Lennart De Nooijer
Lennart de Nooijer is a research leader at the Royal Netherlands Institute for Sea Research (NIOZ). He obtained his PhD degree at Utrecht University in 2007 and has since then been working on biomineralization in foraminifera, sponge bioerosion and coral reefs. He has been working at leading marine research institutes like JAMSTEC (Japan) and AWI (Germany) before obtaining a permanent position in The Netherlands. His most notable work is on the experimental characterization of the biological mechanisms that allow organisms to transform seawater into crystalline calcium carbonate. This includes the use of confocal laser scanning microscopy and high-resolution calcite chemical (elemental and isotopic) analysis of foraminiferal calcite.
Biomineralization in foraminifera: how do they do it and how does it affect application of proxies?
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. Here I present the latest insights in the cell-biological controls responsible for calcification, and with a special emphasis on element incorporation. This includes novel approaches to visualize the foraminiferal calcifying fluid, an analysis of the ion exchange that is the basis for Ca- and carbon uptake and modeling to test the effect of physiological and chemical processes on element partitioning.
