Gully erosion is the extreme process of the activity of temporary water flows on slopes, belongs to the category of exogenous natural hazards. An assessment of gully erosion in the area of intensive agriculture in Russia (in the steppe zone) is a topical task. It can be solved by using high resolution remote sensing data and GIS mapping. Geoinformation mapping of gullies and spatial and temporal assessment was carried out within a large region of Russia (Saratov region, 100.2 thousand km2 ). The choice of the study area is due to the dominance of steppe landscapes and to the lack of data on modern gully erosion. In this study, visual interpretation of remote sensing data was used to detect gullies and basin approach (704 basins of small rivers) was applied to map the results. The thalwegs of gullies was identified according to the formed system of interpretation signs of gully forms. The vector layer containing 17628 linear objects was created for the study area, and the classification of gullies into types was also carried out. The total length of the gully network in the Saratov region is 1612 km, where the average length of the gullies is 92 m. The majority of gullies (88%) belong to the slope type. More than 80% of the total area of the region is characterized by a weak gully density and the absence of gullies. The maximum values of the length density of gullies (up to 443 m/km2 ) are observed in the river basins of the Right Bank of the Volga River in the Saratov region, the minimum (more than 0 to 5 m/km2 ) in the Left Bank river basins of the Volga River. The spatial distribution of the gully heads density (the average value is 0.2 number of gully heads/km2 , the maximum is 5.2 number of gully heads/km2 ) corresponds to the distribution of the gully length density. The connection is determined between the indicators of the gully density and the average steepness of the slopes in the river basins by the method of correlation analysis. The peculiarity of the erosion network of the Saratov region are narrow and long gullies in Cretaceous sediments, having slopes without vegetation, but being in a “preserved” state without signs of active growth. The direct connection between the pasture area and the gully density is fixed due to the wide areas between gullies occupied by the grass land. Areas with extremely high erosion and the development of “badlands” have been identified in the Saratov region. They are located within the Volga upland and are developed on Cretaceous deposits with high slope steepness and low forest cover.
Urbanisation processes affect all components of the natural environment, often causing ecological tensions, leading to negative consequences for humans and their economic activities. Upper Angara region is an old-developed which experienced an upsurge of urbanization after the construction of the Angara HPP cascade HPP cascade on the Angara River in the period of 1950-1980. In this context it is important to have an idea of the structure and dynamics of the natural complexes and population of the territory against the background of urbanization processes. The article is devoted to the complex analysis of the relief and population dynamics in the key area of the downstream bank of the Angara river in Irkutsk. The main attention is paid to the time interval from the beginning of the Irkutsk hydro power station construction till now (1950-2022). Based on the comparison of multi-temporal aerial photographs (AFS), satellite images and topographic maps, the dynamics of morphology, changes in the structure of exogenous processes. Certain quantitative indicators (change in the area of relief elements, volumes of the displaced soil) allowed to estimate high adaptive properties and stability of the geomorphosystem. Five stages of the formation of the urban area, reflecting the development of the space of the study area. The dependence of the population density distribution on morphotypes of building-up of the territory, determining a degree of the anthropogenic loading and geomorphologic risks. It is determined that the maximum anthropogenic impact has shifted from the floodplain-channel complex to the terrace complex since construction of the HPP. Results of researches, can be applied at large-scale zoning on a degree of anthropogenic impact of territories.
The research highlighted the role of small city parks (pocket parks, squares) in promoting the resilience of cities in the Arctic region of Russia. The model cities were Murmansk, Kirovsk, and Vorkuta situated in the European North of Russia. Their modern ecological and geographical characteristics are different, but their green infrastructure has many common features typical to the majority of Arctic cities. Special attention was given to specific regional ecosystem functions of green infrastructure, which are different from more southern regions. Studies of these functions are needed to develop nature-based solutions for providing urban population well-being and biodiversity support, effective management of urban green infrastructure, and ensuring the resilience of social-ecological systems. This is proven by the existing practice which is still limited geographically and mainly concerns large parks. The goal of this research was to demonstrate specific regional ecosystem functions of small city parks, which are different from the ones of large parks in this region. Small urban parks nowadays are mainly regarded as recreational territories, even though they can contribute to creating an important balance between social and natural systems and support the social branch of urban resilience in uncomfortable living conditions. Their ecosystem services differ from those in more southern latitudes. Information ecosystems services (chromatic, aesthetic) are particularly important. They provide a platform for developing social cohesion and creating a sense of place, which allows to withstand negative social processes typical for many cities in the Russian Arctic. Further studies are needed for spiritual ecosystem services as well as for possible ways of monetary assessment of information/cultural ecosystem services. Green infrastructure management of small city parks in the Arctic region requires special attention from municipal authorities.
The aesthetic properties of landscapes are traditionally determined on the basis of a system of visual indicators in the course of field surveys along individual routes. The possibility of using remote methods in such studies depends on the agreement of their results with field data. The article compares the results of the aesthetic assessment of the landscapes of the museum-reserve “Kulikovo pole” based on traditional field methods and high-resolution images obtained from unmanned aerial vehicles (UAVs). The study was carried out in May 2021 for the museum’s ecological trail, about 6 km long, on which observation points with panoramic views are marked, typical for the landscape of hilly-ridged structural-denudation plains. Using the example of three indicators–depth and variety of perspectives, forest coverage and abundance of open spaces in the landscape—it is demonstrated that the method of aesthetic assessment of landscapes based on the combined data of DTM (2 m resolution) and SRTM DEM (30 m resolution) allows you to determine these visual indicators with good match with field results. In some cases, it is required to use corrections because of visual distortion associated with the remoteness of the observed objects. It is shown that the method of aesthetic assessment of landscapes using GIS technologies, which was previously carried out for mountainous areas, can be used for less expressive relief and anthropogenically transformed flat landscapes.
