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A comprehensive study was performed of the deformation and temperature behavior during quasi-static tension, as well as the peculiarities of accumulation and dissipation of energy during plastic deformation. Microstructural analysis at the pre-fracture stage of pure titanium and Ti-45Nb alloy in the coarse grain (CG) and ultrafine-grained (UFG) states was also conducted. It was shown that substructural and dispersion hardening leads to a change in the regularities of dissipation and accumulation energies during deformation of the samples of the pure titanium and Ti-45Nb alloy in the UFG state. Some features of structural transformations during deformation of the pure titanium and Ti-45Nb alloy samples in the CG and UFG states were studied. A band and cellular-network and fragmented dislocation structure was formed in the case of the CG state, while large anisotropic fragments were formed in the UFG state, thus specifying a local softening of the material before fracture.

Summary. We investigated breeding densities and distribution of the woodpigeon Columba palumbus in woodland and urban habitats of Lithuania, Belarus and the Kaliningrad oblast (administrative district) of Russia. In Lithuania and Belarus, where the urbanisation process of the woodpigeon is in an initial phase, breeding densities in woodland habitats are higher than in urban areas. In the Kaliningrad oblast of Russia, where abundant urban populations have been established in towns for decades, breeding densities in urban habitats are significantly higher than in woodland sites. Available data indicate that at present the eastern border of the European distribution of well-established urban woodpigeon populations extends approximately along the western border of Lithuania, Belarus and Ukraine.

The paper presents data of the 1999–2005 monitoring of the Aquatic Warbler (Acrocephalus paludicola) density, its timing of breeding and breeding success at the Zvanets mire, which hosts about 35% of the European and 64% of the Belarusian population of the species. The density of the species at the mire is characterised by significant yearly fluctuations and is closely linked to the water level in the mire. Nesting conditions for the Aquatic Warbler at the mire were extremely unstable and changed not only in different years, but also within a breeding season. Females can vary the timing of breeding and nest placement quite freely depending on nesting conditions. The main factor influencing breeding success is predation. Breeding success and habitat productivity (the number of fledglings, which have successfully left the unit of habitat) decrease in years when environmental conditions are unusual. In such years birds build their nests in an extraordinary way, making them more accessible to predators. Thus,...

Understanding the links between breeding and wintering areas of migratory species has important ecological and conservation implications. Recently, stable isotope technology has been used to further our understanding. Stable isotope ratios vary geographically with a range of biogeochemical factors and isotope profiles in organisms reflect those in their food and environment. For inert tissues like feathers, isotope profiles reflect the environment in which they were formed. Following large-scale habitat destruction, the globally threatened aquatic warbler Acrocephalus paludicola has a fragmented breeding population across central Europe, largely in Belarus, Poland and Ukraine. The species' sub-Saharan African wintering grounds have not yet been discovered, and this significantly hampers conservation efforts. Aquatic warblers grow their flight feathers on their wintering grounds, and we analysed stable isotope ratios (delta(15)N, delta(13)C, delta D) in rectrices of adults from six main breeding sites (subpopulations) across Europe to determine whether different breeding subpopulations formed a single mixed population on the wintering grounds. delta(15)N varies considerably with dietary trophic level and environmental factors, and delta D with the delta D in rainfall; neither varied between aquatic warbler subpopulations. Uniform feather delta(15)N signatures suggest no major variation in dietary trophic level during feather formation. High variance and inter-annual differences in mean delta D values hinder interpretation of these data. Significant differences in mean delta(13)C ratios existed between subpopulations. We discuss possible interpretations of this result, and consider differences in moulting latitude of different subpopulations to be the most parsimonious. delta(13)C in plants and animals decreases with latitude, along a steep gradient in sub-Saharan Africa. Birds from the most northwesterly breeding subpopulation (Karsibor, Poland) had significantly lower variance in delta(13)C and delta(15)N than birds from all other sites, suggesting either that birds from Karsibor are less geographically dispersed during moult, or moult in an area with less isotopic heterogeneity. Mean delta(13)C signatures from winter-grown feathers of different subpopulations were positively correlated with the latitude and longitude of breeding sites, suggesting a strong relationship between European breeding and African winter moulting latitudes. The use of stable isotopes provides novel insights into migratory connectivity and migration patterns in this little-known threatened species.

At present highly significant for long-term observations are not only traditionally protected territories, which have been investigated for decades, but also the transboundary ones, especially those enjoying international status of protection (such as Ramsar territories). That is why the following four territories – the Berezinski Reserve, the Cepkeliai/Kotra wetland complex, Lake Drūksiai/Drisviaty with adjacent wetlands, the Olmany Wood and Mire Complex – are proposed by Belarus as LTER sites.

The Raman spectra of trihalides of the Fifth Group, BiCl3, AsCl3, AsBr3, SbBr3 and PCl3, in the gas, liquid and solid were obtained. A normal coordinate analysis was performed. The intermolecular force constants were calculated from variations of the intramolecular force constants of the molecule during the phase transition. The half-periods of librations in the liquid and lattice frequencies in the crystal were calculated and the lattice spectrum of the crystal was interpreted. It is shown that for a heavy central atom the calculation of intermolecular force constants may be performed in the approximation of a diagonal potential energy matrix. For a light central atom such an approximation may be used only for estimates. In this case the use of a complete potential energy matrix of a molecule is necessary for an accurate calculation.