Publication Date:
2024-03-15
Description:
Coastal ecosystems that are characterized by kelp forests encounter daily pH fluctuations, driven by photosynthesis and respiration, which are larger than pH changes owing to ocean acidification (OA) projected for surface ocean waters by 2100. We investigated whether mimicry of biologically mediated diurnal shifts in pH-based for the first time on pH time-series measurements within a kelp forest-would offset or amplify the negative effects of OA on calcifiers. In a 40-day laboratory experiment, the calcifying coralline macroalga, Arthrocardia corymbosa, was exposed to two mean pH treatments (8.05 or 7.65). For each mean, two experimental pH manipulations were applied. In one treatment, pH was held constant. In the second treatment, pH was manipulated around the mean (as a step-function), 0.4 pH units higher during daylight and 0.4 units lower during darkness to approximate diurnal fluctuations in a kelp forest. In all cases, growth rates were lower at a reduced mean pH, and fluctuations in pH acted additively to further reduce growth. Photosynthesis, recruitment and elemental composition did not change with pH, but ?(13)C increased at lower mean pH. Including environmental heterogeneity in experimental design will assist with a more accurate assessment of the responses of calcifiers to OA.
Keywords:
Alkalinity, total; Alkalinity, total, standard error; Aragonite saturation state; Arthrocardia corymbosa; Benthos; Bicarbonate ion; Bicarbonate ion, standard error; Biomass/Abundance/Elemental composition; Bottles or small containers/Aquaria (〈20 L); Calcite saturation state; Calcium; Calcium, standard error; Calculated; Calculated using seacarb after Nisumaa et al. (2010); Carbon, inorganic, dissolved; Carbon, inorganic, dissolved, standard error; Carbon/Nitrogen ratio; Carbon/Nitrogen ratio, standard error; Carbonate ion; Carbonate ion, standard error; Carbonate system computation flag; Carbon dioxide; Chlorophyll a; Chlorophyll a, standard error; Coast and continental shelf; EXP; Experiment; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Gross photosynthesis rate, oxygen; Gross photosynthesis rate, oxygen, standard error; Growth/Morphology; Growth rate; Growth rate, standard error; Incubation duration; Karitane; Laboratory experiment; Macroalgae; Magnesium; Magnesium, standard error; Magnesium carbonate, magnesite; Magnesium carbonate, magnesite, standard error; Maximum photochemical quantum yield of photosystem II; Maximum photochemical quantum yield of photosystem II, standard error; OA-ICC; Ocean Acidification International Coordination Centre; Other; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); Partial pressure of carbon dioxide (water) at sea surface temperature (wet air), standard error; pH; pH, standard error; Phycocyanin; Phycocyanin, standard error; Phycoerythrin; Phycoerythrin, standard error; Plantae; Potentiometric; Potentiometric titration; Primary production/Photosynthesis; Recruitment; Recruitment, standard error; Reproduction; Rhodophyta; Salinity; Single species; South Pacific; Species; Temperate; Temperature, water; Treatment; δ13C, inorganic carbon; δ13C, inorganic carbon, standard error; δ13C, organic carbon; δ13C, organic carbon, standard error; δ15N, organic matter; δ15N, organic matter, standard error
Type:
Dataset
Format:
text/tab-separated-values, 1763 data points
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