THE STRUCTURE OF LIFE FORMS OF FLORA OF THE NORTHWEST OF EASTERN EUROPE AS A REFLECTION OF THE IMPACT OF TEMPERATURE ON THE DEVELOPMENT OF FLORA

Abstract

The present papers is a sequel of the series of publications (Biosfera. 2012;4:27-68, 111-205, 397-476) where the ecological structure of flora of the northwest of Eastern Europe (NWEE) is analyzed. Temperature is a factor of the evolutionary development of flora, mainly its life forms (LF). Therefore, the features of LF spectrum of NWEU flora are considered as they have been molded under the pressure of changes in temperature, which were many times redirected and otherwise modified over the last twenty thousand years in NWEE. The structure of LF spectrum of the whole NWEE flora and of its definite complexes have specific features formed by not only the present temperature conditions but also by the relatively recent (within 20 000 years before present) history of formation of the terrestrial ecosystems of NWEE. Despite the overt predominance of the boreal and temperate sylvan complexes in NWEE, the structure of species spectrum of NWEE flora is markedly depleted in phanerophytes in comparison with the biomes “forests of moderately cool zones” and, especially, “forests of moderately warm zones”. This feature is caused by the relative juvenility of NWEE ecosystems and their migratory origin, as well as by the deficit of heat supply. The structures of LF spectra of defined floristic complexes more or less correspond to LF spectra of respective biomes where the sets of their constituent species have their specific temperature optimums.