バイカカ游学人門

摘要

Neiston means organism groups living in the surface water layer. The first data on the neiston of Lake Baikal were obtained by Mazepova in 1957. She found an existence of microorganism community in 0-10 cm stratum under ice. In Baikal the study of neiston has been organized in 1980s. The first result is the fact that popula-tions of some orders of bacterioneiston in the outermost layer (0-5 cm) show remarkably high numbers. It had been considered till she made the work that it was impossible for any organisms to survive in the surface layer of a lake, because of inevitability to die of strong ultraviolet rays. Thus, ultraviolet rays exist it does not necessarily follow that all the living things perish. The study on the groups living in Baikal, which have a tolerance to ultraviolet rays, is continued.