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A water-soluble silver nanoparticles stabilized by a unique polymer matrix - available natural polymer melanin Inonotus obliquus was synthesized for the first time. The melanin is a multifunctional polymeric matrix whose inherent high electron-ac ceptor ability, presence of stable free radicals in high concentrations pronounced semiconducting properties, and others. A syn thesis of nanoscale zero valent silver composite is the formation of colloidal silver metal particles from silver nitrate solution in the dispersion medium (aqueous alkaline solution of melanin). A sample of the nanocomposite was obtained as the form of a black-brown powder with a silver content of 5,4 %. The composite formation is self-organization of inorganic-organic polymer structures, including the regulation of hybrid fragments sizes on nanoscale level by specific adsorption of melanin on the surface of the growing inorganic nanoparticles. The bulk (as opposed to nucleus) melanin shell formed on particles prevents further ag gregation of nanoparticles, while giving them water soluble properties. The redox reaction of melanin matrix with silver nitrate occurs in the nanocomposite formation. The silver nanoparticle dimensions comprise 8-24 nm, with a predominant content of nanoparticle sizes of 16-22 nm. The silver-melanin nanocomposite thus obtained from renewable raw materials is promising for use in biomedicine and materials science, as there may be synergies pronounced antimicrobial activity of nanosilver with a unique protective (not only absorb different radiations, but also neutralize and detoxify harmful to the cells free radicals formed by the action of ionizing radiation and certain chemicals on living organisms) and the powerful antioxidant properties of melanin. Wherein the prolonged action to be expected due to the presence of the natural polymer matrix.

The results of optical absorption study of silver nanocomposites on a basis of arabinogalactan-oligopyrrole block-copolymer matrix with different length of oligopyrrole branches (1, 3, 10 chains), pure polypyrrole and also arabinogalactan that is natural polysaccharide of Siberian larch wood are discussed. Optical absorption study of silver nanocomposites with arabinogalactan oligopyrrole block-copolymer matrix showed the presence in spectra of three absorption bands that result from arabinogalactan end aldehyde groups, transversal and longitudial components of 0D and 1D nanosilver plasmon absorption. According to transmittance electronic microscopy data, nanocomposite of nanosilver and block-copolymer grafted matrix with unit ratio arabinogalactan-oligopyrrole 1:1 has 73 % of 0D nanoparticles with 21,3 nm mean size and 27 % of 1D nanoparticles with 28,7 nm mean length and 20,9 nm mean width. It was found that width of the arabinogalactan absorption band at 294 nm and plasmon absorption of 0D nanosilver observed for samples with unit ratio arabinogalactan-oligopyrrole 1:1 and 1:3 at 426 and 490 nm respectively increase and become considerably less evident, and the absorption band due to longitudinal component of 1D nanosilver plasmon resonance and polarons of nanocomposite matrix oligopyrrole branches shifts to longer wavelengths with growing the length of oligopyrrole branches (585, 754, 800 nm for the nanocomposite of 1:1 and 1:3 and 1:10, respectively). It was also demonstrated that optical absorption maximum of polypyrrole has long-wavelength shift owing to this conducting polymer passes into weakly doped state under influence of environment air.

Deterioration of the coastal environment of Lake Baikal is an issue of the day, which has been caused by the ongoing significant changes in the coastal benthic community, accommodating most of the endemic species of the lake inhabit. In-depth integrated studies of the coast and nearshore waters of the lake are required to specify the causes of these changes. The paper presents a geographic information system developed by the authors to support research into human impact on the environment of the coastal zone of Baikal Lake. The system is realized as a web geo-portal in the Internet and it allows the researcher to gen erate a common base of thematic and cartographical data within the project framework, as well as to perform start-up of Inter net services to tackle the challenges of geoprocessing and a comprehensive data analysis. The open architecture of the developed geoportal allows to expand its functionality by addition of the new services which are available both locally on the geoportal server, and far off on other servers. The supported standards in the field of geoinfor matics benefit the interoperability of the program systems realizing functions of the analysis and processing of geodata. A spe cific feature of the developed geoportal is an opportunity provided to users to independently operate with their data structures, and also to adjust the start of geoprocessing services, including those that require connection with the «Academician V. M. Matrosov» computing power cluster at the Irkutsk supercomputer center, Siberian Branch of the Russian Academy of Science». During the project implementation, the filling of geoportal with thematic and spatial data on results of the conducted research was carried out. The collected data allow to obtain integrated indicators containing information on the anthropogenic influences on the en vironment within a certain time interval.

