Roots and fungi accelerate carbon and nitrogen cycling in forests exposed to elevated CO2.
Ecol Lett
; 15(9): 1042-9, 2012 Sep.
Article
em En
| MEDLINE
| ID: mdl-22776588
ABSTRACT
A common finding in multiple CO(2) enrichment experiments in forests is the lack of soil carbon (C) accumulation owing to microbial priming of 'old' soil organic matter (SOM). However, soil C losses may also result from the accelerated turnover of 'young' microbial tissues that are rich in nitrogen (N) relative to bulk SOM. We measured root-induced changes in soil C dynamics in a pine forest exposed to elevated CO(2) and N enrichment by combining stable isotope analyses, molecular characterisations of SOM and microbial assays. We find strong evidence that the accelerated turnover of root-derived C under elevated CO(2) is sufficient in magnitude to offset increased belowground inputs. In addition, the C losses were associated with accelerated N cycling, suggesting that trees exposed to elevated CO(2) not only enhance N availability by stimulating microbial decomposition of SOM via priming but also increase the rate at which N cycles through microbial pools.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Microbiologia do Solo
/
Árvores
/
Dióxido de Carbono
/
Ciclo do Carbono
/
Nitrogênio
Idioma:
En
Revista:
Ecol Lett
Ano de publicação:
2012
Tipo de documento:
Article
País de afiliação:
Estados Unidos