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We discuss stratigraphic and correlational age modeling of the Baikal sediment record and summarize studies of paleoclimate records in cores from various regions of Lake Baikal. The available paleoclimate reconstructions attest to an abrupt strong Early Wurm glaciation in the Baikal region at the oxygen isotope substage 5d, (117-105 ka BP). This confirms the existence of an "additional" glaciation predicted for Siberia from paleoclimate modeling and suggests a regional mechanism responsible for the intensity of this glaciation, which was better pronounced in Siberia than elsewhere in the Northern Hemisphere.
The available data on the Early Zyrjanian glaciation in Siberia provide an insight into the space-time dynamics of the origin of the Early Wurm glaciation and can account for the discrepancy between a considerable (about 40%) increase in global ice volume at the substage 5d and the lack of physical evidence for glaciation from other regions of the Northern Hemisphere. Catastrophic events of the 5e/5d transition revealed in the Baikal sediment record and in other Siberian data indicate a significant role of Siberia in climate-forming processes in the Northern Hemisphere.

Two boreholes, BDP-96-1 (200 m thick) and BDP-96-2 (100 m thick), drilled at the top of the underwater Akademichesky Ridge at 53^o41'48''N and 108^o21'06'', gave two parallel cores which were dated paleomagnetically. The correlation of the paleomagnetic data with the global magnetic scale has shown the age of the sediments exposed at a depth of 200 m to be 5 Ma. The average sedimentation rate was constant, about 4 cm/ka. Earlier palynological studies of core samples from BDP-96-1 were performed at 2 m intervals, which corresponds to the period of ~45-50 ka. In this paper, we present results of a detailed palynological analysis of the upper 30 m of the core performed at 20 cm intervals (4-5 ka). The age of the investigated core from BDP-96-1 covers most of the Brunhes epoch. Taking into account the lost upper 630 cm, it matches the time range from 170 to 780 ka BP. Palynological analysis of the sediments from the range under discussion revealed 13 epochs in the development of the regional flora structure: seven epochs of predominance of forest plant formations and six epochs of its significant degradation. The epochs are correlated with the stages of changes in the volume of global ice, recorded in the marine oxygen isotope scale. It is difficult to determine the extents of the coolings, because spores and pollen are scarce in the sediments of these epochs. However, it is apparent that forests did not disappear from East Siberia during the coolings. All main arboreal species now growing there persisted during Pleistocene glaciations. The structure of the vegetative cover underwent profound changes. The areas occupied by forests decreased. Larch and spruce north-taiga forests were predominant under the humid cold conditions of the beginning of interglacials and the end of glaciations; they were then replaced by fir and cedar pine forests. Larch-pine and cedar pine middle-taiga forests expanded under the moderately warm and relatively dry climate of the mid-interglacials. Obviously, this was accompanied by a wide spread of steppe vegetation. A comparison of the frequency and habit of changes in vegetation type in the study region 170-780 ka BP with those in various regions of the Northern Hemisphere demonstrates that the East Siberian vegetation responded to global climatic changes synchronously with the vegetations of other regions.

Analyses of clay minerals have been performed on recent and ancient (age 900 years) sediments of the west-east trending Zavorotnyi transect in the North Basin of Lake Baikal (southeastern Siberia). The aim was to study clay minerals to identify the characteristics of the eastern and western sediments and to relate them to catchment areas or to sedimentation mechanisms. Apart from illite, which is the most abundant mineral along the transect, the clay mineralogy changes distinctly between the eastern and western sediments. The western clayey sediments are characterized by high chlorite contents, low smectite and kaolinite contents, and a general good crystallinity of all clay minerals. The eastern clayey sediments have lower chlorite contents, higher smectite and kaolinite contents, and poorer crystallinity of the clay minerals. We suggest that differences in the geological background and morphology of the catchment areas lead to these differences between the eastern and western surface elements as a result of different weathering and transport mechanisms prior to sedimentation. The smectite content and illite-chlorite ratio are possible indicators for differentiating between the western and eastern predominant sediments. From this interpretation it follows that western catchment areas supplied the turbidites accumulated in the center of the Zavorotnyi transect. The great variability in distribution of clay minerals over a few hundred years, most pronounced in the smectite content and illite-chlorite ratio, indicates significant changes in the factors controlling sedimentation in the North Basin. This must be taken into account when using the distribution of clay minerals in Baikal sediments for paleoreconstructions.

