タグ「sediment」
Title: Pu and Am sorption to the Baltic Sea bottom sediments
Author: G. Lujanienė, P. Beneš, K. Štamberg, K. Jokšas, I. Kulakauskaitė
Reference: Journal of Radioanalytical and Nuclear Chemistry , March 2013, Volume 295, Issue 3, pp 1957-1967
DOI: 10.1007/s10967-012-2281-1
Keywords: Pu(IV), Pu(V), Bottom sediments, Seawater, Sorption
Abstract: Sorption of Am and Pu isotopes to bottom sediments of the Baltic Sea has been studied under natural and laboratory conditions. Data obtained from sequential extraction, sorption of Am(III), Pu(IV) and Pu(V) as well as oxidation state distribution experiments have shown that Pu(V) sorption mechanism includes a very fast Pu(V) reduction (reaction rate ≤ 2.33 × 10−3 s−1) to Pu(IV) by humic substances and/or by Fe(II) to Pu(IV) and partly to Pu(III). Following reduction Pu isotopes were bound to various components of bottom sediments via ion exchange and surface complexation reactions and a slow incorporation into the crystalline structure of Fe minerals. Kinetics experiments showed that the sorption of Pu(V), Pu(IV) and Am(III) to bottom sediments from natural seawater was controlled by the inert layer diffusion process.
ＵＲＬ：http://link.springer.com/article/10.1007/s10967-012-2281-1
Title: Long Term Temporal Changes of 90Sr and 137Cs in Seawater, Bottom Sediment and Marine Organism Samples – from the Chernobyl Accident to Immediately after the Fukushima Accident –
Author: Shinji OIKAWA, Teruhisa WATABE, Hyoe TAKATA, Chiyoshi SUZUKI, Motokazu NAKAHARA, Jun MISONOO
Reference: BUNSEKI KAGAKU, Vol. 62 (2013) No. 6 p. 455-474
Doi:http://dx.doi.org/10.2116/bunsekikagaku.62.455
Keywords: radiochemistry, 90Sr, 137Cs, seawater, sediment, marine organism
Abstract: A radioactivity survey program was launched in 1983 to determine the background levels of artificial radionuclides, such as 90Sr and 137Cs in the marine environment off commercial nuclear power stations. In this paper, we report on the long-term temporal changes of 90Sr and 137Cs in seawater, bottom sediment and marine organism samples. Both 90Sr and 137Cs have been detected since the beginning of the program in the seawater samples.
ＵＲＬ：https://www.jstage.jst.go.jp/article/bunsekikagaku/62/6/62_455/_article/-char/ja/
Author: Golubev A.P., Sikorsky V.G., Kalinin V.N., Afonin V.Yu., Chekan G.S.
Reference: Gazette “РАДИАЦИОННАЯ БИОЛОГИЯ. РАДИОЭКОЛОГИЯ “ (Radiation Biology, Radioecology), 2007
ISSN: 0869-8031
DOI: 10.1134/S0869803107030113
Keywords: water bodies, contamination, zoobenthos
Abstract: Long term (1986-2005) observation of dynamics of radionuclide activity in the dominant types of zoobenthos and sediments in reservoirs of the Chernobyl zone- inflow of Pripyat and the non-flowing lake Perstok. Observes the living creatures living in water bodies of the exclusion area of the Chernobyl disaster.
