Quasi­homogeneous periods in the temperature variation of the Northern and Southern hemispheres, as well as the Globe were identified based on the analysis of linear trends in normalized mean monthly air temperatures. Differences in the annual variation of the linear trend coefficients for the Northern and Southern Hemispheres were found. The revealed features are not consistent with the existing ideas about the greater severity of modern warming in the winter season. Possible reasons for the differences are related to the general atmosphere and ocean circulation. The intertropical convergence zone is considered as a factor in the detected differences in linear temperature trends in different periods of the year.

   The results of the statistical assessment of the influence of the changing weather­climatic conditions of the territory of Belarus on the productivity of potatoes in order to build a settlement model of yields are presented. The study was completed from 1960 to 2019. Calculations are made relative to the climatic component as a predictor, taking into account the deviations of the air temperature and atmospheric precipitation from the long­term climate norms of the months that have the most significant impact on the yield of culture. The adequate model of variability of the yield of potatoes, cultivated in Belarus, is constructed. The research results are relevant for solving forecasting problems.

   Information on anthropogenic air pollution with sulfur dioxide in Belarus and on its influence on the formation of the observed concentration of ground­level ozone is presented. The problem was solved by constructing a regression equation approximating the dependence of the ground­level ozone concentration on meteorological conditions and ozone precursors. The presence of sulfur dioxide in urban air leads to a decrease in the concentration of ground­level ozone due to the binding of nitrogen dioxide. It is the photolysis of the latter that is the source of atomic oxygen and the subsequent generation of ozone. A feature of the regression equation is investigated when taking into account a factor that negatively affects ground­level ozone sometimes leads to an increase in its calculated concentrations.

   The article presents long­term changes in the flow rates of the rivers of the Orsha Artesian basin, it is shown that the main factors influencing the conditions of flow formation are primarily climatic, geomorphological and hydrological­hydrogeological conditions of the region. On the territory of the Orsha Artesian basin, a statistically significant decrease in runoff during the spring flood and a decrease in its share in the annual runoff were revealed (the power of the negative trend ranged from 5.4 to 22.0 %). A significant increase in the share of winter runoff in the annual distribution for the rivers of the Orsha Artesian basin was revealed. As a result of constructing two­factor regression models of the relationship between winter expenditures and spring flood water expenditures, it was found that an increase in the share of winter river runoff is associated with an increase in the air temperature of the cold months, with an increase in the frequency of thaws, and the passage of winter floods. The results obtained indicate that the underground runoff in the winter has increased, due to mild winters, the presence of frequent thaws and sufficient humidification of the territory .

   This work presents the results of a tourist and recreational assessment of the natural potential of 26 rivers of the Grodno and 15 rivers of the Brest region of Belarus, and on the basis of which the spatial and functional tourist and recreational zoning of their water areas was carried out with the allocation of 54 and 41 sections of rivers respectively, differing in the structure of subtypes of the main types of their tourist­recreational use in the field of water tourism. Comparative analysis of the share of river sections suitable for their tourist­recreational use in the studied regions revealed a general tendency for their share to increase in the direction from type 1 to type 3, which is replaced by a diametrically opposite one when passing from type 3 to type 4. In addition, the article describes the differences in the structure of 15 and 12 subtypes within 4 the identified types for river sections for Grodno and Brest regions respectively. The practical results of assessing the natural tourist and recreational potential of rivers, based on their functional zoning and typing according to the main types of tourist and recreational use in the western and southwestern regions of Belarus, can be used for measurements development to improve the efficiency of the use of sites in order to develop river tourism.

   One of the largest water users of the republic are organizations of water supply and sewerage services and housing and communal services that discharge urban wastewater after treatment at sewage treatment plants of settlements into surface water bodies. The quality of wastewater discharged into surface water bodies from wastewater treatment plants of settlements is significantly influenced by the qualitative characteristics of wastewater entering the treatment, the wastewater treatment technologies used and the efficiency of wastewater treatment plants. The development of a system for rationing wastewater discharged through the sewerage network to wastewater treatment plants in settlements will reduce the load on wastewater treatment plants, and, as a result, reduce the likelihood of dumping insufficiently treated wastewater into surface water bodies.

