Natural conditions of the formation of the monument of Maly Gonbinsky Kordon-2 of the Odintsovo Culture of Altai in the 4th–8th centuries A.D.

The study is aimed at reconstructing the natural and climatic conditions of the Upper Ob River region (south of Western Siberia) in the early Middle Ages (4th–8th centuries A.D.), based on the paleosol data obtained from the fortified settlements of Maly Gonbinsky Kordon-2/11 and Maly Gonbinsky Kordon-2 / 6-3. Settlements are located on the terrace of the right bank of the Ob River. The fortification elements are represented by a horse-shoe-shaped system of a ditch and a rampart, adjacent to the edge of the above-floodplain terrace, inside which there were dwellings and outbuildings. Archaeological investigations of the settlements permitted to study the sediments of the first terrace above the floodplain and to select core samples for palynological analysis. Applica-tion of this method allowed reconstruction of the vegetation during the occupational period of the complex of monuments MGK-2. For interpreting of the actual data, the method of landscape analysis was employed. The need for its application for carrying out paleogeographic reconstructions is warranted by the presence of the relict elements in the morphological structure of the landscapes. To establish their paleogeographic status, within the framework of this study, there was determined the percentage ratio of the amount of pollen and seeds of plants extracted from the deposits of the first above-floodplain terrace, corresponding to the existence of the Odintsovo Culture and belonging to different ecological groups. As the result, the dominance of sparse birch forests and forb dry meadows in the landscape structure of that time was established, whereas the vegetation associations featu-ring pine forests were in the status of progressive elements of the landscape structure. Also, supersedence of birch forb forests by green moss pine forests was revealed. The use of the landscape approach allowed recon-struction of natural conditions of the territory occupied by the complex of fortified settlements of MGK-2. On the basis of the digital elevation model, 3D visualization of the surface of the sediments overlapping the cultural layer of the monuments was rendered, which shows the location of the objects at the lowest elevations of the surface I above the floodplain terrace and the effects of the surface water flow. This necessitated construction of a drai-nage system, the main elements of which might be represented by shallow ditches.

Phytoplankton as an indicator of the current ecological status of the Ob River

The species composition, taxonomic structure, and the dominant complex of algae, and the distribution of phytoplankton abundance in the studied watercourse were identified based on data obtained for phytoplankton from the Ob River (from Tomsk to Salekhard) in summer 2019. Green algae (division Chlorophyta) make up the basis of the phytoplankton abundance in the river. The dominant complex is represented mainly by centric diatoms (genera Aulaсoseira, Cyclotella, Stephanodiscus) and non-heterocyst forms of cyanoprokaryotes (genus Aphanocapsa). The numbers and biomass of phytoplankton gradually decrease downstream of the Ob River; below the confluence of the Irtysh River, the edge effect occurs: increase in the diversity and density of organisms at the boundaries of ecosystems. Compared to the previous studies, the proportion of green and euglena algae, and cyanoprokaryotes in the taxonomic spectrum of phytoplankton increased, the composition of the dominant complex enriched, including due to non-heterocyst forms of cyanoprokaryotes, and the trophic status of the river increased to the category of eutrophic waters.

Improvement of methods of hydrological forecasting using geoinformation technologies

This article discusses the possibility of improving hydrological forecasting methods based on a neural network. The hydrological series, its importance and forecasting features are considered. For hydrological forecasting using the MapInfoProfessional geoinformation system, an electronic map has been developed containing information about the rivers of Russia, as well as gauging stations on the Ob River. The electronic map is the basis for creating a module for short-term hydrological forecasting based on an artificial neural network. The features of a neural network, methods of its training and implementation are considered. The developed artificial neural network is a layer of neurons with a linear activation function and a delay line at the input. To predict the levels of hydrological series, real water levels at gauging stations of the Ob River in the Novosibirsk region will be used. The developed module and its capabilities have been tested. The study was carried out on the basis of models of hydrological series, as well as on the basis of levels of real hydrological series. Based on the study, dependence of the root-mean-square error on the number of previous values of series was revealed. The study also shows that it is possible to use a neural network for the current one-step forecasting of levels of hydrological series in conditions of insufficient information about the runoff region and its characteristics.

