Tovel the red lake preliminary microbiological studies

The Tovel lake is a small alpine Italian lake located within the Adamello-Brenta natural-park. It was famous for the periodic reddening of its waters due to the blooming of the Glenodinium sanguineum, phenomena that has not occurred since the summer 1964. There is very little information about the microbiological composition of the lake, and we have evaluated, in the years 1998, 1999 and 2000, the microbial counts of aerobic, anaerobic and sulfate-reducing bacteria. We have also evaluated the presence of methanobacteria. Whe have carried out tests in enclosures, where the phosphorus concentration was augmented, evidencing an increase in the microbial population. It seems that an increasing in phosphorus would render the lake more adapt to the growth of microbial populations as well as that of Glenodinium, as indicated by the appearance of the reddening phenomenon.