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An assessment is made of the uniqueness of modern vegetation in Prebaikalia as a biogeographical entity. It is shown that its complex structural-cenotic diversity is represented on the new universal geobotanical map of vegetation at a scale of 1:500 000. The map legend, constructed on the principles of V. B. Sochava’s multidimensional and multistage structural-dynamical clas sification of plant communities, displayed more than 160 cenotic subdivisions of vegetation of Prebaikalia representing its differ ent types. An analysis is made of the development paths of vegetation for assessing its evolutionary potential. The study revealed the main stages of philocenogenesis in the Late Cenozoic. Its main directions have been revealed, which are important for un derstanding the characteristics of the region’s modern vegetation cover. The heterogeneity and heterochronicity of modern ceno tic diversity of vegetation is shown. Emphasis is placed on the evolutionary processes of vegetation of Prebaikalia in the Holocene which can last for at least 40 thousand years. In this connection, it is proposed to change interpretation of the Holocene Optimum as an optimum for the evolution of the dark-coniferous taiga of Siberia. It is shown that the genetic linkages of the cenotic struc ture of modern vegetation cover in Prebaikalia are clearly pronounced via regional-typological categories of vegetation reflecting profound links of modern vegetation with natural-geographical regions where its philogenetic processes were taking place in in teraction with the general evolution of the natural environment. An analysis is made of the significance of the floristic and cenotic boundaries having an important biogeographical significance. Such boundaries, on the one hand, are the footprint of the past evolutionary processes in vegetation, and in the natural environment as a whole, and, on the other, indicate the dynamical potential of possible changes in vegetation under global climate change.

To identify current trends in the functioning of the geosystems of the Tunkinskaya depression and the mountains surrounding it, this paper considers the natural course of their development and anthropogenic transformation. The main landscape-forming factor is represented by the characteristics of the morphological structure of the surface of the mountain-basin territories experienc ing the effects of intense current dynamical trends: aeolian processes, debris flow activity and eutrophication which enhance the polychronicity of the landscape structure. Landscape discontinuity is complicated by the ongoing economic activities. Significant areas of the gentle slopes of the depression are occupied by agricultural lands; periodically recurring human-caused fires that are responsible for a widespread occurrence of secondary small-leaved forests. For forecasting the trends in the natural-economic situation, an assessment is made of the rehabilitation dynamics of the biotic component of geosystems. In the absence of the an thropogenic factor, the rehabilitation of natural piedmont pine (Pínus sylvestris) forests will require about 40-50 years, and several centuries in the case of natural mountain taiga larch (Larix sibirica) forests. The characteristics thus identified were used in compiling the landscape map for the Tunkinskaya depression and the mountains surrounding it which gives a complete picture of the current state of the geosystems. Evidence obtained in this study can provide a scientific basis for forecasting the evolution of geosystems, carrying out measures for nature management optimization and in dealing with nature conservation issues.

Presented are the results from investigating glacial terminal basins of Eastern Transbaikalia. The formation conditions are examined for lake basins. This paper provides examples of the parameters of the glacier snout-caused overdeepening crystalline rocks and unconsolidated deposits of intermontane basins. The Late Pleistocene age of the lake basins is determined by the paleogeographical restoration of the ancient glaciations of Transbaikalia. The terminal lakes are direct indicators of the maximum distance of mountain-valley glaciers from the centers of the last glaciation. They Bol’shoe and Maloe Leprindo, Zarod, Nichat ka, Oron, Chitkanda and other lakes. Paleoglaciological restoration of glaciation, and analysis of the neotectonic block structure of the relief determine the genesis of lake depressions occurring in glacial areas. Morphogenetic analysis of terminal formations substantiates the priority of exogenous processes over endogenous processes in the formation of lake basins. The influence of endogenous forces is limited by selective exaration of rocks that are weakened by intense tectonic fissuring. The lake preservation conditions and the dynamics of the filling of glacial lakes with terrigenous material in the Late Pleistocene-Holocene are assessed.

