Red water in the lake »Malo Jezero« (Island of Mljet)

Abstract

      It has been ascertained that the apparition of »red water« at a depth of twenty meters in the »Malo jezero« (The Small Lake) on the island of Mljet during the months of May, June and August 1953, has been provo­ked by two bacterial strains (Rhodopseudomonas sp.).

     In the laboratory experiments it has been shown that these bacterial strains require for their most favourable development enough organic substances, lactic acid and calcium carbonate and that at the time when the »red water« appeared the hydrographic and other conditions of the water in »Malo jezero« did practically fulfil such conditions and thereby enabled the most favourable development of Rhodopseudomonas sp., from the cells' pigment of which the water derives its red-pinkish color.

       It has been determined that the pigment of the bacterial strain Rhodopseudomonas sp. are of a carotenoidis nature.