Seawater carbonate chemistry and structure of fish assemblages across different coastal habitats

• Main Authors: Coni, Ericka O C, Nagelkerken, Ivan, Ferreira, Camilo M, Connell, Sean D, Booth, David J
• Format: Dataset
• Language: English
• Published: PANGAEA 2021
• Subjects: Abundance; Alkalinity; total; standard deviation; Aragonite saturation state; Area; Benthos; Bicarbonate ion; Biomass; wet mass per area; Biomass/Abundance/Elemental composition; Body size; Calcite saturation state; Calculated using seacarb after Nisumaa et al. (2010); Carbon; inorganic; dissolved; Carbonate ion; Carbonate system computation flag; Carbon dioxide; CO2 vent; Coast and continental shelf; Community composition and diversity; Community density; Entire community; Field observation; Figure; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Growth/Morphology; Habitat; Individuals; 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; Rocky-shore community; Salinity; Site; South Pacific; Species; Species richness; Temperate; Ocean acidification
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.934128; https://doi.org/10.1594/PANGAEA.934128

Poleward range extensions by warm-adapted sea urchins are switching temperate marine ecosystems from kelp-dominated to barren-dominated systems that favour the establishment of range-extending tropical fishes. Yet, such tropicalization may be buffered by ocean acidification, which reduces urchin grazing performance and the urchin barrens that tropical range-extending fishes prefer. Using ecosystems experiencing natural warming and acidification, we show that ocean acidification could buffer warming-facilitated tropicalization by reducing urchin populations (by 87%) and inhibiting the formation of barrens. This buffering effect of CO2 enrichment was observed at natural CO2 vents that are associated with a shift from a barren-dominated to a turf-dominated state, which we found is less favourable to tropical fishes. Together, these observations suggest that ocean acidification may buffer the tropicalization effect of ocean warming against urchin barren formation via multiple processes (fewer urchins and barrens) and consequently slow the increasing rate of tropicalization of temperate fish communities.