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In the report results of the first field experiments on multiple-address bistatic (over-the-horizon, non-line-of-sight (NLOS)) optoelectronic communication systems in the UV wavelength range performed at the IAO SB RAS are considered. Experimental estimates of the error probabilities and their standard deviations are presented.

Eleven resonance functions of the theory of the broadening of molecular lines by foreign atomic gases are calculated for very low temperatures. These functions correspond to the atom-atom potential and to the potential V ( R , ) written as a series in Legendre functions. The functions are presented in the analytical form. The calculations of the broadening coefficients g are performed for the CO lines perturbed by the He and Ar for the temperatures T from 300 to 2 K. It is shown that the dependence g( T ) for low temperatures T is determined by the deep of the potential. For CO-He system the comparison with the experimental data is presented.

The present paper deals with food selectivity of the large herbivores of Eastern Mongolia, governing factors and role in formation of herbivores’ community structure. It was established that due to vegetation degradation a high level of selectivity was characteristic of all herbivores under study, it was conditioned by their morphophysiological features and spatial distribution. Selectivity may provide competitive advantages, but not food niche differentiation. We suppose that the herbivore communities of Eastern Mongolia, both under inspection and in the wild, experience under pasture degradation an increase of the portion of small browsers, which in turn raise the rate of degradation. This interrelationship shows a likely mechanism of formation of intrinsic crises in herbivore communities and may explain extinction processes of big steppe herbivores of the “Mammoth fauna”.

The results of long-term research on forests in natural biogeographical corridors (territories with forests, mires, inland lakes and other land categories) connecting the largest bodies of water in Northern Europe (Baltic Sea-Gulf of Finland and lakes Ladoga and Onego to the White Sea) are reported. These corridors link isolated pieces of the Eurasian taiga biome at the boundary between two of Europe’s physiographic divisions - Fennoscandian Shield and Russian Plain. They facilitate the dispersal and migration of plant and animal species. The straight-line terrestrial stretch between the Gulf of Finland and the White Sea is around 320 km, and it falls into three sections in the southern, middle and northern taiga subzones, respectively. The corridors were characterized and assessed as follows: 1) physiographic (landscape) features; 2) key natural characteristics (typological structure, quantitative ratios, spatial arrangement, productivity, etc.), present-day condition of forests, including data from forest management inventories of the past decade; 3) overall assessment of the forest cover transformation by human impact; 4) current system of protected areas and protective forests, and its capacity to fulfill the functions of the corridors (sufficiency).

On the basis of the accounting of undergrowth in 5 gradations of crown closure density of Scots pine ( Pinus sylvestris L.) stands, growing on the dumps in 4 ecological-geographic areas of Kuzbass, inverse relation of parameters of renewal from hydrothermal coefficient of the district is established. Optimum conditions develop in a steppe kernel where the number of shoots, seed production and undergrowth reaches 110 thousand trees per hectare with crown closure of 50 % and density of forest stand of 0.75 thousand trees of the II class of age on 1 hectare. At decrease or increase of forest canopy density of the main tree stand layer quantitative characteristics decrease. The smallest amount of undergrowth is recorded in the mountain-taiga area - from 0.4 to 23 thousand trees per hectare with a tendency to increase in the process of increasing crown closure. Areas of the northern forest-steppe and the southern forest-steppe on quantitative signs of renewal are intermediate. The number of undergrowth has high direct correlation dependence on the size of the current fructification of forest stands - around a steppe kernel ripens to 3.7 million seeds on 1 hectare, in mountain and taiga - to 0.39 million seeds on 1 hectare. Sowing qualities of seeds - the weight 1000, energy of germination and viability, and morphometric characteristics of 2-year seedlings, which are grown up from them - height, diameter and point of a vital state between ecological-geographic areas have no statistically reliable distinctions, but the characteristics stated above, than in the stands on zone soils. It testifies to usefulness of dumps’ conditions for natural regeneration of Scots pine, high actual reproductive opportunities for pine stands in forest-steppe areas and a steppe kernel, and also potential opportunities of the stands in the mountain and taiga region of the southern Kuzbass.

The fire frequency situation in Zabaykal region from 1964 to 2015 is evaluated and discussed in the paper. The main reasons of decadal increase of fire numbers and the area burned are revealed. The main reasons of high fire frequency and the increase of fire activity in the last decades are shown. The characteristics of the weather conditions in the years of high fire frequency are presented. Fire activity was found to increase not only because of the droughts in the last decades but also due to forest disturbances in Zabaykalsky Krai by illegal logging. Based on the data from 170 sample sites laid out with the use of satellite images, forest inventory data and results of ground sample transects, the impact of the wildfires of different type, form and severity on tree mortality in the light-coniferous forests was estimated, as well as the amount of tree regeneration in the forest areas disturbed by fires, logged sites (both burned and unburned), and sites burned repeatedly was evaluated. Wildfires in the Zabaykal region were found to be strong ecological factor influencing on the probability of existence of many forest ecosystems. In case of further climate warming and repeated fires, the part of the forests may transform to the non forest areas. The steppification of the burned sites in the southern forest-steppe regions and in the low parts of the southern slopes at the border with steppe landscapes as well as desertification in the central parts of the region and swamping of burned sites located in the wet soils are observed. Wind and water soil erosion happens at the large burned sites.

