The Dnieper River headwaters are in Russia’s Valdai Hills and the river flows south to the Black Sea. The Dnieper River provides a waterway in which to transport goods to and from various European nations. In additio...The Dnieper River headwaters are in Russia’s Valdai Hills and the river flows south to the Black Sea. The Dnieper River provides a waterway in which to transport goods to and from various European nations. In addition, the dams on the river provide hydro power. There are approximately 2260 km of Dnieper waterways in Russia, in Belarus, and within Ukraine. The Dnieper River has numerous urban centers including Smolensk in Russia, Mogilev in Belarus and Kiev and Zaporizhzhya in Ukraine. The worst nuclear accident in history unfolded, in the Dnieper River watershed, in northern Ukraine as a reactor at the Chernobyl nuclear power plant exploded and burned. After an accident, such as Chernobyl, radionuclide contaminated bodies of water via direct deposition from the air, discharge as effluent or indirectly from catchment basin washout. When radionuclides contaminate large bodies of water, they are quickly dispersing and accumulate in water bottom sediments, benthos, aquatic plants, and bottom feeding fish. The main pathways to humans are through contamination of drinking-water, from use of water for irrigation of food crops, and consumption of contaminated fish. Kakhovka Dam on the Dnieper River was destroyed during the Russian-Ukraine conflict and the dam needs to rebuild as soon as possible. Perhaps lessons learned by the US Army Corps of Engineers (USACE), after using TNT to blow up the Birds Point front line levee on the Mississippi River in May of 2011, can be applied to the man-induced 2023 Kakhovka Dam breach. The Birds Point man-induced levee breaches and subsequent flooding of farmland resulted in the loss of the 2011 crops and damaged the future soil productivity. The strong current and sweep of the water through the three man-induced levee breaches on the New Madrid floodway levee created deep gullies, displaced tons of soil, and damaged irrigation equipment, farms, and homes. The New Madrid floodway agricultural lands were restored, and the environmental damages were mitigated. The Kakhovka Dam destructi展开更多
A large amount of radioactivity was released into the environment after the Fukushima nuclear accident （FNA） in Japan in 2011. This radioactivity had a significant impact on the global environment, and there was muc...A large amount of radioactivity was released into the environment after the Fukushima nuclear accident （FNA） in Japan in 2011. This radioactivity had a significant impact on the global environment, and there was much public concern about its effects. The subsequent assessment of the FNA and the environmental remediation required are proving to be long and complicated tasks. The assessments are based on the radioactive source terms for the FNA, which determine the level of damage caused by the nuclear accident. We investigated the radioactive source terms from three aspects： the amount and composition of the radionuclides; the activity and atomic ratio of the radionuclides; and comparison with other historical events. The total amount of radioactivity, excluding the radioactive noble gases （85Kr and 133Xe）, released by the FNA was about 10% of that released by the Chernobyl nuclear accident in 1986 and 〈1%o of the global fallout from the atmosphere nuclear explosion. However, the FNA was the most serious nuclear accident in terms of radioactive pollution of the marine environment. The recovery actions carried out after the FNA have been evaluated and the environmental impacts of the FNA are discussed.展开更多