Rock-magnetic and granulometric studies were conducted on the BDP-93 cores (100 m in length) obtained from the Bugul'deika saddle of Lake Baikal, southeastern Siberia. The remanent magnetization of the cores shows dominant positive inclination, indicating that the cores are included in Brunhes normal chron ( 780 ka BP). Some geomagnetic excursions were found in both cores. With the age scale referred to ¹⁴C dates and regeression, they are estimated to be 100 and 120 ka BP (Blake event), 310 and 340 ka BP (Calabrian ridge, event 1). These geomagnetic events possibly include double excursions. Comparison of magnetic properties with the content of diatoms and biogenic SiO₂ shows a low concentration of magnetic minerals during interglacial periods and a high concentration during glacial periods. However, this relation is obscure at the lower 60 meters of the core. Rock-magnetic and other parameters suggest a change in sedimentation environment at a depth of 40 m, which may be related to a shift of the sedimentary source. These results suggest that the sedimentation environment of the Bugul'deika saddle was influenced by the local sedimentation conditions.

Depth profiles of carotenoids, chlorophyll derivates, and other biogenic indicators, such as biogenic silica (BGS), total organic carbon (TOC), total organic nitrogen (TON), and perylene, were measured in ¹⁴C-dated sediments ( 2m thick) sampled from the Southern basin of Lake Baikal. The photosynthetic pigments, BGS, and TOC (TON) accumulated in the upper part (80 cm) of the core (dated at 12-13 ka BP), whereas biogenic perylene occurs in its lower part (below 80 cm). Biogenic silica in the upper part shows a negative correlation with total carotenoids and no significant positive correlation with TOC and total chlorophyll a. This indicates that high contents of BGS providing oxidizing conditions in the lake stimulate aerobic decomposition of organic compounds in the water and in the surface sediments. The high concentrations of perylene in the lower part of the core against the background of the low lake productivity suggest specific processes of sedimentation in the past.

We have studied the relations of the composition of the solid runoff of rivers in the Baikal basin with mineralogy and geochemistry of bedrocks of recognized feeding petrographic provinces

Magnetic susceptibility was studied on short sedimentary cores (a few meters) from lakes Baikal and Biwa. Measurements of cores less than 1 m long showed that the Baikal samples have oblate anisotropy ellipses with nearly vertical short axes, whereas in the Biwa cores these axes are nearly horizontal and their oblate geometry is poorly pronounced. The difference in anisotropy of magnetic susceptibility of the cores from the two lakes may be due to different depositional environments (water depth at the sampling site in Baikal was 200 to 1600 m, and that in Biwa was a few tens of meters).
The magnetic susceptibility anisotropy increases down the cores and reaches a stable value at a certain depth. It shows a direct correlation with variations in water depth at sampling sites. The hydraulic pressure on the bottom sediments may be related to the depth of magnetic susceptibility saturation.
Magnetic susceptibility of the Ver-99 gravity core recovered on the opposite side of Lake Baikal in the Selenga pro-delta varies broadly in the age region of 11 to 12 ka, and anisotropic parameters show the same changes within these age intervals. The magnetic susceptibility of the Ver-97 st. 6 gravity core from the Akademichesky Ridge exhibits similar variations. The succession of magnetic susceptibility fluctuations is possibly related to the cooling event of Younger Dryas (11 to 12 ka BP). At that stage, a significant sediment transport may have occurred over a great area of Lake Baikal.
The age-dependent fluctuations in magnetic susceptibility in the Ver-97 core show a nearly perfect correlation with variations in ¹⁸

