Hydrocarbons in waters and bottom sediments Of the Barents sea

2021 ◽  
pp. 531-547
Author(s):  
I.A. Nemirovskaya ◽  
◽  
A.M. Titova ◽  
A.V. Khramtsova ◽  
◽  
...  

Hydrocarbons in water, suspended matter and bottom sediments of the Barents Sea were studied based on materials from expeditions to the RV Akademik Mstislav Keldysh in 2016–2019. It is shown that at present there is no oil pollution in open areas of the Barents Sea. With the transition from early summer (2019) to autumn (2016), there was a decrease in hydrocarbon concentrations in surface waters, caused by a change in the biochemical composition of organic matter (possibly due to a decrease in the area of ice). With depth, the HC content decreased mainly. An exception was observed in the area of gutters and deposits, where in the bottom nepheloid layers there was an increase in the concentration of hydrocarbons in suspension and in the surface layer of bottom sediments, and in the thickness of the sediments there was no dependence on their distribution and organic carbon.

Oceanology ◽  
2020 ◽  
Vol 60 (6) ◽  
pp. 803-816
Author(s):  
T. N. Alekseeva ◽  
N. V. Politova ◽  
N. V. Kozina

2005 ◽  
Vol 9 (1/2) ◽  
pp. 57-66 ◽  
Author(s):  
V. R. Shevchenko ◽  
Y. S. Dolotov ◽  
N. N. Filatov ◽  
T. N. Alexeeva ◽  
A. S. Filippov ◽  
...  

Abstract. The biogeochemistry of the river-sea interface was studied in the Kem' River (the largest river flowing to the White Sea from Karelian coast) estuary and adjacent area of the White Sea onboard the RV "Ekolog" in summer 2001, 2002 and 2003. The study area can be divided into 3 zones: I - the estuary itself, with water depth from 1 to 5m and low salinity in the surface layer (salinity is lower than 0.2psu in the Kem' River and varies from 15 to 20psu in outer part of this zone); II - the intermediate zone with depths from 5 to 10m and salinity at the surface from 16 to 22psu; III - the marine zone with depths from 10 to 29 m and salinity 21-24.5psu. Highest concentrations of the suspended particulate matter (SPM) were registered in the Kem' mouth (5-7mg/l). They sharply decreased to values <1mg/l towards the sea. At beginning of July 2001, particulate organic carbon (POC) concentration in the river mouth was 404µg/l and POC content in total SPM was 5.64%. In the marine part of the studied area the POC concentration varied from 132 to 274µg/l and the POC contents in suspended matter increased to 19-52.6%. These studies show, that the majority of riverborne suspended matter in the Kem' estuary deposits near the river mouth within the 20psu isohaline, where sedimentation of the suspended matter takes place. The role of fresh-water phytoplankton species decreases and the role of marine species increases from the river to sea and the percentage of green algae decreases and the role of diatoms increases. The organic carbon (Corg) to nitrogen (N) ratio (Corg/N) in both suspended matter and bottom sediments decreases from the river to the marine part of the mixing zone (from 8.5 to 6.1 in the suspended matter and from 14.6 to 7.5 in the bottom sediments), demonstrating that content of terrestrial-derived organic matter decreases and content of marine organic matter increases from the river mouth to the sea. The Kem' estuary exhibits a similar character of biogeochemial processes as in the large Arctic estuaries, but the scale of these processes (amount of river input of SPM, POC, area of estuaries) is different.