The comparative study of technogenic ^(90)Sr behavior features in Crimea lakes’ ecosystems with different levels of salinity was carried out in 2016-2021.Two sources of ^(90)Sr input were identified for all the studi...The comparative study of technogenic ^(90)Sr behavior features in Crimea lakes’ ecosystems with different levels of salinity was carried out in 2016-2021.Two sources of ^(90)Sr input were identified for all the studied lakes:the primary source concerned with atmospheric fallout immediately after the Chernobyl NPP accident and the secondary long-term input of this radionuclide by waterway.The half-life of the ^(90)Sr concentration in the water of the hypers aline Lake Sasyk-Sivash was estimated to vary from 0.8 to 1.1 years after the closure of the North Crimean Canal(NCC).Biogeochemical processes in the lake under the absence of the secondary source of the radionuclide input were shown to decrease in the ^(90)Sr residence time in the water column by 131 times.For brackish water bodies,a significant factor influencing the radionuclide concentration in ecosystems of lakes was the pH of their water,while for hypers aline lakes the level of water salinity was the main factor determining ^(90)Sr behavior.The concentration of ^(90)Sr in bottom sediments of studied lakes depended mainly on this radionuclide concentration in a water environment.Calculated ^(90)Sr distribution factors(Kd) for studied lakes’ bottom sediments varied in a range of n·10^(0)÷n·10^(2) for hypersaline lakes and of n·10^(1)÷n·10^(2) for lakes with brackish waters.Due to the closure of the NCC,the ^(90)Sr redistribution took place in lake ecosystems only under the geochemical processes within the water bodies themselves.The results obtained in this work are of particular importance as a starting point or a basis for further radioecological studies of the Crimean inland waters after the reopening of the NCC and the Dnieper waters re-entering the territory of Crimea in 2022after the 8 years of their absence.展开更多
Investigations of ^(239+240)Pu and ^(238)Pu in the surface layer(0–5 cm) of bottom sediment in the Crimean 10 salt lakes from 4 geographical groups were carried out for the first time. The ^(239+240)Pu varied widely ...Investigations of ^(239+240)Pu and ^(238)Pu in the surface layer(0–5 cm) of bottom sediment in the Crimean 10 salt lakes from 4 geographical groups were carried out for the first time. The ^(239+240)Pu varied widely between regional geographical groups of lakes as well as within groups too and ranged from 11±4 to 451±43 mBq^(239+240)Pu/kg. The highest levels of ^(239+240)Pu—419±27, 443±24 and 451±43 mBq/kg were observed in the Yevpatoriya(Lake Kyzyl-Yar), the Tarkhankut(Dzharylhach) and the Kerch group(Tobechik), respectively. The lowest values of ^(239+240)Pu were identified in three lakes of the Perekop group and were 20±12, 24±6 and 48±6 mBq/kg. In all lakes ^(238)Pu was an order of magnitude lower than 239+240 Pu and varied from 4.8±2.6 to 30.7±5.5 mBq/kg. The ^(238)Pu activity was decay-corrected to 1986. The characteristic ratio of the ^(238)Pu/239+240 Pu activities in the sediment and percentage of the Chernobyl-derived Pu was calculated. The largest percentages of the Chernobyl-derived Pu were observed in the Evpatoriya group(Lake SasykSivash)—16.2%±8.26%, the Tarkhankut group(Dzharylhach)—8.4%±2.10% and the Kerch group(Aktash)—10.5%±5.56%. The study of the depth distribution of plutonium in the Lake Kyzyl-Yar bottom sediment core(0–25 cm) was fulfilled. It was shown that 239+240 Pu was high enough in all studied layers of bottom sediment, but the highest activity ratio ^(238)Pu/239+240 Pu(0.062±0.020) was found in the deepest layer of 15–20.5 cm and the percentage of Chernobyl-derived Pu was estimated at 6.8%±2.85% in this layer.展开更多
In this work, we addressed the inhomogeneity problem in gamma spectrometry caused by hot particles, which are dispersed into environment from large nuclear reactor accidents such as at Chernobyl and Fukushima. Using M...In this work, we addressed the inhomogeneity problem in gamma spectrometry caused by hot particles, which are dispersed into environment from large nuclear reactor accidents such as at Chernobyl and Fukushima. Using Monte Carlo simulation, we have determined the response of a gamma spectrometer to individual and grouped hot particles randomly distributed in a soil matrix of 1-L and 0.6-L sample containers. By exploring the fact that the peak-to-total ratio of efficiencies in gamma spectrometry is an empirical parameter, we derived and verified a power-law relationship between the peak efficiency and peak-to-total ratio. This enabled creation of a novel calibration model which was demonstrated to reduce the bias range and bias standard deviation, caused by measuring hot particles, by several times, as compared with the homogeneous calibration. The new model is independent of the number, location, and distribution of hot particles in the samples. In this work, we demonstrated successful performance of the model for a single-peak <sup>137</sup>Cs radionuclide. An extension to multi-peak radionuclide was also derived.展开更多
