DOI: 10.1016/j.atmosenv.2017.05.036
Scopus记录号: 2-s2.0-85019978885
论文题名: Abiotic and seasonal control of soil-produced CO2 efflux in karstic ecosystems located in Oceanic and Mediterranean climates
作者: Garcia-Anton E ; , Cuezva S ; , Fernandez-Cortes A ; , Alvarez-Gallego M ; , Pla C ; , Benavente D ; , Cañaveras J ; C ; , Sanchez-Moral S
刊名: Atmospheric Environment
ISSN: 0168-2563
EISSN: 1573-515X
出版年: 2017
卷: 164 起始页码: 31
结束页码: 49
语种: 英语
英文关键词: Climatic control
; CO2 exchange
; Soil CO2 diffusion
; Vadose zone
; δ13CO2
Scopus关键词: Atmospheric composition
; Carbon dioxide
; Caves
; Diffusion
; Drought
; Isotopes
; Soil moisture
; Soils
; Climatic controls
; Geomorphologic features
; Mediterranean climates
; Soil CO
; Soil organic matters
; Source contributions
; Underground environment
; Vadose Zone
; Soil pollution
; carbon 13
; carbon dioxide
; soil organic matter
; soil water
; abiotic factor
; carbon dioxide
; carbon flux
; carbon isotope
; cavern
; diffusion
; isotopic ratio
; karst
; Mediterranean environment
; seasonal variation
; soil air
; soil analysis
; soil emission
; subterranean environment
; vadose zone
; weather
; advection
; air sampling
; Article
; atmosphere
; cave
; circannual rhythm
; climate
; climate change
; diffusion
; drought
; ecosystem
; effusion
; evaporation
; gas
; humidity
; priority journal
; seasonal variation
; soil
; soil moisture
; weather
; Iberian Peninsula
Scopus学科分类: Environmental Science: Water Science and Technology
; Earth and Planetary Sciences: Earth-Surface Processes
; Environmental Science: Environmental Chemistry
英文摘要: This study characterizes the processes involved in seasonal CO2 exchange between soils and shallow underground systems and explores the contribution of the different biotic and abiotic sources as a function of changing weather conditions. We spatially and temporally investigated five karstic caves across the Iberian Peninsula, which presented different microclimatic, geologic and geomorphologic features. The locations present Mediterranean and Oceanic climates. Spot air sampling of CO2 (g) and δ13CO2 in the caves, soils and outside atmospheric air was periodically conducted. The isotopic ratio of the source contribution enhancing the CO2 concentration was calculated using the Keeling model. We compared the isotopic ratio of the source in the soil (δ13Cs–soil) with that in the soil-underground system (δ13Cs–system). Although the studied field sites have different features, we found common seasonal trends in their values, which suggests a climatic control over the soil air CO2 and the δ13CO2 of the sources of CO2 in the soil (δ13Cs–soil) and the system (δ13Cs–system). The roots respiration and soil organic matter degradation are the main source of CO2 in underground environments, and the inlet of the gas is mainly driven by diffusion and advection. Drier and warmer conditions enhance soil-exterior CO2 interchange, reducing the CO2 concentration and increasing the δ13CO2 of the soil air. Moreover, the isotopic ratio of the source of CO2 in both the soil and the system tends to heavier values throughout the dry and warm season. We conclude that seasonal variations of soil CO2 concentration and its 13C/12C isotopic ratio are mainly regulated by thermo-hygrometric conditions. In cold and wet seasons, the increase of soil moisture reduces soil diffusivity and allows the storage of CO2 in the subsoil. During dry and warm seasons, the evaporation of soil water favours diffusive and advective transport of soil-derived CO2 to the atmosphere. The soil CO2 diffusion is enough important during this season to modify the isotopic ratio of soil produced CO2 (3–6‰ heavier). Drought induces release of CO2 with an isotopic ratio heavier than produced by organic sources. Consequently, climatic conditions drive abiotic processes that turn regulate a seasonal storage of soil-produced CO2 within soil and underground systems. The results here obtained imply that abiotic emissions of soil-produced CO2 must be an inherent consequence of droughts, which intensification has been forecasted at global scale in the next 100 years. © 2017 Elsevier Ltd Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/82820
Appears in Collections: 气候变化事实与影响
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作者单位: Department of Geology, National Museum of Natural Sciences (MNCN-CSIC), Madrid, Spain; Geomnia Natural Resources SLNE, Madrid, Spain; Department of Biology and Geology, University of Almeria, Almeria, Spain; Department of Civil Engineering, University of Alicante, San Vicente del Raspeig, Alicante, Spain; Department of Environment and Earth Sciences, University of Alicante, San Vicente del Raspeig, Alicante, Spain
Recommended Citation:
Garcia-Anton E,, Cuezva S,, Fernandez-Cortes A,et al. Abiotic and seasonal control of soil-produced CO2 efflux in karstic ecosystems located in Oceanic and Mediterranean climates[J]. Atmospheric Environment,2017-01-01,164