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Benthic Foraminifers Fighting Extreme pH and Water Temperatures

Paper Reviewed
Engel, B.E., Hallock, P., Price, R.E. and Pichler, T. 2015. Shell dissolution in larger benthic foraminifers exposed to pH and temperature extremes: Results from an in situ experiment. Journal of Foraminiferal Research 45: 190-203.

Noting that "areas where CO2-enriched gases discharge into shallow marine environments can serve as natural laboratories to study the effects of elevated pCO2 (i.e., ocean acidification) on benthic communities," Engel et al. (2015) go on to describe how they collected live specimens of seven species of large benthic foraminifers from a nearby reef, which they placed in small mesh bags and deployed for five days at six different sites along a temperature gradient (60-29°C) and pH gradient (5.9-8.1).

This protocol revealed, in the words of the four researchers, that "individual specimens of four out of seven larger benthic foraminiferal species retained normal symbiont color and thus appeared to survive exposure to temperature fluctuations of up to 60°C and pH fluctuations from 5.9-7.4." And, therefore, they go on to conclude that "shells of reef-dwelling foraminifers can substantially resist dissolution" under "pH conditions sufficiently extreme to erase any fossil footprint." And that represents good news for this tiny marine organism.

Posted 22 February 2017