ON THE STRATIGRAPHIC SIGNIFICANCE OF THE LOW TERRACES OF THE SUZUN STRATA OF THE UPPER OB RIVER REGION

Studies of the end of the 20th century showed that there are no sediments of the glacial-dammed lakesea, as well as sediments of periglacial alluvium in sections of low terraces of the Upper Ob River region, known as the Suzun Strata. The lower stage of terraces is composed of alluvial sediments, and the upper one is epresented by subaerial complex, which includes both deluvium and aeolian deposits. The height of areas varies significantly and is predetermined by thickness of the subaerial complex in each particular area. Сonsequently, the geomorphological principle does not work when differentiating the Suzun Strata into heterochronous geological bodies of accumulative terraces above the flood-plain.

Influence of Forest Environment Factors on Ornithocomplexes of the Valleys of the Large Tributaries of the Ob River (Western Siberia)

Western Siberia is an interesting polygon for studying the patterns of territorial variability of zonal forest formations and their animal population. Forests covering more than 60% of the territory are undergoing significant anthropogenic transformation due to the activities of the oil-and-gas industry, large-scale deforestation and fires. All this makes it very relevant to study the spatial differentiation of ornithocomplexes, as well as natural and anthropogenic environmental factors that determine it. The data was collected during the period of 1996-2010 using the route bird census method in 64 landscape forest plots with a total length of over a thousand km, in the valleys of large tributaries of the Ob River (the Chulym, Ket, Vasyugan and Tym Rivers). The total abundance of birds, the composition of the dominant species in terms of population density, and the species richness depending on the zoning (middle and southern taiga subzones), the species composition of tree stands, the terrain, and the degree of anthropogenic transformation of the environment by forest cutting and fires of forest ornithocomplexes, are discussed.

BARLEY YIELDING CAPACITY INDICES BY PRE-SOWING SEED TREATMENT WITH BIOLOGICAL PREPARATIONS

The use of high-quality seeds in the production process of cropgrowing is one of the main criteria for obtaining a good harvest. The research goal is to study the effect of pre-sowing seed treatment with biological preparations on barley yield formation under the conditions of the Altai Re-gion’s Ob River area. The research was carried out in 2019 and 2020 in the Altai Region’s Ob River area. The research target was the Vorsinskiy barley variety and the biological preparations used for pre-sowing seed treatment. The ex-periment included 10 variants; of those 4 variants using biological preparations obtained based on processed agri-cultural and woodworking wastes, and top peat processed by autohydrolysis-explosion. The control consisted in seed treatment with distilled water. The results obtained showed that the use of biological preparations in barley cultivation had a positive effect on the final result -crop yield. The average results over two years of testing showed a wide range of yield variations in the experiment variants. The yield values varied from 2.15 t ha in the Variant no. 8 to 2.82 t ha in the Variant no. 5; the control -2.60 t ha. The yield value in the Variant no. 5 with the use of top peat preparation was the maximum in the experiment. On aver-age, over two years of research, the variability in the vari-ants was from the medium of 10% < Cv < 20% in the Vari-ants no. 2, 3, 4, 5, 7 to high Cv > 20% -Variants no. 6, 8, 9, 10. The maximum positive effect on the yield formation of the Vorsinskiy barley variety is exerted by pre-sowing seed treatment with the preparations based of plant residues (sunflower husk, oat chaff -Variants no. 3, 4), woodworking wastes (pine needles -Variant no. 2) and top peat (Variant no. 5) processed by autohydrolysis explosion.

