Can Species Interaction Provide New Insight into Biomineralization Processes?

Abstract:

With ongoing ocean acidification the changes in carbonate ion concentrations and consequent shoaling of the aragonite saturation horizon will be felt earlier in deep-sea ecosystems. Cold-water coral (CWC) colonies and their ecosystem dynamics thus offer a perfect opportunity for learning more about factors controlling deep-sea biomineralization. Our research aims to combine classical views of coral calcification with variability caused by species interaction in order to reveal impacts on skeletal formation in cold-water coral ecosystems. Symbiotic relationships, e.g. with polychaetes, offer great possibilities for studying the different intrinsic and extrinsic influences on biomineralization in CWCs. While the biological aspects of such interactions have been investigated to some extent, the processes of biomineralization which are involved in the aragonite precipitation are still largely unexplored. Our results from multi-proxy studies including high resolution mapping of different trace and minor element compositions highlight variations in growth rates, metabolic activity and precipitation patterns during calcification. The results will be discussed in light of nutrient availability, possible seasonality, and potential for pH reconstruction.