Microbiodiversità dei Laghi del Colbricon, Trentino, Italy, un approccio di tassonomia molecolare

We carried out a study of the prokaryotic and eukaryotic communities of the upper Colbricon Lake. The lake is situated at 1922 m a.s.l., in the Natural Park Paneveggio-Pale di S. Martino, in an highly natural area despite the presence of a frequently visited mountain lodge in the summer season. The analysis spanned over seven years and involved a twofold approach: 1) limnological, concerning eukariotic phytoplankton and Cyanophyta; 2) biomolecular, for the study of bacterial communities, achieving their systematic attribution by bioinformatics. We found 125 taxa of eukaryotic phytoplankton and 17 Cyanophyta. The bacterial sampling in fall 2004 revealed 78 prokaryotic taxa. The structure of the bacterial community has been compared with that previously observed, with the same methods prior to the works of waste water drainage pipes re-channelling downstream of the lake. The comparison has allowed to verify the substitution of the previously dominant species with species of different ecological attitude. The former were represented by weakly-pathogenic microorganisms indicative of an anthropic impact, while the new ones are not of clinic kind but reveal an increase of trophic conditions and the presence of hydrocarbon residues, whose origin may be related to the installation near the lodge of a diesel-fuelled auxiliary generator.