Cryogenic soils in the Vilyuy River Valley (Yakutia)

The object of this research is the cryogenic soils of the territory located in Central Yakutia, in the middle reach of Vilyuy River nearby Makhatta Tukulan with middle-taiga larch woods landscapes. In July 2021, on the right and left banks of the Vilyuy River, twelve soil sections have been formed, which relate to turf-podzols and turf-sub-units of the illovial-ferruginous, sod and alluvial sod, psammozems and stratozems according to to classification and diagnostics of Russian soils (2004). On the slope of the river valley was also formed the soil catena that included elementary geochemical landscapes of river terraces tops and slopes surfaces, as well as middle and high floodplains on the slopes of thermofusional funnels. Soil sections were also formed in flooded beam bottom and well-drained ravine bottom, on sub-horizontal Makhatta Tukulan surface, bottoms and  slopes of thermo-suffosional funnels. The study involves 46 soil samples for measuring the acidity level (pH), electric conductivity (EC), and concentration of total disolved solids (TDS). The explored soils are characterized with pH ranging from 2.81 to 7.78, with most common fluctuations of 5.5–5.6. TDS rates were often within the limit of 10 mg L-1 and rarely exceeded that threshold, however, there were single valyes higher than 50 mg L-1. Thus, the highest EC values (over 100 μS/cm) were measured in surface and subsurface horizons with high organic matter content, whereas mostly mineral horizons had typical EС values within the limit of 20 μS/cm.

Modelling the Structure of Terrestrial Landscapes in Urban Areas

The study of internal and external factors in the formation of an urban geosystem is determined by its complex structure and multiple connections. Based on geoinformation modelling, an analysis of the landscape structure of the city territory is carried out, which can be a basis for further geoecological research. Morphometric indicators, which make it possible to determine the elementary geochemical landscapes, are indicated according to the data of the digital elevation model. A standardised topographic position index (TPI) is used to determine locations. Spatial zoning according to the type of land use reflects the qualitative features of the external load and technogenic impact. The data on the composition of the lithogenic base show the properties of the depositing medium and determine the natural background. Number of categories of landscapes identified are 58, characterised by a homogeneous geological composition, technogenic load and conditions for the migration of matter. The ratios of various landscape zones have been calculated. The study area as a whole is characterised by the predominance of migration processes over accumulation.

ECOLOGICAL AND GEOCHEMICAL ESTIMATION OF THE SPREADING OF TECHNOGENIC ELEMENTS IN THE TERRITORY OF KIVERTSIV NATIONAL NATURAL PARK "TSUMANSKA PUSHCHA"

Analysis of heavy metals content in the soils of the territory showed its heterogeneous distribution and dependence on available sources of technogenic impact. Geochemical accumulation coefficients were calculated and analyzed. The highest concentrations of manganese and chromium are in soils developed on forest deposits. The highest concentrations of nickel and copper are in soils developed on water-glacial deposits. Most of the studied heavy metals exceed the regional geochemical background. In terms of gross content in soils, trace elements form the following geochemical series: Zn> Cu> Pb> Ni> Mn> Cr. Accumulation of lead in forest deposits up to 2-3 MPC was defined. Most heavy metals in the soil are nonuniformity distributed. High values of the variation coefficient (V) – more than 34 % – are typical for inhomogeneous set of data on the concentrations of all investigated heavy metals. The highest index of variation was defined for lead concentration and equal to 170%, the lowest values were obtained for chromium content and equal to 34 % and zinc – 36 %. In the investigated soils there are two types of micronutrient distribution: elements accumulation in organic horizons with concentration decrease in the lower part of the profile and distribution by sedentary – illuvial type. The first type is characterized by increasing distribution of the following elements Zn, Pb; the second one is characterized Co, Ni, Cu, Mn. The ecological and geochemical assessment of technogenic elements distribution of the NNP Tsumanska Pushcha territory is made on the basis of the comparison of technogenic geochemical specialization of different environments (water, soils, etc.). For assessing the role of landscape components in the general geochemical anomaly of the territory, it is proposed to create total ecological and geochemical estimations. It represents the total values of pollutant concentration coefficients in individual components. Further researchers should focus on the analysis of macronutrients and genetic types of soils; determination of the reference content of elements in geochemical landscapes for defining intensity migration and characteristics of elements distribution; conducting biogeochemical zoning.

