02609nas a2200301   4500008004100000020001400041245009400055210006900149260003700218300000900255490000700264520164800271653001001919653002301929653002001952653001901972653001901991653001202010653001902022653002102041653001002062653002202072653001602094653002402110100001902134700002502153856012902178       2009                        eng d  a1354-101300aResponse of Mediterranean coralline algae to ocean acidification and elevated temperature0 aResponse of Mediterranean coralline algae to ocean acidification  aOxfordbBlackwell Publishers Ltd  a20890 v153 aThe effects of elevated partial pressure of CO2 ( p CO2) and temperature, alone and in combination, on survival, calcification and dissolution were investigated in the crustose coralline alga Lithophyllum cabiochae . Algae were maintained in aquaria during 1 year at near-ambient conditions of irradiance, at ambient or elevated temperature (+3 °C) and at ambient [ca. 400 parts per million (ppm)] or elevated p CO2 (ca. 700 ppm). Algal necroses appeared at the end of summer under elevated temperature first at 700 ppm (60% of the thallus surface) and then at 400 ppm (30%). The death of algae was observed only under elevated temperature and was two- to threefold higher under elevated p CO2. During the first month of the experiment, net calcification was significantly reduced under elevated p CO2. At the end of the summer period, net calcification decreased by 50% when both temperature and p CO2 were elevated while no effect was found under elevated temperature and elevated p CO2 alone. In autumn and winter, net calcification in healthy algae increased with increasing temperature, independently of the p CO2 level, while necroses and death in the algal population caused a net dissolution at elevated temperature and p CO2. The dissolution of dead algal thalli was affected by elevated p CO2, being two- to fourfold higher than under ambient p CO2. These results suggest that net dissolution is likely to exceed net calcification in L. cabiochae by the end of this century. This could have major consequences in terms of biodiversity and biogeochemistry in coralligenous communities dominated by these algae. [PUBLICATION ABSTRACT]10aalgae10aAquatic ecosystems10aBiogeochemistry10acarbon dioxide10aClimate change10aGEOLOGY10aGlobal warming10aGreenhouse gases10aOcean10aSurvival analysis10atemperature10aWater acidification1 aSophie, Martin1 aJean-Pierre, Gattuso  uhttps://reefichno.myspecies.info/content/response-mediterranean-coralline-algae-ocean-acidification-and-elevated-temperature