Landscape, Soil, Lithology, Climate and Permafrost Control on Dissolved Carbon, Major and Trace Elements in the Ob River, Western Siberia

In order to foresee possible changes in the elementary composition of Arctic river waters, complex studies with extensive spatial coverage, including gradients in climate and landscape parameters, are needed. Here, we used the unique position of the Ob River, draining through the vast partially frozen peatlands of the western Siberia Lowland and encompassing a sizable gradient of climate, permafrost, vegetation, soils and Quaternary deposits, to assess a snap-shot (8–23 July 2016) concentration of all major and trace elements in the main stem (~3000 km transect from the Tom River confluence in the south to Salekhard in the north) and its 11 tributaries. During the studied period, corresponding to the end of the spring flood-summer baseflow, there was a systematic decrease, from the south to the north, of Dissolved Inorganic Carbon (DIC), Specific Conductivity, Ca and some labile trace elements (Mo, W and U). In contrast, Dissolved Organic Carbon (DOC), Fe, P, divalent metals (Mn, Ni, Cu, Co and Pb) and low mobile trace elements (Y, Nb, REEs, Ti, Zr, Hf and Th) sizably increased their concentration northward. The observed latitudinal pattern in element concentrations can be explained by progressive disconnection of groundwaters from the main river and its tributaries due to a northward increase in the permafrost coverage. A northward increase in bog versus forest coverage and an increase in DOC and Fe export enhanced the mobilization of insoluble, low mobile elements which were present in organo-ferric colloids (1 kDa—0.45 µm), as confirmed by an in-situ dialysis size fractionation procedure. The chemical composition of the sampled mainstream and tributaries demonstrated significant (p < 0.01) control of latitude of the sampling point; permafrost coverage; proportion of bogs, lakes and floodplain coverage and lacustrine and fluvio-glacial Quaternary deposits of the watershed. This impact was mostly pronounced on DOC, Fe, P, divalent metals (Mn, Co, Ni, Cu and Pb), Rb and low mobile lithogenic trace elements (Al, Ti, Cr, Y, Zr, Nb, REEs, Hf and Th). The pH and concentrations of soluble, highly mobile elements (DIC, SO4, Ca, Sr, Ba, Mo, Sb, W and U) positively correlated with the proportion of forest, loesses, eluvial, eolian, and fluvial Quaternary deposits on the watershed. Consistent with these correlations, a Principal Component Analysis demonstrated two main factors explaining the variability of major and trace element concentration in the Ob River main stem and tributaries. The DOC, Fe, divalent metals and trivalent and tetravalent trace elements were presumably controlled by a northward increase in permafrost, floodplain, bogs, lakes and lacustrine deposits on the watersheds. The DIC and labile alkaline-earth metals, oxyanions (Mo, Sb and W) and U were impacted by southward-dominating forest coverage, loesses and eluvial and fertile soils. Assuming that climate warming in the WSL will lead to a northward shift of the forest and permafrost boundaries, a “substituting space for time” approach predicts a future increase in the concentration of DIC and labile major and trace elements and a decrease of the transport of DOC and low soluble trace metals in the form of colloids in the main stem of the Ob River. Overall, seasonally-resolved transect studies of large riverine systems of western Siberia are needed to assess the hydrochemical response of this environmentally-important territory to on-going climate change.

Landscape, Soil, Lithology, Climate and Permafrost Control on Dissolved Carbon, Major and Trace Elements in the Ob River, Western Siberia

Assuming that climate warming in the WSL will lead to a northward shift of the forest and permafrost boundaries, a &ldquo;substituting space for time&rdquo; approach predicts an increase in concentration of DIC and labile major and trace elements and a decrease of the transport of DOC and low soluble trace metals in the form of colloids in the main stem of the Ob River. However, an unknown factor is the change in hydrochemistry of the largest southern tributary, the Irtysh River, which is impacted by permafrost-free steppe and forest-steppe zone. Overall, seasonally-resolved transect studies of large riverine systems of western Siberia are needed to assess the hydrochemical response of this environmentally-important territory to on-going climate change.

Modelling of the Ob river runoff under climat change

Modelling of the Ob river runoff under changing climatic conditions has been carried out. Three scenarios of climate change in the Ob river catchment area in 2021–2050 are proposed. It is shown that if the trends of changes in meteorological characteristics that began in the 70s of the XX century continue, or if they change synchronously, the Ob river discharge will not undergo significant directional changes.