Radiocesium wash-off, river transport and redistribution in fluvial system after the Fukushima Dai-ichi nuclear power plant accident

2020 ◽  
Author(s):  
Aleksei Konoplev ◽  
Yoshifumi Wakiyama ◽  
Toshihiro Wada ◽  
Valentin Golosov ◽  
Maxim Ivanov ◽  
...  
Keyword(s):  
Bottom Sediments ◽  
Water Samples ◽  
Sediment Cores ◽  
Speciation Analysis ◽  
Water Bodies ◽  
Fukushima Accident ◽  
River Transport ◽  
Dam Reservoirs ◽  
Extreme Flood

<p>Processes responsible for long-term changes in environmental radioactivity after the Fukushima accident are currently high on the agenda. Dynamics of particulate and dissolved radiocesium (r-Cs) has been studied on a number of water bodies, namely Abukuma River, Niida River and Maeda River, the dam reservoirs of Yokokawa (Ota River), Sakashita (Kuma River), Ogaki (Ukedo River) and Shinobu (Abukuma River) and four heavily contaminated irrigation ponds in Okuma town (Inkyozaka, Suzuuchi, Funasawa, Kashiramori). Water samples were collected for dissolved and particulate r-Cs analysis at multiple sites for these water bodies. Wash-off from slopes of contaminated catchments and river transport are key long-term pathways for radionuclide dispersal from contaminated areas after the Fukushima accident. The climate and geographical conditions for the Fukushima Prefecture of Japan are characterized by relatively high annual precipitation (1300-1800 mm/year) and steep slopes which promote higher erosion and higher particulate r-Cs wash-off. At the same time, the r-Cs distribution coefficient <em>K<sub>d</sub></em> in Fukushima rivers was found to be at least an order of magnitude higher than the corresponding values for Chernobyl-derived r-Cs and r-Cs resulting from nuclear weapon tests (NWT) in European rivers. The normalized dissolved wash-off coefficient for Fukushima river watersheds, based on the measured dissolved r-Cs activity concentrations was found to be 1-2 orders of magnitude lower than those for Chernobyl and NWT fallout. In the irrigation ponds r-Cs showed a persistent behavior and was characterized by regular seasonal variations: r-Cs concentrations tend to grow during summer and decrease during winter. Speciation analysis for Okuma ponds showed a much higher exchangeability of r-Cs in bottom sediments than catchment soils. Several methodologies to collect water samples and to separate the particulate and dissolved fractions have been used and showed comparable results for all water bodies under study. For all rivers, reservoirs, and ponds higher values of <em>K<sub>d</sub></em>(r-Cs) have been confirmed when compared with Chernobyl-derived r-Cs in European water bodies. Some observations demonstrated remobilization of r-Cs at river mouths compared to upstream sections which could be explained by the change of river water hydrochemistry from upstream to the mouth, specifically a substantial increase in the concentration of major r-Cs competing cations for selective sorption sites on the suspended matter. Some dam reservoirs and ponds were subjected to integrated suspended sediment sampling. For the dam reservoirs, the particulate r-Cs activity concentration has been found to be water depth-dependent. Sediment cores collected at eight sites along the Abukuma river floodplain in 2018 and during October-November 2019, right after Typhoon Hagibis occurred in the middle of October 2019, demonstrated substantial redistribution of r-Cs due to erosion and redeposition during heavy rainfall and extreme flood. Bottom sediments coring in the dam reservoirs allowed estimation of the average sedimentation rate in the reservoirs and the rate of r-Cs accumulation. This research was partially supported by the Japan Society for the Promotion of Science (JSPS), Grant-in-aid for Scientific Research (B) (18H03389), bilateral project No. 18-55-50002 of Russian Foundation for Basic Research (RFBR) and JSPS.</p>

scholarly journals Reconstruction of the Long-Term Dynamics of Particulate Concentrations and Solid–Liquid Distribution of Radiocesium in Three Severely Contaminated Water Bodies of the Chernobyl Exclusion Zone Based on Current Depth Distribution in Bottom Sediments

Land ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 29
Author(s):  
Alexei Konoplev ◽  
Gennady Laptev ◽  
Yasunori Igarashi ◽  
Hrigoryi Derkach ◽  
Valentin Protsak ◽  
...  
Keyword(s):  
Bottom Sediments ◽  
Sediment Cores ◽  
Temporal Trends ◽  
Water Bodies ◽  
Contaminated Water ◽  
Exclusion Zone ◽  
Liquid Distribution ◽  
Diffusional Model ◽  
Solid Liquid