   The article deals with the results of comparative study of the influence of mineral (Basacote Plus 6M) and organic (Ekogum complex, MaKloR (in 5 and 10 % concentrations)) fertilizers on the biometric and bioproductive characteristics of the generative organs of five­year­old plants of early­ripening (Ben Lear) and late-ripening (Stevens) varieties of large­fruited cran-berry in experimental culture on recultivated areas of peat deposits in Smolevichi (Minsk region) and Dokshytsy (Vitebsk region) districts in contrasting weather conditions in the seasons of 2019 and 2020. Significant interregional, genotypic and inter­variant differences in the response of experimental plants to the tested agricultural practices were revealed. In the first year of research (characterized by an increased temperature background and a high level of precipitation), the stimulating effect of fertilizers on the morphometric and production characteristics of cranberry fruits was revealed (most pronounced in the early­maturing variety). The moderately cool and rainy weather of the vegetative season in 2020 contributed to a significant weakening of the influence of the tested agricultural technics on the studied characteristics of cranberry fruits: there was a decrease in the increase in fruit yield compared to previous season (from 3 to 18 times). It is shown that in a two­year cycle of observations in the Smolevichi district, all the tested agricultural technics contributed to an increase in its size with the greatest, and similar in both varieties, the effectiveness applying of Basacote Plus 6M and Ekogum complex. In the Dokshytsy district, along with the mineral one, the most effective was the use of MaKloR (5 % ), which was 1.5 times inferior to it in this regard, in the absence of an impact on the productivity of the late­maturing variety of the Ekogum complex and MaKloR (10 %).

   The article considers the issues of the regional geographical analysis of bryofloristic complexes of the Belarus. The studies were made in Belarus and Eastern Europe on the basis of mapping on 390 squares (100 × 100 km). Four subregions (boreal­-Baltic, boreal-­taiga, nemoral-­western and nemoral-­central) are distinguished in the Belarus, the distribution of species of bryophytes was characterized, results of the geographic analysis for each subregion were presented. Studies have shown that the geographical structures of the bryofloristic complexes of Belarus show, on the one hand, their close relationship with the respective bryofloras of the subregions, and on the other hand, a pronounced specificity among themselves, especially those related to different natural regions. Closer ties with the main parts of the subregions show the territories of the nemoral zone, in a smaller one ­ the boreal zone. In general, it can be concluded that on the territory of Belarus bryophytes do not form a single bryoflora, but are represented by 4 interacting fragments of larger bryofloras of the regions (boreal and nemoral) and subregions (boreal-Baltic, boreal­-taiga, nemoral­-western and nemoral-­central).

   The aim of the study was species identification of nematodes from the family Protostrongylidae parasitizing on red deer from enclosures of the Vileiskaya, Zhlobin, Lyubanskaya Svetlogovskaya and Kalinkovichi regional organizational structures. From the material collected in 2019, morphometric characteristics of larvae were used for species identification. As a result, we
identified nematodes belonging to Elaphostrongylus cervi Cameron, 1931. The species parasitize in the brain and intermuscular connective tissue of red deer, causing the disease elaphostrongylosis, known as one of the most pathogenic for ungulates.

   In this study the hypothesis about the purine nucleoside inosine's positive effect on the plant objects germination was checked. In the course of the work, the effect of inosine solutions in samples of 0,05-0,3 % on biometric indicators of oni­ on seeds of the Stuttgarter Riesen variety germination was evaluated. The best indicators were found in groups germinated in 0,1 and 0,15 % solutions of inosine.

   The place of growth of Sempervivum ruthenicum (W. D. J. Koch) Schnittsp et C. B. Lehm. has been established between Verkhnie Zhary and Gden villages in the Bragin district of the Gomel region. This is a representative of the steppe floral complex, which has a high conservation status and a fairly narrow distribution area on the territory of Belarus, limited to the extreme south­east of the country. Due to the location of the species in the zone of intense anthropogenic impact (near the highway), prerequisites are created for violating the integrity of the ecotope and, as a result, the need to take protective measures. A brief description, information about the modern distribution and ecological and biological features of this species is given.

   An effective method of purification of sodium chloride solutions from organic and inorganic impurities is proposed, which can be used in methods of purification of secondary products of mineral enrichment. In the system, when the precipitator is introduced, a solid inorganic phase is formed, which sorbs the amino­containing organic impurities, flocculates and is precipitated by a polymer (anionic polyelectrolyte). When using the developed method, the degree of purification of sodium chloride solutions from inorganic and organic impurities is not less than 99.5 %.

   The management of wastewater, that is generated in the course of production activities of enterprises and discharged into the environment, including through the sewage systems of settlements, is an important environmental task. The choice and justification for the use of wastewater treatment technology should be carried out by the enterprise based on a set of environmental and economic indicators, taking into account the industry-specific characteristics of production. The scientific­practical approaches presented in the article make it possible to choose the most optimal ways to prevent the formation of wastewater and wastewater treatment technologies from the totality of technical, environmental and economic aspects of the enterprise.