Most of you reading this will be very familiar with the story of how ocean acidification is likely to impact marine calcifying organisms: increased carbon dioxide in the atmosphere is decreasing the pH of the oceans and is proposed to eventually lead to the dissolution of the shells of organisms made from calcium carbonate. It is difficult to work out in the lab, however, exactly what the impact of ocean acidification will be on marine calcifiers, as time pressures favour experiments that only assess short-term acclimation responses of organisms to ocean acidification (rather than long-term potential adaptations). Even when long term experiments have been carried out, they have only looked at the impact of pH change alone (see here), ignoring other relevent variables such as temperature. Continue reading Calcifying plankton and climate change
Whenever I look at the iconic White Cliffs of Dover I am reminded of an interesting fact: much of the south of England is made from plankton. Yes, the chalk (calcium carbonate) found here is predominantly composed of plankton – calcifying single-celled plankton to be precise– that sunk to the sea-floor tens of millions of years ago, was compressed to form chalk, and then uplifted into its present position. The two most abundant calcifying planktonic organisms forming this chalk are the coccolithophores, which form stunning blooms visible from space, and the foraminifera (‘forams’ to their friends). Continue reading Does phosphate thin foram shells?