We examine four stages of research into the Baikal natural territory (BNT) accomplished by the V. B. Sochava Institute of Geography SB RAS. The research efforts have been made in the form of combined observations at permanent and semipermanent stations, different-purpose field expeditions and scientific generalizations as well as by orders of administrative bodies and economic entities; results were published in the form of books, papers and maps. The methodology of landscape planning is adapted to the special conditions and restrictions for nature management around Baikal. An important development was official approval of the ecological zoning of BNT that was developed in the Institute. Territorial planning documents and tools furnished a clue to determine criteria for assessing the ecological admissibility of siting facilities used for economic and other activities in the central ecological zone of BNT, and to prepare scientifically grounded recommendations for governmental authorities and municipal bodies regulating the inclusion of results of this assessment in territorial planning schemes. Particular emphasis has been placed on the spatial patterns in the formation of the ecological situation throughout the territory of Baikal’s water area and drainage basin as represented in the “Ecological Atlas of the Lake Baikal Basin” thus providing a possibility of substantiating the directions of an ecologically balanced and sustainable territories development of Russia and Mongolia in the future. Furthermore, the studies revealed a need to take into consideration the existing contradictions and differences in the Baikal policy priorities between the global, regional and local levels of territorial organization of society.

On the basis of data from monthly bulletins of the Irkutsk Center for Hydrometeorology and Environmental Monitoring for June-August 2001-2013, we investigated the association of the atmospheric circulation with potential summer ablation of the glaciers of the Baikal Range. As the indicator of ablation, we used the accumulated positive temperatures calculated for the mean height of the glacier zone. The summer seasons were classified into three groups: with high, low and moderate ablation. The maximum and minimum values of accumulated positive temperatures, respectively, were 1152 (the year 2002) and 787 °C (2013). The HYSPLIT model was used to identify the prevailing directions of air masses over the study area: westerly, southwesterly, northerly, and northwesterly. We assessed the contribution from the meridional component of the atmospheric circulation which has been enhanced over the course of the last decade. According to the dynamics of A. L. Kats’ zonal and meridional circulation indices, there occur summer seasons with a maximal (2007 and 2010) and minimal (2003 and 2012) intensity of the zonal circulation as well as inter-annual variations in the meridional circulation. Results of a comprehensive analysis of ground-level and altitudinal synoptic maps, isobaric fields of absolute and relative topography, and the temperature regime over the glacier zone (NCEP/NCAR) revealed synoptic conditions contributing to an increase/decrease in glacier meltdown in the region under consideration. A study is made of the dynamics of frontal activity, the types of advection and of the warm wet air masses over the Baikal Range during summer seasons. A change in the frequency of all the circulation mechanisms used in this study involves a change in weather conditions and climatic regime, which favor an enhancement or a decrease in ablation for glaciers and has influence on the evolution of the entire glacier zone of the Baikal Range.

We examine the hydrothermal conditions (the Si index) for 1961-2010 in the natural landscapes of the Prebaikalian and Transbaikalian parts of the Baikal natural territory (BNT), including the respective shores of Lake Baikal. It is found that the driest months in the Prebaikalian and Transbaikalian parts, respectively, are May-June and June, when severe droughts occur in all natural landscapes. It is established that whereas the first two decades (1961-1970, and 1971-1980) were more humid, the last two decades (1991-2000, and 2001-2010) have been characterized by the driest conditions. The study revealed the occurrence of significant (p < 0.05) positive changes from May to September, pointing to an increase in the recurrence of droughts with a maximum in July. It is found that the Transbaikalian part of the BNT is characterized by a higher recurrence rate of droughts, and by larger (in magnitude) values of the Si indices. The period under consideration showed a change in the distribution of drought phenomena across time and space. The dry conditions encompassing more than half the BNT were observed prior to 1986 in separate months of the growing period or continuously during two months. Starting in 1986, there occurred drought periods three months long or longer. The highest recurrence rate of the dry years was generally observed across the territory after the 1990s. It is shown that excessive moistening has a discrete pattern of distribution.