1 Introduction The salt lakes of the Crimea contain the practically inexhaustible sources of salts of sodium,magnesium,bromine and other chemical elements(Ponizovskii,1965),being the potential powerful raw materials b...1 Introduction The salt lakes of the Crimea contain the practically inexhaustible sources of salts of sodium,magnesium,bromine and other chemical elements(Ponizovskii,1965),being the potential powerful raw materials base for the展开更多
Branch and main stem defects of horsechestnut trees (Aesculus hippocastanum L.) in Pripyat, Ukraine, abandoned in 1986, and un-maintained since then, were compared to managed trees of the same species and similar age ...Branch and main stem defects of horsechestnut trees (Aesculus hippocastanum L.) in Pripyat, Ukraine, abandoned in 1986, and un-maintained since then, were compared to managed trees of the same species and similar age in the city of Kiev, Ukraine. Trees in Kiev sustained more trunk injuries, and numerous pruning wounds, and developed significantly more branch defects (especially codominant stems) in their canopies compared to trees in Pripyat. Although Kiev trees had larger stem diameters, the overall quality of their form was reduced compared to street trees in Pripyat. Pripyat horsechestnuts grew with competition from other, invading trees thus, experienced shading of their lower canopies and significant competition for light and had smaller bole diameters. Effects of the Chernobyl nuclear disaster on trees in the Nuclear Exclusion Zone are also discussed.展开更多
The research of degree of incidence of genomic changes (of micronuclei) in mucous cells of gastric superficial-foveolar epithelium in contaminated and not contaminated mucous of stomach was made. Histopathological res...The research of degree of incidence of genomic changes (of micronuclei) in mucous cells of gastric superficial-foveolar epithelium in contaminated and not contaminated mucous of stomach was made. Histopathological research of micronuclei and helicobacter was made in gastric biopsy specimen of patients with diagnosis-chronical gastritis (ICD-10K29.3) in group of patients who lived in radiation contaminated areas and in groups of people, who had no factors of radiation influence in anamnesis. People, who lived in the radiation contaminated areas, whose mucous was infected by Helicobacter pylori, had the highest frequency of mucous cells with micronuclei. In the group of patients from radiation contaminated areas with HP-associated gastritis frequency of appearance of mucous cells with micronucleus in the mucous of stomach have five time more, than patients, whose mucous of stomach was not infected (p Helicobacter pylori can success in mutagenic effect of radiation factor.展开更多
Agricultural land use in the area of the post-Chemobyl Plavsk radioactive hotspot (Tula region,Central Russia) has raised a problem of radioecological safety of obtained plant foodstuff.Verification of 137Cs activitie...Agricultural land use in the area of the post-Chemobyl Plavsk radioactive hotspot (Tula region,Central Russia) has raised a problem of radioecological safety of obtained plant foodstuff.Verification of 137Cs activities and inventories in components of 'soil-plant' systems of the territory has been conducted in 2014-2017 in 10 agrosystems and 2 semi-natural meadows.It was revealed that density of 137Cs contamination of arable chernozems and alluvial calcareous soils nowadays varies in a range 140-220 kBq/m2 and exceeds radiation safety standard by^3.5-6 times.Deep plowing of the arable soils up to 30-cm in 1986-1987 resulted in decreasing of 137Cs inventories in rooting zone by ≈ 70% for crops cultivated with shallow disk plowing (wheat,barley),and by ≈ 35% for crops cultivated with middle plowing (buckwheat,amaranth,white mustard).The investigated plants and their compartments