Posts Tagged ‘H.S.’

Acidified Seawater: Does It Always Depress Calcification?

Wednesday, June 27th, 2012

Source:  CCR

Findlay, H.S., Wood, H.L., Kendall, M.A., Spicer, J.I., Twitchett, R.J. and Widdicombe, S. 2011. Comparing the impact of high CO2 on calcium carbonate structures in different marine organisms. Marine Biology Research 7: 565-575.

In introducing their study, Findlay et al. (2011) write that “calcifying marine organisms such as molluscs and foraminifera, crustaceans, echinoderms, corals and coccolithophores are predicted to be most vulnerable to decreasing oceanic pH (ocean acidification).” They also, however, say there is a possibility for “increased or maintained calcification under high carbon dioxide conditions,” and they go on to experimentally demonstrate the reality of this phenomenon in different types of calcifying marine animals. More specifically, working with five different calcifying organisms – two gastropods (the limpet Patella vulgata and the periwinkle Littorina littorea), a bivalve mussel (Mytilus edulis), one crustacean (the cirripede Semibalanus balanoides) and one echinoderm (the brittlestar Amphiura filiformis) – Findlay et al. say they “measured either the calcium (Ca2+) concentration in the calcified structures or shell morphological parameters as a proxy for a net change in calcium carbonate in live individuals exposed to lowered pH,” where the lower pH of the seawater employed was created by the bubbling of CO2into header tanks. So what did they find? (more…)