Application of a two-pool model to soil carbon dynamics under elevated CO2.
Glob Chang Biol
; 21(12): 4293-7, 2015 Dec.
Article
in En
| MEDLINE
| ID: mdl-26313640
ABSTRACT
Elevated atmospheric CO2 concentrations increase plant productivity and affect soil microbial communities, with possible consequences for the turnover rate of soil carbon (C) pools and feedbacks to the atmosphere. In a previous analysis (Van Groenigen et al., 2014), we used experimental data to inform a one-pool model and showed that elevated CO2 increases the decomposition rate of soil organic C, negating the storage potential of soil. However, a two-pool soil model can potentially explain patterns of soil C dynamics without invoking effects of CO2 on decomposition rates. To address this issue, we refit our data to a two-pool soil C model. We found that CO2 enrichment increases decomposition rates of both fast and slow C pools. In addition, elevated CO2 decreased the carbon use efficiency of soil microbes (CUE), thereby further reducing soil C storage. These findings are consistent with numerous empirical studies and corroborate the results from our previous analysis. To facilitate understanding of C dynamics, we suggest that empirical and theoretical studies incorporate multiple soil C pools with potentially variable decomposition rates.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Atmosphere
/
Soil
/
Carbon Dioxide
/
Carbon Cycle
/
Models, Theoretical
Type of study:
Prognostic_studies
Language:
En
Journal:
Glob Chang Biol
Year:
2015
Document type:
Article
Affiliation country:
United States