Institute of Biology of Inland Waters, Russian Academy of Sciense, Borok, Nekouzsky raion, Yaroslavskaya oblast 152742, Russia

Abstract

Ca2+ and Mg2+ metabolism was investigated in 7 angiosperms and 3 moss species from fresh water of different mineral content. It is considered that adaptation in the water with low mineral content is connected with the decrease in salt wastes out of an organism. The adaptation of ion-transport system of aquatic plants to living under conditions of low mineralization is higher in mosses than in angiosperms. Characteristics of mosses are very low speed of salt waste in distillate water (Vo) and concentration of balance (Cб). According to suitability of ion metabolism system to the existence in water with low mineralization angiosperms could be divided into three groups. Some species are close to mosses, but the majority of plants are adopted to the water with medium or high mineralization. The difference in ion metabolism is connected with the conditions of origin of the given groups. The authors consider that effective adaptations of were formed in the ancestor group of this taxon.