Transformation and Reconstitution of Vegetation in the Pre-Baikal

The work represents the results of perennial studies of the structural-dynamic organization of the phytocoenoses, which are subjected during a long period to anthropogenic impact in different, for geographical conditions, areas of western and south-eastern Pre-Baikal. The composition of phytocoenoses, which form at cuttings of forests of different composition and typology is found out. The following parameters are determined: species composition, synfolial differentiation and dominant species of the soil cover reflecting the dynamics of reconstitutional stages of polydominant light-coniferous forests of Pre-Baikalian type. We noticed the peculiarities of transformation and reconstitution of the coenoses, which during a long period are used for haying and pasturage formed on the site of earlier cut timber stands at the boundary with the extrazonal steppe. During last decades, a gradual forestation of these territories is observed, the steppe plants species in the soil cover are replaced by forest species characteristic for the light-coniferous taiga. On the site of cuttings of dark-coniferous taiga in the first half of the last century in the southern part of Pre-Baikal, forests form with dominance of more hydrophilic trees species in undergrowth and young growth – fir and spruce replace cedar everywhere. This is probably due to secular forests dynamics with replacement of forest forming trees species on the background of climate changes during last decades. There are as well changes in the species composition of plants on the soil cover of forming dark-coniferous taiga.

Regularities of Vertical Propagation Mammals of the Mountain Massive Munku-Sardyk

The Munku-Sardyk mountain range is an important link in the Eastern Sayan mountain system, performing a barrier and refugial role for various mammalian species, in the transition zone between the Central Asian steppe and the Siberian taiga. Thus, the southern steppe slopes are the northern limit in the distribution of the Tuvan and Mongolian voles, Tarbagan marmot, tolai hare, mountain weasel and manul. For the Altai mole, brown bear, sable, Siberian musk deer, reindeer and elk, the southern border of their distribution lies in the forest zone of the Khubsugul region. The paper presents the basic information about the features of the vertical distribution of mammals on the southern and northern slopes of the massif. The complex structure of the vertical zonation of the mountain range and the harsh habitat conditions are of paramount importance in the distribution and number of mammals inhabiting it. The species composition of communities in five high-altitude belts is presented: forest-steppe, mountain- taiga, subalpine, alpine and nival. A comparative analysis of the degree of similarity of mammalian communities, depending on the altitudinal zonality and exposure of the slope, using the Jaccard coefficient, based on the analysis of qualitative data, has been carried out. A high degree of similarity of the lower belt with the higher one was revealed on both slopes of the mountain range. The highest degree of similarity between the mountain-taiga and subalpine belts was noted, and the lowest degree was observed in the forest-steppe and nival belts that were separated from each other. The low species diversity in the nival belt is associated with the harsh habitat conditions associated with the absence of protective feeding stations and mechanisms of adaptation to hypoxia in most mammals living in the lower part. When comparing the community of mammalian faunas between the belts of the southern and northern slopes, a high similarity of mountain-taiga belts and a decrease in the proportion of common species with height were noted. The obtained information eliminates the existing gaps in the territory poorly studied in the zoogeographic plan and makes it possible to form a unified environmental policy in the transboundary region.

Pyrogenic Transformation of Geosystems of the Western Cibaikalia: Factors, Conditions, Current State

The factors of pyrogenic impact on the taiga geosystems of the Western Baikal region against the background of the modern transformation of the global atmospheric circula-tion are studied in the paper. The results of world scientific research on modeling climate change and related adverse weather phenomena (prolonged droughts, thunderstorm activity, etc.) are presented. The natural factors contributing to the increase in the pyrogenic transformation of geosystems are described. The study of the spatio-temporal distribution of fires is carried out on the basis of data from remote sensing of the Earth. Information about unfavorable weather conditions and dangerous hydrometeorological phenomena, data on atmospheric phenomena (thunderstorm activity), daily values of air temperature and soil temperature under natural cover at different depths are analyzed in order to factorial analysis of forest fire sources in the study area. The characteristic of the current stage of geosystems is given based on field research conducted in June 2020. It was revealed that catastrophic fires registered in the study area in 1997 and 2015 occurred against the background of minimal thunderstorm activity. At the same time, in the central part of the Western Baikal region thunderstorms were the leading factor in the 2015 fires. Five years after the fire, the restoration of mountain taiga light coniferous forests is characterized by the predominance of the community of Chamaenerion angustifolium (L.) Scop. The successional dynamics of the geosystems of mountain taiga dark coniferous forests is going through the Betula rotundifolia Spach. with Ledum palustre L. and cereal-forb ground cover. Undergrowth of tree species (mainly pine) is rare and uneven about 800–1200 specimens per hectare.

