The River–Sea Transition Zone (Marginal Filter) of the Northern Dvina River as an Effective Trap of Riverine Sedimentary Matter on Its Way to the Open Area of the White Sea

• Published in: Oceanology (Washington. 1965) 2022-04, Vol.62 (2), p.221-230
• Main Authors: Gordeev, V. V., Shevchenko, V. P., Novigatsky, A. N., Kochenkova, A. I., Starodymova, D. P., Lokhov, A. S., Belorukov, S. K., Yakovlev, A. E.
• Format: Article
• Language: English
• Subjects: Discharge; Earth and Environmental Science; Earth Sciences; Ecological research; Iron; Manganese; Marine Geology; Oceanography; Particulate matter; Rivers; Runoff; Sediments; Suspended particulate matter; Suspended sediments; Transition zone
• ISSN: 0001-4370; 1531-8508
• DOI: 10.1134/S0001437022020060

The article presents the results of generalizing the data of 20 years of research in the river–sea transition zone of the Northern Dvina River and White Sea (marginal filter zone), in which sedimentation and biogeochemical transformation of riverine sedimentary material lead to significant losses on its way to the open area of the sea. For the first time, based on a large amount of material, the average-weighted (in terms of runoff) quantities of the so-called “pure” discharge of suspended particulate matter and dissolved and suspended particulate Fe and Mn were obtained. These are discharges of these substances closest to reality with account for losses in the marginal filter zone depending on the season. It was determined that on average in a year from the total volumes transported by river waters to the boundary with the sea, only about 40% of suspended sediments, 50% of total iron, and almost 60% of total manganese reach its open areas. Precisely these volumes should be taken into account in computing the geochemical balance and in ecological research in the sea.