle. There is a wide range of contrasting global estimates of how erosion alters soil-atmosphere C exchange. This can be partly attributed to limited understanding of how geomorphology, topography, and management practices affect erosion and oxidation of soil organic C (SOC). This work presents a physically based approach that stresses the heterogeneity at fine spatial scales of SOC erosion, SOC burial, and associated soil-atmosphere C fluxes. The Holcombe's Branch watershed, part of the Calhoun Critical Zone Observatory in South Carolina, USA, is the case study used. The site has experienced some of the most serious agricultural soil erosion in North America. We use SOC content measurements from contrasting soil profiles and estimates of SOC oxidation rates at multiple soil depths. The methodology was implemented in the tRIBS-ECO (Triangulated Irregular Network-based Real-time Integrated Basin Simulator-Erosion and Carbon Oxidation), a spatially and depth-explicit model of SOC dynamics built within an existing coupled physically based hydro-geomorphic model. According to observations from multiple soil profiles, about 32% of the original SOC content has been eroded in the study area. The results indicate that C erosion and its replacement exhibit significant topographic variation at relatively small scales (tens of meters). The episodic representation of SOC erosion reproduces the history of SOC erosion better than models that use an assumption of constant erosion in space and time. The net atmospheric C exchange at the study site is estimated to range from a maximum source of 14.5 g m−2 yr−1 to a maximum sink of −18.2 g m−2 yr−1. The small-scale complexity of C erosion and burial driven by topography exerts a strong control on the landscape's capacity to serve as a C source or a sink. ©2016. American Geophysical Union. All Rights Reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/77858
Appears in Collections: 气候变化事实与影响
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作者单位: School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA, United States; School of Civil and Environmental Engineering and School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA, United States; Department of Ecology and Evolutionary Biology and Kansas Biological Survey, University of Kansas, Lawrence, KS, United States; Warnell School of Forest Resources, University of Georgia, Athens, GA, United States; Nicholas School of the Environment and Earth Sciences, Duke University, Durham, NC, United States
Recommended Citation:
Dialynas Y,G,, Bastola S,et al. Topographic variability and the influence of soil erosion on the carbon cycle[J]. Global Biogeochemical Cycles,2016-01-01,30(5)