can be grouped on the basis of transfer factor values as follows:maize (stems and leaves)> amaranth> bromegrass > vegetation of dry meadow,galega,sunflower (seeds),vegetation of wet meadow > maize (grain),soybean (pods),barley (grain),buckwheat (grain),potatoes (tubers)> white mustard (seeds),wheat (grain).It is noticeable that generative plant compartments are characterized by less 137Cs activities in comparison with stems and leaves;and that 137Cs root uptake is not coincide with total flux of mineral nutrients in 'soil-plant' systems.In sum,137Cs soil-to-plant transfer in the area of the Plavsk radioactive hotspot is characterized by considerable discrimination,so 137Cs activities in plants are completely in accordance with national standards.展开更多
文摘The Dnieper River headwaters are in Russia’s Valdai Hills and the river flows south to the Black Sea. The Dnieper River provides a waterway in which to transport goods to and from various European nations. In addition, the dams on the river provide hydro power. There are approximately 2260 km of Dnieper waterways in Russia, in Belarus, and within Ukraine. The Dnieper River has numerous urban centers including Smolensk in Russia, Mogilev in Belarus and Kiev and Zaporizhzhya in Ukraine. The worst nuclear accident in history unfolded, in the Dnieper River watershed, in northern Ukraine as a reactor at the Chernobyl nuclear power plant exploded and burned. After an accident, such as Chernobyl, radionuclide contaminated bodies of water via direct deposition from the air, discharge as effluent or indirectly from catchment basin washout. When radionuclides contaminate large bodies of water, they are quickly dispersing and accumulate in water bottom sediments, benthos, aquatic plants, and bottom feeding fish. The main pathways to humans are through contamination of drinking-water, from use of water for irrigation of food crops, and consumption of contaminated fish. Kakhovka Dam on the Dnieper River was destroyed during the Russian-Ukraine conflict and the dam needs to rebuild as soon as possible. Perhaps lessons learned by the US Army Corps of Engineers (USACE), after using TNT to blow up the Birds Point front line levee on the Mississippi River in May of 2011, can be applied to the man-induced 2023 Kakhovka Dam breach. The Birds Point man-induced levee breaches and subsequent flooding of farmland resulted in the loss of the 2011 crops and damaged the future soil productivity. The strong current and sweep of the water through the three man-induced levee breaches on the New Madrid floodway levee created deep gullies, displaced tons of soil, and damaged irrigation equipment, farms, and homes. The New Madrid floodway agricultural lands were restored, and the environmental damages were mitigated. The Kakhovka Dam destructi
基金China Polar Science Strategy Foundation(Grant No.20120316)Tsinghua University Initiative Scientific Research Program(Grant No.20111080965)the National Natural Science Foundation of China(Grant Nos.11205094&41106167)
文摘A large amount of radioactivity was released into the environment after the Fukushima nuclear accident （FNA） in Japan in 2011. This radioactivity had a significant impact on the global environment, and there was much public concern about its effects. The subsequent assessment of the FNA and the environmental remediation required are proving to be long and complicated tasks. The assessments are based on the radioactive source terms for the FNA, which determine the level of damage caused by the nuclear accident. We investigated the radioactive source terms from three aspects： the amount and composition of the radionuclides; the activity and atomic ratio of the radionuclides; and comparison with other historical events. The total amount of radioactivity, excluding the radioactive noble gases （85Kr and 133Xe）, released by the FNA was about 10% of that released by the Chernobyl nuclear accident in 1986 and 〈1%o of the global fallout from the atmosphere nuclear explosion. However, the FNA was the most serious nuclear accident in terms of radioactive pollution of the marine environment. The recovery actions carried out after the FNA have been evaluated and the environmental impacts of the FNA are discussed.
