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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.

This paper presents the results of the investigation of the grain structure formation in the intermetallic compound Ni3Al under conditions of its high-temperature synthesis under pressure in a powder mixture of nickel and aluminum of stoichiometric composition and the effect of grain size on the strength properties of the synthesized intermetallic compound. The grain structure was investigated by optical metallography, transmission electron microscopy, and EBSD analysis; the ultimate tensile strength of the intermetallic compound was investigated under the tension of the samples in the temperature range from 20 to 1000 °C. It was found that with a decrease in the grain size, not only does the tensile strength of the intermetallic compound multiply increases but also on the anomalous temperature dependence of the intermetallic compound strength there is a significant shift in the maximum strength value to the region of higher temperatures.

The article presents the results of a study of the influence of a high-temperature synthesis product deformation on the strength properties of a Ni3Al intermetallic compound synthesized under pressure. The anomalous dependence of the strength properties of the synthesized under pressure intermetallic in the temperature range of 20–1000°C is investigated It is established that high-temperature synthesis under pressure forms a gradient low-dimensional grain structure in the volume of the synthesized intermetallic. The results of the appraisal of shear strain role under conditions of axial compression of the synthesis product in the of grains structure formation obtained using numerical simulation are presented. It is established that the pattern of grain size distribution in the volume of the synthesized intermetallic depends on the features of the passage of the shear strain front in the billet at the stage of load influence.

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 tufted duck (Aythya fuligula, Anatidae) is widespread in the Palaearctic across Northern Eurasia. Birds breeding in Northern and Eastern Europe are highly migratory, while populations from Western Europe are partially migratory or resident. The aim of this study is to explore genetic variation within and between ducks breeding in Latvia and migrants sampled in North West Russia and Belarus. The technique of random amplified polymorphic DNA was applied using five random primers (ol-1, ol-9-12). Genetic variability was measured for all tufted ducks investigated and for different sub-populations from various regions. Individual genetic structure and genetic variability was higher in ducks collected from Latvia. Gene diversity of amplified DNA bands in birds of Latvian origin was 24% with 80% polymorphism. Means of gene diversity and polymorphism for tufted ducks sampled in other countries varied from 12 to 14% and from 27 to 40%, respectively. A high number of unique bands characterized ducks breeding in Latvia. The oligonucleotide primers used in this study were suitable to analyze differences among tufted ducks of different origin. Possible explanations for the variation observed among the studied ducks are discussed.

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.

Changes in numbers and distribution of wintering waterfowl species in Belarus observed in recent decades are analysed. Data on species composition and numbers of wintering waterbirds were collected by means of surveys conducted in 1981–1998. The total number of wintering species in Belarus increased from 13 to 35 during 1967–2000 and the number of regularly wintering species did so from one in the 1960s to 13 in the late 1980s. Numbers of wintering waterfowl increased from about 1,000 individuals in 1967 to over 50,000 birds in 1991. Most waterbirds were recorded in southwestern and central Belarus, where winters are milder than in the north of the country. The majority of species and the largest concentrations of wintering birds were recorded on artificial reservoirs polluted by heated waste waters near large industrial centres. It is likely that in Belarus the northernmost ice-free wintering sites were firstly colonised by short-distance late migrants adapted to the environment with low air temperature.

RESUME Grâce a la presence de nombreuses zones humides (2,500 km2 de lacs et etangs, 80,000 km de longueur de rivieres) la Bielorussie (superficie totale 207,600 km2) est l'une des plus importantes aires de reproduction d'un grand nombre d'especes d'oiseaux d'eau nicheurs europeens. Les changements survenus dans les habitats de reproduction de ce pays sont typiques de l'Europe de l'est. Des recensements d'oiseaux d'eau ont ete effectues de 1983 a 1996 selon la methode Kauppinen (1979), dans differents habitats (38 km2 de plaines inondables, 443 km2 d'eaux stagnantes et 740 km de rivieres et de canaux). Les principaux types d'habitats (petits lacs de forets, lacs ayant une productivite basse ou elevee, lacs reservoirs, bassins de piscicultures, plaines marecageuses tres, moyennement ou faiblement inondables, canaux et petites rivieres), ont ete definis en utilisant l'analyse des donnees par groupe (cluster analysis) sur la composition en especes et la densite des oiseaux d'eau par espece, et leur role a et...

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.

The quantity of annually-transferred carbon from biogenic to geological recycling depends on the conditions of the water regime, plants’ mineral nutrition and the duration of the biologically-active temperature period. In Belarus, one hectare of virgin peatland transfers from the atmosphere through biogenic recycling to its geological sink about 150–500 kg of carbon per year, some 550–1,800 kg CO2. One hectare of drained but unused peatland emits 21–23 t (fen mire) or 14–16 t (raised bog) of CO2 annually until the residual peat layer is gone. When mires are drained, they stop performing their natural biospherical functions immediately, resulting in a destabilisation of biospherical processes and cycles. Mire ecosystems remain degraded, with their flora and fauna being destroyed. One of the methods to solve this problem is secondary swamping of drained peatlands in order to restore their natural functionality. A major difficulty of the Yelnia restoration project was to propose a suitable, cheap and reliable dam design that would involve people rather than machines – heavy devices unable to make their way through the mire. Equally important was to calculate the hydrological parameters to avoid flooding the forests surrounding the mire. Having analysed the applicability of different types of water-retaining constructions for the local conditions, it was considered optimal to build pile-fence wooden dams. On canals accessible with heavy machinery, it was proposed to build stone-filled water-retaining constructions.

Data on the density of Aquatic Warbler and plant associations in the marshes of the Sporovskiy reserve (Byelarus') were collected between 1996 and 2003. The species density changed between years from 135 to even 0 males per km². The density and numbers of these birds are governed mainly by changes in the groundwater table caused by floods, droughts or fires. Aquatic Warblers breed successfully when the groundwater table coincides with the topsoil level; the optimal water table lies in the range from 12 cm above the soil to 5 cm below it. Between 1981 and 2002 successful first-clutch breeding occurred 11 times (47.8%); in only 4 years was second-clutch breeding successful (17.3%). First and second clutches both failed in 9 years (39%). The pattern of changes in the population size and data on the recovery of the population size following such unfavourable years indicates that the key factors governing the overall population size are not migration or wintering conditions, but rather the state of the breeding biotopes. Active management of fenland still in its natural state is therefore of paramount importance.