scholarly journals Radionuclides distribution and its sorption behavior in the Kara sea bottom sediments surface layer

2019 ◽  
Vol 64 (11) ◽  
pp. 1187-1195
Author(s):  
N. V. Kuzmenkova ◽  
V. V. Krupskaya ◽  
E. V. Duriagina ◽  
I. N. Semenkov ◽  
S. E. Vinokurov
Keyword(s):  
Bottom Sediments ◽  
Sea Water ◽  
Sorption Isotherms ◽  
Sorption Kinetics ◽  
Kara Sea ◽  
Sorption Behavior ◽  
Freundlich Equation ◽  
Sea Bottom ◽  
Complexation Mechanism ◽  
Sorption Characteristics

The sorption characteristics of the Kara sea bottom sediments were investigated. The sediments were collected during scientific expedition of the R/V Akademik Mstislav Keldysh (Cruise AMK-66). The mineral and fraction composition of sediments was determined. It has been found that 137Cs sorbed predominantly by an ion exchange mechanism because of the clay minerals presence in the sediments. At the same time, 243Am and 90Sr sorbed from seawater by the surface complexation mechanism. The sorption kinetics for 243Am was established: about 20 hours, 137Cs: 2 hours, 90Sr: less than an hour. The sorption isotherms shows Cs and Am in experiments on marine and distilled water are described by the Henry equation. The Sr behavior in deionized water is described by the Langmuir equation, in the case of sea water, by the Freundlich equation.

Radionuclides Distribution and its Sorption Behavior in the Surface Layer of the Kara Sea Bottom Sediments

2019 ◽  
Vol 57 (11) ◽  
pp. 1213-1220
Author(s):  
N. V. Kuzmenkova ◽  
V. V. Krupskaya ◽  
E. V. Duriagina ◽  
I. N. Semenkov ◽  
S. E. Vinokurov
Keyword(s):  
Surface Layer ◽  
Bottom Sediments ◽  
Kara Sea ◽  
Sorption Behavior ◽  
Sea Bottom

scholarly journals Bottom Sediments Reveal Inter-Annual Variability of Interaction between the Ob and Yenisei Plumes in the Kara Sea

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
A. A. Osadchiev ◽  
En. E. Asadulin ◽  
A. Yu. Miroshnikov ◽  
I. B. Zavialov ◽  
E. O. Dubinina ◽  
...  
Keyword(s):  
Bottom Sediments ◽  
Vertical Structure ◽  
Suspended Sediments ◽  
Kara Sea ◽  
Local Wind ◽  
River Plumes ◽  
Buoyant Plumes ◽  
Sea Bottom ◽  
Mixing Dynamics ◽  
Good Agreement

AbstractRiver discharge is the main source of terrigenous sediments in many coastal areas adjacent to estuaries and deltas of large rivers. Spreading and mixing dynamics of river plumes governs transport of suspended sediments and their deposition at sea bottom at these areas. Generally river plumes have very large synoptic and seasonal variability, which cannot be reconstructed from structure of bottom sediments due to their small accumulation velocity. However, bottom sediments can be indicative of variability of river plumes on inter-annual and decadal time scales. In this study we focus on the large Ob and Yenisei buoyant plumes formed in the central part of the Kara Sea. These plumes interact and mix in the area adjacent to the closely located Ob and Yenisei gulfs. Suspended sediments carried by these river plumes have significantly different geochemical characteristics that can be used to detect Ob or Yenisei origin of bottom sediments. Using new geochemical methods we revealed dependence between spreading patterns of these plumes and spatial distribution and vertical structure of bottom sediments in the study area. This relation is confirmed by a good agreement between local wind and discharge conditions reconstructed for 1948–2001 and vertical structure of bottom sediments.

