PATTERNS OF LONG-TERM DYNAMICS OF LOCAL GEOSYSTEMS IN THE SOUTH-EAST OF BELARUS
The purpose of the work is to study the patterns of long-term (tens-hundreds of years) anthropogenic changes in geosystems on the example of the south-east of Belarus (Gomel region, Belarussian Polesie). Research objectives: study of changes in the structure of land use and related anthropogenic; study of the long-term dynamics of the structure of natural- anthropogenic landscapes; geobotanical surveys on test sites; study of the influence of the history of land use on the current state of the vegetation cover. The studies were carried out on 5 test plots representing different natural and landscape conditions (area of test plots from 52.2 to 73.7 km2). Time range of research: from the middle of the 19th to the beginning of the 21st century. The land use structure was reconstructed on 4 time slices and compared with the current one. Natural-anthropogenic landscapes were classified based on the ratio of land types.It has been established that changes in the structure of land use in the studied areas are associated with the peculiarities of economic development in certain landscape conditions (soil fertility, waterlogging). Based on the structure of land use, the territory of the studied sites at each time slice was assigned to the corresponding class and subclass of natural- anthropogenic landscapes. Long-term dynamics at the level of classes and subclasses of natural-anthropogenic landscapes was studied at each site.There is spatio-temporal variability in changes in land use types. Within the same area during the period under consideration there was a repeated change of classes and subclasses of natural-anthropogenic landscapes. The direction of these changes in classes and subclasses of natural-anthropogenic landscapes does not coincide in different areas.It has been established that the influence of previous land use is reflected in the indicators of the plant component of forest and non-forest geosystems. Vegetation cover of long- existing anthropogenic geosystems is distinguished by a higher proportion of synanthropic (1,7 times) and alien species (1,8-2,5 times) species. Forest geosystems formed on the site of former arable, meadow and other non-forest lands are characterized by a reduced proportion of forest species and an increased proportion of synanthropic and alien species in the flora.Alien species are a sensitive indicator of the previous history of forest geosystems. Alien plant species ( Acer negundo L., Robinia pseudoacacia L., Impatiens parviflora DC., Solidago canadensis L., Parthenocissus quinquefolia (L.) Planch.) are often found in forests formed on former agricultural lands. In addition, forests on the site of former agricultural lands are characterized by an increased degree of damage to the forest stand by pests.