Transformation of Geosystems of the Northern Part of the Baikal Natural Territory (Research and Mapping)

The features of transformation of geosystems of the north-western part of the Baikal natural territory are considered. The transformation of geosystems is considered in the context of changes in their essential properties as a result of the manifestation of transformative dynamics and evolution. It is established that the modification of the geosystems of the region was largely caused by the horizontal compression of the earth's crust, which is characteristic only for this section of the Baikal rift zone. This led to the formation of the Pre-Baikal Depression between the Siberian Platform and the Baikal Ridge. The combination of geodynamic regimes of the weakly active platform and the area of continental rifting caused an ambiguous response of geosystems to climate change. The development of contrasting types of geosystems is revealed-from high-grass fir trees to swampy woodlands of larch with cedar elfin. In the physical and geographical conditions of the area, the strict subordination of geosystems to the higher structure is violated. As a result, unique geosystems are concentrated here. They combine in their composition the components peculiar to the physical and geographical regions of Siberia and the Far East. Plant communities of various formations are represented here. Geosystems at the regional level of the organization are subject to transformations. The basic techniques of mapping the transformation of geosystems are considered. Mapping involves solving three main tasks, which are traditionally defined as the identification, systematization and interpretation of geosystems. They consist in the definition of diagnostic features of geosystems; the synthesis of time and space in a single whole, taking into account regionaltypological specifics, structural-dynamic and evolutionary transformations.

The Nature of Self-Organization of Geosystems of the Southern Baikal Region

In modern geographical research, the study of transformations of geosystems occupies a special place, corresponding to the current stage of development of scientific knowledge. The study of the transformation of geosystems is based on the features of selforganization of geosystems – through the manifestation of connections and internal mechanisms, parts merge into a single space-time whole. The article presents the results of the study of the nature of self-organization of geosystems of the Southern Baikal region, which reflects the whole complex of its factors, that were formed and transformed in the process of formation of physical and geographical conditions of the territory. Their identification took into account the methodological principles of self-organization research, the features of geosystems of the region, the nature of tectonic processes, various data on climate, soils, petrological composition of rocks, permafrost, the history of the development of components of geosystems and comparison of similar landscapes. To characterize the self-organization of geosystems in the research area, the following factors were considered: inter-component relationships, interaction with the environment, and the resonance of processes. As a key area for the study, the territory of the Southern Baikal region was taken within the northern macroscline of Khamar-Daban, facing the lake Baikal, from the Khara-Murin river to the river Snow. On the basis of data synthesis, a map of the key site is compiled, which shows the nature of self-organization of geosystems, which manifests itself in three types. The first characterizes the harmonious development of the geosystem, its preservation and restoration after external influence. The second type, which is characterized by rigid relationships of components of geosystems, is associated with stagnation in the development of the geosystem, the preservation of existing relationships. The third type is determined by the destruction of inter-component and intersystem and the formation of new discrete relationships of geosystems. Within the Southern Baikal region, there is a change in the self-organization of geosystems, accompanied by the formation of rigid and discrete relationships. Anthropogenic impact reinforces the existing trends, creating conditions for rapid, often irreversible transformations of geosystems.

Features of Transformation and Self-Organization of Mountain Nival-Glacial Geosystems

The Munku-Sardyk mountain range (3,491 m) represents the territory of the modern glaciation of The East Sayan. Different forms of transformation of nival-glacial geosystems have been preserved in this range. The processes of transformation and self-organization of geosystems are considered on the example of the Radde glacier and the unique stone glacier. Due to climate change, the glacier has shrunk considerably. Its area has decreased over 100 years from 0.3 to 0.19 km2, and over the last 20 years from 0.19 to 0.09 km2. However, the glacier has processes of self-preservation, slowing down the process of melting the glacier. This transformation of the glacier is manifested as the reservation of surface moraines. The peculiarities of the formation of surface moraines are considered. In the past century, the formation rate of moraines was 0.001 km2/year. Recently, the rate of formation of moraines has increased to 0.02 km2/year. In the second case, the unique stone stream (stone glacier) is an example of the transformation of the classical glacier into a new structure, which at this stage does not depend significantly on the observed warming, and can exist as an independent object for quite some time. The material is supplied by the rock of mountain range, and the transport by the ice bed is formed in winter from groundwater at the level of indigenous rocks, like subsurface ice. The structure of this stone stream is presented as an independent geosystem. It is assumed that the nival-glacial geosystems behave like lag systems. From the analysis of freezing and thawing of soils it follows that the increase and degradation of glaciers should be subject to the law of hystiresis.