On the basis of hydrometeorological data on Lake Baikal for a long period of time, an analysis is made of the lake level fluctuations, and their association with secular and intrasecular hydraulicity cycles. We provide generalizing indicators of the long-term range and intra-annual amplitude of level fluctuations and dynamics, and the dates of reaching minimum and maximum values under natural conditions and at the period of regulated flow. We expanded and updated information available for monthly indicators of the level, useful inflow into Lake Baikal and water discharge in the source of the Angara river for a long period of observations. The study identified the boundaries of secular and intrasecular cycles, high- and low-water years on Lake Baikal, and their characteristics for the historical (1747-1903) and modern (1904-2015) periods. A classification of hydraulicity was made by categories (normal, decreased/increased, low/high, extremely low/extremely high, and disastrous) according to the probability of useful flow into Lake Baikal, and its quantitative indicators were calculated for each of the categories. Emphasis is placed on the causes, characteristic features, problems and risks associated with low- and high-water periods. It is established that the aforementioned periods, as a rule, are the result of changes in the atmospheric circulation processes accompanied by positive/negative anomalies of summer temperatures and atmospheric precipitation across significant territories adjacent to the Lake Baikal drainage basin as well as by global changes of climate. We determined the main risk factor for the regulation of the Lake Baikal level at low-water periods, i. e. the need for the stable operation of the water intakes and the associated maintenance of minimum water flow rates in the tail race of the Irkutsk Hydropower Power Plant (HPP) (1300 m ³ /s) taking into consideration the minimum design marks of the water intakes. It is established that the risks of high-water periods are associated with the discharges of flood waters through the Irkutsk HPP, and with eventual inundations which under current conditions are unavoidable even in the case of water flow rates from 2800 to 3000 m ³ /s, and would lead to significant inundations in the city of Irkutsk in the event that the amounts of 4700-6000 m ³ /s are discharged through the hydroelectric scheme.

We suggest an integral scheme for assessing the water and sediment discharge in the rivers of the Selenga river basin, based on using expeditionary, network and model data. Assessments are made of the changes in streamflow and in suspended and tractional sediments of the river, and relevant regularities are revealed. A forecast is made of regional changes in water discharge due to anthropogenic development of the territory. It is shown that the expected flow regulation of the Selenga and its tributaries in Mongolia would lead to a reduction in the maximum mean monthly streamflow by up to 14-15 %, and to an increase in the minimum winter flow by up to 73-75 %. Evaporation losses of the discharge from the projected reservoirs, and the water intake for the flow transfer will correspond to a decrease in the water level in Baikal by as much as 1 cm/year. The possible transformation of the territory’s water balance as a result of anthropogenic changes in landscapes during mining operations is investigated in terms of the regional mesoclimate model COSMO_CLM.

We examine the influence of rifting processes on the location of the lakes along the eastern shores of Lake Baikal, and on the formation of chemical composition of the waters contained by them. It is determined that the lakes are in different geologo hydrological conditions. It is established that their water areas liberate gas mainly consisting of methane and nitrogen; increased content levels of helium were discovered in free gas in areas where deep-seated faults occur. Manifestations of mud volcanism associated with methane discharges were observed. It is shown that the faults serve as the vehicle to discharge into small lakes fissure-vein waters which impart a peculiar kind of geochemical appearance to the water, and thick deposits of sapropel were produced under the warming effect of thermal waters. In the lakes there is taking place a transformation of chemical composition along the soda direction. In the water body with a retarded water exchange, the mineralization of the waters exceeds 1 g/L. On the eastern shore of Baikal’s Southern Holow, fissure-vein waters are not discharged, chemical composition is formed as a result of drainage of the Kabanskii bog massif, and the waters refer to the hydrocarbonate magnesium-sodium-calcium type. The emissions of free gas on this territory are dominated by methane.

The methodology of studying the streamflow formation mechanism based on using natural chemical tracers is discussed. Presented are the results from adapting and testing the technique for separation of runoff hydrograph according to genetic components (sources of alimentation) built upon the use of natural chemical tracers in term of the End-Member Mixing Analysis (EMMA) model. By using the procedure of EMMA analysis, we generated two complex model tracers, each of which representing a linear combination of initial chemical tracers. Its core is comprised of the method of Principal Component Analysis. The methodology was used within the program of experimental investigations on a small basin of the Laninskii creek flowing nearby the coast of Lake Baikal. The contributions from the sources of alimentation of the creek’s runoff are estimated. They include the rain waters with an insignificant contribution, the waters of the subsurface soil horizon having a tendency toward a predominance at the low-water period, and so-called aufeis waters making a significant contribution during the flood formation. Prevailing ions of anion and cation composition, the value of electrical conductivity and content of total organic carbon can be used as reliable tracers. The modeling results are in good agreement with the qualitative views concerning the runoff formation on the study territory. A broad range of possibilities and the prospects of the procedural tools of tracer hydrology are demonstrated.