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Investment has a crucial impact on the economic development of territories. Traditionally, scholars studied many factors influencing investment (cost of interest rate, labor productivity, GDP growth, financial firm's performance). At present, the existing body of literature demonstrates the shift of factors related to territorial investment attractiveness. Besides economic dimension, the ecological and social matters take key stages (the ESG concept and the triple bottom line concept). Our study is aimed at exploring the relationship between investment at municipal level and ecological factors, considering regional specifics and settlement patterns in Russia. We applied hierarchical (multilevel) modeling with spatial effects to accomplish a twofold goal: to estimate what share of investment variance attributed to municipal and regional scale; to distinguish between spatial error at regional level and influence of average investment in neighboring municipalities at municipal level. Our findings show that 32% total investment variance accounted for regional scale; investment is positively associated with population, production per capita and the ratio of circulating water and sequentially used water to used fresh water. The results of this paper could be useful in developing policy for attracting investment at regional and municipal levels. Given vast national territories, a variety of different regions and heterogeneous settlement patterns, our study lays an initial ground of assessing environmental impact on investment in Russia. [ABSTRACT FROM AUTHOR]

The low production costs and useful properties of synthetic polymers have led to their ubiquitous use, from food packaging and household products to high-tech applications in medicine and electronics. Incomplete recycling of plastic materials results in an accumulation of plastic waste, which slowly degrades to produce tiny plastic particles, commonly known as "microplastics" (MPs). MPs can enter water bodies, but only recently the problem of MP pollution of sea and fresh waters has become clearly evident and received considerable attention. This paper critically reviews the accumulated data about the distribution of MPs in the freshwater ecosystems of Russia. The available data on MP abundance in the lakes and river systems of the Russian Federation are analyzed (including the large Lakes Baikal, Ladoga, Onego, Imandra and Teletskoe, and the Volga, Northern Dvina, Ob, and Yenisei Rivers within their tributaries) and compared with the data on freshwater MP contents in other countries. In Russia, the main sources of MP pollution for rivers and lakes are domestic wastewater, containing microfibers of synthetic textiles, fishing tackle, and plastic waste left on shores. Among the MPs detected in the surface waters and bottom sediments, polyethylene (PE), polypropylene (PP), and polyethylene terephthalate (PET) particles predominate. The most common types of MPs in the surface freshwaters are fibers and fragments, with fibers prevailing in the bottom sediments. The reported average MP concentrations in the waters range from 0.007 items/m3 at the mouth of the Northern Dvina River to 11,000 items/m3 in the Altai lakes. However, the estimates obtained in different studies must be compared with great precaution because of significant differences in the methods used for MP quantification. The approaches to further improve the relevance of research into MP pollution of fresh waters are suggested. [ABSTRACT FROM AUTHOR]

Heterotrophic protists Rotosphaerida, Thaumatomonadida, and centrohelid heliozoans are among the less studied silicified protists in terms of their biogeography and ecology. These organisms inhabit fresh and brackish water, and leave behind siliceous structural elements after death that are species‐specific and amenable to electron microscopic analysis. This paper is the first to present data on species richness and taxonomic structure of silica‐scaled heterotrophic protists—rotosphaerids, colorless free‐living thaumatomonad flagellates and centrohelid heliozoans—in the large continuous water system of Siberia connecting Lake Baikal to the Kara Sea. In the study area, electron microscopy revealed 21 centrohelid heliozoan species from the genera Raphidiophrys (1), Acanthocystis (7), Choanocystis (3), Raineriophrys (2), Raphidocystis (6), and Pterocystis (2), seven rotosphaerid species from the genera Pinaciophora (3), Turriplaca (2), Rabdiophrys (1), and Pompholyxophrys (1), and one thaumatomonad flagellate species Thaumatomastix. Two species of rotosphaerids, Rabdiophrys cf. anulifera and Pinaciophora tridentata, and two species of centrohelid heliozoans, Acanthocystis cf. tubata, and A. cf. cornuta, were found in the waters of Russia for the first time. The most widespread species in fresh water from Lake Baikal to the Lower Yenissei River were Pinaciophora fluviatilis and Raineriophrys cf. fortesca. These species disappeared from the protist assemblages of the Yenissei gulf of the Kara Sea due to higher salinity, with only three species, Acanthocystis cf. mylnikovi (at 3.12‰ salinity) and A. pectinata and Raphidocystis sp. 2 (at 8‰ salinity), found in the area. The sensitivity of silica‐scaled heterotrophic protists to changes in habitat parameters suggests that these microeukaryotes could be new indicator organisms. [ABSTRACT FROM AUTHOR]