Genesis of organic matter in the Kara Sea bottom sediments

Oceanology ◽  
2011 ◽  
Vol 51 (4) ◽  
pp. 608-615 ◽  
Author(s):  
A. A. Vetrov ◽  
E. A. Romankevich
Keyword(s):  
Organic Matter ◽  
Bottom Sediments ◽  
Kara Sea ◽  
Sea Bottom

scholarly journals Sedimentation rates (data on 210pb and 137cs radionuclides) in different facial-genetic types of the Kara sea bottom sediments

2019 ◽  
Vol 64 (11) ◽  
pp. 1158-1174
Author(s):  
V. Yu. Rusakov ◽  
A. P. Borisov ◽  
G. Yu. Solovieva
Keyword(s):  
Bottom Sediments ◽  
Sedimentation Rate ◽  
Isotope Composition ◽  
Original Data ◽  
Kara Sea ◽  
Sedimentation Rates ◽  
Shallow Marine ◽  
Novaya Zemlya ◽  
Genetic Types ◽  
Sea Bottom

In the article original data on isotope composition of natural excess Pb-210 and artificial Cs-137 radionuclides in upper 2550-cm layer of sea-bottom sediments at the Kara Sea (from Ob and Yenisei estuaries, Eastern-Novaya-Zemlya trough, Voronin trough, as well as Sedov bay (Novaya Zemlya)) are presented. The research results showed close tie between sedimentation rates and facial-genetic types of the sea-bottom sediments. Highest sedimentation rates are typical for the terrigenic-estuarine type. The type is divided on tractional load with sedimentation rate 0.40.7 cm per year and mud bank sediments with sedimentation rate 0.71.0 cm per year. The terrigenic-shallow-marine type is characterized by lowest sedimentation rate 0.10.3 cm per year. The background terrigenic-marine type has a broadest spectrum of the sedimentation rates: on trough slope the rates are minimal (likely to terrigenic-shallow-marine type), within central parts of the trough (as a result of gravity creep) the rates may increase up to 0.9 cm per year. Single facial-genetic type is glacial sediments of Navaya Zemlya bays. Measured recent sedimentation rate within inner depression of the Sedov bay is 0.10.2 cm per year.

scholarly journals Content of technogenic radionuclides in water, bottom sediments and benthos of the Kara sea and shallow bays of the Novaya zemlya archipelago

2019 ◽  
Vol 64 (12) ◽  
pp. 1261-1268
Author(s):  
T. A. Goryachenkova ◽  
A. P. Borisov ◽  
G. Yu. Solov`eva ◽  
E. A. Lavrinovich ◽  
I. E. Kazinskaya ◽  
...  
Keyword(s):  
Detection Limit ◽  
Bottom Sediments ◽  
Sea Water ◽  
Global Fallout ◽  
Kara Sea ◽  
Radioactive Cesium ◽  
Novaya Zemlya Archipelago ◽  
Novaya Zemlya ◽  
Open Sea ◽  
Order Of Magnitude

During the expedition on the Akademik Mstislav Keldysh research vessel in 2016 year it was established that the content of radioactive cesium in the sea water of the Novaya Zemlya archipelago bays and open sea are at a level corresponding to the global fallout (1 Bq /m3). Plutonium content in water is slightly higher .The activity of neptunium in water is an order of magnitude higher than the activity of plutonium (0.761.89 Bq/m3), although its content in global fallout is almost two orders of magnitude lower than the plutonium content. The plutonium content in the bottom sediments of the Kara Sea is 0.23.8 Bq/kg. The content of radioactive cesium is as high as possible in the mouth of the Yenisei River (up to 21 Bq/kg) Analysis of benthic samples showed that the content of radioactive cesium and plutonium in samples taken in the bays of the Novaya Zemlya archipelago is below the detection limit. The neptunium content in the benthos samples is above the detection limit and amounts to 180 Bq/kg wet weight. It was showed that the content of neptunium in benthos is one of the indicators of radioactive contamination of the marine environment.

