1. Bacterioplankon composition, function and biogeography

• Factors regulating bacterial growth and mortality rates, i.e. protozoan bacterivory and viral lysis

• Geographic distribution of major groups of Betaproteobacteria and Actinobacteria

• Effects of algal derived substrates on shaping bacterioplankton community composition

• Bacteria mediated decomposing processes in natural aquatic ecosystems

• Long-term trends in developing of microbial food webs in reservoirs

2. Phytoplankton primary production, ecology and composition

• Effects of extreme rainfalls on phytoplankton structure and composition along the longitudinal gradient in reservoirs

• Long-term changes in the phytoplankton in response to global climate change

• Competition mechanisms among dominant phytoplankton species

• Polyphasic approach in taxonomic classification of cyanobacteria

3. Lake recovery from acidification

• Constrains and limits of biological recovery from acid stress – a key role of aluminium