Last decades, cyanobacterial blooms have been commonly reported in Russia. Among the boom-forming species, potential toxin producers have been identified. The aim of this paper was to study the presence of neurotoxic compounds - saxitoxins and anatoxin-a - in water bodies from different regions of Russia. We also made attempts to identify the neurotoxin-producing genera. The good convergence of the results obtained by light microscopy, PCR and LC-MS/MS analyses indicated the presence of active neurotoxin producing species in all investigated water bodies. Saxitoxin was detected in phytoplankton from 4 water bodies in Central European Russia and West Siberia, including lake and reservoirs used as a source for potable water. The water bodies differed with the respect of saxitoxin producers which belonged to Aphanizomenon and/or Dolichospermum genera. For the first time, we obtained quantitative data on the intracellular saxitoxin concentration in Russian freshwaters using LC-MS/MS. Anatoxin-a was detected only in lakes of Northwestern Russia. In the eutrophic shallow Lower Suzdal Lake, Aphanizomenon was the stated anatoxin-a-producing genus. In the large shallow artificial hypertrophic Sestroretskij Razliv Lake, it was very likely that both dominant species - Aphanizomenon flos-aquae and Dolichospermum planctonicum - were anatoxin-a producers., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Some scientists believe today that problems related to phosphorus entry into fresh-water bodies may be more important for setting the planetary boundary. Excessive entry of biogenic elements (especially phosphorus) into water bodies and water streams causes their eutrophication. This process may cause a decrease in the light transmittance of surface water layers and other consequences for ecosystem and humans. In this paper the results of model application for the estimation of the phosphorus content in fresh waters of the Russian Federation regions are presented. The method for the estimation of the phosphorus amount in fresh water was developed on the basis of the dynamic model. Phosphorus loading is most characteristic of regions that have developed types of agriculture which cause increases the rate of mineral phosphorus entry into erodible soil. [ABSTRACT FROM AUTHOR]

The paper gives data on the use of techniques to detect and register Salmonella in the water objects, by applying a new liquid nutrient medium. Experimental and field studies have shown its advantage over the accumulation media widely used in practical healthcare. It has been ascertained that the nutrient medium not only accumulates biomass, but also provides the restoration of the biological properties of uncultivated Salmonella species. The use of the nutrient medium at practical laboratories makes it possible to unify guidelines for the examination of water objects with varying degrees of biological pollution and to obtain the comparable results of analyses.

The paper gives the data characterizing the specific features of formation of an anthropogenic load on water bodies in north regions; sanitary and hygienic criteria for estimating the biological contamination; and the factors that increase the biological productivity of the algal flora; a classification of eutrophic waters is also proposed.

The paper estimates the epidemic value of indicators for microbial contamination of waters from their main supply sources (waters from the Tsimlyansk Reservoir and the Nizhni Don River and drinking waters from the towns of Azov and Tsimlyansk) in the Rostov Region. The Tsimlyansk Reservoir water met the SanPiN 2.1.5.980-00 requirements for the normalizable indices of total coliform bacteria (TCB) and thermotolerant coliform bacteria (TtCB) in 54% of the samples; glucose-positive coliform bacteria (GPCB) and Salmonella were isolated in 100 and 60%, respectively. The Azov drinking water that met the SanPiN 2.1.4.1074-01 requirements for TCB and TtCB) was found to contain GPCB, Klebsiella, and Pseudomonas aeruginosa in 5.7, 4.8, and 3% of the samples, respectively Direct detection of pathogenic and potentially pathogenic microorganisms and the integral GPCB index are of the greatest prognostic value in assessing a microbial risk for waterborne enteric infections.

The most frequent causative agents of cercarial dermatitis in Europe are the avian schistosomes of the genus Trichobilharzia . They preferably parasitize birds of the Anatidae. Trichobilharzia spp. schistosomes are also able to penetrate mammalian skin, posing a health risk to mammals, including humans. Currently several loci from nuclear and mitochondrial genomes are determined for European species of Trichobilharzia . Among them there is 1 genome sequence, ToSau3A, which is suitable for detection of Trichobilharzia spp. infection in aquatic systems. In the present paper, we used a PCR assay to obtain novel genome sequences from cercariae isolates of 3 European bird schistosome species ( Trichobilharzia franki , Trichobilharzia szidati , and Trichobilharzia regenti ) collected from freshwater ponds in Belorussia and Russia. We applied RAPD-fingerprinting using 1 random primer to differentiate 3 trichobilharzian species and subsequently cloned and sequenced putative species-specific RAPD fragments. One of them (410 bp in length), which was obtained for T. franki , revealed 64% homology with the repeat region of Schistosoma mansoni (GenBank FN357352) and turned out to be suitable for designing a specific primer pair (TR98F and TR98R) to detect 7 novel DNA sequences in the genome of 3 European Trichobilharzia species. The newly designed primer pair was found to be potentially suitable for PCR-based detection of trichobilharzian infection in snails. PCR primers TR98F and TR98R amplified only the DNA isolated from cercariae and sporocysts of 3 trichobilharzian species, but neither the DNA of 3 other digenean species ( Bilharziella polonica , Apatemon sp., and Diplostomum sp.) nor the DNA of uninfected host snails ( Lymnaea stagnalis , Radix auricularia , and Radix ovata ).

