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| Titel |
Assessing Vertical CO2 Production Rates and Surface Fluxes Using Automated Diffusion Chambers |
| VerfasserIn |
F. Albanito, M. B. Jones |
| Konferenz |
EGU General Assembly 2009
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 11 (2009) |
| Datensatznummer |
250022029
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| Zusammenfassung |
| In recent years soil CO2 emissions has been the subject of intense investigation because (i) its
potential role in amplifying global warming; and (ii) gaseous compounds formed in the soil
environment are, in general, good indicator of soil biology and biochemistry. Accurate
techniques used to monitor soil CO2 profile concentrations offers the opportunity to identify
localized carbon dioxide sources and potential sinks in the soil, and to understand the
processes that control CO2 production and emission. In this study, we developed a method to
continuously monitor soil CO2concentration, by using a new type of soil diffusion chamber.
We estimated soil CO2 efflux using a new model to determine the vertical CO2
gradient across the soil profile up to 80 cm depth, in conjunction with models to
determine the soil CO2 diffusion coefficient. Furthermore, we assessed vertical CO2
production rates within the soil profile. Daily mean value of CO2 concentration had a
significant variation correlated to soil temperature. Moreover, the vertical soil CO2
concentration showed similar temporal variation at all depths. From January to
August 2008, seasonal mean values of soil CO2 production varied between 1.97
to 6.84 gC/m2/day across the soil layer 0-10 cm. Between 10 and 20 cm depth
soil CO2 production varied between 0.67 and 2.68 gC/m2/day, and across the soil
layer between 20 to 40 cm depth the CO2 production varied between 0 and 0.02
gC/m2/day. Over the same period, seasonal mean values of modelled soil efflux
ranged between 3.12 and 12.96 gC/m2/day. These values correlated well with soil
temperature and flux values measured using automated soil surface chamber. We
present a simple technique to measure continuously soil CO2 profile by burying small
CO2 diffusion chambers. Overall this experiment points out the ability to measure
continuously, and for prolonged periods of time, CO2 concentration across a soil profile. |
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