Publication Date:
2024-03-15
Description:
Atmospheric CO2 partial pressure (pCO2) is expected to increase to 700 µatm or more by the end of the present century. Anthropogenic CO2 is absorbed by the oceans, leading to decreases in pH and the CaCO3 saturation state of the seawater. Elevated pCO2 was shown to drastically decrease calcification rates in tropical zooxanthellate corals. Here we show, using the Mediterranean zooxanthellate coral Cladocora caespitosa, that an increase in pCO2, in the range predicted for 2100, does not reduce its calcification rate. Therefore, the conventional belief that calcification rates will be affected by ocean acidification may not be widespread in temperate corals. Seasonal change in temperature is the predominant factor controlling photosynthesis, respiration, calcification and symbiont density. An increase in pCO2, alone or in combination with elevated temperature, had no significant effect on photosynthesis, photosynthetic efficiency and calcification. The lack of sensitivity C. caespitosa to elevated pCO2 might be due to its slow growth rates, which seem to be more dependent on temperature than on the saturation state of calcium carbonate in the range projected for the end of the century.
Keywords:
Alkalinity, total; Alkalinity anomaly technique (Smith and Key, 1975); Animalia; Aragonite saturation state; BCA assay, Intact protein analyses (Smith et al., 1985); Benthic animals; Benthos; Bicarbonate ion; Buoyant weighing technique according to Davies (1989); Calcification/Dissolution; Calcification rate of calcium carbonate; Calcite saturation state; Calculated; Calculated after Jeffrey & Humphrey (1975); Calculated using seacarb after Nisumaa et al. (2010); Carbon, inorganic, dissolved; Carbonate ion; Carbonate system computation flag; Carbon dioxide; Chlorophyll a+c2; Cladocora caespitosa; Cnidaria; Coast and continental shelf; Containers and aquaria (20-1000 L or 〈 1 m**2); DATE/TIME; EPOCA; European Project on Ocean Acidification; Experimental treatment; Gross photosynthesis; Identification; Laboratory experiment; Measured; Mediterranean Sea; Metrohm 665 Dosimat titrator; Microscopy; Net photosynthesis rate; OA-ICC; Ocean Acidification International Coordination Centre; Other studied parameter or process; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); pH; pH meter (Metrohm, 826 pH mobile); Photosynthetic efficiencies; Primary production/Photosynthesis; Proteins; Pulse Amplitude Modulated fluorometer (Diving-PAM, Walz); Respiration; Respiration, oxygen; Salinity; Sample ID; Single species; Strathkelvin oxygen electrode system; Temperate; Temperature; Temperature, water; Zooxanthellae
Type:
Dataset
Format:
text/tab-separated-values, 12601 data points
Permalink