A city is considered as a complex object for study that combines the natural basis and the man-made environment. The landscape-functional differentiation became a fundamental stage of relevant investigations. The modern landscape and functional structures of the territory of Birobidzhan have been studied on the basis of research results and material of previous work. The basic characteristics of the natural and anthropogenic components of Birobidzhan are provided for the period starting from its foundation. Extensive areas of natural landscapes areas little affected by anthropogenic activities have been identified as well as a relatively large number of open spaces and green spaces which refer to potential reserve areas in ecological planning, are identified in the city limits. Furthermore, it was found that the planning structure of Birobidzhan has been an environmentally unreasonable project, which is evidenced by the chaotic location of industrial, residential and recreational areas, and the absence of sanitary protection zones within the urban development. The soil-vegetable cover and planning structure has been used as the main criteria for the selection of landscape-functional complexes. As a result, four landscape-functional complexes were identified in the city: man-made, anthropogenic-man-made, anthropogenic-natural, natural and anthropogenic, with different proportions in the urban system of Birobidzhan. Systematization within these complexes is used as a basis for the legend to the 1:25 000 map “Landscape functional complexes in Birobidzhan”, scale 1:25 000. The results obtained can serve as a basis for a preliminary assessment of the ecological situation and for the development of recommendations for the optimization of the quality of the urban environment. In the structure of the landscape-functional complexes, 35.5 % correspond to the heavily modified technogenic and anthropogenic technogenic landscapes. Some improvements can be achieved by increasing the proportion of anthropogenic-natural complexes and through conservation of those natural and man-made landscape-functional complexes with different levels of disturbance.

We examine the current state of the geosystems on Popov Island. It is found that as a result of the anthropogenic influence there are taking place the transformation of primary forests and an increase in the proportion of adventives vegetation near settlements; depletion of the species composition of lichen cover has been recorded. The soils of the islands are characterized by a small thickness and are highly skeletal of the stony-rubble composition; therefore, most of the island’s territory refers to the erosion-hazardous group of lands. Active sheet erosion is observed on roads and roadsides composed of granites and granitoids, occasional basalts and diorite-basalts dominated by polydominant broad-leaved forests on dark burozems. The anthropogeni cally transformed territories count for 12.57 % of the area. In spite of a relatively strong anthropogenic impact, the geosystems have retained their natural state. The indicator of landscape diversity, and also species diversity of vascular plants and lichens, and the coefficient of natural protection of the territory reflect the persistence of the functioning mechanisms of the system within the island, and ensure its geosystem integrity and the presence of stable internal linkages between natural-territorial com plexes. A reconstruction of the natural environment from data of pollen and radiocarbon analysis revealed natural spatiotempo ral changes of landscapes for the last six thousand years. The structural transformations of geosystems were caused by changes in the climatic regime and occurred in several stages. The latter half of the Atlantic period was characterized by a prevalence of polydominant broad-leaved forests; small-leaved forests dominated during the warming period of the Little Ice Age; the propor tion of broad-leaved species increased during the Little Holocene Optimum and under current global warming.

Pskov oblast and Jewish Autonomous Oblast are used as an example to demonstrate changes in agriculture of the border areas of the Russian Federation. It is shown that between western and eastern regions there are differences in the development of agriculture that are caused not only by agro-climatic conditions but also by the socioeconomic situation. In Pskov oblast, considerable regional funds are invested in the development of large agricultural production, whereas less attention is given to farming than in Jewish Autonomous Oblast with a high proportion of farms that emerged in connection with disintegration of large agricultural enterprises. In Pskov oblast, agricultural enterprises were closed or joined agricultural holdings that work for Moscow or St. Petersburg. A decline in plant-growing implies a reduction in traditional crops (flax and grains). In Jewish Auto nomous Oblast, agricultural organizations dispersed among private enterprises (farms and households), which is explained by the development of small-scale trade. An increase in soybean cultivation is due to its demand in the Russian and international sales markets. The two oblasts show a decrease in livestock population (especially horned cattle) as the cost of keeping is high. In Pskov oblast, most of the livestock are kept in agricultural organizations, whereas in Jewish Autonomous Oblast in private house holds. Cross-border cooperation of Pskov oblast and Jewish Autonomous Oblast also has some features in common. In the two oblasts, foreign investors invest in agriculture. In the former oblast, however, the projects envisage long-term cooperation that includes the development of rural areas located in the zone of influence of the programs; in the latter oblast, investments are for short-term periods with the purpose of obtaining profits from the territory, without any interest shown in its development.

Some issues related to the development of the municipal formations of Irkutsk oblast are considered. It is found that the human population is characterized by the highest sensitivity to impacts of different types, and this factor was used to develop methods of situation analysis of the population response to changes in the socioeconomic environment. The models and methods used are based on notions and equations of reliability theory. The resulting integrated indicator makes it possible to estimate the degree of use of the demographic potential. For the municipal formations of Irkutsk oblast the indicators of integrated life hazard under the existing conditions were calculated on the basis of series of data on the population size for a long period of time. Calculations involve determining the degree of life hazard from the value of demographic response to the impact of multi-level factors of the natural and socioeconomic environment. Results of the calculations identify different trends in the demographic development of cities and districts of Irkutsk oblast discriminating between normal and critical states. A comparative analysis is made of the findings in order to ascertain the characteristics of the transformation of the spatial organization of the territory for the last several decades. General trends for groups of districts and cities, and also some features of differences are revealed. The causes thereof are linked to the inhomogeneity of the region’s socioeconomic conditions. The method of situation analysis presented in this study provides a means of assessing the trends of further development or degradation of settlements. The value of an integrated hazard serves as the indicator of changes in the socioeconomic situation. The suggested technique can be used for historical-demographic comparative analysis and mapping of different regions and stages of their development.

