Mesocosm CO2 perturbation studies: From organism to community level

Abstract

Mesocosm studies have provided and continue to provide a wealth of information on pelagic ecosystem responses to CO2 induced changes in seawater chemistry (Engel et al., 2004, 2005; Delille et al., 2005; Grossart et al., 2006). The suitability of this technique for conducting interdisciplinary research combining marine ecosystem and biogeochemical approaches with aspects relevant to marine and atmospheric chemistry has been successfully demonstrated. The set of CO2 perturbation experiments conducted until now provides a comprehensive but complex data set which lends itself for detailed meta-analyses to further explore the interplay between the dominant ecosystem drivers and to determine which processes are important to be incorporated in marine ecosystem and biogeochemical models. In spite of some limitations, in situ mesocosm perturbation studies provide an effective tool to unravel the effects of projected future forcing on natural aquatic ecosystems and will provide the link between in vitro experiments and field observations. As human-induced global change continues to alter marine environmental conditions, manipulative experiments at the community to whole ecosystem level will become increasingly relevant.