Johan Eklöf, researcher at the Department of Ecology, Environment and Plant Sciences, has together with colleagues at the University of Gothenburg recently published an article in the journal Proceedings of the National Academy of Sciences USA (PNAS). The article describes a mesocosm experiment that tested the effects of ocean acidification, warming and presence of herbivores on communities consisting of three types of marine benthic primary producers (eelgrass, filamentous macroalgae and benthic microalgae) and macrofauna. The results show that the presence of efficient herbivores can strongly moderate effects of both ocean acidification and warming on primary producers. Interestingly, results from structural equation modeling (SEM) showed that the indirect climate effects (those mediated by species interactions such as consumption, competition or facilitation) were much stronger than the direct effects. This highlights the need for analytical methods that can tease apart direct and indirect effects when studying impacts of climate change on communities.

Alsterberg C, Eklöf JS, Havenhand J, Sundbäck K, Gamfeldt L. 2013. Consumers mediate the effects of experimental ocean acidification and warming on primary producers. Proceedings of the National Academy of Sciences U.S.A. Vol. 110 issue 21

DOI: http://dx.doi.org/ 10.1073/pnas.1303797110