Initial shell-making gains adjusting to more acidic water later erased, 4-year experiment shows
Kai T. Lohbeck/GEOMAR
Armor-plated marine microbes surprised scientists a few years ago by recovering their shell-building prowess in levels of ocean acidification expected under future climate change. But those gains were short-lived, new research shows.
For four years, marine ecologist Lothar Schlüter and colleagues steeped Emiliania huxleyi phytoplankton in seawater acidified by carbon dioxide. After an initial drop in shell calcification — a process that helps sequester CO2 from the atmosphere — the microbes mostly restored their calcification activities within a year, the researchers had reported.
But as the experiment continued, the phytoplankton began making less and less shell material. By the end of the experiment, the phytoplankton in the acidified water were calcifying less than a population that hadn’t been