Alexander N Novigatsky

Vertical Fluxes of Dispersed Sedimentary Matter, Absolute Masses of the Bottom Sediments, and Rates of Modern Sedimentation

A new approach using dispersed sedimentary matter of the water column captured by sediment traps in comparison with its consolidated form (surface layer of the bottom sediments) was applied to study sedimentation in the White Sea. The results of long-term investigations in a small sea of the Arctic Ocean served as a basis for revealing new regularities characteristic of the sedimentary process in the Subarctic and Arctic zones. The monthly, seasonal, and multiyear dynamics of the main components of dispersed sedimentary matter fluxes were analyzed by defining the marine sedimentation stage. It was shown that the biogenic constituents of the particle flux while its transition from the dispersed form to consolidated one decreased by an order of magnitude. The average values of the vertical flux were calculated including the total sedimentary flux and the contribution of main biogenic and lithogenic constituents per m2 of the bottom area of the White Sea.

Aeolian and Ice Transport of Matter (Including Pollutants) in the Arctic

The results of black carbon (BC) studies in the marine boundary layer over the White, Barents and Kara seas in August–September 2007, snow, ice and under-ice water were studied in the vicinity of the North Pole during the Pan-Arctic Ice Camp Expedition (PAICEX) In April 2008 and modeling of transport of air masses and pollution in the Russian Arctic are presented in this chapter. It is shown that aeolian and ice transport of matter plays an important role in the fate of black carbon, heavy metals and other contaminants in the Arctic.

Suspended Particulate Matter as a Main Source and Proxy of the Sedimentation Processes

The material for our study was collected in the White Sea during 22 interdisciplinary expeditions organized by the Shirshov Institute of Oceanology, Russian Academy of Sciences (IO RAS), in 2000–2014. The researches were carried out mostly in June–August; however we have some samples for autumn–winter and early spring seasons. Here, we report the concentration of suspended particulate matter (SPM), its composition and properties, as well as their changes due to natural zoning and local conditions. This paper discusses the features in the distribution of SPM concentration, grain-size, mineral, and major phase composition. As far as possible, we involved our own and other published data on hydrology, bottom morphology, and particulate and dissolved river runoff from the catchment area, abundance and composition of marine phyto- and bacterioplankton. This new knowledge has been used to describe particles dispersion system of the White Sea, which forms a giant reservoir of micro- and nanoparticles, using terms adopted in sedimentology and oceanography.

Occurrence Forms of Heavy Metals in the Bottom Sediments of the White Sea

The White Sea is an inner subarctic marine basin where sedimentation is known to be influenced by mostly terrigenous processes. In the catchment area of the White Sea, a lot of the mining, manufacture, and pulp and paper industry plants are located whose solid and liquid wastes contain heavy metals, including the toxic ones. Through the solid and dissolved river runoff, atmospheric fluxes, and coastal abrasion, heavy metals enter the seawater where they are involved in various biogeochemical processes before to be precipitated on the sea floor. Many studies of marine sedimentation concern total metal concentration; meanwhile, an assessment of contribution of different biogeochemical processes stays incomplete. In this chapter, we try to evaluate the partitioning among the different forms (speciation) of heavy metals that reflect principal processes of their accumulation in the modern bottom sediments of the White Sea. We study both the rock-forming (Al, Fe, Mn) and trace elements (Mo, Cr, Ni, Co, Cu, Pb, Cd, and As) by use of a modified method of selective sequential chemical leaching.

Mercury Distribution in Bottom Sediments of the White Sea and the Rivers of Its Basin

Interest in the study of subarctic areas of the Earth increases year by year, due to the accelerating pace of development of high latitudes and increasing anthropogenic pressure. In parallel with these processes, there is a growing need to study the behavior of substances of the first class of danger in the natural objects of the region. This article summarizes and analyzes data on Hg content in bottom sediments of the White Sea and rivers of its basin. The influence of the river flow of the Northern Dvina, Kyanda, and Kem Rivers on the formation of Hg concentrations in the bottom sediments of the White Sea, Dvinsky, and Onega bays has been studied.

Dispersed Sedimentary Matter of the Atmosphere

In this chapter we summarize results of aerosol studies over the White Sea and its coasts; we also analyze contribution of different anthropogenic constituents from European industrial cities and areas into studied aerosol composition. We estimated the degree of anthropogenic influence of these sources on the atmosphere and the terrestrial environment in this region. Data on airborne heavy metal accumulation in natural archives (snow cover, lichens, lake sediments) are generalized. The most significant source regions for some anthropogenic components depositing on the White Sea surface from atmosphere are revealed. Annual average (for 2000s) fluxes of anthropogenic Cu, Ni, Pb, Fe, Al, and black carbon incoming to the White Sea waters from various regions are evaluated. Studied element concentrations in the White Sea aerosols are generally on the level typical for other Arctic regions. In the Kandalaksha Bay, we traced the air mass arrival from metallurgical facilities of Murmansk Region. Elevated concentrations of heavy metals and black carbon were found in vicinity of industrial urban agglomeration of Arkhangelsk. For the first time, we assess contribution of Kostomuksha field (Karelia Republic) surface mining into Fe and Al fluxes (these elements are of both lithogenic and anthropogenic origin) on the White Sea surface which are comparable to contribution of the other source regions.

First Data on the Geochemical Speciation of Trace Metals in the Vertical Fluxes of Dispersed Sedimentary Matter in the White Sea

The contribution of different geochemical processes in the accumulation of metals in dispersed sedimentary matter collected by ADOO was estimated for the first time for the White Sea system. The contents of Al, Fe, Cr, Ni, Со, and Мо (from 60 to 90% of the total content) are mainly controlled by terrigenous processes. The group of geochemically mobile elements includes Mn, Cu, Pb, and Cd; the sum of their forms 1–3, which include the contribution of absorption−desorption and formation of authigenic hydroxides and organic compounds, accounts for, on average, from 52 to 83 Mn %. With increasing water depth, the fraction of the lithogenic form remains either constant or increases insignificantly. In contrast, Mn shows a sharp increase in geochemically mobile forms, heavy metals (Pb, Cu, Mo, Co, and Cd) of which are associated with.

Vertical Fluxes of Suspended Sedimentary Matter in Arctic Sedimentogenesis of Intracontinental Seas

Based on long-term studies of a small sea in the Arctic Ocean, new regularities in the sedimentary process under the conditions of Arctic sedimentogenesis were established. The quantitative transition of particulate sedimentary materials into the concentrated forms (bottom sediments) in the White Sea follows the linear dependence with a local maximum in the deep nepheloid layer. Marginal filters (Severnaya Dvina River, etc.), which are areas of ultrarapid sedimentation, were distinguished. The long-term data on the concentration of suspension and fluxes of particulate sedimentary material clearly indicate stable annual nepheloid layers, i.e., the distribution of particulate forms of sedimentary material (suspension) in the water column proceeds by new regularities, which may be distinguished ever more clearly.