基金Scientific research on salt and brackish water lakes was supported by the Russian Science Foundation,with grant No.18-16-00001Development of biological and geochemical foundations for the development of aquaculture in hypersaline lakes and lagoons of Crimea,2021-2022Comparative studies on the Black Sea were carried out within the framework of the State Assignment for the IBSS,Molismological and biogeochemical foundations of the homeostasis of marine ecosystems,with State registration number of the state assignment 121031500515-8。
文摘The comparative study of technogenic ^(90)Sr behavior features in Crimea lakes’ ecosystems with different levels of salinity was carried out in 2016-2021.Two sources of ^(90)Sr input were identified for all the studied lakes:the primary source concerned with atmospheric fallout immediately after the Chernobyl NPP accident and the secondary long-term input of this radionuclide by waterway.The half-life of the ^(90)Sr concentration in the water of the hypers aline Lake Sasyk-Sivash was estimated to vary from 0.8 to 1.1 years after the closure of the North Crimean Canal(NCC).Biogeochemical processes in the lake under the absence of the secondary source of the radionuclide input were shown to decrease in the ^(90)Sr residence time in the water column by 131 times.For brackish water bodies,a significant factor influencing the radionuclide concentration in ecosystems of lakes was the pH of their water,while for hypers aline lakes the level of water salinity was the main factor determining ^(90)Sr behavior.The concentration of ^(90)Sr in bottom sediments of studied lakes depended mainly on this radionuclide concentration in a water environment.Calculated ^(90)Sr distribution factors(Kd) for studied lakes’ bottom sediments varied in a range of n·10^(0)÷n·10^(2) for hypersaline lakes and of n·10^(1)÷n·10^(2) for lakes with brackish waters.Due to the closure of the NCC,the ^(90)Sr redistribution took place in lake ecosystems only under the geochemical processes within the water bodies themselves.The results obtained in this work are of particular importance as a starting point or a basis for further radioecological studies of the Crimean inland waters after the reopening of the NCC and the Dnieper waters re-entering the territory of Crimea in 2022after the 8 years of their absence.
基金supported by the Russian Foundation for Basic Research Grant No.16-05-00134
文摘Investigations of ^(239+240)Pu and ^(238)Pu in the surface layer(0–5 cm) of bottom sediment in the Crimean 10 salt lakes from 4 geographical groups were carried out for the first time. The ^(239+240)Pu varied widely between regional geographical groups of lakes as well as within groups too and ranged from 11±4 to 451±43 mBq^(239+240)Pu/kg. The highest levels of ^(239+240)Pu—419±27, 443±24 and 451±43 mBq/kg were observed in the Yevpatoriya(Lake Kyzyl-Yar), the Tarkhankut(Dzharylhach) and the Kerch group(Tobechik), respectively. The lowest values of ^(239+240)Pu were identified in three lakes of the Perekop group and were 20±12, 24±6 and 48±6 mBq/kg. In all lakes ^(238)Pu was an order of magnitude lower than 239+240 Pu and varied from 4.8±2.6 to 30.7±5.5 mBq/kg. The ^(238)Pu activity was decay-corrected to 1986. The characteristic ratio of the ^(238)Pu/239+240 Pu activities in the sediment and percentage of the Chernobyl-derived Pu was calculated. The largest percentages of the Chernobyl-derived Pu were observed in the Evpatoriya group(Lake SasykSivash)—16.2%±8.26%, the Tarkhankut group(Dzharylhach)—8.4%±2.10% and the Kerch group(Aktash)—10.5%±5.56%. The study of the depth distribution of plutonium in the Lake Kyzyl-Yar bottom sediment core(0–25 cm) was fulfilled. It was shown that 239+240 Pu was high enough in all studied layers of bottom sediment, but the highest activity ratio ^(238)Pu/239+240 Pu(0.062±0.020) was found in the deepest layer of 15–20.5 cm and the percentage of Chernobyl-derived Pu was estimated at 6.8%±2.85% in this layer.
