Seawater carbonate chemistry and leaf coloration, photophysiology and photosynthetic pigments of seagrass Zostera noltii

• Main Authors: Repolho, Tiago, Duarte, Bernardo, Dionísio, Gisela, Paula, José Ricardo, Lopes, Ana R, Rosa, Inês C, Grilo, Tiago F, Cacador, Isabel, Calado, Ricardo, Rosa, Rui
• Format: Dataset
• Language: English
• Published: PANGAEA 2017
• Subjects: Alkalinity; total; standard deviation; Antheraxanthin; Aragonite saturation state; Auroxanthin; Benthos; beta-Carotene; Bicarbonate ion; Bottles or small containers/Aquaria (<20 L); Calcite saturation state; Calculated using CO2SYS; Calculated using seacarb after Nisumaa et al. (2010); Caldeira_de_Troia; Carbon; inorganic; dissolved; Carbonate ion; Carbonate system computation flag; Carbon dioxide; Carotenoids; Chlorophyll a; Chlorophyll b; Chlorophyll total; per mass; Coast and continental shelf; De-epoxidation state; Electron transport rate; EXP; Experiment; Experiment duration; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Laboratory experiment; Lutein; Maximum photochemical quantum yield of photosystem II; North Atlantic; OA-ICC; Ocean Acidification International Coordination Centre; Partial pressure of carbon dioxide; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); pH; Ocean acidification
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.875791; https://doi.org/10.1594/PANGAEA.875791

Seagrasses play an essential ecological role within coastal habitats and their worldwide population decline has been linked to different types of anthropogenic forces. We investigated, for the first time, the combined effects of future ocean warming and acidification on fundamental biological processes of Zostera noltii, including shoot density, leaf coloration, photophysiology (electron transport rate, ETR; maximum PSII quantum yield, Fv/Fm) and photosynthetic pigments. Shoot density was severely affected under warming conditions, with a concomitant increase in the frequency of brownish colored leaves (seagrass die-off). Warming was responsible for a significant decrease in ETR and Fv/Fm (particularly under control pH conditions), while promoting the highest ETR variability (among experimental treatments). Warming also elicited a significant increase in pheophytin and carotenoid levels, alongside an increase in carotenoid/chlorophyll ratio and De-Epoxidation State (DES). Acidification significantly affected photosynthetic pigments content (antheraxanthin, beta-carotene, violaxanthin and zeaxanthin), with a significant decrease being recorded under the warming scenario. No significant interaction between ocean acidification and warming was observed. Our findings suggest that future ocean warming will be a foremost determinant stressor influencing Z. noltii survival and physiological performance. Additionally, acidification conditions to occur in the future will be unable to counteract deleterious effects posed by ocean warming.