Given the importance of understanding long-term dynamics of radionuclides in the environment in general, and major gaps in the knowledge of 137Cs particulate forms in Chernobyl exclusion zone water bodies, three heavily contaminated water bodies (Lakes Glubokoe, Azbuchin, and Chernobyl NPP Cooling Pond) were studied to reconstruct time changes in particulate concentrations of 137Cs and its apparent distribution coefficient Kd, based on 137Cs depth distributions in bottom sediments. Bottom sediment cores collected from deep-water sites of the above water bodies were sliced into 2 cm layers to obtain 137Cs vertical profile. Assuming negligible sediment mixing and allowing for 137Cs strong binding to sediment, each layer of the core was attributed to a specific year of profile formation. Using this method, temporal trends for particulate 137Cs concentrations in the studied water bodies were derived for the first time and they were generally consistent with the semiempirical diffusional model. Based on the back-calculated particulate 137Cs concentrations, and the available long-term monitoring data for dissolved 137Cs, the dynamics of 137Cs solid–liquid distribution were reconstructed. Importantly, just a single sediment core collected from a lake or pond many years after a nuclear accident seems to be sufficient to retrieve long-term dynamics of contamination.

Long-term stability of water samples— reanalysis of 20-year-old unpreserved samples

2019 ◽  
Vol 193 (2) ◽  
pp. 167-171
Author(s):  
Espen Enge
Keyword(s):  
Ambient Temperature ◽  
Water Samples ◽  
Water Bodies ◽  
Total Hardness ◽  
Term Stability ◽  
Long Term Stability ◽  
Long Term Storage ◽  
Stability Of Water ◽  
Term Storage

The current study compiles data from the reanalysis of 25 water samples stored unpreserved at ambient temperature for 20 years. Small changes in pH, conductivity and chloride and no significant effects on Al and total hardness were detected. The small effects measured, even during long-term storage under unsuitable conditions, suggest that samples taken from pristine water bodies remain chemically stable over many years.

Artificial radionuclides, mercury, lead, and oil components in sediment cores as markers of the Anthropocene Epoch

2021 ◽  
Author(s):  
Yury Fedorov ◽  
Andrey Kuznetsov ◽  
Irinageo Dotsenko ◽  
Anna Mikhailenko
Keyword(s):  
Bottom Sediments ◽  
Working Group ◽  
Anthropogenic Impact ◽  
Sediment Cores ◽  
Water Bodies ◽  
Sedimentation Rates ◽  
Sea Of Azov ◽  
The Holocene ◽  
The Sea Of Azov ◽  
Oil Components

<p>The majority of researches of the Working group on the ‘Anthropocene’ of the International Commission on Stratigraphy (ICS) voted for the recognition of the Anthropocene as a formal chrono-stratigraphic unit characterized by profound alterations of several conditions and processes on Earth by human impact. It is also proposed to place its beginning and the end of the Holocene epoch in the mid-20th century, coinciding with the launch of nuclear weapon tests [1]. In contemporary sediment cores of the Sea of ​​Azov, the Don and the Kuban rivers, we will distinguish a "layer of anthropogenic impact", meaning the layer containing considerable quantities of technogenic material and (or) pollutants [2]. To reveal the chronology of its formation, its thickness, and boundaries, it is proposed to use the results of layer-by-layer determining of the Cs-137 and Am-241 specific activities, as well as the content of oil components, lead and mercury in the bottom sediments of the water bodies. The upper Cs-137 peak formed due to the Chernobyl accident and sometimes the lower Cs-137 and Am-241 peaks related to the global radioactive fallout in the 1950s and 1960s have been detected [3]. The decrease of mercury, lead, and oil components concentrations from the upper to the lower parts of sediment cores has also been observed. The results of analysis of technogenic radionuclides and priority pollutants distribution have proved that since the 1950s and 1960s in the bottom sediments of the Sea of ​​Azov and water bodies of its basin the “layer of anthropogenic impact" has been being formed. Its thickness varies from 20 to 50 cm and may even exceed 50 cm in areas characterized by high sedimentation rates. It has been found out that in the mid-20th century the ecosystem of the Sea of ​​Azov began to suffer from intense anthropogenic pressure, which reached its maximum in the 1970s and 1980s. It is proposed to consider the studied pollutants (technogenic radionuclides, mercury, lead, and oil components) as a possible set of priority markers of the Anthropocene epoch. The Holocene - Anthropocene boundary should be placed at the base of the identified “layer of anthropogenic impact”.</p><p> </p><p>The research was supported by the Russian Foundation for Basic Research, project no. 19-05-50097.</p><p> </p><p>Bibliography</p><p>[1] Working Group on the ‘Anthropocene’. Results of binding vote by AWG. http://quaternary.stratigraphy.org/working-groups/anthropocene/ (last accessed 17 January 2021).</p><p>[2] Kuznetsov A.N., Fedorov Yu.A., and Yaroslavtsev V.M. (2018) Technogenic and natural radionuclides in the bottom sediments of the Sea of Azov: regularities of distribution and application to the study of pollutants accumulation chronology. IOP Conference Series: Earth and Environmental Science 107, 012063.</p><p>[3] Fedorov Yu.A., Kuznetsov A.N., and Trofimov M.E. (2008) Sedimentation rates in the Sea of Azov inferred from Cs-137 and Am-241 specific activity. Doklady Earth Sciences, vol. 423, no. 1, pp. 1333-1334.</p>

