title: The effects of thermal and high-CO2 stresses on the metabolism and surrounding microenvironment of the coral Galaxea fascicularis.
abstract: The effects of elevated temperature and high pCO2 on the metabolism of Galaxea fascicularis were studied with oxygen and pH microsensors. Photosynthesis and respiration rates were evaluated from the oxygen fluxes from and to the coral polyps. High-temperature alone lowered both photosynthetic and respiration rates. High pCO2 alone did not significantly affect either photosynthesis or respiration rates. Under a combination of high-temperature and high-CO2, the photosynthetic rate increased to values close to those of the controls. The same pH in the diffusion boundary layer was observed under light in both (400 and 750 ppm) CO2 treatments, but decreased significantly in the dark as a result of increased CO2. The ATP contents decreased with increasing temperature. The effects of temperature on the metabolism of corals were stronger than the effects of increased CO2. The effects of acidification were minimal without combined temperature stress. However, acidification combined with higher temperature may affect coral metabolism due to the amplification of diel variations in the microenvironment surrounding the coral and the decrease in ATP contents.
authors.affiliation: Department of Chemistry, Biology and Marine Science, University of the Ryukyus, 1 Senbaru, Nishihara-cho, 903-0213 Okinawa, Japan; Shimoda Marine Research Center, Tsukuba University, 5-10-1, Shimoda, 415-0025 Shizuoka, Japan. Electronic address: agostini.sylvain@kurofune.shimoda.tsukuba.ac.jp.
authors.forename: Sylvain
authors.initials: S
authors.lastname: Agostini
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Fujimura
authors.forename: Tomihiko
authors.initials: T
authors.lastname: Higuchi
authors.forename: Ikuko
authors.initials: I
authors.lastname: Yuyama
authors.forename: Beatriz E
authors.initials: BE
authors.lastname: Casareto
authors.forename: Yoshimi
authors.initials: Y
authors.lastname: Suzuki
authors.forename: Yoshikatsu
authors.initials: Y
authors.lastname: Nakano
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D037421:Anthozoa / Q000187:drug effects / Q000378:metabolism / Q000502:physiology* / Q000528:radiation effects; D002113:Calcification, Physiologic / Q000187:drug effects; D002118:Calcium / Q000378:metabolism; D002245:Carbon Dioxide / Q000494:pharmacology*; D002940:Circadian Rhythm; D057894:Coral Reefs; D004777:Environment; D057232:Global Warming; D006358:Hot Temperature / Q000009:adverse effects*; D006863:Hydrogen-Ion Concentration; D008027:Light; D010100:Oxygen / Q000494:pharmacology; D010101:Oxygen Consumption / Q000187:drug effects / Q000502:physiology / Q000528:radiation effects; D010788:Photosynthesis / Q000187:drug effects / Q000502:physiology / Q000528:radiation effects; D012623:Seawater / Q000737:chemistry*; D013312:Stress, Physiological / Q000502:physiology*
chemical_list: D002245:Carbon Dioxide; D000255:Adenosine Triphosphate; D010100:Oxygen; D002118:Calcium
keywords: Acidification; Blanchissement; Bleaching; Corail; Corals; Microenvironment; Microenvirronement; Stress; Stresses