Summary. The paper provides comparative characteristics of water quality in the assessment of a risk for intestinal infections in drinking water use. It has shown that of the greatest predictive value is direct detection of potentially pathogenic microorganisms, as well as the integral indicator determined by glucose fermentation, such as glucose-positive coliform bacteria. Estimation of the per cent of nonstandard samples of water before its entering the distribution network and in the latter, including glucose-positive Escherichia coli GPEC, is recommended. The samples containing GPEC in a quantity of more than 2 CFU/100 ml should be singly taken into account.

Thorough data on 67 coccidian species of the genera Eimeria, Goussia, and Isospora parasitizing fishes in the continental waters of Russia are given. Authors, year of description, synonyms, morphofunctional organization, and list of the hosts are reported for each species. The paper is supplied with figures of the exogenic stages of coccidia (oocysts).

The paper summarizes the results from radioecological studies of a number of water basins located on the East-Urals Radioactive Trace (EURT), as exemplified by the lakes Large Ighish, Small Ighish and Shablish which are included in the medium-distance and remote zone of the EURT. The lake Misyash which is situated in the opposite direction from the release vector and has been only contaminated due to global fallouts has been used as a control water basin. The current species composition of the high aquatic plants and species-specific concentration of 90Sr and 137Cs in them was studied, also, the radionuclide accumulation and discrimination coefficients were estimated.

The paper presents data on the current radioecological situation at Lake Maly Igish located on the axial part of the East-Urals radioactive trace formed after the 1957 accident at the Mayak PA. The chemical composition of the water and bottom deposits, as well as the distribution of 90Sr, 137Cs, and of the microelements in the main components of the water reservoir were studied. The current species composition of higher aquatic plants and of the species-specific concentration of 90Sr and of 137Cs was identified.

An obligately anaerobic, hyperthermophilic, organoheterotrophic archaeon, strain Z-1312(T), was isolated from a freshwater hot spring of the Uzon caldera (Kamchatka Peninsula, Russia). The cells were regular cocci, 1-4 microm in diameter, with one long flagellum. The cell envelope was composed of a globular layer attached to the cytoplasmic membrane. The temperature range for growth was 63-89 degrees C, with an optimum between 80 and 82 degrees C. The pH range for growth at 80 degrees C was 4.8-6.8, with an optimum at pH 6.0. Strain Z-1312(T) grew by hydrolysis and/or fermentation of a wide range of polymeric and monomeric substrates, including agarose, amygdalin, arabinose, arbutin, casein hydrolysate, cellulose (filter paper, microcrystalline cellulose, carboxymethyl cellulose), dextran, dulcitol, fructose, lactose, laminarin, lichenan, maltose, pectin, peptone, ribose, starch and sucrose. No growth was detected on glucose, xylose, mannitol or sorbitol. Growth products when sucrose or starch were used as the substrate were acetate, H(2) and CO(2). Elemental sulfur, thiosulfate and nitrate added as potential electron acceptors for anaerobic respiration did not stimulate growth when tested with starch as the substrate. H(2) at 100 % in the gas phase did not inhibit growth on starch or peptone. The G+C content of the DNA was 42.5 mol%. 16S rRNA gene sequence analysis placed the isolated strain Z-1312(T) as a member of the genus Desulfurococcus, where it represented a novel species, for which the name Desulfurococcus fermentans sp. nov. (type strain Z-1312(T) = DSM 16532 (T) = VKM V-2316(T)) is proposed.

Data on the current radioecological status of lake Bolshoi Igish in the Middle Ural are presented in the paper. The lake is situated on the central axis of the East-Urals radioactive trace which was formed as a result of the 1957 nuclear accident at the Mayak Production Association. The distribution of 90Sr and 137Cs in the major components of the water basin is shown. Seasonal dynamics of the specific activity of radionuclides in water and in bottom deposits has been investigated. The current community of the higher water plant species has been studied. The paper discusses the concentration of 90Sr and 137Cs in the macrophyts of lake Bolshoi Igish depending on their species.

