Ocean acidification, resulting from rising atmospheric carbon dioxide concentrations, is a pervasive stressor that can affect many marine organisms and their symbionts. Studies which examine the host physiology and microbial communities have shown a variety of responses to the ocean acidification process. Recently, several studies were conducted based on field experiments, which take place in natural CO2 vents, exposing the host to natural environmental conditions of varying pH. This study examines the sea anemone Anemonia viridis which is found naturally along the pH gradient in Ischia, Italy, with an aim to characterize whether exposure to pH impacts the holobiont. The physiological parameters of A. viridis (Symbiodinium density, protein, and chlorophyll a+c concentration) and its microbial community were monitored. Although reduction in pH was seen to have had an impact on composition and diversity of associated microbial communities, no significant changes were observed in A. viridis physiology, and no microbial stress indicators (i. e., pathogens, antibacterial activity, etc.) were detected. In light of these results, it appears that elevated CO2 does not have a negative influence on A. viridis that live naturally in the site. This suggests that natural long-term exposure and dynamic diverse microbial communities may contribute to the acclimation process of the host in a changing pH environment.
Bibliographical noteFunding Information:
The work was partially supported by the US-Israel Binational Science Foundation grant no. 2006318 to EB and by the Israel Science Foundation 09/328 to MF. This project was also partially funded by a grant (PH-MICROB) from the Association of European Marine Biology Laboratory (ASSEMBLE) to EB and DM. Partial contribution was also provided by the European Project “Mediterranean Sea Acidification under a changing climate” (MedSeA; grant agreement 265103). Thanks are due to all collaborators from Stazione Zoologica “A. Dohrn” for their help during the fieldwork.
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics
- Soil Science