URL: http://elibrary.ru/item.asp?id=9516606
Reference: РЖ 19И. ОБЩИЕ ВОПРОСЫ ХИМИЧЕСКОЙ ТЕХНОЛОГИИ, 2006
Keywords: Rivers and reservoirs, cesium, natural water, sediments, environmental pollution
URL: http://elibrary.ru/item.asp?id=9801599
Title: The role of soil erosion and fluvial processes in the post-fallout redistribution of Chernobyl-derived caesium-137: a case study of the Lapki catchment, Central Russia
Author: A.V Panin, D.E Walling, V.N Golosov
Reference: Geomorphology, Volume 40, Issues 3–4, October 2001, Pages 185-204
DOI: http://dx.doi.org/10.1016/S0169-555X(01)00043-5
Keywords: Chernobyl; Caesium-137; Redistribution; Fluvial processes; Sediment; Soil erosion; Deposition
Abstract: The central area of the Russian Plain received substantial amounts Cs-137 fallout as a result of the Chernobyl accident in 1986, with inventories exceeding 40 kBq m−2 in many of the areas close to Chernobyl. Concern over the longer-term fate of this contamination has focused attention on the need to predict the post-fallout redistribution of the radiocaesium and, thus, future changes in the spatial distribution of contamination in the landscape. Since radiocaesium reaching the land surface as fallout is rapidly and strongly adsorbed by soil and sediment particles, any attempt to predict its post-fallout redistribution must focus on erosion and sediment delivery processes and must rely heavily on a knowledge of the geomorphological processes involved. This paper reports a detailed investigation of post-fallout Cs-137 redistribution in the 2.18-km2 Lapki catchment in the Middle-Russian Upland, which has required consideration of soil erosion processes, sediment delivery pathways, sediment delivery ratios and sediment sinks. The time elapsed since the Chernobyl accident is currently insufficient to result in significant reduction of Cs-137 inventories in eroding areas, but areas of deposition on both the lower slopes and on the balka sides and bottoms are already marked by significant increases in Cs-137 inventories. The results obtained emphasise that any attempt to develop meaningful predictions of the longer-term redistribution of Chernobyl-derived Cs-137 fallout within the Russian Plain must be based on a sound and detailed understanding of the linkage between the slopes and the balka systems and the fate of sediment entering the balka systems.
URL: http://www.sciencedirect.com/science/article/pii/S0169555X01000435
title: The transport and fluvial redistribution of Chernobyl-derived radiocaesium within the River Wye basin, UK
Author: J.S. Rowan, D.E. Walling
Reference: Science of The Total Environment, Volume 121, 30 June 1992, Pages 109-131
DOI: http://dx.doi.org/10.1016/0048-9697(92)90310-O
Keywords: Wye; Chernobyl; radiocaesium; sediment-associated; redistribution
Abstract: Relatively little attention has been given to the long term prospect of fluvial transport processes redistributing Chernobyl-derived radiocaesium within the UK. Work undertaken within the Wye basin, central Wales, demonstrates a complex distribution of fallout at the catchment scale, with the bulk of the deposition concentrated in a narrow north-south band, situated in the west central areas of the basin, which contained in excess of 1500 Bq m−2 of 134Cs. Fluvial transport and redistribution of this material was demonstrated by river sampling during the winter of 1988/89, when the radiocaesium content of suspended sediment transported by the River Wye (≈ 30–50 mBq g−1 of 137Cs) remained 3–5-times higher than pre-Chernobyl levels. Floodplain reaches displayed variable levels of secondary contamination, dependent upon the upstream supply of radiocaesium and local morphological controls. Accordingly, the highest 134Cs inventories within the basin (> 6000 Bq m−2) were associated with rapidly accreting floodplain sites. A number of these sites experienced only limited amounts of direct atmospheric fallout. The importance of fluvial redistribution as a secondary contamination mechanism is thus highlighted.
URL: http://www.sciencedirect.com/science/article/pii/004896979290310O
Title: Accumulation of Chernobyl-derived 137Cs in bottom sediments of some Finnish lakes
Author: Erkki Ilus, Ritva Saxén
Reference: Journal of Environmental Radioactivity, Volume 82, Issue 2, 2005, Pages 199-221
DOI: http://dx.doi.org/10.1016/j.jenvrad.2005.01.008
Keywords: Lake sediments; Chernobyl fallout; Caesium-137; Sedimentation rate
Abstract: The amount and vertical distribution of Chernobyl-derived 137Cs in the bottom sediments of some Finnish lakes were studied. Sediment and surface water samples were taken in 2000 and 2003 from 12 stations in nine lakes and the results were compared with those obtained in corresponding surveys carried out in 1969, 1978, 1988 and 1990. Each of the five deposition categories of Chernobyl fallout in Finland were represented. The depth profiles of 137Cs in the sediments showed considerable variety in the lakes studied. The peak values varied between 1.5 and 46 kBq kg−1 dry wt. The size and shape of the peak did not always correlate with the amount of deposition in the area, but on the other hand, reflected differences in sedimentation processes in different lakes. In some of the lakes the peak still occurred in the uppermost (0–2 cm) sediment layer, but in an extreme case the peak occurred at a depth of 22–23 cm corresponding to a sedimentation rate of 16 mm year−1 during the 14 years after the Chernobyl accident. The total amounts of 137Cs in sediments varied from 15 to 170 kBq m−2 at the sampling stations studied. Since 1990, the amounts have continued to increase slightly in two lakes, but started to decrease in the other lakes. In most of the lakes, the total amounts of 137Cs in sediments were about 1.5–2 times higher than in local deposition. In two lakes, the ratio was below 1, but in one case 3.2. Compared with the total amounts of 137Cs at the same stations in the late 1960s and 1970s, the values were now at their highest, at about 60-fold. The most important factors affecting 137Cs values in sediments were the local amount of deposition and the type of the lake and the sediment, but in addition, there were a number of other factors to be considered.