A complex assessment of different elevation dark-forest stands of northern, super wet macro slope of Western Sayan was accomplished. Research was conducted during thirteen years (2001-2013) in low mountains (450 m a.s.l.), middle mountains (700-800 m a.s.l.), and high mountains (1450 m a.s.l.). The biocenoses were defined as damaged. The significant differences in the life status of stands are revealed in different elevations. The life status index is varied from 36.4 (in the middle mountains, temperately warm conditions) till 92.0 (in the low mountains, temperately cold conditions). The Siberian pine ( Pines sibirica Du Tour.) haven’t signs of damage, fir trees are drying according to species specific “under the top” type. The biometric signs (increment and needle parameters) of fir shoots of female and male shoots and vegetative shoots are differed. In whole, there are decreases in the middle mountains and high mountains ecosystems. At the same time needle damage (chlorosis and necrosis, in percent) is increased. The element content of needle is changed. In the stands with the low index in the fir needles accumulated potassium, lead, cadmium, and the zinc content decreased. The changes of element content lead to changes correlations in biophillic and technogenic elements Mn/S, Fe/Mn, F/Ca in high mountains (in 2.2-3.6 times) and in middle mountains strongly damaged (in 1.4-3.7 times) stands. It was suggested, that changes in element composition of Siberian fir needle are shown air pollution in the region.

Percent of latewood of Boguchany and Suzun Scots pine climatypes has been studied in two provenance trials (place of origin and trial place). For Boguchany climatype the place of origin is south taiga of Central Siberia (Krasnoyarsk Krai), the place of trial is forest-steppe zone of Western Siberia (Novosibirsk Oblast) and vice versa for Suzun climatype - forest-steppe zone of Western Siberia is the place of origin, south taiga is the place of trial. Comparison of annual average values of latewood percent of Boguchany climatype in south taiga and forest-steppe revealed the same numbers - 19 %. Annual variability of this trait in south taiga is distinctly lower and equal to 17 %, in forest-steppe - 35 %. Average annual values of latewood percent of Suzun climatype in the place of origin and trial place are close (20 and 21 %). Variability of this trait for Suzun climatype is higher than for Boguchany and equal to 23 % in south taiga and 42 % in forest-steppe. Climatic conditions in southern taiga in Central Siberia in comparison with forest-steppe in Western Siberia make differences between climatypes stronger. Differences between climatypes are expressed in different age of maximal increments of diameter, different tree ring width and latewood percent values and in different latewood reaction to weather conditions.

The results of the study of morphological features variability of the Siberian larch seed scales are presented in the paper. Variation of seed scales size, forms of flat and scale edge ofithave been analyzed. Population analysis has been carried out on the phenotypic races and, depending on growing conditions. Four races of the Siberian larch have been investigated. The populations from highlands and low mountains sites of every race have been studied. Samples of seed scales have been selected from thirty trees on each plot. The length and widthof the seed scale, the form index of scaleand the edge form ofseed scale have been considered. The classification of trees on tight scale, wide scale and intermediate forms have been carried out in accordance with the index form of seed scales. The geographic variation analysis of seed scales sizes showed the differentiation of features between races, and, depending on growing conditions. The trees with small scales dominate in larch populations of Baikal race of this species. The largest seed scales have been found in the trees of Sayan race populations in the Kuznetsky Alatau low mountains sites. Polymorphism in the form of seed scale and form its edge has been detected in the studied larch populations. The dominance of «wide scale» and «intermediate» forms trees have been observed in the northern populations (the polar race). The «intermediate» form trees on type flat seed scale predominate in populations of the Sayan race. The most variability of seed scale forms have been found in populations of the Altai and Sayan races. Increased occurrence of wide scale form in the upper mountain belt have been found in both races (more than 50 %). In contrast, more than 50 % of the trees that have cones of tight scale form have been revealed in populations of the Baikal Olkhon Island at altitude of 500 meters above sea level.

Diagnostics of infectious diseases of trees is based on anatomical and morphological characteristics of the tree damage and determining the participants of this process. In the study of tree diseases caused by fungal pathogens their presence and description of morphological characteristics is necessary. Thus, the studies of the causes of the trees diseases are only possible fora limited amount of time, the determined period of the formation of fruiting bodies of fungi. Keep in mind that not every year the natural conditions are favorable for the basidia formation. The diagnostics of pathogen is complicated in the absence of fruiting bodies. In this case, it is required to carry out additional measures on the cultivation of fruit bodies or obtaining a pure culture of the fungal mycelium to determine the cause of the disease. According to the literature, the genus Armillaria fungi are the most common wood destroyers in all forest areas. In addition, they are found in the botanical gardens, parks, urban areas and on private garden plots. Unlike other fungi that destroy wood trees the mycelium complex Armillaria mellea sensu lato has bioluminescence. This feature allows you to identify them among other basidiomycetes growing in Russia. In this article, based on the experimental results is discussed a method for determining the infestation of trees by root pathogens complex Armillaria mellea s. L. by recording luminescence wood samples. It has been shown that the registration of bioluminescent signal of wood samples can be performed at any time of the year, not just during the growing season. It is supposed the possibility of identifying trees that are infected by mycelium of pathogenic fungi genus Armillaria in the absence of fruiting bodies. It may allow probably early detection of infected trees.