The basin analysis for assessing the status of groundwater on the Khovu-Aksynskii arsenide-cobalt-sulfide deposit (Tyva Republic) located on the left bank of the Elegest river was carried out together with field morphometric studies and hydrogeochemical sampling. It was determined that the chemical composition of groundwater is largely dependent on the basin organization of the territory. The structural indices of areas, lengths, slopes and bifurcation calculated for the Khovu-Aksynskii gully basin, and also the geomorphological work indicate that within its limits the functional type of the 3rd order basin components on removal and accumulation of water and lithodynamic flows changes from the denudation (in the upper component) to the accumulation (in the middle) and transition - in the integral lower component. In accordance with the type of basins, it has been established that the groundwater chemistry is formed mainly in the middle and lower components of the basin under natural and anthropogenic impact. With distance from the pollution sources, the halos are formed in the groundwater of deluvial-proluvial horizon, reflecting a decrease in the total mineralization (from 0.68 to 0.3 g/L), hardness (from 7.1 to 3.2 mg-eqv/L) and arsenic (from 0.013 to less than 0.005 mg/L). The absence of water pollution by ore-forming heavy metals (nickel, cobalt and copper) typical for the deposit and tailing dumps is also explained by the transitional type of integral component of the catchment basin. The results obtained show the possibility of using it in modeling the conditions for denudation and accumulation of natural and anthropogenic pollutants in the underground aquifers.

This article presents the results of the GIS analysis of the transport accessibility of regional centers for residents of Zabaikalskii krai with the central regional hospitals located in them. The analysis was performed in the ArcGIS environment using the authors’ approach and the custom tools created, such as models of geoprocessing processes. For analysis, we used official statistical information from the databases of Rosstat and Zabaikalkraistat, and data from the Ministry of Health and the Ministry of Construction, Transport and Road Facilities of Zabaikalskii krai. Based on the existing settlement systems and the road network, service areas consisting of “temporary” access zones determined by the time of travel by car were built for each central district hospital. The results of the analysis indicate the existence of spatial and temporal inequality for region’s residents in the possibility of obtaining medical services. It was found that more than half of the region’s settlements, that is, 82 % of the krai’s inhabitants, are located in the hourly accessibility zone by car. Twelve percent of the region’s population lives in settlements that are one to two hours away by car from the district centers. The acute problem is the availability of medical care for residents of the northern districts of the region. It has been established that residents of 69,3 % of settlements in the region are located remotely from official inter-municipal bus routes, their population can mainly rely on private and fixed-route taxi or their own transport. Therefore, even for those living in the hourly accessibility zone, the ability to reach the district center can be a significant problem.

This paper presents an analysis of response of the ecosystem service value to land use/land cover (LULC) changes as well as of the spatial contribution from individual ecosystem service function changes of Barasat Sadar sub-division (West Bengal, India) during the period between 1977 and 2016 based on the modified coefficient. Landsat series satellite images were downloaded at about ten year’s intervals to envision occurrences in spatio-temporal LULC patterns. A supervised classification was performed based on maximum likelihood (MXL) classifier to identify the LULC characteristics. Ecosystem serviced value were calculated per hectares of the terrestrial ecosystem based on the coefficient of each land cover characteristics used in earlier research. The highest value of ecosystem service value was recorded for a surface waterbody in 2016 (477.06 million dollars) and the lowest value was estimated at 0.98 million dollars for fallow land. Our results suggest that deterioration in agricultural fallow, dense vegetation, scrub land and rapid expansion of crop land, and surface waterbody artificial infrastructure for the period of 1977-2016 led to an incessant loss of the total ecosystem service value to the tune of $238.92 million using the coefficient adopted in calculations. The outcome of the investigation can serve as a reference and basis for enlightening decision building concerning the management of land resources and subsidize to a trade-off between urban growth and the lessening in ecosystem services.