Database of the results of radioecological monitoring of contaminated agricultural lands of the Tula NIISH

For the radioactively contaminated territory of the Tula Research Institute of Agriculture, a database has been created for storing spatially oriented information. The created database contains information about the location of agricultural areas; crop rotation structure; distribution of values of specific activity of 137Cs on agricultural lands; agrochemical indicators of soils of agricultural territories (content of humus, potassium, phosphorus, acidity); soil types; relief. It also contains a calculation module for assessing the content of 137Cs in crop and livestock products. The accumulated data array will be used for designing adaptive landscape farming systems using information on the 137Cs content in the soil generalized over a long-term period.

Long-term dynamics of radionuclide contamination formation in the industrial іchthyofauna of the Kaniv Reservoir

The aim the study is to determine the temporal parameters of the long-lived radionuclides specific activity decrease in the commercial fish species of the Kaniv Reservoir for the period 1987–2021. Rutilus rutilus, Scardinius erythrophthalmus, Blissa bjoerkna, Abramis brama, Pelecus cultratus (peaceful species) and Esox lucius, Stizostedion lucioperca (carnivorous species) were selected in the middle and lower parts of the reservoir in January 2021 to determine the current levels of radioactive contamination in the representatives of the commercial ichthyofauna of the Kaniv Reservoir. The specific activity of 90Sr and 137Cs was determined in the entire body of fish by conventional radiochemical and gamma-spectrometric methods. The analysis of the dynamic characteristics of the radionuclides content in the representatives of the reservoir ichthyofauna was carried out on the basis of the results of studies of 90Sr and 137Cs content in fish during 1987–2012 and their specific activity in the body in 2021. In 2021, the average specific activity of 90Sr in fish was 0.6–1.6 Bq/kg, 137Cs - 2.4–13.2 Bq/kg. According to the results of previous studies, the average specific content of 90Sr in the fish of the Kaniv Reservoir decreased by approximately 6.5 times - from 60 ± 30 to 9 ± 3 Bq / kg during 1987-1993, and by 2003 it decreased by another 5 times up to 1.8 ± 0.8 Bq / kg and did not exceed the values recorded in freshwater fish in Ukraine before the Chernobyl accident in 1979–1985. Consequently, during the period of 2003–2021 the levels of 90Sr content in fish from the Kaniv Reservoir remained virtually unchanged. Based on the data on 137Cs accumulation in various feeding types fish in the Kaniv Reservoir, time parameters describing a decrease in the element specific activity were determined. During 1987–2021 the rate of decrease in 137Cs content in peaceful and predatory fish did not differ significantly and amounted to 0.10 ± 0.01 year-1, the period of effective half-decrease was 6.7 ± 0.7 years. Analysis of long-term data made it possible to distinguish 2 periods during which the specific activity of 137Cs in the fish organism decreased at different rates. In 1987-2004, 137Cs content levels in peaceful fish decreased from 70 ± 22 to 6.1 ± 2.2 Bq/kg, in carnivorous species - from 202 ± 41 to 19.8 ± 7.6 B/ kg, i.e. approximately by 10–11 times, which corresponds to a half-decrease of about 6 years. In 2004–2021 the element content in peaceful fish decreased to 2.9 ± 0.7 Bq/kg, in predatory fish - to 7.3 ± 4.1 Bq/kg, that is, by another 2–3 times, which corresponds to a half-decrease of 12 ± 3 years. Thus, it was found that the rate of decrease in 137Cs specific activity in fish slows down over time. The obtained parameters will make it possible to predict with a high degree of accuracy the dynamics of the radionuclide contamination formation in ichthyofauna in the event of artificial radionuclides entering aquatic ecosystems as a result of emergency situations. Key words: Kaniv Reservoir, fish, radionuclides, longterm dynamics, rate of decrease.

The regularities of 137Cs accumulation in the aboveand underground parts of aerial-and-aquatic plants originated from various types of reservoirs in the Polissia and the Forest-Steppe of Ukraine

