Dynamics of development of juvenile plants in the mountain-tundra belt of the Khibiny Mountains

Abstract

Germination of seeds and survival of seedlings are important characteristics of the functioning of communities. There are few observations in the literature on the dynamics of seed germination in untouched alpine communities. Severe abiotic environmental factors characteristic of high mountains make it difficult for juvenile plants to take root, and they show high mortality in the first year of life. For 9 years (2011-2019), all juvenile plants were recorded on 5 m2 of the mountain-tundra community of the Khibiny Mountains and their further life was traced. For most plants of the alpine tundra community, low germination and high mortality of juvenile plants in the first year of life were confirmed. Seeds of some species of undisturbed plots, did not germinate during the observation period, most of the rest they did not survive. In species of slightly disturbed places, the number of seedlings was proportional to the number of species in the community, with the exception of species that do not have vegetative propagation. In the latter, seed germination was higher. A surge in the number of seedlings was observed in 2016 and 2019. The surviving individuals did not pass into the generative age state for 7-9 years of observations, which confirms the duration of the life cycle of alpine species.