Coralline algae, a major calcifying component of coastal shallow water communities, have been shown to be one of the more vulnerable taxonomic groups to ocean acidification (OA). Under OA, the interaction between corallines and epiphytes was previously described as both positive and negative. We hypothesized that the photosynthetic activity and the complex structure of non-calcifying epiphytic algae that grow on corallines ameliorate the chemical microenvironmental conditions around them, providing protection from OA. Using mesocosm and microsensor experiments, we showed that the widespread coralline Ellisolandia elongata is less susceptible to the detrimental effects of OA when covered with non-calcifying epiphytic algae, and its diffusive boundary layer is thicker than when not covered by epiphytes. By modifying the microenvironmental carbonate chemistry, epiphytes, facilitated by OA, create micro-scale shield (and refuge) with more basic conditions that may allow the persistence of corallines associated with them during acidified conditions. Such ecological refugia could also assist corallines under near-future anthropogenic OA conditions.
|Journal||Marine Environmental Research|
|State||Published - Oct 2020|
Bibliographical noteFunding Information:
This research was supported by a grant No. 9732 (to G.R. and M.W.) from the Ministry of Science & Technology of the State of Israel and Federal Ministry of Education and Research ( BMBF ), Germany, and by grant from the Israeli Science Foundation (to G.R.). T.G.-H. wish to thank the Mediterranean Sea Research Center of Israel (MERCI) for funding her participation in the course “Microsensor Analysis in the Environmental Sciences”, at the Marine Biological Station Rønbjerg, Denmark. We are grateful to Prof. D. Tchernov and Dr. G. Dishon for the usage of microsensors, N. David for the annual in-situ monitoring of carbonate chemistry at the sampling site, and D. Golomb for assisting with field and lab work . We thank Profs. A. Basso and C. Hurd and Dr. K. Schoenrock for providing their comments and insights on an earlier version of the manuscript. We thank the anonymous reviewers for their suggestions and comments.
© 2020 Elsevier Ltd
- Climate change
- Coralline algae
- Diffusive boundary layer
- Ocean acidification
ASJC Scopus subject areas
- Aquatic Science