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The advantages of a quantitative assessment of the spatial and temporal variability of the boundaries and volumes of ravines using modern means and methods of aerial photography from an unmanned aerial vehicle (UAV) are substantiated, in contrast to traditional survey methods (linear method of benchmarks, tacheometric, aerial and space photography, laser scanning). The erosion zoning and mapping of linear and gully formations on the territory of the Kuitunka, Tarbagataika, and Kunaleika river basins (Selenga middle mountains) are carried out. The reanalysis data were used to assess extreme meteorological events leading to the acceleration of erosion processes. Paleontological material confirms the long duration of erosive-accumulative processes in the Nizhnyaya Bulanka depression. High-accuracy multi-temporal orthophotomaps and digital elevation models of Bulanka gully using unmanned aerial vehicles were produced. The method of quantitative estimation of gully formation rates is offered, which allows estimating with high accuracy the change of area and volume characteristics of erosive forms.

The reactions of 3-and 4-nitrophthalimides with hydroxylamine in aqueous alcohol media were studied. A mixture of 3-amino-4-nitro-and 4-amino-5-nitrophthalimides is formed in the case of 4-nitrosubstituted derivative, whereas 3,6-dihydroxyphthalimide is unexpectedly found to be the main product of the reaction of 4-rfitrosubstituted derivative. A possible mechanism of the transformation was suggested.

Desertification is one of the most complex environmental problems in the Central Asian region. In addition to climatic factors affecting land degradation, in the border territories of Russia and Mongolia the intensification of desertification processes is influenced by human activities. A cartographic analysis of meteorological parameters, as well as vegetation state and dynamics spatial distribution based on the NDVI, was carried out. Dry zones occupy 65% of the area of Russia-Mongolia border territories. The prevailing climate zone is a semi-arid. The features of the dynamics of vegetation in the wet (1982-1999) and drought (2000-2015) periods are revealed. In the period from 1982 to 2015 a positive trend of NDVI is observed for 78% of the border areas and negative is for 22%. During the wet period the area of negative trends for both Russia and Mongolia amount 1.5% of the territory, primarily due to deforestation. The drought period is characterized by a nearly twentyfold increase in the areas of negative NDVI trends for the whole border territory. The analysis of the correlation of meteorological parameters and vegetation revealed that in drylands with negative NDVI trend, climate-induced desertification covers 63%, and anthropogenic 37% of the total area affected by desertification.

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The article discusses the experience of compiling large-scale vegetation maps, the advantages of using aerial photography data from a radio-controlled unmanned aerial vehicle (UAV) and the technology of geo-information systems in combination with ground-based traditional geobotanical mapping methods. The use of remote sensing data is one of the ways to quickly obtain data for vegetation mapping. Currently this method is actively used and developed. However, satellite data has several disadvantages. The use of UAV is a promising direction for timely and cost-effective environmental monitoring. Using the aerial photo obtained in this way, it is possible, on the one hand, to trace the dynamics of vegetation during one season, and on the other, to identify and map both different plant communities and populations of individual species that do not coincide in the phenological phase of development with each other. The aim of the study was to reflect the heterogeneity of vegetation cover on a detailed geobotanical map in a simple way, which will act as the basis for further research. The map constructed by the described method is the most objective reflection of the state of the vegetation cover.

For the first time, the syntaxonomic diversity of steppe vegetation along the Baikal-Gobi transect was determined, represented by 49 associations belonging to 23 formations, 5 florocoenotypes, and 3 ecological-historical series. The classification construction according to the ecological-phytocoenotic dominant-determinant principle was based on data collected during field research and processed using traditional geobotanical methods: route reconnaissance studies, geobotanical descriptions, cluster and gradient analysis. Units of this approach give an idea of the current state of communities at a certain stage of succession, and syntaxa reflect the ecological features of vegetation inherent in the territory. This approach has an applied value, expressed, in particular, in mapping – the volume of the main syntaxa is smaller compared to the ecological-floristic approach, which makes it possible for a more meaningful analysis in large-scale mapping.