The aim of the study was to establish the regularities of 137Cs accumulation in the above- and underground parts of aerial-and-aquatic plants originated from various types of reservoirs in the Polissia and the Forest-Steppe of Ukraine, located in territories varying in the degrees of radioactive contamination. The studies were carried out in 2014–2018. Higher aquatic plants were sampled in eutrophic, oligotrophic, and dystrophic reservoirs including large and small ones as well as lakes and ponds used for various purposes. The reservoirs were located in the areas that are considered conditionally clean relative to the density of 137Cs contamination, or are classifed as zones of enhanced radiological control, guaranteed voluntary resettlement, unconditional (guaranteed) resettlement and exclusion zones. The objects of research were 8 species of aerial aquatic plants widespread in the fresh water reservoirs of the Polissya and the Forest-Steppe of Ukraine. The specifc content of 137Cs in the aboveground parts, rhizomes, and roots of the plants was determined by common gamma-spectrometric methods. The analysis of the obtained results revealed a common regularity typical of plants from all the studied reservoirs – the levels of 137Cs in the aboveground parts and the rhizomes did not differ signifcantly, but in the ground roots they were signifcantly higher. The specifc activity of 137Cs in ground roots of Phragmites australis exceeded its activity in above ground parts by 6–25 times, in Tupha angustifolia – by 5–20, Glyceria maxima by 7–10, Scirpus lacustris by 4–9, Alisma plantago-aquatica – by 3 times, Sagittaria saggitifolia - by 2, Butomus umbellatus – by 3, Iris pseudacorus - by 4 times. The levels of 137Cs content in aboveground parts and rhizomes in most of the studied plants did not differ signifcantly. The results of the study will further make it possible to assess the role of aerial-and-aquatic plants in the bottom sediments radioactive contamination and to improve the understanding of the role of higher aquatic plants in the processes of radioactive elements migration and redistribution in aquatic ecosystems. The revealed regularities of 137Cs levels formation in the underground parts of plants should be taken into account in determining the radiation dose of plants growing in radionuclides contaminated reservoirs. Key words: aerial-and-aquatic plants, aboveground parts, underground parts, roots, rhizomes, 137Cs, reservoirs, lakes, ponds.

Yield and quality of carrots when using the Gumiton organo-mineral complex in conditions of radioactive contamination

The aim of this work is to assess the impact of Gumiton peat-based organo-mineral complex on the productivity and quality of carrots and the transition of 137Cs from soil to root crops under conditions of radioactive contamination. According to the results of field experiments on gray forest and soddy-podzolic soils of the Kaluga region of Russia, it is shown that leaf treatment with Gumiton of carrot plantings in different phases of crop development increases the yield of root crops by 20-40%, depending on the variety, soil type and agricultural background. Analysis of studies in the growing experiment on soddy-podzolic soil showed that Gumiton treatment increases the yield of carrots by 30%. The rate of decrease of 137Cs content is 1,2-1,25 times. Gumiton is a highly effective preparation for carrots, which increases the productivity and quality of the crop and helps to reduce the intake of 137Cs in root crops in radioactively contaminated areas.

Yield and quality of carrots when using the Gumiton organo-mineral complex in conditions of radioactive contamination

The aim of this work is to assess the impact of Gumiton peat-based organo-mineral complex on the productivity and quality of carrots and the transition of 137Cs from soil to root crops under conditions of radioactive contamination. According to the results of field experiments on gray forest and soddy-podzolic soils of the Kaluga region of Russia, it is shown that leaf treatment with Gumiton of carrot plantings in different phases of crop development increases the yield of root crops by 20-40%, depending on the variety, soil type and agricultural background. Analysis of studies in the growing experiment on soddy-podzolic soil showed that Gumiton treatment increases the yield of carrots by 30%. The rate of decrease of 137Cs content is 1,2-1,25 times. Gumiton is a highly effective preparation for carrots, which increases the productivity and quality of the crop and helps to reduce the intake of 137Cs in root crops in radioactively contaminated areas.

Possibility of using technogenically polluted floodplain landscapes

The article provides a modern assessment of technogenically polluted floodplain landscapes of various rivers of the Polesian Lowland. The carried out ecological monitoring of productivity, radioactivity of perennial grasses and fertility of floodplain soils revealed the following results, tendencies and regularities: the most favorable set of conditions for obtaining an air-dry mass of grasses with the highest productivity up to 5 t / ha was found on the floodplain of the Iput River, possibly used as hayfields floodplain lands at present, with a 137Cs pollution density below 555 kBq / m2 obtained after the Chernobyl accident, the use of floodplains as hayfields with a 137Cs pollution density above 555 kBq / m2 is impossible, coarse fodder from the floodplains of the Iput and Besed rivers is 6.4 and 6.6 times higher than the permissible level of 137Cs content in products, the content of organic matter, calcium and magnesium grew in the landscape of the floodplain by subsystems: near-river → central → near-terrace landscape, a high content of mobile phosphorus and exchangeable potassium, respectively, from 227 to 362 and 122 to 266 mg / kg were found in the near-terrace subsystem of the studied floodplains, the effect of fertility on an increase in productivity is positive, with the exception of the effect of acidity and negative on an increase in specific activity 137Cs, established an average role (0.30 ˂ r ˂ 0.70) of fertility indicators in increasing productivity, the correlation coefficient (r) ranged from 0.41 to 0.64 and -0.38, revealed a strong role (r ˃ 0.70) of the content of phosphorus available for a plant in a decrease in the specific activity of 137Cs in the air-dry mass of grasses, the correlation coefficient (r) was –0.70.

