FEST: 'Marine calcification: how do they do it? (And why it matters…)'

Friday Earth Sciences Talk by Dr Lennart de Nooijer (Royal NIOZ)

Many foraminifera form shells made of calcium carbonate. The elemental and isotopic composition of these shells varies greatly from inorganically precipitated calcites, suggesting a strong biological control on the process of CaCO₃ precipitation. Moreover, this composition differs, sometimes greatly, between species, which may indicate that the controls on calcite chemistry is not fixed among all species. For paleoceanographic application, a better grip on this inter-species variability in calcite chemistry is necessary. Here I present the latest insights in environmental controls on element incorporation, biomineralization mechanisms and 500 million years of foraminiferal evolution. The (dis)similarities with other marine calcifying organism will be indicated and an effort will be made to use the current understanding of foraminiferal calcification to predict their response to changes in marine inorganic carbon chemistry (e.g. ocean acidification). This in turn, is necessary to assess the contribution of changes in foraminiferal calcification rates to (surface) marine inorganic carbon cycling.

With the FEST, we intend to bring the departments of Earth Sciences and Physical Geography together. The aim is to present (mostly) Utrecht-based Earth Sciences in an accessible way, primarily in order to stay familiar with each other’s work across disciplines. Simultaneously, this provides an excellent platform to help (in particular MSc.) students in their orientation on possible graduation specialisations and future careers.