Dust-Fraction of Granites, Migmatites, Marbleized Limestones, Ophiocalcites as a Carrier of Nanosized Dust Particles

In this work, we will discuss the study the dispersed composition stone dust such industrial objects as deposits migmatites, granites, marbleized limestone and ophiocalcites. The dust-like fraction the listed rocks is considered and evaluated as a micro-sized and nanosized component their structure formation. The main regularities of the formation nano- and microdust particles have been determined by the method membrane filtration. The most promising feature membrane filtration for the separation of professional (stone) dust mining quarries has been developed, which must be taken into account when developing a technology for processing raw materials, when separating particles into fractions for further use in the production the final product, when standardizing and qualitatively assessing the effect a nanosized fraction on the human body and environment. As a result the experiments carried out, the dispersed composition the rocks extracted at the quarries raw materials in the Irkutsk region was analyzed. The percentage particles with dimensions from 0.05 to 10 microns in the studied samples of professional dust was determined. The presence nanosized particles in them was confirmed, which, in turn, are the carrier a negative component, which can be considered from the point view industrial safety and health protection miners as a factor in the development such occupational diseases.

Particularities of Vertical Displacements Along the Delta Fault During the 1862 Tsagan Earthquake on Lake Baikal

Based on the ground penetrating radar, geological and morphostructural data, the particularities of single-event vertical displacements in Holocene sediments of various competencies along the land and underwater segments of the Delta fault activated on January 12, 1862 during the M ~ 7.5 Tsagan earthquake (southeastern side of the Baikal rift.). It is shown that the slip determined from the scarp morphology and the position of the main rupture in the section reflects the total displacement value, which is the sum of the brittle and plastic deformational components. The presence of water-saturated poorly consolidated sediments in the geological section increases the contribution of the plastic component. In this case, the width of the rupture zone increases. Despite the fact that the northeastern segment of the Delta Fault was submerged in the water of Proval Bay, the largest seismotectonic displacements occurred between the villages of Kudara and Sherashevo and on the outskirts of the village Dubinino in the land southwestern part of the structure, where the total displacement was 9,59 and 9,28 m, respectively. No such depths were recorded in Proval Bay after the earthquake. Along the Delta Fault under water, seismotectonic displacements were relatively small with a rather significant contribution of the plastic component from 26 to 53 %. This slip was a trigger for the seismic- gravity subsidence of the bay and sediment compaction, which continues to this day, judging by its almost unchanged depth since 1862 and the proximity of numerous seismic events, including the last Мs = 5.4 09.12.2020 earthquake happened on December 9, 2020 and strongly felt in Irkutsk.

Hydrological Regime of the River When Changing the Landscape Structure of the Catchment Area (by the Example of the River Goloustnaya)

The main features of the hydrological regime of the river are strategic regional characteristics. At the same time, a significant effect on surface and groundwater runoff, evaporation and transpiration determines the landscape of the transformation of atmospheric precipitation entering the drainage area, surface and groundwater runoff. The existing basin landscape structure has hydrological properties that change when structural components are disturbed. The article examines the relationship between the intra-annual regime of the river and changes in the landscape structure of the catchment area over ten years. An estimate of the size of landscape transformations is proposed based on data on global changes in forest cover in the world in the 21st century – high-resolution global maps of changes in forest cover in the 21st century. The analysis of the dynamics of characteristics of runoff, precipitation and area landscapes is carried out. The dependence of the hydrological regime of the river on the structural transformations of the drainage landscape was revealed for the phase of the upper rainfall runoff. An increase in water discharge in the river against the background of total precipitation was noted, which indicates a change in the landscape-hydrological properties of the catchment. As a result of the reduction in the areas of dark coniferous landscapes, which have significant runoff- regulating functions of the territory of the hydrological regime, the values and amplitudes of the rises of rain floods increase. Investigations of landscape-hydrological transformations of watersheds is an important direction in optimizing the use of natural resources in watersheds and minimizing the negative impact of natural waters.

Modern Transformations of Geosystems of the Western Macroslope of the Barguzin Ridge

Forest fires are one of the most important environmental factors affecting the environment. Due to climate change and the increasing frequency of forest fires, studies of the consequences of forest fires and the processes of restoration of disturbed geosystems are relevant. Over the past 20 years, there has been an increase in the frequency of fires on the territory of the Republic of Buryatia as a whole, and the western macro slope of the Barguzin ridge in particular. The situation is aggravated by the fact that a significant part of the fires occur in hardto- reach areas of the ridge, which complicates their elimination. The paper presents the results of observations (2015-2020 years) on the impact of forest fires on the taiga geosystems of the western macroslope of the Barguzin ridge. The features of post-fire restoration of geosystems are considered. The natural restoration of forests depends on the nature of the forest growing conditions and the ecological characteristics of the stands. Restoration of dark coniferous-taiga geosystems, including relict ones, after intense fires has not been revealed, since forest growing conditions are changing. The relevance of the research is also related to the fact that the western macroslope of the Barguzin Ridge is located within the Baikal Natural Territory (BPT), where protected areas are located and it is not uncommon for fires to disrupt relict geosystems that are under protection.