Effects of decalcification on the phosphate sorption characteristics of eight calcareous soils

Soil Research ◽  
1990 ◽  
Vol 28 (6) ◽  
pp. 919 ◽  
Author(s):  
ICR Holford ◽  
M Chater ◽  
GEG Mattingly
Keyword(s):  
Calcareous Soils ◽  
Sorption Isotherms ◽  
Phosphate Sorption ◽  
Surface Equation ◽  
P Sorption ◽  
Surface Areas ◽  
Freundlich Equation ◽  
Sorption Parameters ◽  
Parameter Values ◽  
Sorption Characteristics

Phosphate sorption isotherms and parameter values were determined on eight calcareous soils which were carefully decalcified using a procedure which minimized changes in cation saturation. Calcite content of the original soils varied from 0.8 to 24 2% and calcite surface areas from 4 . 0 to 8.5 m2 g-1. Sorption parameters were derived from the Langmuir 'two-surface' equation. Decalcification increased phosphate sorption at low residual P concentrations (<0.8 mg L-1) but decreased it at higher concentrations. The higher P sorption was associated with an increase in affinity because the calculated sorption capacities of high-affinity surfaces were not increased. These sorption capacities were well correlated with iron oxide contents of the soils, so the increase in phosphate affinity of these surfaces was consistent with the decrease in pH (0.5 to 1.5 units) of the decalcified soils. The lower P sorption at higher concentrations was associated with a substantial decrease in sorption capacity of the postulated low-affinity surfaces. These latter decreases were quantitatively correlated with the calcite surface areas of the original soils. These and other changes in phosphate sorption characteristics support the utility of the Langmuir 'two-surface' equation in providing information, compatible with what would be expected from more complex mechanistic models, and which exceeds what one would expect from other simpler models such as the Freundlich equation. They also support an hypothesis that an important component of low-affinity surfaces of these calcareous soils is calcite on which organic anions are co-adsorbed.

scholarly journals Sorption Characteristics and Fraction Distribution Changes of Selenite in Soil

2018 ◽  
Vol 10 (7) ◽  
pp. 2491 ◽  
Author(s):  
Jianxin Fan ◽  
Guoliang Zhao
Keyword(s):  
Linear Regression ◽  
Sequential Extraction ◽  
Multiple Linear Regression ◽  
Sorption Isotherms ◽  
Sorption Kinetics ◽  
Lower State ◽  
Fraction Distribution ◽  
Pseudo Second Order ◽  
Sorption Parameters ◽  
Sorption Characteristics

Sorption properties play a key role in the mobility of selenium (Se) and fraction distribution changes, leading to the bioavailability of Se in the soil environment. Thus, the effect of soil physicochemical properties on the sorption of exogenous selenite was investigated to predict the rate and capacity of sorption. Correlation analysis and multiple linear regression were used to observe the relationship between sorption characteristics and soil properties. Sequential extraction was used to observe the fractions of Se at different ages in soil. Results indicated that sorption isotherms followed the Langmuir equation, and the sorption capacity ranged from 50.7 to 567 mg·kg−1 with pseudo-second-order sorption kinetics. The correlation and multiple linear regression analyses showed that sorption parameters were significantly positively correlated with dithionite–citrate–bicarbonate-extracted Fe (FeDCB), dithionite–citrate–bicarbonate-extracted Al (AlDCB), amorphous Fe (FeOX), and soil organic matter (SOM), whereas pH was negatively correlated. Sequential extraction analyses revealed that the fraction distribution of Se in soil varied with the age, and the content of elemental Se increased with prolonged aging. FeDCB, AlDCB, FeOX, pH, and SOM play important roles in selenite sorption onto soils. Selenite sorption onto soil can be reduced to a lower-state Se, such as elemental Se and selenides, during the aging process. This information on the environmental behavior of Se is used to develop agronomic strategies for increasing Se levels in food crops and improving human health.