Radioecological assessment of forage agricultural land in the southwestern areas of the Bryansk region based on a set of statistical models

This paper presents a radioecological assessment of forage agricultural land in the southwestern districts of the Bryansk region based on data characterizing the variability of the radionuclides content in the soil. Concentration of 137Cs in forage was calculated taking into account the proba-bility distributions of 137Cs soil contamination density and the soil to plant transfer factor. The pro-cessing data of the radioecological survey has shown the soil contamination density with 137Cs of agricultural lands in the southwestern areas of the Bryansk region obeys a lognormal law. The authors have used statistical models and software modules for the radioecological assessment of forage lands. Risks of exceeding the 137Cs content standards in forage obtained on soils with different texture have been calculated. The limiting levels of contamination of pastures and hay-fields with 137Cs, ensuring compliance with the specified risks for forage, have been estimated. The lowest limiting soil contamination density is characteristic of organic soils, which can be con-sidered “critical” from the point of view of 137Cs intake into forage. The authors have predicted the time of remediation of forage lands in the southwestern districts of the Bryansk region in the ab-sence of protective measures based on a probabilistic approach. The time period during which the risk of forage contamination for sandy, sandy loam and clay loam soils will decrease to 10% varies for the areas under consideration in a wide range, not exceeding 64 years. It is concluded that it is advisable to substantiate the value of the acceptable risk of forage contamination, taking into account radiological and socio-economic aspects.

ANXIOUSNESS AND QUALITY OF SLEEP IN CHILDREN WHO WERE IN QUARANTINE DURING THE COVID-19 PANDEMIC

Objective: to assess the level of anxiety and characterize the quality of sleep in children living in radioactively contaminated areas in comparison with children who were not affected by the Chornobyl-affected contingents that were quarantined in connection with the COVID-19 pandemic. Materials and methods. The indicators of the level of anxiety were studied using the scale of self-assessment of the level of anxiety Ch.D. Spielberger, sleep quality was assessed using a standardized questionnaire for self-completion of PSQI and 137Cs content was measured in children. The main group consisted of 96 children who were quarantined due to the COVID-19 pandemic and permanently lived in radioactively contaminated areas of Zhytomyr and Rivne regions with a soil contamination density of 137Cs from 18 kBq/m2 to 235 kBq/m2. The age of children ranged from 10 to 17 years. Among them were 33 boys and 63 girls. The comparison group consisted of 52 children of similar age, including 26 boys and 26 girls. These children lived permanently in Kyiv and were not victims of the Chornobyl disaster. Results. It was found that children who were quarantined for COVID-19 (both residents of radioactively contaminated areas and children who do not belong to the contingents affected by the Chornobyl disaster) had an increased level of reactive (RA) and personal anxiety (PA). The comparative analysis showed that children of the same sex of the main group and the comparison group did not differ in terms of PA and RA. At the same time, studies have shown that girls, both in the main group and in the comparison group, were characterized by higher levels of PA and RA than boys. It was determined that poor sleep quality was common in both children living in radioactively contaminated areas (42.71 %) and children in the comparison group (42.44 %). Among the sleep disorders in children of both observation groups, «day dysfunction» was most often detected. Conclusions. There was a direct correlation between the overall PSQI score and the level of reactive, personal anxiety and the overall PSQI score. Using regression analysis, the presence of a linear association of the level of incorporated 137Cs (Bq) with the indicator of personal anxiety of children living in radioactively contaminated territory (b = - 0.716, p < 0.001) was proved. Key words: Chornobyl disaster, COVID-19, quarantine, anxiety, sleep quality.

АККУМУЛЯЦИЯ 137Cs ЛИШАЙНИКОМ HYPOGYMNIA PHYSODES (НА ПРИМЕРЕ ГОМЕЛЬСКОЙ ОБЛАСТИ)

The paper presents the results of determining the 137Cs content in the biomass of the lichen Hypogymnia physodes, which growing in pine forests on the territory of the Gomel region with various levels of radioactive contamination.The research was carried out both in conditionally clean and radioactively contaminated areas with 137Cs soil contamination density from 37 to 1488 kBq m-2. The high accumulating capacity of the lichen Hypogymnia physodes in relation to 137Cs was shown, as well as an increase in the concentration of the radionuclide in the lichens biomass with an increase in the density of soil contamination. Differences in 137Cs accumulation by the lichen Hypogymnia physodes, growing in uneven-aged pine stands, were noted. The lowest concentrations of 137Cs were noted in the samples growing in mature pine forests, while thalli sampled from young pine stands contain significant amounts of the radionuclide.