Coral calcification in a changing World and the interactive dynamics of pH and DIC upregulation.
Nat Commun
; 8: 15686, 2017 05 30.
Article
em En
| MEDLINE
| ID: mdl-28555644
ABSTRACT
Coral calcification is dependent on the mutualistic partnership between endosymbiotic zooxanthellae and the coral host. Here, using newly developed geochemical proxies (δ11B and B/Ca), we show that Porites corals from natural reef environments exhibit a close (r2 â¼0.9) antithetic relationship between dissolved inorganic carbon (DIC) and pH of the corals' calcifying fluid (cf). The highest DICcf (â¼ × 3.2 seawater) is found during summer, consistent with thermal/light enhancement of metabolically (zooxanthellae) derived carbon, while the highest pHcf (â¼8.5) occurs in winter during periods of low DICcf (â¼ × 2 seawater). These opposing changes in DICcf and pHcf are shown to maintain oversaturated but stable levels of carbonate saturation (Ωcf â¼ × 5 seawater), the key parameter controlling coral calcification. These findings are in marked contrast to artificial experiments and show that pHcf upregulation occurs largely independent of changes in seawater carbonate chemistry, and hence ocean acidification, but is highly vulnerable to thermally induced stress from global warming.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Água do Mar
/
Oceanos e Mares
/
Calcificação Fisiológica
/
Carbono
/
Antozoários
/
Aquecimento Global
Limite:
Animals
País/Região como assunto:
Oceania
Idioma:
En
Revista:
Nat Commun
Ano de publicação:
2017
Tipo de documento:
Article