Presented are the results obtained from the radar profiling of the Peretolchin glacier in the Munku-Sardyk mountain range in the south of Siberia (June 2014 and May 2016) using georadar “Oko-2” with the ABDL “Triton” antenna unit operating at the radiation frequency of 50 and 100 MHz. The ice thickness was determined from the profiles and the ice volumes from the cross-sectional areas and distances between profiles. The ice volume was calculated for the body of the Peretolchin glacier to be 0.007 ± 0.0019 km ³ . An analytical method was also used to determine the ice volume according to the type and area of glacier. It is established that the correlation between the volume and the area of the glaciers is expressed by a power function V = kS ^p . The mean ice volume, calculated with due regard for different coefficients, was 0.0061 km ³ . The GlabTop model that takes into account the cross-sectional form of the glacier was used to infer the ice volume: the mean volume for two cross-sections (para bolic and ellipses) was 0.0073 km ³ . It is established that for 110 years since the start of the investigation into the morphology of the Peretolchin glacier, it has increased twice in its length and in area, its volume has decreased by a factor of 3.7, and the lower boundary of the open part of the glacier has risen 184 meters for that time.

This investigation is concerned with the problem of recognition of glacial landforms in arid mountainous areas of Asia us ing satellite imagery. We examine the territory of the Mongun-Taiga mountain range located at the interface of the Russian Altai, Sayan and Mongolian Altai mountains which has been studied for many years by geographers of St. Petersburg State University. The mountain range is home to modern glaciers totaling about 20 km in area, and its climate aridity is favorable for the preservation of a large body of evidence of ancient glaciation. The theoretical basis for this effort was provided by the idea of glaciogenic complexes, i. e. natural complexes, the morphology and structure of which is formed by modern and ancient gla ciations. Using the morphological differences we identified three groups of glaciogenic complexes and assigned their formation time to MIS 4, MIS 2, and to the Late Holocene. Results from comparing data of glacio-geomorphological and paleogeographi cal studies on the territory of the Mongun-Taiga mountain range with corresponding satellite images were used to develop inter pretation standards for different groups of glaciogenic complexes, forming the basis for compiling the map of glaciogenic com plexes of th second and third order for the entire mountain range. Cartometric measurements were used in obtaining the main characteristics of the glaciers of the Mongun-Taiga for ten different time spans. It is found that during the MIS 4 maximum the glaciers advanced to the piedmonts, and their area exceeded the present-day area by more than a factor of 25, with the firn line depression of about 800 m. The largest areas were occupied by glaciers of southward aspects, which is accounted for by a pre dominance of north-westward moisture-carrying glacial streams at that time. The aspect asymmetry of glaciation persisted during the MIS 2 maximum but it had a valley character. It is established that in the Little Ice Age the area of the glaciers exceeded the present-day area by a factor of 2.4, with the firn line depression of 20 m.

This paper discusses the main properties of models and model assessments forming the notion of their quality, which include the accuracy, reliability and details of the description of approximate model assessments. On the basis of taking into account the entire set of quantitative parameters of these characteristics, the notion of the measure of model quality is introduced. The main property determining the model quality is highlighted, namely the accuracy of model calculation using independent data. Ap proximate estimations of the values of a variable in the interval and probabilistic form are considered, which can be constructed on the basis of data on its values in the past. For probabilistic assessments of the values of the variables, it is suggested that, in addition to the measure of accuracy, the measure of informativity should be used, which is determined in terms of entropies of the corresponding probability distribution functions. In developing the algorithms for assessing the measure of quality, special attention is paid to calculating the parameters characterizing the reliability of approximate model assessments and the models themselves. The reliability is assessed in terms of the probabilities of the events occurring when the model is constructed or used. The measure of probability of the model of dependence determined at the stage of constructing it by using the learning sample is calculated as the product of two probabilities: the measure of confidence to the predictors of a dependent variable, and the mea sure of confidence to the operator describing a dependence of this variable on them. Recommendations are made for assessing these probabilities. N view of the stricter requirements for the reliability of predictive assessments, the algorithm is suggested for increasing it by combining into an ensemble the conditional model and unconditional probability assessments.