CO₂ Concentration at the Soil Surface and CO₂ Flux between Soil and Atmosphere in Temperate-Arid Regions in Northern Hemisphere

Abstract:

Carbon dioxide plays important role in various spheres of the Earth system (lithosphere, soil, hydrosphere, atmosphere and biosphere) for material of storage, transformation, transfer and interaction. In the research, two approached to measure CO₂ flux at soil surface and in profiles was carried out in situ in arid area. The background CO₂ concentration was 323.49 ± 21.36 × 10-6(volume fraction) in the surface of the atmosphere, and there are seasonal and diurnal change in the carbon dioxide concentration. For CO₂ flux between soil and atmosphere, the average CO₂ flux was 230.05 μmol·m-2·h-1 from the four kind soils, and CO₂ flux exhibited seasonal and diurnal variations too. For CO₂ flux from soil (the chestnut soil, sierozem soil, fragmental soil, and gray-cinnamon soil) that was exposed to air, CO₂ flux increased when soil from 0–60 cm depth was exposed but decreased when soil at 61–70 cm depth was exposed. The results show that 1) vegetation characteristics and temperature greatly affect CO₂concentrationat the soil surface; 2) CO₂ may be released from the soil into the atmosphere at 254.6 t·km^-2·yr^-1 if the soil at 0–70 cm depth is exposed to the air because of a change in land use or land cover; 3) the soil may absorbed CO₂ when plants were not growing in northern hemisphere; 4) The differences in the distribution of heat energy on the Earth's surface indicate a mechanism by which soil can regulate the concentration of CO₂ in the atmosphere of temperate-arid regions in northern hemisphere.

• Periodical: Advanced Materials Research (Volumes 1010-1012)
• Pages: 409-412
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1010-1012.409
• Online since: August 2014
• Authors: Xiang Yang Sun, Xiao Bing Liu, Cheng Da Gao*
• Keywords: Background Concentration of Atmosphere, Flux of CO₂, Global Warming, Greenhouse Gases, Measurement In Situ

References

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DOI: 10.1007/s10661-010-1505-5

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