New data on the elemental composition of the Severnaya Dvina River, the largest one in the White Sea region, are presented. The elemental composition of the river water in May, the period of the...

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.

Complex biogeochemical studies including the determination of isotopic composition of Corgin both suspended particulate matter and surface horizon (0–1 cm) of sediments (more than 260 determinations...

The speciation of Fe, Mn, Zn, Cu, Co, Ni, Cr, Pb, and Cd was studied in 52 samples of bottom sediments collected during Cruise 49 of the R/V Dmitrii Mendeleevin estuaries of the Ob and Yenisei...

Annual and long-term quantitative estimations of the vertical fluxes of sedimentary matter in the White Sea are the basis for direct calculations of the gain of chemical components and minerals and...

An analysis of suspended particulate matter (SPM) and phytoplankton distribution, composition and vertical particle fluxes in Russkaya Gavan’ Bay (Northern Island of the Novaya Zemlya), Bezymyannaya Bay (Southern Island of the Novaya Zemlya), Dolgaya Bay (northwestern part of the Vaigach Island) in comparison with the data from the Svalbard Archipelago is presented. Field studies were carried out by the authors during the 9th expedition of the RV “Professor Logachev” in September 1994, the 11th, 13th, and 14th expeditions of the RV “Akademik Sergey Vavilov” in September-October 1997 and August-September 1998. The data about Spitsbergen fjords are from literature. Our results show that, on the bays of the Barents Sea islands, most SPM stays in the bays (fjords) and only small part of it reaches the open sea. This is due to the hydrodynamic conditions in the bays, the large size of the particles, flocculation, and often to the morphological barriers in the relief at the bay entrances. It is important for ecological purposes to map out migration pathways of the SPM with pollutants from bays to the open sea. Results of our investigation indicate that the western bays of the Novaya Zemlya act as traps for SPM derived from glaciers and coastal abrasion.