Diversity and biogeography
Assessment of regional and global biodiversity and distribution patterns along environmental gradients
We examine basic biodiversity patterns across climatic and functional gradients. Our work includes both the analysis of broad distribution patterns and adaptation in the context of climate as well as smaller-scale distribution patterns in aquatic and terrestrial systems. Specifically, we are currently investigating the effect of precipitation on the interaction between sediment particles - clay, in particular - and living organisms, as well as its effect on the availability of nutrients and xenobiotics. Protists and prokaryotes (bacteria) are particularly amenable to comparative studies between aquatic and terrestrial systems.
Biogeography: Ecophysiological niches in a global context
Organisms are adapted to their environment, as can be seen when comparing similar strains from Antarctica with those from temperate or tropical climates. To that end, strains are more competitive at temperatures most similar to their environment of origin: survival rates of Antarctic strains are better below around 8°C, whereas strains from temperate and tropical climates survive better in slightly higher temperatures.
Plankton diversity as an indicator for water quality and ecosystem services
Microscopic viewing of water samples from nature reveals a wide diversity of life forms. Many of these organisms serve as important indicators of water quality, reacting to climatic change as well as eutrophication, acidification, and heavy metal pollution. Maintaining healthy aquatic ecosystems and the restoration of damaged systems are vital in ensuring the long-term vitality of ecosystem services.