Shape and size in phytoplankton ecology: do they matter?

This paper summarises the outcomes of the 14th Workshop of the International Association of Phytoplankton Taxonomy and Ecology (IAP). The authorsmostly addressed their contributions on the following topics: morphological and morphofunctional descriptors of phytoplankton, size and shape structure of phytoplankton related to different kinds of environmental variables and the role of morphological and physiological plasticity of phytoplankton in maintaining the (apparently) same populations under different environmental conditions. Case studies from different kinds of aquatic environments (deep and shallow lakes, reservoirs with different age, purpose and trophic state, floodplain wetlands mostly in the temperate region but also from subtropical and tropical ones) have shown that similar environmental forcing calls for similar morpho-functional properties even though the corresponding associations can be markedly different on species level.