This paper explores the potentialities of discriminant analysis for the identification of abandoned agricultural lands using their reflectance spectrum properties. A method of automated detection of fallow lands is proposed. Using experimental data received from the agricultural lands of the Belgorod Region, we propose equations that allow an agrarian land to be classified as an arable or fallow land in an automated mode. The accuracy of fallow land recognition is 71%. It is found that seasonal normalized difference vegetation index (NDVI) values computed from MODIS data in the period of late September - early October are most informative in terms of abandoned agricultural land identification. It is shown that the use of the minimal NDVI values is much more efficient for the identification of fallow land when compared with the mean NDVI values.

Пространственно-временная изменчивость биоклиматического потенциала Центрального Черноземья

An active process of the invasion of woody vegetation, resulting in the formation of light forests, has been observed in predominantly herbaceous small dry valleys of the forest-steppe uplands of the East European Plain over the past two decades. This paper investigates the spatial features of the density of trees in such light forests and its relationship with relief parameters. The Belgorod Region, one of the administrative regions of European Russia, was chosen as a reference for the forest-steppe zone of the plain. The correlation between some relief characteristics (the height, slope, slope exposure cosine, topographic position index, morphometric protection index, terrain ruggedness index, and width and depth of small dry valleys) and the density of light-forest trees was estimated. The assessment was carried out at the local, subregional and regional levels of generalization. The relief influence on the density of trees in the small dry valley network is manifested both through the differentiation of moisture within the territory under study and the formation of various conditions for fixing tree seedlings in the soil. This influence on subregional and regional trends in the density is greater than on local trends. The results obtained are important for the management of herbaceous small-dry-valley ecosystems within the forest-steppe uplands in Eastern Europe.

This article showcases the outcomes of a comprehensive spatiotemporal dynamic analysis conducted in forest vegetation areas within the forest-steppe zone of the Central Russian Upland (eastern Europe), spanning the period from 1970 to 2020. This study utilized high-resolution data from the Corona satellite system from the year 1970 as well as satellite imagery from the ArcGIS World Imagery database. Soil properties and their changes were assessed based on the analysis of soil bulk density (930 samples), soil organic carbon features, pH, available phosphorus, and the composition of salt extracts (1362 samples). We collected and analyzed 3920 soil samples in the field to study the impact of shelterbelts on soil moisture over a period of two years. For six selected key sites with a total area of 1722 km², it was found that over a 50-year period, the area covered by forest vegetation increased from 14% to 24%. This expansion was primarily due to the planting and growth of young shelterbelts in the 1970s–1980s as well as widening anti-erosion shelterbelts on slopes and gullies. The average linear growth rate of forest vegetation boundaries was found to be 23.5 m (4.7 m per decade) for the entire study area. The expansion was highest on west-facing slopes, which was attributed to the higher moisture content from windward atmospheric precipitation events. However, alongside the increase in forest cover, degradation was also observed, particularly in old-age shelterbelts, which was attributed to increased fragmentation and mortality. A gradual increase in the extent of shelterbelt degradation was observed from the northwest to the southeast within the forest-steppe region, corresponding to areas with a drier climate. Additionally, the impact of shelterbelts on soil properties and soil cover was analyzed using four key sites and using fields and laboratory research methods. We detected a lateral uptake of substances from plowed soils into the soils of shelterbelts and vertical uptake from deep layers. The two-year observations (2020 and 2021) of soil moisture during the growing season (May–September) in two climatically contrasting forest-steppe areas revealed a more intensive accumulation of soil moisture in fields west of shelterbelts compared to those to the east of them, particularly within the 10 m zone near the shelterbelts. This can be attributed to arable fields on the windward side receiving more moisture compared to the leeward side. The formation of striped microstructures in the soil cover that occurred under the shelterbelts and on adjacent arable lands was influenced by various factors such as microclimatic conditions, vegetation types, ecological conditions for soil fauna, and human-induced soil processing and transformation along the shelterbelt boundaries. Shelterbelts and their adjacent areas in agro-landscapes are considered to be self-developing natural–anthropogenic geosystems with their own organizational structure. Therefore, their study is recommended as an integral part of modern geographical zoning.

Afforestation trends were compared between two continentally-distinct, yet similar ecoregions to characterize similarities or differences in forest advancement due to natural and anthropogenic forcings. Temporal changes in forest cover were analyzed using high resolution aerial and satellite photographs for Southeast Iowa, USA, and satellite photographs for the western Belgorod Oblast, Russia. An increase in forested area was shown to occur over a 44-year period from 1970–2014 in Iowa where afforestation was reflected by the aggregation of smaller forest units. In the Belgorod region the opposite occurred in that there was an increase in the number of smaller forested units. The rate of forest expansion into open grassland areas, previously used as haying lands and pastures, was 14 m decade⁻¹ and 8 m decade⁻¹ in Iowa and the Belgorod Oblast, respectively. Based on current trends, predicted times for complete forest coverage in the study areas was estimated to be 80 years in Iowa and 300 years in the Belgorod Oblast. In both the Iowa and Belgorod Oblast, there was an increase in annual precipitation at the end of the 20th and the beginning of the 21st centuries, thus providing a contributing mechanism to forest advancement in the study regions and implications for future management practices.