URL: http://www.sciencedirect.com/science/article/pii/S0265931X0500041X
Title: Recent sedimentation in the Black Sea: New insights from radionuclide distributions and sulfur isotopes.
Author: Yücel, Mustafa; Moore, Willard S.; Butler, Ian B.; Boyce, Adrian; Luther, George W.
Reference: Deep-Sea Research Part I, Oceanographic Research Papers. Aug2012, Vol. 66, p103-113. 11p.
DOI: http://dx.doi.org/10.1016/j.dsr.2012.04.007
Keywords: Black Sea; Sediment; Mass accumulation rate; Pyrite; Sulfur isotope
Abstract: ► Mass accumulation rates (MAR) in the abyssal Black Sea were 61 to 76 g m−2 yr−1. ► These values point to increasing MARs for the past century. ► In the cores with turbidites, we used Chernobyl-derived Cs-137 to compute MAR. ► In turbidite-impacted cores, MAR can be as high as 5230 g m−2 yr−1. ► Fast deposition was reflected in the pyrite sulfur isotopic ratios as well.
URL: http://www.sciencedirect.com/science/article/pii/S096706371200088X
Title: High-resolution historical records from Pettaquamscutt River basin sediments: 1. 210Pb and varve chronologies validate record of 137Cs released by the Chernobyl accident
Author: Lima, Ana Lúcia; Hubeny, J. Bradford; Reddy, Christopher M.; King, John W.; Hughen, Konrad A.; Eglinton, Timothy I.
Reference: Geochimica et Cosmochimica Acta. Apr2005, Vol. 69 Issue 7, p1803-1812. 10p.
DOI: 10.1016/j.gca.2004.10.009.
Keywords: Pettaquamscutt River, 210Pb, 137Cs, sediments
Abstract: Cesium-137 derived from the explosion of the Chernobyl reactor in 1986 was preserved in anoxic sediments from a coastal environment in southern Rhode Island. Although the radioactive plume was detected in surface air samples at several locations in the United States, this is the first known record of a Chernobyl 137Cs peak in sediments from North America. The inventory of Chernobyl 137Cs that was preserved in the Pettaquamscutt River is small compared to European counterparts and should only be detectable for the next 15–20 yr. However, the presence of two 137Cs peaks (1963 and 1987) identifies a well-dated segment of the sediment column that could be exploited in understanding the decomposition and preservation of terrestrial and aquatic organic matter. Different methods for calculating the 210Pb chronology were also evaluated in this study and checked against independent varve counting. The end result is a detailed chronology of a site well suited for reconstruction of historical records of environmental change.
URL: http://www.sciencedirect.com/science/article/pii/S0016703704007975
- Title: Modeling and interpreting element ratios in water and sediments: A sensitivity analysis of post-Chernobyl Ru : Cs ratios
Author: J. Hilton and E. Rigg, W. Davison, J. Hamilton- Taylor, and M. Kelly, F. R. Livens, D. L. Singleton
Reference: Limnol. Oceanogr., 40(7), 1995, 1302-1309
doi:
Keywords:
Abstract: When elements are simultaneously added to lakes, experimentally or by accident, their ratios in the water phase and in bottom sediments can change with time due to differential partitioning between solution and suspended particles or sediments. A number of equations are developed to show the change of ratio with time in water and sediments assuming simultaneous pulse inputs followed by a range of combinations of loss processes from solution
URL: http://eprints.lancs.ac.uk/22278/1/1302.pdf
