EN
Papulation ecology is a currently developing direction of studies in plant ecology. The paper presents the state of the art in research on the population of meadow plants. Distinguishing of a individual and evaluation of its age creates many methodical challenges in the case of perennial herbaceous plants. Progress in population studies of many species of perennial plants occurred when criteria allowing determination of the age of a individual and the distinguishing of agestates in its life cycle were adopted. Age structure, dynamics of abundance and developmental phases of the population embracing many species of plants in meadow phytocenoses have been studied. The shaping of phytocenoses, their fluctuations and cyclic variability, as well as exchange of species in the course of succession results from transformation within populations, mutual relations between populations of differentspecies and changes in environmental conditions.