The Multiple Impacts of "Ocean Acidification" on a Tropical Coral
Takahashi, A. and Kurihara, H. 2013. Ocean acidification does not affect the physiology of the tropical coral Acropora digitifera during a 5-week experiment. Coral Reefs 32: 305-314.
Intrigued by these new and diverse findings, Takahashi and Kurihara set out to measure the rates of calcification, respiration and photosynthesis of the tropical coral Acropora digitifera - along with the coral's zooxanthellae density - under near-natural summertime temperature and sunlight conditions for a period of five weeks. Results of their analysis revealed that these "key physiological parameters" were not affected by either predicted mid-range CO2 concentrations (pCO2 = 744 ppm, pH = 7.97, Ωarag = 2.6) or by high CO2 concentrations (pCO2 = 2,142 ppm, pH = 7.56, Ωarag = 1.1) over the 35-day period of their experiment. In addition, they state that there was "no significant correlation between calcification rate and seawater aragonite saturation (Ωarag)" and "no evidence of CO2 impact on bleaching."
Contrary to what many have long contended, there is mounting evidence that suggests that the negative consequences predicted for the world's marine life in a future high-CO2 world are by no means assured, nor are they likely to be widespread.
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