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The Impact of Ocean Acidification and Warming on an Intertidal Rock Pool Community

Paper Reviewed
Legrand, E., Riera, P., Bohner, O., Coudret, J., Schlicklin, F., Derrien, M. and Martin, S. 2018. Impact of ocean acidification and warming on the productivity of a rock pool community. Marine Environmental Research 136: 78-88.

Intertidal rock pools are typically composed of a diverse assemblage of seaweeds and invertebrates that form highly productive habitats with strong interactions among species (e.g., herbivory and competition). Such communities regularly experience large fluctuations in daily and seasonal physical-chemical parameters, including temperature and pH, yet little is known with respect to how such environments (and the species inhabiting them) might respond to any future ocean acidification and global warming.

Seeking to provide some information in this regard, Legrand et al. (2018) set out to investigate "the combined effect of ocean acidification and warming on the productivity of rock pool multi-specific assemblages composed by two corralling algal species (Ellisolandia elongate and Lithophyllum incrustans), three fleshy algal species (Chondrus crispus, Ulva sp. and Bifurcaria bifurcata) and two grazer species (Patella ulyssiponensis and Steromphala pennanti)." These species were collected from mid-intertidal rock pools off the shore of Roscoff, Brittany, France and brought back to the laboratory where they were utilized in one of two three-month experiments to mimic seawater temperature and pCO2 conditions under current and predicted (+3 °C above and -0.33 pH below ambient) winter and summer seasons.

In describing their several findings, Legrand et al. state that (1) the intertidal organisms they studied "exhibited species-specific responses to increased temperature and pCO2," (2) "increased temperature and pCO2 have no effect on assemblage photosynthesis, which was mostly influenced by fleshy algal primary production" and (3) "the response of coralline algae to ocean acidification and warming depended on the season, which evidenced the importance of physiological adaptations to their environment in their response to climate change."

Consequently, the seven researchers conclude that "the present results evidenced that rock pool assemblages appear relatively robust to changes in temperature and pCO2, in terms of primary production."

Posted 17 August 2018