Home – Home – Jornals – Contemporary Problems of Ecology 2005 number 2

The state of aquatic and shoreline macrophyte vegetation of the lake Chany system at the transgressive stage water content is studied. By the materials of 50 complete geobotanical descriptions carried out in 2001-2002 on the basic water bodies of the Chany lake system, the found cenotic diversity of the aquatic and shoreline vegetation has made up 22 syntaxa of association rank of the Braun-Blanquet classification. Two new associations - Bolboschoenetum planiculmis and Charetum altaicae - are described. It is shown that in the series Sargul - Uryum - the mouth region of the rivers Minor Chany - Chinyaikhinsky pool - Yudinsky pool, in parallel with the change of mineralization in the sequence of 0,64-0,75-0,96-0,79-3,11-3,56-5,60-6,37-6,50 g/dm³, the number of syntaxa of association rank changes in a series of 12-7-13-3-4-6-3-3-2. It is demonstrated that both at the regressive and at the transgressive phases of water level, the water bodies of the Chany system (except for the lakes Uryum and Sargul) belong to the reed - fennel-leaved - pondweed type. It has been cleared up that at mineralization values of less than 1 g/dm³ it is not so much the mineralization but the ecotopic diversity that influences the species and cenotic variation of macrophyte vegetation. At mineralization values of more than 1 g/dm³, the mineralization becomes already a limiting factor that limits the spreading of the major part of vascular plants and, as a consequence, the species and cenotic richness of the aquatic and shoreline vegetation decreases.