Italian ring-test on the taxonomy of freshwater benthic diatoms

In 2020, the Alpstream group, in collaboration with CISBA (the Italian Center for the Study of the Environmental Biology) and ISPRA, organized a ring test on the taxonomy of freshwater benthic diatoms, involving 36 laboratories on the whole Italian peninsula. For this intercomparison exercise, all the involved laboratories analysed the same diatom sample, collected in Liguria from a Mediterranean-type watercourse. The results obtained from the participants were compared with those obtained by an international expert, Prof. Bart Van de Vijver from the National Botanic Garden of Meise (Belgium).

The intercalibration exercise highlighted numerous issues, including the lack of harmonization among participants in terms of the nomenclature used and issues related to the identification of particularly challenging species, for which scientific literature is currently scarce.

Due to COVID emergency, a final workshop was organized online.

The final aim of the exercise was to reduce the existing gaps among participants in terms of diatom identification and indices application; we also aimed at establishing common rules in order to obtaine comparable and reliable results from the analysis of the benthic diatom flora in the framework of rive monitoring programs. A final report with the main results obtained during the intercomparison and workshop is available at ISPRA website.