Losses and recovery of organic carbon from a seagrass ecosystem following disturbance.
Proc Biol Sci
; 282(1817): 20151537, 2015 Oct 22.
Article
em En
| MEDLINE
| ID: mdl-26490788
ABSTRACT
Seagrasses are among the Earth's most efficient and long-term carbon sinks, but coastal development threatens this capacity. We report new evidence that disturbance to seagrass ecosystems causes release of ancient carbon. In a seagrass ecosystem that had been disturbed 50 years ago, we found that soil carbon stocks declined by 72%, which, according to radiocarbon dating, had taken hundreds to thousands of years to accumulate. Disturbed soils harboured different benthic bacterial communities (according to 16S rRNA sequence analysis), with higher proportions of aerobic heterotrophs compared with undisturbed. Fingerprinting of the carbon (via stable isotopes) suggested that the contribution of autochthonous carbon (carbon produced through plant primary production) to the soil carbon pool was less in disturbed areas compared with seagrass and recovered areas. Seagrass areas that had recovered from disturbance had slightly lower (35%) carbon levels than undisturbed, but more than twice as much as the disturbed areas, which is encouraging for restoration efforts. Slow rates of seagrass recovery imply the need to transplant seagrass, rather than waiting for recovery via natural processes. This study empirically demonstrates that disturbance to seagrass ecosystems can cause release of ancient carbon, with potentially major global warming consequences.
Palavras-chave
Texto completo:
1
Bases de dados:
MEDLINE
Assunto principal:
Carbono
/
Ecossistema
/
Conservação dos Recursos Naturais
/
Alismatales
País/Região como assunto:
Oceania
Idioma:
En
Revista:
Proc Biol Sci
Assunto da revista:
BIOLOGIA
Ano de publicação:
2015
Tipo de documento:
Article
País de afiliação:
Austrália