The paper presents data on the rates of Lamblia cyst dissemination of surface water sources in foreign countries, the Russian Federation, Moscow, and the Moscow Region. It shows a role of drinking water in the spread of intestinal parasitic diseases. In accordance with parasitological parameters, specific data on improvement of methodological control of water quality are presented. The dosages of ultraviolet radiation are given in relation to water decontamination of parasitic disease germs.

The paper shows it necessary to exercise control over the quality of natural, waste, and portable water in terms of parasitological indices. The standard techniques of sampling and sanitary and parasitological studies of water, which allow water quality control to be effectively exercised in accordance with the current sanitary regulations, are considered.

The paper provides data on the invasion of Acipenser ruthenus (sterlet) in the North Dvina River by Polypodium hydriforme (Cnidaria). Prevalence and intensity of invasion proved to be similar for two fishing sites. Prevalence of invasion exceeded 88%, thus being exceptionally high for P. hydriforme. Intensity of invasion was from 1 to 436 eggs per female. A verage percentage of infected eggs was about 1%.

The paper deals with the studies of the efficiency of four small-sized plants for biological purification of household waste waters (WW), which were conducted by using a complex of sanitary criteria, such as organoleptic, sanitary-and-chemical and sanitary-and-microbiological parameters of water quality of water objects, such as purified WW reservoirs, and presents a comparative assessment of their efficiency. The used methodological scheme is shown to provide an objective evaluation of the sanitary efficiency of the equipment under test with an compulsory set of regulated and additional integral parameters that should be regarded in combination. It is recommended that preference should be given to WW purification technologies that are effective in removing the environmentally hazardous chemical substances used in household chemistry.

Abstract: Using participatory scenario-making has become increasingly common in environmental assessments that aim for policy impact. In this development, ‘social work’ – i.e., construction and usage of the scenarios – has received only a little analytical interest. In this paper, we contribute to filling this gap of knowledge by focusing on the construction of scenarios and asking what kind of policy relevant knowledge these kinds of participatory experiments can provide for the resolution of environmental problems. We draw on experiences gained from a SCENES scenario-making experiment wherein a comprehensive set of scenarios for the future management of European freshwater resources was developed in a highly participatory manner. The SCENES work aimed at providing policy-relevant knowledge for implementation of the European Water Framework Directive (WFD). In this paper, we analyse and compare how issues were formulated and articulated as public concerns during the scenario-making process for the Narew River Basin, in Poland, and Lake Peipsi, in Estonia. The empirical narratives highlight that scenario-making assisted in articulation of the critical entanglements between the water systems and regional socio economic development. The implementation of the WFD has been largely unable to address these issues. In this sense, SCENES engaged in the articulation of public concerns. In SCENES there was, however, a latent tension in seeing scenario-making as either informing or forming social choices for water management. The epistemic principle of informing guided many of the methodological choices made during SCENES, whilst attempts aimed at issue formation characterised the panellists’ way of developing scenarios. Resolving this tension is decisive for the future governance of European freshwater resources. We close the paper by discussing why. [Copyright &y& Elsevier]

The paper provides evidence that Cryptosporidium oocysts should be necessarily included as an index of the epidemic safety of drinking water in our country. This is evidenced by: the wide spread of cryptosporidiosis among animals and human beings; that of the pathogen of this disease in the environment; large-scale outbreaks of cryptosporidiosis in the world's population; no sanitary and parasitological drinking water monitoring in our country; the use of this parasitological index to evaluate drinking water quality in some countries (USA, UK, Ukraine, etc.).

The paper provides sanitary and toxicological water characteristics in the city of Yaroslavl on the Volga River in 1993-1996. The water was shown to contain high levels of petroleum products, COD, and toxic substances. The water concentrations of phenol were no greater than the acceptable values. Those of metals, pesticides, and detergents did not exceed the sanitary standards.

This note is based on interviews conducted with people concerned with the Baikal Fund, a local group campaigning for the protection of Lake Baikal in Siberia. Baikal is the most voluminous body of fresh-water in the world (23,000 cu.km.), and home to many unique forms of plant and animal life. Since the mid-1960s it has been the focus of a complex struggle between Soviet ministries (one of them reponsible for the proposal in the 1960s to construct two wood-processing factories in the vicinity of the lake), local limnologists studying fresh waters and their ecology, and a substantial body of public opinion. This struggle has generated a considerable literature in the West, some of the more prominent items of which are included in the references following the note. For a concise statement of the issues involved, presented in the context of an overall treatment of Soviet environmental policies and problems, the reader may refer to Philip R. Pryde, Environmental Management in the Soviet Union (Cambridge: Cambridge University Press, 1991), Chapter 5. [ABSTRACT FROM AUTHOR]

