In-field variation of environmental conditions, including driven by positional factors leads to fluctuations in agricultural production costs. We investigated the dependence of intra-field Normalized Difference Vegetation Index (NDVI) variation—an indicator of green phytomass—on the area and condition of adjacent forest belts and erosional landforms. A total of 39 Landsat satellite images were used to calculate Spearman correlation coefficients to link the NDVI with neighborhood indicators. These indicators included the area of forest shelterbelts and erosional landforms within a 150 m radius. Seasonal correlations and their variation depending on hydrothermal conditions were revealed. The positive impact of forest belts on the green phytomass is observed at a distance of 90–150 m. Erosional dissection affects intra-field soil variation in spring and early summer. In the summer, proximity to living forests was a critical factor. In spring, waterlogged ravines and delayed snowmelt near forest belts restrained phytomass development in field areas. From May onward, proximity to or position within erosional forms favored phytomass growth. The strength of the influence of adjacent forest plantations on the phytomass of agricultural fields depended on the total hydrothermal effect over a period of about two months. NDVI shows increased dependence on forest belts during hot and dry periods, and on erosional landforms during wet and cold periods.
The article examines the climatic prerequisites of the formation of arid conditions and desertification processes in the Nakhchivan Autonomous Republic. Key climatic characteristics, determining the aridization intensity and spatial differentiation of arid conditions, have been identified based on a comprehensive interdisciplinary approach, including climatic, geographical, geomorphological, and cartographic analyses. It has been revealed that specific features of the aridity manifestation largely depend on landscape features of the area. A map of desertification has been compiled on the basis of climatic and geomorphological data. It is shown that rational use of natural resources may stabilize the ecological status of arid geosystems and slow down desertification despite extreme climatic conditions. The results obtained are of practical importance for environmental monitoring, territorial planning, and development of adaptive land use schemes under conditions of climate change.
This article presents the results of observations of vegetation dynamics along the transect located in the middle part of the Volga–Akhtuba floodplain. The transect was established in 1954 by the Caspian Expedition of the Geography Department of Moscow State University. Its total length is 14.7 km. Ninety-six sample plots were located along the transect, at which phytosociological relevés were made. These plots were resurveyed in 1982 and 2025. Using cluster analysis, five groups of plant communities were identified. A comparison of the representation of these groups along the transect revealed that aquatic, marsh, and meadow phytocenoses remain in the middle part of the Volga–Akhtuba floodplain. However, from 1954 to 1982 and again to 2025, processes of xerophytization and ruderalization of the vegetation cover have occurred. Thus, there were five sites where plant communities of meadow-steppe wetlands were found in 1954, nine in 1982, and 22 in 2025. The main cause of vegetation xerophytization is the reduction in flood volumes under regulated water flow conditions.
A method for assessing land degradation in the desert zone of Kalmykia has been developed, combining radar and multispectral remote sensing data. The basis is the assessment of the projective cover of vegetation and the change in nanorelief using the interferometric coherence method, supplemented by spectral indices (SAVI, LAI, shortwave albedo). The resulting feature space allows us to classify a section of territory into one of five possible types of objects: salt marshes, open sands, and weakly, moderately, or densely overgrown sands. The classification accuracy of the trained neural network was confirmed by field data with a correspondence of 70 to 100
To assess the ecological position of the pasture vegetation of Karakalpak Ustyurt, belonging to the middle and southern subzonal types of Turanian deserts and represented by the perennial saltwort ecological–physiognomic type of vegetation (Botanicheskaya geografiya…, 2003), an ecological analysis of geobotanical descriptions collected in various years, 1953–1973 and 2017–2021, was carried out. The data array analyzed represents various types of pastures: biyurgun (Anabaseta salsae), wormwood (Artemisieta terrae-albae), hawthorn (Xylosalsoleta arbusculae), black saxaul (Haloxyleta ammodendron), keireukove (Caroxyleta orientale), potash (Kalidieta caspicum), and sarsazan (Halocnemeta strobilacei). They are common on gray–brown zonal saline, sandy, gypsum, takyr, and solonchak soils. According to the moisture scale developed by I.A. Tsatsenkin (1967), communities occupy a segment from 10 to 58 steps, which corresponds to desert and dry meadow moisture. On the soil richness–salinity scale, the values vary from 17 to 20 steps, reflecting predominantly the moderately saline level of salinity. The CCA-ordination of geobotanical descriptions allowed us to consider the differentiation of vegetation in the space of three ecological factors: W, soil moisture; S, soil salinity; D, degree of anthropogenic degradation. For the central group of descriptions, an in-depth analysis of the species composition was carried out, followed by ordination, the results of which are presented in the form of a cluster dendrogram. The analysis showed that the greatest scatter of data is observed for the salinity factor (S), which indicates its leading role in structuring vegetation. The central group is represented by background pasture communities.