In the geography of tourism, a direction of research on the study of the dynamics and direction of tourist flows is currently rapidly developing, which is based on official statistics at the level of states, regions and lower administrative units. In 2022, Rosstat for the first time pro vided statistics on arrivals and overnight stays in the municipalities of the country, which allowed the authors of the article to classify them according to these indicators for 2021 in the Northwestern Federal District. The classification of municipalities was based on six indicators characterizing the volume of the tourist flow and the degree of development of the hotel and restaurant infrastructure. Due to the COVID-19 pandemic, the Northwestern Federal District experienced a significant reduction in tourist flow in 2020. However, against the backdrop of a seven-fold decrease in inbound tourist flow, domestic tourist flow decreased only by a quarter. At the same time, already in 2021, the federal district saw an almost 1.5-fold increase in domestic tourist flow, which allowed it to replace the decrease in inbound tourist flow in the first year of the pandemic by more than a third. The cartographic analysis accompanying the development of the classification of municipal districts made it possible to see intra-regional differences in the size of the tourist flow and the development of tourist infrastructure, which are not traced when analyzing tourism statistics at the regional level. Thus, in the course of the study, a number of tourist anomalies within the regions were identified, when the volume of the tourist flow does not correspond to the degree of development of the existing hotel and restaurant infrastructure. The results of the study can be used in planning the development of tourism.
The conditions and reasons for the cut-off meanders formation, that create single braided reaches on large rivers with meandering channel, are considered. They appear when developed and steep bends, which have reached critical ratios of parameters in the process of their evolution (l/L > 1.4–1.7; l is the length, L is the step of the bend), are straightened. Cut-off bends are characteristic of rivers, where floodplains are flooded deeply and for a long time during high-water period. In this case, most often, the runoff is redistributed into the new straightening channel branch, although the old channel continues functioning. However, in many cases, in cut-off bends a larger part of water runoff remains in the old channel. This happens if the new straightening channel branch is located behind the reach of the bedrock bank, which exerts a directing (toward the old channel) effect on the flow; the new channel meanders and remains shallow. If the effective water discharge passes within floodplain edges, cut-off bends are formed during extremely high floods. At the same time, they exist for 10–20 years, while the old channel (the old bend) is filled with sediments and dies off, turning into a floodplain oxbow lake. The short-term existence of braided reaches (for a number of years) before the death of the old channel is possible when the loop-shaped bends are straightened due to the oncoming erosion of the banks. In any case, the development of cut off bends is favored by the discharge of clarified waters from the floodplain into the old channel. The presence of cut-off bends, i.e., forms of braided channel, is a factor in the dispersal of runoff along channel branches, which has a significant impact on their channel changes, development of bends and conditions for channel processes management while water management of rivers as a whole.
In this paper, we assessed soil erosion within the largest river basins of the Russian Federation (Ob, Yenisei, Lena, Yana, Indigirka, Kolyma). Soil losses have been estimated with RUSLE based on the digital elevation model of the maximum available resolution (≈90 × 90 m). The results are compared with existing global estimates and previous studies for the Russian territory. The conclusion was made about high uncertainty of small-scale erosion estimates made on a subcontinental scale, which is explained by the high sensitivity of RUSLE to the parameterization of the length and steepness of slopes. In the sublatitudinal direction, for all basins there is an increase in erosion from north to south, corresponding to the general strengthening of agricultural land use. Based on comparison with the suspended sediment yield, the conclusion was made about an exceptionally accumulative regime of the considered watersheds: more than 90% of sediments do not reach the estuaries of the rivers.
The article presents a quantitative analysis of differences in the calculation of the LS-factor arising from the use of various options for the global digital elevation model GMTED2010: “Mean”; “Breakline emphasys”; “Median”. The global digital elevation model SRTM (C-SIR radar) was used as a reference for comparative analysis. In addition, an assessment of differences between values of LS-factor obtained by various methods was made. In this case, 4 methods for calculating the LS-factor were used, proposed in the: USLE method; RUSLE method; methodology proposed by the Research Laboratory of Soil Erosion and Channel Processes of Moscow State University, methodology published by Moore I.D. and Nieber J.L. in 1989. The analysis was carried out within 4 test areas reflecting the main types of relief in the south of the European territory of Russia. It has been established that the closest results in the calculation of the LS-factor to the SRTM C-SIR model are given by the variant of the model GMTED2010 “MEAN”. The errors arising between the SRTM C-SIR and GMTED2010 “MEAN” models within moderately dissected plains are 7–54%, where most of the arable land is located. At the same time, errors within mountainous areas or stratal-accumulative plains and lowlands are 68–322%. An analysis of the use of various formulas for calculating the LS-factor shows that within all test areas the lowest values are obtained using the methodology proposed by the Research Laboratory of Soil Erosion and Channel Processes of Moscow State University. and the highest values using USLE, or using the methodology proposed by Moore I.D. and Nieber J.L.
