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The distribution of tree species in the landscape was studied using the approach based on the comparison of the ecological requirements of species and the properties of ecotopes distinguished by their position in the relief and peculiarities of basement rocks. The types and specificity of ecological regimes were determined for the typical ecotopes of the southern Karelian ridge landscape. The main environmental and successional factors determining the distribution of seven forest-forming tree species in the ecotopes of this landscape were identified. The results of this work can provide a basis for the prognosis of forest vegetation in the landscape studied.  相似文献   
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Fifteen A. baikalensis populations growing in natural and disturbed habitats in the dark-taiga forest belt of the Western Sayan Mountains have been studied with respect to age composition, numbers, and variation and interrelation of vegetative characters and parameters of productivity. Specific features of the effect of gaps in the tree canopy on the state of A. baikalensis cenopopulations have been revealed.  相似文献   
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Some up-to-date methods of analysis of the spatial and age structures of populations, including local population density maps and Ripley’s functions, are described using 20 cenopopulations (CPs) of Adonis vernalis L. as an example. Pregenerative plants have been found to be the most contagious, irrespective of climatic and phytocenotic conditions and land use type. The spatial distribution pattern and structure of A. vernalis are mainly determined by generative plants forming a tussock, irrespective of the climate and vegetation type. This is explained by higher competitiveness of generative plants, which results in a reduced vegetation density at small distances from them (25–50 cm). Within wider areas, plant distribution may be random due to uniformity of local conditions in microhabitats. The formation of distinct plant aggregations is accounted for by insufficient water supply and the intensity and type of anthropogenic impact.  相似文献   
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The stages of ontogeny and morphogenesis of the common chicory were characterized on the basis of long-term observations. A comparative analysis of seed productivity was performed, and the pool of viable seeds in the soil was determined. The ecological–cenotic relationships and the types of population strategy of the species were estimated.  相似文献   
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A discrete approach to the study of ontogeny has made it possible to reveal a high degree of age heterogeneity in P. bifurca cenopopulations. The basal ontogenetic spectrum of cenopopulations has been determined. The index of regeneration is higher in cenopopulations of the young type and decreases in cenopopulations of the old type, whereas the situation with the index of senescence is inverse. The density of cenopopulations depends mainly on parameters of the substrate (density, composition, and moisture), its slope, and the intensity of plant vegetative reproduction and spread.  相似文献   
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