Influence of the Active Layer Thickness of Permafrost in Eastern Siberia on the River Discharge of Nutrients into the Arctic Ocean

Large rivers are important links between continents and oceans for material flows that have a global impact on marine biogeochemistry. Processes in the catchment areas of large rivers can affect the flow of solutes into the global ocean. The goal was to determine how the concentration of individual components of nutrients in the rivers of Eastern Siberia changes depending on the active layer thickness of the permafrost (ALT) and to elucidate whether the ALT is a factor that can control nutrient flux to the Arctic Ocean. The method of canonical correlation analysis was applied to the data on the concentration of nutrients in the 12 largest rivers of Eastern Siberia and the active layer thickness in their catchments. We found that the concentration of nutrients such as ammonium ion (NH4) and total phosphorus (Ptotal) in river waters is higher in catchments with a deeper active layer. The waters of the mountain rivers in the south of the region (the Chara and Vitim rivers) are the richest in nutrients. Arctic rivers such as the Indigirka and Anabar were low in nutrients. The permeability of soils also affects the discharge of nutrients into rivers with surface runoff. We conclude that in the future, in the context of global climatic changes and the projected deepening of the active layer throughout the permafrost zone of the Northern Hemisphere, an increase in the supply of nutrients to the Arctic Ocean is possible.

New results of a palynological study of the Lake Doroninskoe sediments (Eastern Siberia, Transbaikalia)

This article presents the results of the study of the bottom sediments of the meromictic Lake Doroninskoe. For the study, the method of spore-pollen analysis was used. The record showed that during the accumulation of 65 cm of the sediment layer in the Chita-Ingodinskaya depression, pine and larch predominated along the ridges, with steppe and meadow associations in the lower parts of the depression. According to regional correlations, the distribution of light-coniferous-taiga vegetation in Transbaikalia occurred as early as the Middle Holocene, and it did not undergo cardinal changes until modern times. According to these data, sediments may have accumulated during this time period.

Cladocera species (Crustacea, Branchiopoda) in the littoral zone of Lake Baikal: some representatives of Daphniidae families

Brief morphological descriptions of new Cladocera taxa (Daphniidae): Daphnia (Daphnia) turbinata Sars, 1903; Daphnia (Ctenodaphnia) sinensis Gu, Xu, Li, Dumont et Han 2013, found in Lake Baikal are presented. The representatives of these taxa inhabit the littoral zone of the lake and Olkhon Island. Daphnia (Ctenodaphnia) sinensis were encountered in the water bodies in the south of Eastern Siberia for the first time.

The Nitidula carnaria complex, with description of a new species from Central Asia, and a key to world species of the genus (Coleoptera: Nitidulidae)

The Nitidula carnaria complex is defined to comprise three Palaearctic species: the widely distributed Nitidula carnaria (Schaller, 1783), N. maculosa Fairmaire, 1866 occurring in the eremial of North Africa and the Middle East, and a newly described N. obenbergeri sp. nov. from northern China, Mongolia and neighbouring territories of Kazakhstan and Russia. First records are given for Nitidula carnaria from Georgia, Pakistan and Tajikistan; N. flavomaculata Rossi, 1790 from Azerbaijan, Kazakhstan and Kyrgyzstan; and for N. rufipes (Linnaeus, 1767) from Georgia, Kyrgyzstan, China (Shaanxi) and Russian Eastern Siberia. A lectotype of Nitidula latiplaga Solsky, 1876 is designated to fix its synonymy with N. flavomaculata Rossi, 1790 established by Jelínek & Audisio (2007). Habitus photographs of all species and an identification key are provided to facilitate identification of world Nitidula species. Finally, comments on the classification of four Neotropical taxa previously classified in the genus Nitidula are offered and the following changes are proposed: Mystrops bourgeoisi (Grouvelle, 1914), comb. nov., = M. gigas Kirejtshuk & Couturier, 2009, syn. nov.; and Catonura complanata (Germain, 1855), comb. nov., = Catonura ruficollis (Reitter, 1873), syn. nov., = Catonura rufithorax Reitter, 1883, syn. nov.

Effect of molybdenum on the structure and properties of electrodeposited alloys of iron and nickel

The article considered electrodeposited coatings made of iron- and nickel-based alloys doped with molybdenum. The studies carried out by optical and electron microscopy, X-ray structural analysis, as well as the determination of hardness and corrosion rate of the coatings under study allowed us to determine the laws of the influence of the structure on the properties of electrodeposited alloys immediately after obtaining, as well as after thermal treatment. Corrosion tests carried out both in the media of produced water of oil fields of Western and Eastern Siberia and in standard media allowed to determine the conditions for obtaining and thermal treatment of coatings, in which the effectiveness of protection with coatings is at maximum. Due to comparison with standard media, the influence of not only the pH of the medium but also the degree of its mineralization has been established. This article may be of interest to researchers studying the structure and properties of electrodeposited coatings, as well as to specialists in the field of corrosion protection and technologists of galvanic production.

Women’s Hairstyles and Head Ornamentation of the Yakuts in the 18th century

Mass Christianization of the peoples of Yakutia (Eastern Siberia) at the end of the 18th century led to the development of a demotic Christianity throughout the 19th century. There were new rules, according to which a woman was not permitted to appear in public with her head uncovered, and therefore the marking function of the hairstyles became obsolete. This could explain the absence of rituals and rules associated with women’s hair and hairstyles in the Yakut culture of the 19th–20th centuries. The aim of this study is to prove a hypothesis, according to which pendants of hair ornamentation duplicate braids, and studying the pendants of the headrest ‘nachel’nik’ allows recreation of women’s hairstyle that had been in use before the period of mass Christianization. The article is based on the analysis of written, material, and visual sources of the 18th–19th centuries. Information about the hairstyles and adornments of the Yakuts is contained within the records of travelers of the 18th–19th centuries. Among the ethnographic works on the peoples of Siberia, one can find drawings depicting maidens and women, where particular attention is given to their hair. These materials were correlated with the data of the archaeological excavations of Yakut female burials of the 18th century. The obtained results were compared with the materials from the 19th century — photographs of women in national costumes and jewelry from museum collections. According to the results of the study, it can be stated that there was a tradition of changing maiden’s hairstyle to woman’s hairstyle in the context of the wedding ritualism. New rules of conduct, social roles, especially regulations on the appearance of women, were formalized in the society in the 19th century with the mass Christianization of the peoples of Yakutia. There were new rules, according to which a woman was not permitted to appear in public with her head uncovered, and therefore the marking function of hairstyles became obsolete. This could explain the absence of rituals and rules associated with women’s hair and hairstyles in the Yakut culture of the 19th–20th centuries.