Geochemical signature of bottom sediments in the mixing zones of Ob and Yenisei waters with Kara Sea water

2013 ◽  
Vol 51 (12) ◽  
pp. 1005-1018 ◽  
Author(s):  
En. E. Asadulin ◽  
A. Yu. Miroshnikov ◽  
V. I. Velichkin
Keyword(s):  
Bottom Sediments ◽  
Sea Water ◽  
Kara Sea ◽  
Geochemical Signature

scholarly journals Sorption studies of Cd and Cu on Brazilian alluvial soils

2021 ◽  
Vol 16 (4) ◽  
pp. 1
Author(s):  
Vitor Hugo de Oliveira Barros ◽  
Artur Paiva Coutinho ◽  
Adriana Thays Araújo Alves ◽  
Severino Martins dos Santos Neto ◽  
Fernando Xavier de Assis ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Contaminant Transport ◽  
Sorption Isotherms ◽  
Sorption Kinetics ◽  
Metal Mobility ◽  
Sorption Behavior ◽  
Transport Mechanisms ◽  
Alluvial Aquifers ◽  
Alluvial Sediment ◽  
Pseudo Second Order

The Local Production Arrangement, located in the Pernambuco’s Agreste state, has been significantly developing the region's economy. Despite its importance, industrial activity has caused relevant environmental concerns regarding the disposal of textile effluents, especially from industrial laundries. This waste is made up of many chemicals, and among them are various types of heavy metals. The evaluation of the sorption behavior of contaminant transport mechanisms such as heavy metals is essential to assess the risk of contamination of alluvial aquifers. This study evaluated the sorption of heavy metals (Cu and Cd) in an alluvial sediment deposit in the Capibaribe River. Kinetics and isotherm experiments allowed the analyses of Cu and Cd sorption. Kinetics sorption showed an equilibrium tendency after 16 h for Cu and 18 h for Cd and was better described by a pseudo-second order model. The isotherm data were adjusted to the Linear, Freundlich and Langmuir models. Both linear and Freundlich models satisfactorily described sorption isotherms for the two pollutants. The metals in the study represent a risk of contamination of the groundwater of alluvial aquifers, mainly due to physicochemical attributes of the soil, such as high sand content (85%), low MO (2.1 g kg-1) and alkaline pH (8.2). The environmental conditions decrease absorption and facilitate metal mobility, greatly increasing the environmental risks inherent in pollutant leaching. Cu showed a higher affinity with the soil studied in all assays performed compared with the results of the tests for Cd.

Sorption behaviour of oxadiazon in tropical rice soils

2007 ◽  
Vol 56 (1) ◽  
pp. 115-121 ◽  
Author(s):  
M.E. Hoque ◽  
R.M. Wilkins ◽  
A. Kennedy ◽  
J.A. Garratt
Keyword(s):  
Organic Carbon ◽  
Correlation Coefficient ◽  
Sorption Capacity ◽  
Sorption Isotherms ◽  
Sorption Kinetics ◽  
Rice Soil ◽  
Repeated Application ◽  
Rice Soils ◽  
Sorption Behaviour ◽  
Freundlich Equation

The soprtion behaviour of a pre-emergent herbicide, oxadiazon (5-tert-butyl-3-(2,4-dichloro-5-isopropoxyphenyl)-1,3,4-oxadiazol-2 (3H)-one) was investigated in tropical rice soils using a batch equilibrium method. There is no information available on the fate of oxadiazon in Bangladeshi soils; Bangladesh rice soil is a unique environment. The experiment was performed using radiolabelled (14C) oxadiazon. The sorption and desorption isotherm of oxadiazon was described using the Freundlich equation. L-type sorption isotherms were observed. The correlation coefficient (r2) was 0.995 to 0.997 and the linearity of the slope was in the range 0.96–1.07. Sorption of oxadiazon was related to organic carbon. Sorption of oxadiazon by soil was a rapid process; sorption kinetics indicated that most of the sorption occurred within two hours. Changes in sorption of oxadiazon by soils was investigated by repeated application. Sorption after the first cycle was in the range 81–92% whereas sorption capacity decreased in the following cycles.

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