The advantages and disadvantages of some most common methods of quantitative analysis used in processing of synphytoindication data were analyzed. These methods enabled reflection of important ecological characteristics of plant communities and assessment of the nature of their topological and regional differentiation characterizing α-, β-, γ-diversity. We also examined current debatable issues regarding the use of scales of ecological indicator values and methods of their correct comparison based on bringing to a single "denominator". The visual aspects of the gradient analysis used in assessment of topological differentiation of habitats based on the establishment of various types (vector, combinative and complex) of ecological and coenotic profiles are considered. We focused our attention on the application of optimal models of ordination methods (detrended correspondence analysis – DCA, non-metric multidimensional scaling – NMDS). The use of cluster analysis reflected in various methods of dendrogram constructing was evaluated. The analysis of the above methods allows us to evaluate the efficiency of their use in various aspects of synphytoindication techniques. This allows us to use such data for forecasting and modeling biocoenoses changes and development, for assessment and classification of biotopes, landscape structure (ecomer), zoning (ecochor), as well as for evaluation of the resistance of vegetation to the influence of external factors. The methods and approaches of mathematics and cybernetics are expected to be more widely used in geobotany in the future, since many pressing ecological issues related to non-linear development, emergent changes in the ecosystems properties and search for critical thresholds cannot be solved in a traditional way.

Syntaxonomy of the natural vegetation of the Dniester Canyon, including 20 classes, 30 orders, 44 alliances, and 71 associations, is presented. The natural vegetation of the canyon is formed by communities of the classes Carpino-Fagetea sylvaticae, Quercetea pubescentis, Quercetea robori-petraeae, Alno glutinosae-Populetea albae, Crataego-Prunetea, Festuco-Brometea, Trifolio-Geranietea sanguine, Molinio-Arrhenatheretea, Sedo-Scleranthetea, Phragmito-Magnocaricetea, Bolboschoenetea maritimi, and Isoëto-Nanojuncetea. Grassland vegetation is characterized by the highest syntaxonomic diversity. Quantitative assessment of syntaxonomic diversity in the three-dimensional system of ecological strategies of species according to Ramensky-Grime (CRS) was carried out. Adaptive capabilities, i.e. the potential for possible further development of forest, shrub and grassland habitats, have been assessed. It has been found that the dynamics of forest shrub, grass meadow and steppe communities is determined by successive endoecogenetic processes. In petrophytic communities, fluctuation changes are not manifested and successional changes are rather limited. Significant fluctuations are inherent in floodplain grasslands that depend on the sharp variability of moisture during the growing season. At the same time, it is emphasized that actual realization of these processes depends on influences of external drivers that can be considered as regulatory factors in possible development of syntaxa.

The article provides results of the quantitative score assessment of environmental conditions of plant communities (biotopes) and comparative analysis of the topological (altitude) gradient of changes using the method of synphytoindication and the Mountain Crimean geobotanical zone as an example. Of the 126 biotopes listed for the Mountain Crimea, we selected for the analysis 68 forest, shrub, grassland and petrophytic types, reflecting the patterns of topological differentiation, i.e. β-coenotic diversity within five geobotanical regions and altitudinal zones of the southern and northern macroslopes. In the article, we highlight the specifics of the methodology of field research and data processing, based on geobotanical relevés entered into the database in the TURBOVEG software and selected ecological and coenotic profiles. At the next stage, we assessed the living conditions of the biotopes by applying modern methods and programs TWISPAN, STATISTICA-7. On the basis of key biotopes, we identified combinations within the altitude zones treated as mesocombinations and those within the macroslopes – as macrocombinations. In the article, distribution of biotopes by mesocombinations, macrocombinations and geobotanical regions is provided. The model ecological-coenotic profiles of each geobotanical region of shrub-forest and petrophytic-grass series were built showing distribution of biotopes and graphs of the indicators of major ecological factors. The regularities of altitude changes and the nature of correlation were established. For climatic factors (thermo-, cryoregime, humidity, and climate continentality), we calculated relevant indicators and coefficients used in climatology. The obtained data form the basis for assessing the differentiation of biotopes, comparative analysis of the ecological conditions and forecasting potential changes.

The article provides distribution patterns of natural vegetation depending on topological conditions and outlines the main directions of its anthropogenic transformation. The boundaries as well as botanical and geographical features of the studied district are specified. The syntaxonomic classification of plant communities is presented. The combinative ecological and coenotic profile was created showing distribution patterns of the main plant communities in relation to changes in the indicator values of ecological factors. Three types of mesocombinations are distinguished: forest, grassland (meadow) and swamp-flood ones. Averaged (relevant) indicator values were calculated based on environmental conditions. It has been established that the forest range is characterized by the indicators close to the background ones, which indicate a high stabilizing role of forest ecosystems. Correlative dependence between changes in indicators of certain factors was found, that enables to predict possible cause-and-effect changes. Under current trends of anthropogenic and climatic changes, a decrease in the humidity regime along with raise in soil pH can be expected in the future, while increase in seasonal changes in moisture will accelerate processes of nitrification and soil mineralization. Some habitats within the district are under significant negative effect of invasive species, e.g. the territory between the Lomnytsia River and Kolomyia town is classified as the one under the highest degree of threats due to huge, probably largest in Ukraine, areas of Heracleum sosnowskyi, Erigeron annuus, Solidago canadensis and Rudbeckia laciniata. In the future, this region may undergo substantial transformation and a special attention is required to protect its biodiversity.

A syntaxonomic outline of the floodplain communities of the Dniester Canyon is presented it (comprised by 6 classes, 8 orders, 10 alliances, and 14 associations); their habitat structure is described as well. On the basis of the regular distribution of habitats, topological units of vegetation-ecomers are distinguished; these ecomers are represented by five sigma-syntaxa. The above typology of territorial units within mesocombinations reflects as much as possible the structure, biodiversity and their ecologicalcenotic conditions. It is established that the Dniester floodplain is formed by two types of ecomers: herbaceous (a combination of habitats of water-fringing vegetation) and woodland (habitats of floodplain forests and shrubs). It is found that topological differentiation of ecomers is determined by soil humidity, damping variability, soil aeration and acidity, and anthropogenic activities (cutting, artificial change of hydrological regime).