Per Juel Hansen


Marine Biological Section
Strandpromenaden 5
DK-3000 Helsingør

Phone: +45 353-21985
Cell phone: +45 26782117

Physiology and ecology of marine planktonic protists

I am generally interested in physiology and ecology of planktonic organisms, community structure and function of microbial communities in marine environments. Recently, I have worked on effects of low and elevated pH on planktonic organisms and macro algae, inorganic carbon limitation of marine phytoplankton and macroalgae, and on mixotrophy and symbiosis among protists. The focus of my research group is presently is on 1) Toxic algae associated with fish kills. We work with natural product chemists to discover new algal toxins associated with fish kills, and with fish physiologists on the mechanisms behind fish kills and possible immunological reactions of fish towards algal toxins. Finally, we study the costs and benefits of toxin production of marine phytoplankton, 2) Mixotrophy and acquired phototrophy among marine protists. We study to the importance of bacterivory among small phytoflagellates and gene expression, photophysiology and nutrient uptake in marine protists with acquired phototrophy.

Current main projects

  • Secondary metabolites from aquatic microorganisms and their impact on seafood and Freshwater fish aquaculture (SAFEFISH; Innovation Fund Denmark, 2015-2019)
  • Acquired phototrophy among marine Protists (AQ-mix; The Danish Council for Independent Research, 2015-2019)
  • Bringing the paradigm for marine pelagic production into the 21st century: incorporating mixotrophy into mainstream marine research (MixITiN; EU-ITN Project, 2017-2021)
  • MarineBasisDisko. A marine monitoring programme in Disko Bay, Greenland. Part of the Greenland Environmental Monitoring programme (GEM) (MarineBasisDisko, Ministry of the Environment, since 2018)