文摘In this work, we addressed the inhomogeneity problem in gamma spectrometry caused by hot particles, which are dispersed into environment from large nuclear reactor accidents such as at Chernobyl and Fukushima. Using Monte Carlo simulation, we have determined the response of a gamma spectrometer to individual and grouped hot particles randomly distributed in a soil matrix of 1-L and 0.6-L sample containers. By exploring the fact that the peak-to-total ratio of efficiencies in gamma spectrometry is an empirical parameter, we derived and verified a power-law relationship between the peak efficiency and peak-to-total ratio. This enabled creation of a novel calibration model which was demonstrated to reduce the bias range and bias standard deviation, caused by measuring hot particles, by several times, as compared with the homogeneous calibration. The new model is independent of the number, location, and distribution of hot particles in the samples. In this work, we demonstrated successful performance of the model for a single-peak <sup>137</sup>Cs radionuclide. An extension to multi-peak radionuclide was also derived.
文摘1 Introduction The salt lakes of the Crimea contain the practically inexhaustible sources of salts of sodium,magnesium,bromine and other chemical elements(Ponizovskii,1965),being the potential powerful raw materials base for the
文摘Branch and main stem defects of horsechestnut trees (Aesculus hippocastanum L.) in Pripyat, Ukraine, abandoned in 1986, and un-maintained since then, were compared to managed trees of the same species and similar age in the city of Kiev, Ukraine. Trees in Kiev sustained more trunk injuries, and numerous pruning wounds, and developed significantly more branch defects (especially codominant stems) in their canopies compared to trees in Pripyat. Although Kiev trees had larger stem diameters, the overall quality of their form was reduced compared to street trees in Pripyat. Pripyat horsechestnuts grew with competition from other, invading trees thus, experienced shading of their lower canopies and significant competition for light and had smaller bole diameters. Effects of the Chernobyl nuclear disaster on trees in the Nuclear Exclusion Zone are also discussed.
文摘The research of degree of incidence of genomic changes (of micronuclei) in mucous cells of gastric superficial-foveolar epithelium in contaminated and not contaminated mucous of stomach was made. Histopathological research of micronuclei and helicobacter was made in gastric biopsy specimen of patients with diagnosis-chronical gastritis (ICD-10K29.3) in group of patients who lived in radiation contaminated areas and in groups of people, who had no factors of radiation influence in anamnesis. People, who lived in the radiation contaminated areas, whose mucous was infected by Helicobacter pylori, had the highest frequency of mucous cells with micronuclei. In the group of patients from radiation contaminated areas with HP-associated gastritis frequency of appearance of mucous cells with micronucleus in the mucous of stomach have five time more, than patients, whose mucous of stomach was not infected (p Helicobacter pylori can success in mutagenic effect of radiation factor.
文摘Agricultural land use in the area of the post-Chemobyl Plavsk radioactive hotspot (Tula region,Central Russia) has raised a problem of radioecological safety of obtained plant foodstuff.Verification of 137Cs activities and inventories in components of 'soil-plant' systems of the territory has been conducted in 2014-2017 in 10 agrosystems and 2 semi-natural meadows.It was revealed that density of 137Cs contamination of arable chernozems and alluvial calcareous soils nowadays varies in a range 140-220 kBq/m2 and exceeds radiation safety standard by^3.5-6 times.Deep plowing of the arable soils up to 30-cm in 1986-1987 resulted in decreasing of 137Cs inventories in rooting zone by ≈ 70% for crops cultivated with shallow disk plowing (wheat,barley),and by ≈ 35% for crops cultivated with middle plowing (buckwheat,amaranth,white mustard).The investigated plants and their compartments can be grouped on the basis of transfer factor values as follows:maize (stems and leaves)> amaranth> bromegrass > vegetation of dry meadow,galega,sunflower (seeds),vegetation of wet meadow > maize (grain),soybean (pods),barley (grain),buckwheat (grain),potatoes (tubers)> white mustard (seeds),wheat (grain).It is noticeable that generative plant compartments are characterized by less 137Cs activities in comparison with stems and leaves;and that 137Cs root uptake is not coincide with total flux of mineral nutrients in 'soil-plant' systems.In sum,137Cs soil-to-plant transfer in the area of the Plavsk radioactive hotspot is characterized by considerable discrimination,so 137Cs activities in plants are completely in accordance with national standards.
