Algae from Lake Miers, a solar-heated Antarctic lake

Abstract

Lake Miers. a permanently ice-covered. thermally stratified lake in South Victoria Land. Antarctica. was sampled for plant life. 34 taxa are described: 8 blue-green algae. 4 green algae. and 22 diatoms. 6 species are new records for the Antarctic Continent and 11 are new to South Victoria Land. Lake Miers contains fresh water. and its bottom waters are warm (5.25°c) as a result of solar heat storage. Planktonic plants appear to live mainly in a narrow convective region at a depth of 15–18 m. Weak penetration of light to this level suggests that the phytoplankton either is adapted to utilise light of very low intensity for photosynthesis. or has a capacity for heterotrophic growth. Most algae collected from the anaerobic lake floor were dead and are thought to be contaminants from shallower parts of the lake and glacial streams. Plants living on the lake bottom must be specialised for anaerobic metabolism.