EFFECT OF ECOLOGICAL AND ALTITUDINAL GRADIENT ON STRUCTURE OF A CENOPOPULATION OF PLEUROSPERMUM-URALENSE IN THE SALAIR CHAIN OF HILLS

Cenopopulations of Pleurospermum uralense Hoffin. (Apiaceae family), a tap-rooted herbaceous monocarp, were studied in different altitudinal subzones of vegetation on the Salair chain of hills (southern part of Western Siberia, Novosibirsk Oblast). In the subzone of chern forests , self-maintenance of the species' cenopopulations is accomplished exc lusively by seed, and the optimum habitat for P. uralense is forest ta ll-grass meadows. In forest phytocenoses of the subzone of pine forest s, regeneration of cenapopulations occurs as a result of mixed or prim arily vegetative propagation of the plants, and the density of cenopop ulations is low.