2021 ◽  
Vol 12 (3-2021) ◽  
pp. 45-53
Author(s):  
M.P. Venger ◽  

In the autumn period 2011, 2015 in the waters of the Barents Sea, the communities of viruses and bacteria were studied, their quantitative composition was determined, and the nature of their distribution was studied. It was shown that the distribution of both virio- and bacterioplankton had pronounced zoning presumably due to increased concentrations of organic matter in more productive coastal and Atlantic waters compared to the Arctic. In September 2011, the number of viruses varied from 0.6 to 46.7 million particles/ml, exceeding the abundance of bacteria by 5 times an average. The quantity of bacterioplankton varied within 0.3–2.9 million cells/ml, biomass – 4.1–35.1 mg C/m3, with a range of mean cell volumes of 0.030–0.115 μm3. In November–December 2015, the abundance of viruses was 0.3–6.4 million particles/ml and quantitatively exceeded their bacterial hosts by 18 times an average. The quantity and biomass of bacteria varied within 0.02–0.3 million cells/ml and 0.3–2.7 mg C/m3, with a range of mean cell volumes of 0.013–0.068 μm3. It was found that the level of development of virio- and bacterioplankton significantly decreased by the late autumn period.


Oceanology ◽  
2020 ◽  
Vol 60 (6) ◽  
pp. 831-839
Author(s):  
Yu. S. Glyaznetsova ◽  
I. A. Nemirovskaya

2021 ◽  
pp. 287-306
Author(s):  
A.Yu. Lein ◽  
◽  
A.S. Savvichev ◽  

Biogeochemical processes involving microorganisms play an important role in marine sedimentogenesis. The study of biogeochemical processes in the Barents Sea was carried out from 1997 with interruptions until 2019. Using a complex of geological-geochemical, microbiological, radioisotope and stable isotope methods, it was possible to obtain a quantitative estimate of the total abundance and biomass of microorganisms, rates of biogeochemical processes, methane content and organic matter suspended. In the course of work in four expeditions, it was found that in the surface (0–10 m) water column south of 74° N the magnitude of the total abundance and the biomass of microorganisms increased by 2019 by about 5 times compared to 1998. To the north, in colder waters, the total abundance and the biomass of organisms were lower than in the southern region of the sea. The methane concentration in the surface layer of the water column at the border with the atmosphere did not change much for 20 years (1976–1997) and increased noticeably from 1997 to 2017, from 3.3 to 15.8 nM. The increase in FFM, the biomass of organisms and the concentration of methane in the water column is associated with the melting of glaciers, with the release of organic matter of continental origin released from ice into the water. The results of the work indicate changes in the ecosystem of the Barents Sea.


2021 ◽  
pp. 899-943
Author(s):  
V.A. Shakhverdov ◽  
◽  
D.V. Ryabchuk ◽  
M.A. Spiridonov ◽  
V.A. Zhamoida ◽  
...  

A brief analysis of the history of environmental geological study of the Barents Sea is given. It shows that at the beginning of industrial development the geological environment was characterized by a low level of disturbance and pollution. On example of the Kola Bay, an assessment of the current environmental geological conditions of the fjords in the eastern part of the Barents Sea is given. Seismic-acoustic studies confirm the predominantly tectonic origin of the bay and the hazardous spread of gravitational rocks movement within the coastal slopes. The background geochemical characteristics of recent bottom sediments are quantified. It is shown that geochemical zoning of the bottom of the bay is a consequence of both natural and anthropogenic processes. According to the content of Cu, Zn, As, Cd, Pb, Hg and hexane-soluble petroleum products (PP) in the bottom sediments, the characteristics of various areas were obtained. It is shown that the distribution of PP and several other pollutants in the main components of aquatic and coastal geosystems is a leading element of the environmental monitoring system, quantitative assessment of anthropogenic impact and accumulated environmental damage. Active economic activity within the southern leg of the Kola Bay, as well as the naval bases, significantly affects the distribution of chemical elements. The data concerning distribution of chemical elements forms in bottom sediments are given that suggest a high probability of secondary pollution of the bottom water when the physicochemical conditions of sedimentation processes change. A comparative analysis showed that bottom sediments of the Kola Bay are characterized by the highest concentration of chemical elements in the North-West Region of the Russian Federation.


Oceanology ◽  
2011 ◽  
Vol 51 (6) ◽  
pp. 959-968 ◽  
Author(s):  
V. I. Peresypkin ◽  
A. V. Smurov ◽  
N. A. Shulga ◽  
E. S. Safonova ◽  
T. G. Smurova ◽  
...  

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