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Dissolved organic matter (DOM) is an important component of aquatic environments; it plays a key role in the biogeochemical cycles of many chemical elements. Using excitation–emission matrix fluorescence spectroscopy, we examined the fluorescent fraction of DOM (FDOM) produced at the stationary phase of growth of five strains of microalgae sampled and isolated from the Ob and Yenisei gulfs. Based on the morphological and molecular descriptions, the strains were identified as diatoms (Asterionella formosa, Fragilaria cf. crotonensis, and Stephanodiscus hantzschii), green microalgae (Desmodesmus armatus), and yellow-green microalgae (Tribonema cf. minus). Three fluorescent components were validated in parallel factor analysis (PARAFAC): one of them was characterized by protein-like fluorescence (similar to peak T), two others, by humic-like fluorescence (peaks A and C). The portion of fluorescence intensity of humic compounds (peak A) to the total fluorescence intensity was the lowest (27 ± 5%) and showed little variation between species. Protein-like fluorescence was most intense (45 ± 16%), but along with humic-like fluorescence with emission maximum at 470 nm (28 ± 14%), varied considerably for different algae strains. The direct optical investigation of FDOM produced during the cultivation of the studied algae strains confirms the possibility of autochthonous production of humic-like FDOM in the Arctic shelf regions. [ABSTRACT FROM AUTHOR]

The structure of flora and fauna, which is a standard of the state and dynamics of the taiga forests in humid climatic facies of the Altai-Sayan mountain region, has been analyzed based on the example of the undisturbed mountain Siberian Pine taiga (Eastern Sayan mountains). The ecological–phytocenotic features and floristic and faunistic composition of the late succession stage are studied. The dominance of the green moss group of forest types is revealed across the topographic profiles. The forest stands have a complex age structure with the dominance of Pinus sibirica Du Tour. and are characterized by low productivity (quality classes IV–V prevail), high class of normality (from 0.5 to 1.0), and sufficient regeneration. A floristic, ecological–coenotic analysis of the herb–dwarf-shrub layer, the elements of undergrowth, and the moss cover indicates the dominance of humid taiga flora. The species of the taiga ecological–coenotic group (ECG) (Vaccinium myrtillus, Carex iljinii, Calamagrostis obtusata, Gymnocarpium dryopteris, Phegopteris connectilis, Oxalis acetosella, Aegopodium alpestre, Trientalis europaea, Linnaea borealis, Maianthemum bifolium, Stellaria bungeana, et al.), moss–bog ECG (Ledum palustre, Vaccinium uliginosum, Carex globularis et al.), and bor-taiga ECG (Vaccinium vitis-idaea, Pyrola rotundifolia, Lycopodium annotinum et al.) form the herb–dwarf-shrub layer in the prevailing forest types. Green mosses (Hylocomium splendens and Pleurozium schreberi with a mixture of Ptilium crista-castrensis and Rhytidiadelphus triquetrus) dominate in the moss layer. Polytrichum commune, P. strictum, Dicranum scoparium, D. polysetum, and Sphagnum sp. mosses are found in some sites. The increased role of higher spore plants characterizes the flora as well-preserved archaic features flora. The Siberian pine forest coenoflora consists of 224 species and belongs to the Cyperaceae type. In the structure of the geographical elements of the flora, the leading role belongs to the Palaearctic, European, and Siberian elements with an increased role of endemics. The species typical for the Siberia taiga complex compose the core of the fauna. The most diverse avifauna is represented by 102 species (Tarsiger cyanurus, Parus montanus, Parus ater, Luscinia calliope, Sitta europaea, Loxia curvirostra, Coccothraustes coccothraustes, Tetrastes bonasia, Phylloscopus proregulus, etc.). [ABSTRACT FROM AUTHOR]

The polymorphism of mtDNA was examined in populations of Old Believers ( n = 104) and Russians from Novosibirsk oblast ( n = 270). Most of the haplogroups identified belonged to West Eurasian lineages. The frequencies of these haplogroups constituted 96.6% in Russians from Novosibirsk and 93.2% in Old Believers from Tyumen oblast. The populations examined were characterized by a high mtDNA diversity level ( h = 0.98) compared to other population samples of Russians from Russia. Among the West Eurasian haplogroups, the most common (a frequency of more than 10%) were haplogroups H, U, J, and T, the proportion of which constituted 77.9% in Old Believers and 83.1% in Russians from Novosibirsk. The Mongoloid admixture in Russians (3.3%) and Old Believers (6.7%) was represented by haplogroups A, D, Z, and C, D, M*, respectively. Statistically significant differences ( P < 0.05) were revealed between the Old Believers examined and Bosnians, Czechs, Slovenes, and Russians from the cities of Nizhny Novgorod and Tula. The data obtained confirm the earlier hypothesized influence of the Finno-Ugric component on the East Slavic populations. [ABSTRACT FROM AUTHOR]