A comparison between the water quality of the main tributaries to three submontane dam reservoirs and the sediment quality in those reservoirs

2010 ◽  
Vol 39 (3) ◽  
Author(s):  
Ewa Szarek-Gwiazda ◽  
Grażyna Mazurkiewicz-Boroń
Keyword(s):  
Water Quality ◽  
Organic Matter ◽  
Bottom Sediments ◽  
Water Samples ◽  
Sediment Quality ◽  
Alkaline Ph ◽  
River Waters ◽  
Dam Reservoirs

A comparison between the water quality of the main tributaries to three submontane dam reservoirs and the sediment quality in those reservoirsNutrients, pH, and organic matter were determined in water samples collected from the Raba River above Dobczyce Reservoir (meso-eutrophic), from the Dunajec River above Czorsztyn Reservoir (mesotrophic), and Rożnów Reservoir (eutrophic), and in the bottom sediments of the reservoirs. The river waters were alkaline (pH 7.2-9.2). In the Raba River and Dunajec River, the ranges of nutrients and organic matter contents were similar (without significant differences) (in mg dm

Oxygen Regime of the Water Bodies as Main Factor of Different Metals Forms Migration within the System “Bottom Sediments - Water”

2009 ◽  
Vol 45 (2) ◽  
pp. 85-105 ◽  
Author(s):  
P. N. Linnik ◽  
O. V. Timchenko ◽  
A. V. Zubko ◽  
I. B. Zubenko ◽  
L. A. Malinovskaya
Keyword(s):  
Bottom Sediments ◽  
Water Bodies ◽  
Oxygen Regime ◽  
Main Factor

ANALYSIS OF ACCUMULATION AND DISTRIBUTION OF LEAD IN THE SYSTEM WATER-BOTTOM SEDIMENTS IN THE BACH DANG ESTUARY (VIETNAM)

2017 ◽  
pp. 62-66
Author(s):  
Truong Van Tuan ◽  
Irina Vladimirovna Volkova
Keyword(s):  
Bottom Sediment ◽  
Bottom Sediments ◽  
Water Samples ◽  
Suspended Solids ◽  
Natural Habitat ◽  
Bottom Layer ◽  
Sediment Samples ◽  
Natural Breeding ◽  
System Water ◽  
Water Bottom

Research was held in the estuary of the river Bach Dang (Dongbay community, Rakhtay district, Hai Phong, Vietnam) in June, 2012 - May, 2013. Concentration of lead was studied in water, suspended solids and bottom sediment. Clam beach (natural breeding environment of Meretrix lyrata ) was inspected regularly, every month. Water samples were taken 6 times from the bottom layer 10 cm down the bottom, once per 3 hours in each of 12 investigated zones. Bottom sediment samples were taken at the depth 2 cm. The findings show that lead accumulates mainly in suspended solids (23.3 mg/kg) and in bottom sediment (14.31 mg/kg), in water it is in small quantities (0.003 mg/kg). Analysis of bottom sediment samples taken in different places showed that they have even leadcontent, lead is distributed uniformly, localization of contaminations is not found. The results obtained can be assumed as the basis for investigating lead accumulation and its excretion by clam Meretrix lyrata organisms in the natural habitat.

SITE-SPECIFIC EQUATIONS OF STATE FOR COASTAL SEA AREAS AND INLAND WATER BODIES

2017 ◽  
Author(s):  
Natalia Andrulionis ◽  
Natalia Andrulionis ◽  
Ivan Zavialov ◽  
Ivan Zavialov ◽  
Elena Kovaleva ◽  
...  
Keyword(s):  
Equation Of State ◽  
Black Sea ◽  
Water Samples ◽  
Equations Of State ◽  
Sea Water ◽  
Ionic Composition ◽  
Water Bodies ◽  
Aral Sea ◽  
The Black Sea ◽  
Coastal Sea

This article presents a new method of laboratory density determination and construction equations of state for marine waters with various ionic compositions and salinities was developed. The validation of the method was performed using the Ocean Standard Seawater and the UNESCO thermodynamic equation of state (EOS-80). Density measurements of water samples from the Aral Sea, the Black Sea and the Issyk-Kul Lake were performed using a high-precision laboratory density meter. The obtained results were compared with the density values calculated for the considered water samples by the EOS-80 equation. It was shown that difference in ionic composition between Standard Seawater and the considered water bodies results in significant inaccuracies in determination of water density using the EOS-80 equation. Basing on the laboratory measurements of density under various salinity and temperature values we constructed a new equation of state for the Aral Sea and the Black Sea water samples and estimated errors for their coefficients.

Sign in / Sign up

Export Citation Format

Share Document