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| Titel |
Initializing the RothC carbon model: Equilibrium run, physical fractionation, or pedotransferfunctions? |
| VerfasserIn |
Lutz Weihermüller, Alexander Graf |
| Konferenz |
EGU General Assembly 2011
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 13 (2011) |
| Datensatznummer |
250057945
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| Zusammenfassung |
| Knowledge of the soil carbon turnover is essential to predict global climate change
impact on terrestrial carbon stocks. For the prediction of carbon turnover and the
calculation of carbon dioxide efflux from the soil to the atmosphere various models
are available. The widely used RothC model is based on the turnover of different
carbon pools, which have to be initialized for the model run. In general, different
approaches are used for the initialization, depending on the availability on soil
samples or the aim of the study. For the simulation of historical data or large scale
approaches equilibrium runs are often preferred because they are independent of the
availability of soil samples. On the other hand, short term modeling will be often
initialized by physical fractionated carbon pools as suggested by Skjemstad et al.
(2004). Finally, various studies reported pedotransferfunctions (pdfs) or regressions to
estimate carbon pools from easier measureable parameters (commonly total Corg),
whereby these pdfs are restricted to the inert carbon pool (IOM) as reported by
Falloon et al. 1998 or to estimate the ratio between microbial biomass (BIO) and
humified organic matter (HUM) fraction as proposed by Zimmermann et al. (2007).
Unfortunately, there is no pdf or regression reported for the most active carbon pool
RPM. In our study we present a pdf for this RPM ration based on the Corg content
only. Additionally, we used total combustion curves to estimate the RPM ratio from
the temperature dependent CO2 release. In a last step, we compared the different
approaches in terms of CO2 release for a wide range of conditions using the coupled
physically based water, heat, and gas transport model SOILCO2/RothC (Herbst et al.
2008).
References:
Falloon, P.D., P. Smith, et al. 1998. Estimating the size of the inert organic matter pool
from total soil organic carbon content for use in the rothamsted carbon model. Soil Biol
Biochem 30:1207-1211.
Herbst, M, Hellebrand, HJ, et al. (2008). Multiyear heterotrophic soil respiration:
Evaluation 625 of a coupled CO2 transport and carbon turnover model. Ecol Model 214(2-4):
271-283.
Skjemstad, J.O., L.R. Spouncer, et al. 2004. Calibration of the rothamsted organic carbon
turnover model (rothc ver. 26.3), using measurable soil organic carbon pools. Australian
Journal of Soil Research 42:79-88.
Zimmermann, M, Leifeld, J, et al. (2007). Measured soil organic matter fractions can be
related to pools in the RothC model. Eur J Soil Sci 58(3): 658-667. |
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