Soils and landscapes as legacies of the sugar industry land use

<p>The sugar industry has been widespread in the world for centuries, accumulating huge amounts of production waste. The development of modern technologies for sugar beet processing has led to the abandonment of dumps and sumps; not all of them were remediated later. In Russia, the industrial production of sugar from sugar beets was established in the early 19th century. For the first time, soils and landscapes formed on abandoned sites of sugar production waste in the Chernozem zone of Russia were studied. The distribution and chronological sequence of abandoned sites were identified using space images and field observation. Sugar production wastes discharged into sumps and landfills contained mainly carbonic lime (СаСО3), caustic lime Ca(OH)<sub>2</sub> and organic material, and an admixture of nitrogen, phosphorus potassium and sulfur (about 1-3%). It was revealed that in about 50 years, alkaline soil- geochemical landscapes were formed, which are unusual in the study area. Series of ponds temporarily filled with rainwater – former waste sumps – are covered with dense reed beds (Phragmítes austrális); there, strongly alkaline (pH ≥9), rich in organic matter and bioturbated soils with a thickness of up to 50-60 cm are formed. They can be attributed to Garbic Technosols (Carbonic), but their classification position in WRB needs to be clarified. Reed has spread widely in the surrounding water bodies and rivers; newly formed landscapes enrich waters with nutrients, contributing to their eutrophication. Soil mantle is also complicated by Technosols of industrial sites of sugar factories, soils in the remediated and no-remediated landfills, and soils irrigated with sugar mills' wastewater. All these soils are repositories of large volumes of organic carbon. The study of newly formed soils and landscapes, overgrowing of dumps and sumps is extremely important both for nature conservation and for understanding the seasonal patterns of carbon dioxide emissions from accumulations of organic substances. Integrated soil-geochemical and geobotanical studies of areas affected by the sugar industry can be pioneers, among other things, to expand the horizons of soil and geobotanical classification.</p><p>The work was financially supported by the Russian Foundation for Basic Research, project № 19-29-05025-mk.</p>

LANDSCAPE AND GEOCHEMICAL CHARACTERISTICS OF THE BLACK SEA COAST OF RUSSIA

The article is devoted to the use of landscape-geochemical mapping to study the spatial structure of the Black sea coast of Russia. Landscape-geochemical map of Black sea coast of Russia is done as a result of a complex study of the South of Russia summarizing large volume of various materials geological, soil, geobotanical, geological trends and the official in the field work process. Topographical and geological maps of scale 1:200000–1:500000 were the basis for drawing up the map of geochemical landscapes. Using these data, it was possible to establish the main factors of landscape differentiation and make auxiliary maps that characterize the taxonomic parameters: 1-plant communities and types of nature management developed in the region; 2 – types of geochemical conditions in soils; 3 – geomorphological features; 5-soil-forming rocks. All these factors are taken into account at various taxonomic levels and are clearly shown on the map of geochemical landscapes. The area of the research area is approximately 8,300 km2 . The variety of natural conditions and the wide development of anthropogenic activities caused the complex landscape and geochemical structure of the studied territory Most of the territory of the Black sea coast of Russia is occupied by biogenic landscapes (5717.2 km2 or 69 %). Technogenic landscapes on the black sea coast of Russia are developed everywhere, but their largest area is on the Taman Peninsula and the area from Anapa to Novorossiysk. The map made it possible to assess the natural differentiation and specifics of the technogenic transformation of the studied territory. The objectivity of using the landscape-geochemical map as a basis for a comprehensive study of the territory is confirmed by the results of studying the features of migration and concentration of chemical elements in soils and rocks.