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Chapter 1 introduces tertiary amide-based reductive functionalisation strategies as attractive access points towards medicinally relevant α-branched tertiary amine building blocks. Within the scope of this synthetic transformation, Vaska’s complex is highlighted as a chemoselective transition metal catalyst that has come to the forefront for facilitating tertiary amide and lactam hydrosilylation in a mild and efficient manner in both small molecular systems and complex natural product synthesis. Chapter 2 provides a brief description of the Density Functional Theory-based computational methods that were used in Chapters 3 and 5 to complement the corresponding experimental findings. Chapter 3 describes the development of a dual catalytic umpolung reductive functionalisation strategy that enabled the generation of nucleophilic α-amino radical intermediates from robust tertiary amide starting points under a mild set of hydrosilylative/photocatalytic conditions. The work showcases how a tandem, dual catalytic approach can be utilised to enable reductive coupling of amides with electrophiles, previously inaccessible using Vaska’s complex-based hydrosilylative chemistry. Chapter 4 demonstrates how a derivative of Vaska’s complex can facilitate the hydrosilylation of α,β-unsaturated ketones. This finding provided a new synthetic opportunity for the iridium (I)-catalysed reductive functionalisation strategy to be used with carbonyl functionalities beyond the established tertiary amide motif. Inspired by the dual catalytic methodology developed in Chapter 3, the hydrosilylation step was combined with a secondary, chiral catalytic cycle to access enantioenriched products from feedstock enones, which have been thus far unprecedented for Vaska’s catalyst-based methodologies. Chapter 5 features a computational study that was undertaken to elucidate the mechanism and origins of stereoselectivity for a novel, organocatalytic, nucleophilic desymmetrisation of prochiral phosphonate ester reaction developed in the Dixon group. The systematic approach that was used to construct a computational model of the experimental conditions is presented. An analysis of the key, non-covalent interactions that governed both stereoselectivity and reactivity of the system is also provided.

Fragmentation and actual forest pattern assessment is necessary for resource management and for biodiversity conservation. Highly informative are the results of research on the vegetation dynamics by comparing geobotanical maps compiled at different times. As a result of investigation discuss fragmentation indexes and forest pattern metric characteristics evaluated by using actual electronic geobotanical map of Tatarstan (scale 1:200 000), M. V. Markov’s (1944) geobotanical map and geostatistic methods. When comparing the quantitative integral indicators of the forest pattern, a sharp increase in the number of patchs is observed due to the forest fragmentation; a decrease in the average area of the patchs of natural formations (spruce, oak and pine forests); an increase in the areas of aspen and birch forests. For assessing the state of vegetation cover, the index of variability and the index of disturbance of forest vegetation were used, calculated as the ratio of the area of conditionally indigenous and long-derived forest patchs to the area of short-derived forests and to the cultivated plantations area, respectively. Calculations of the fractal dimension and other coefficients characterizing the shape of the pattern revealed that these indicators indirectly reflect the intensity and duration of the anthropogenic load on the territory.

© 2017 Gebrüder Borntraeger, 70176 Stuttgart, Germany. The Republic of Tatarstan is situated between forest and steppe natural zones in the boreal mega-ecotone and has a high species and plant community diversity. The Vegetation Database of Tatarstan (GIVD Database ID: EU-RU-011) is based on phytosociological relevés, herbaria and floristic records. It includes over 8,000 plot records, almost half of them being georeferenced. The database is part of the European Vegetation Archive (EVA) and sPlot projects. In EVA it has a semi-restricted access mode.

© 2014 AENSI Publisher All rights reserved. Forest vegetation of modern landscapes is a complex of successional systems, including communities at different stages of degressively demutational dynamics. Changes affect composition of species, forming forest stand and ground cover. The primary production and stocks of forest ecosystem biomass vary depending on the environmental conditions of the habitat and successional stages. During the research, we have identified three types of succession systems formed under conditions of territorial complexes studied: a succession system of lime-oak nemoral forests in the NTC (natural territorial complex) of high interfluvial plains, succession system of spruceoak- linden nemoral forests in the NTC of high interfluvial plains and succession system of Raifa spruce moos forests in the NTC of indigenous valley slopes. Birch and limetree forests are the most productive.

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. © Pleiades Publishing, Ltd., 2009.

A method of visualization of multispectral remote sensing data hierarchical structure for their analysis by an expert is described. The method is based on visualization of the segmented image that corresponds to the selected by the expert part of hierarchic clusterization dendrogram of remote sensing multispectral image. The above dendrogram is a hierarchy of the spectral patterns of the studied objects. The choice of the dendrogram part results from the aimed visual search by the expert of the studied objects on the segmented images by use of his visual abilities as well as knowledge and intuition. The factors producing errors are investigated, and ways of their reduction are described.