Organic Matter of the White Sea

Author(s):  
Alina I. Agatova ◽  
Natalia M. Lapina ◽  
Nadezhda I. Torgunova

Author(s):  
M. Yu. Tokarev ◽  
E. N. Poludetkina ◽  
A. V. Starovoytov ◽  
A. S. Pirogova ◽  
S. R. Korost ◽  
...  

The article discusses the results of complex geological, geophysical and geochemical studies of gas-saturated sediments within the Kandalaksha gulf, the White Sea. As a part of the marine study detailed seismoacoustic studies were conducted, resulting in the geometry of the seabed, the distribution of geological peculiarities of the sedimentary sequence, including the zones of focused unloading of hydrocarbon fluids. It is shown that assemblages of the «gas caps» are confined to the zones of maximal thickness of post-glacial sediments. The composition of the organic matter in the sediments and the gas phase has been studied in detail.



2014 ◽  
Vol 456 (1) ◽  
pp. 635-639 ◽  
Author(s):  
A. P. Lisitsyn ◽  
A. N. Novigatskii ◽  
V. P. Shevchenko ◽  
A. A. Klyuvitkin ◽  
M. D. Kravchishina ◽  
...  




2016 ◽  
Vol 119 ◽  
pp. 1-13 ◽  
Author(s):  
Alexey K. Pavlov ◽  
Colin A. Stedmon ◽  
Andrey V. Semushin ◽  
Tõnu Martma ◽  
Boris V. Ivanov ◽  
...  


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.





2011 ◽  
Vol 8 (1) ◽  
pp. 1309-1333
Author(s):  
S. Koukina ◽  
A. Vetrov ◽  
N. Belyaev

Abstract. The White Sea of Russian Arctic is characterized by extreme diversity of enclosed estuarine systems that are often sites of unique biota. The present study focuses on surface sediments from representative restricted exchange environments of the inner part of Kandalaksha Bay, adjacent to the Karelian shore of the White Sea. The TOC and n-alkanes distribution study revealed the major input of terrestrial organic matter into the sediments from higher plants and minor presence of autochthonous microbial sources. Metal (Fe, Mn, Cu, Zn, Cr and Pb) forms study showed that metals in sediments occur mainly in a biogeochemically stable mineral-incorporated form, which comprises up to 98% of total metal content, while labile (acid soluble) and organically bound (alkali soluble) forms make up to 3–11% and 2–12% of total metal content, respectively. Presumably, the major part of both acid soluble and alkali soluble forms is comprised of metals associated with easily soluble amorphous Fe-oxides and bound to sediment organic matter. According to sediment quality guidelines, all trace-metal contents were below the threshold levels. Among sites studied, the heightened contents of bioavailable metal forms are related to sediments enriched in organic matter and/or located within the sea-fresh water barrier zones. The elements studied may be arranged in the following decreasing sequence according to their potential bioavailability: Cu > Zn > Mn > Fe > Cr > Pb. The present study can serve as a basis for comprehensive environmental assessment of the region and objective anoxia prognosis in Arctic ecosystems, while the role of microbial community in element speciation in sediments needs special attention.



2015 ◽  
pp. 82 ◽  
Author(s):  
G. A. Safyanov ◽  
T. Yu. Repkina


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