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On the background of climate dynamics during last decade, the Baikal Region manifests considerable changes in the whole biota structure. It is seen in the structural-dynamic organization, trends of forests development due to considerable variability of vertical and horizontal structures in the coenoses. Especially this is characteristic for the forests formation at the contact of different environments – at the boundary of zonal vegetation types and height belts in Pre-Baikal. Projects of protective forests in the basins of the rivers flowing into Lake Baikal in forests management for water protection and establishment of forests site under special protection within near-shore protective shelter belts excludes industrial forest cutting and limits other forms of forests use. Accounting of environment protection functions of forests at forests management and establishment of validity categories (not only for utility) will allow to stabilize hydroregimes and functioning of Lake Baikal basin’ ecosystem in the whole. [ABSTRACT FROM AUTHOR]

Studies of the peculiarities of vegetation structural-dynamic organization on post-agrarian landscapes in the Western Trans-Baikal allowed to establish modern trends of reconstitution of grasses (in the steppes) coenoses and the vector of formation of forest ones (at the initial stage of development) during last decades - since lands ploughing up for agricultural plants and use of the territories for pasturage had stopped. Land use in a region with relatively dry periods during different years at elevated anthropogenic pressure results in considerable destructions of soil and vegetation cover. The studied area is situated within the most important biogeographic boundaries, within the boundaries of regions and provinces of southern boreal forests and zonal dry bunchgrass steppes of Central Asian type. Degrading of the environment under such conditions is more manifested and vegetation reconstitution here is a long process in time and space. Recently there are trends of forests reconstitution on the lands ploughed up before and in the sites used during many years for pasturage. Steppificated spare stands of pine with cereals and motley grasses form, this is initial stage of forests of zonal type formation. There can be a constraint of forests formation on the fallows such as probable increase of anthropogenic impact, mainly pasturage accompanied periodically with burning (fire) on the background of climate changes determining the vector of formation of environmental conditions in the whole region. [ABSTRACT FROM AUTHOR]

The peculiarities of structural-dynamic organization of phytocoenoses at the contact of forests and extrazonal steppe are found out. The studied area is characterized by light-coniferous forests and by extrazonal (depression type) steppe cenoses forming on the valley bottom and along its boards and slopes trails of different expositions. The phytocoenoses of such habitats were used for a long period for pasturage and their considerable part was ploughed up for agriculture in the first half of last century. Nowadays they are mainly not used - these are fallows. It is noticed that during last 25-40 years, forests form steadily on the fallows and territories used before for pasturage. This is mainly due to changing environmental conditions as well as with the character of anthropogenic impact such as pasturage, ploughing up, cutting and fires during last decades. Formation of light-coniferous forests of zonal type is characteristic for the whole Tunka valley. [ABSTRACT FROM AUTHOR]

The phytocoenoses of environments contact in the Pre-Baikal reflect modern trends of formation and development of vegetation on the territories under concrete hysic-geographycal conditions in the different areas of Baikal region at all. The Selenga R. Basin, including surroundings of Lake Gusinoe, is within most important biogeographic boundaries, ones of areas and proivinces of southern boreal forests and zonal dry bunch-cereals Central Asian steppes, where zona forest-steppe is formed, the processes of environment degradation are more considerably expressed. [ABSTRACT FROM AUTHOR]

We present here the results of studies of the structure and trends of forests formation in the zone of the transition of polydominant dark-coniferous - light-coniferous forests into dark-coniferous taiga, as well as at the contact site of forest and sub-goletsy belts and mountain tundra in different Pre-Baikal areas. The main structural and spatialdynamic peculiarities of forest communities structure reflecting different forms of the development of forest vegetation surrounding Lake Baikal are given. [ABSTRACT FROM AUTHOR]

Studies of vegetation in the basin of the upper current of the Chona R. (a tributary of the Lena R., Irkutsk Region, East Siberia, Russia) were performed within activities on engineering ecology survey on the territory of Upper Chona oil-gas condensate mine (hereinafter - mine). The aim of these activities was to reveal and to estimate the modern state, injury and development forecast of the forests (and of the vegetation as a whole) within the mine since 1994, year of survey start. For this aim, a detailed analysis of available (archives) materials (forests taxation maps and others) was performed. Characteristics of structural-dynamic organization of forest communities in mine surrounding area and at the sites of wholes of different years of conservation reflects the vector of forests reconstitution. The conditions of ecotopes of phytocenoses for each concrete hole were taken into account. Primary forecast of probable vegetation destructions at further increase of technogenic impact is shown as well. [ABSTRACT FROM AUTHOR]

The work performed allowed to reveal specific pine forests (Scotch pine) with undergrowth of pine (Pinus sylvestris L.) and cedar (Pinus sibirica Du Tour) forests. The underwood of these forests consists of Daurian rhododendron (Rhododendron dauricum L.), blueberry (Vaccinium uliginosum L.), marsh tea (Ledum palustre L.). The general structure of the soil cover of the research area consists of cowberry (Vaccinium vitis-adaea L.), crowberry (Empetrum nigrum L.), multifoliate Andromeda (Andromeda polifolia L.), cranberry (Oxycoccus microcarpus Turcz. ex Rupr.), fescue grass (Festuca lenesis Drobov), bush grass (Calamagrostis neglecta (Ehrh.)Gaertner.), garden burnet (Sanguisorba officinalis L.), field horsetail (Equisetum pratense Ehrh.) with inclusion of such mosses as Schreber plevrotium (Pleurozium shreberi (Brid.) Mitt.), pigeon-wheat moss (Polytrichum juniperinum Hedw.) and hexagonal (Polytrichum sexangulare Brid.), polypody dicranum (Dicranum polysetum Sw.), ptilium pectinate (Ptilium crista-castrensis (Hedw.) De Not), Muehlenbeck's dicranum (Dicranum muehlenbeckii B.S.G.) and such peat mosses as Sphagnum palustre and Sphagnum fuscum in different variants of the species in the plant communities. The second synfolium contains Siberian cedar (Pinus sibirica Du Tour), rarely - spruce (Picea obovata Ledeb.) and Siberian fur (Abies sibirica Ledeb.). The cenoses include as well Pinus pumila (Pallas) Redel and weeping birch (Betula pendula Roth), white birch (Betula pubescens Ehrh.) and Asian white birch (Betula platyphylla Sukaczev) synusially in different quantitative variations in the phytocenoses. Such cenoses are formed on eolian sands along the eastern coast of Lake Baikal, from the Selenga R. delta (Oblom Cape) to Gramyachinsk settlement including isolated sited of the pre-coastal area of Chivyrkuy Bay where they occupy a narrow nearcoastal line at the slopes aprons. [ABSTRACT FROM AUTHOR]

Abstract  As a result of monitoring spatial changes in the cenotic structure of plant communities at the taiga-extrazonal steppe boundary on the western coast of Lake Baikal, models of taiga-steppe communities reflecting the formation, dynamics, and genesis of forests in the taiga zone have been constructed. Changes in the species composition of communities, mesophytization of steppes, the expansion of moss synusiae characteristic of polydominant dark conifer and light conifer taiga forests, active forest invasion into steppe areas, and the presence of dark conifer tree species in light conifer forests have been revealed. [ABSTRACT FROM AUTHOR]