Molecular data were used to revise the diversity of the genus Cryptomonas in Russia, using samples collected across nine geographic regions within Russia from 2015–2019. Several molecular markers were used: nuclear SSU, LSU and ITS2 rDNA, and plastid psbA. In total, 24 species of the genus Cryptomonas were identified in the country's fresh waters based on 122 different strains. Six new species were identified and are described here (Cryptomonas matvienkoae sp. nov., C. furtiva sp. nov., C. paludosa sp. nov., C. ursina sp. nov., C. kisselevii sp. nov. and C. meshchorana sp. nov.), and three taxa are emended (Cryptomonas skujae, C. platyuris and C. obovata). These new and emended species group in clades with the previously described species or represent new lineages on the phylogenetic tree. Seven morphospecies, previously reported in Russia, are confirmed by molecular methods, and two unidentified taxa are also reported. HIGHLIGHTS Molecular investigations of the genus Cryptomonas in Russia revealed 24 species. Descriptions of three species were emended. Six species new to science were described. [ABSTRACT FROM AUTHOR]

The paper presents the results of a study of groundwater saturation degree in relation to the minerals of kimberlite breccia based on the physicochemical modeling of equilibrium in the brine-kimberlite system. Highly concentrated Ca Cl brines with salinity of up to 400 g/L were discovered through boreholes drilled in the deep horizons of the diamond-bearing deposit of the Udachnaya pipe (Western Yakutia, Russia). The sampling depth of kimberlite was 1034–1145 m and the depth of the water sample from the ore body was 869 m. The pipe rocks are kimberlite breccias that consist of minerals such as serpentine, calcite, chlorite, mica, and quartz. The simulation results, using HydroGeo software, showed that the brines in the deep horizons of the ore body of the Udachnaya pipe remain unsaturated in relation to almost all groups of kimberlite-forming minerals (carbonate, sulfate, chloride, clay, and aluminosilicate) at any temperature and pressure in the reservoir. The nature and degree of equilibrium in the brine-kimberlite system, formed in the course of their long geochemical evolution, were influenced by the processes of both dissolution-precipitation of the chemical components of the system and the dilution of ground brines with low-salinity or fresh waters. • Deep seated highly concentrated brines contact with kimberlites of Udachnaya pipe. • Ca Cl brines are unsaturated to kimberlite-forming minerals at any PT-conditions. • Non-equilibrium state relates to with the evolution of the brine-kimberlite system. [ABSTRACT FROM AUTHOR]

Toyemia Minich, 1990, is a widespread member of late Permian freshwater fossil assemblages of European Russia. The scales and lepidotrichia hemisegments of this taxon show general resemblance to the palaeoniscoid-type ʻganoidʼ scales of most Palaeozoic actinopterygians, but differ from these in some morphological features. Architecture of the vascular system is more complex: part of the canals (the wider ones) are located within the bone layer, constituting a complicated three-dimensional pattern, while the thinner canals usually lie on the border of the bone and the dentine layers (with the canal lumen usually surrounded by dentine but positioned in the basalmost part of the odontode), forming a regular network, especially in the posterior and ventral part of a scale. Whereas in most basal actinopterygians, vascular canals only occur underneath the sculptural ridges of the free field, scales of Toyemia possess wide, sinuous canals underneath the depressed field, opening to its surface in large pores. These and further features of the squamation (vascular canals cased in concentric layers of bone reminiscent of osteons and surrounded by numerous osteocyte lacunae; the presence of true secondary osteons; the shape of articulating elements and the general scale outline; the ornamentation of the free field, mainly consisting of concentric rolls; etc.) are similar to representatives of the Triassic order Scanilepiformes, especially to the family Evenkiidae, suggesting that Toyemia should be placed within this family. An enigmatic 'circular structure' of interwoven collagen fibers, first observed in Toyemia scales, is reminiscent of polypterid elasmodine. In several aspects, scales of Toyemia appear to represent the ancestral condition of the polypteroid scale. [ABSTRACT FROM AUTHOR]

Horseshoe crabs are extant marine euchelicerates that have a fossil record extending well into the Palaeozoic. Extreme xiphosurid morphologies arose during this evolutionary history. These forms often reflected the occupation of freshwater or marginal conditions. This is particularly the case for Austrolimulidae--a xiphosurid family that has recently been subject to thorough taxonomic examination. Expanding the austrolimulid record, we present new material from the Olenekian-aged Petropavlovka Formation in European Russia and assign this material to Attenborolimulus superspinosus gen. et sp. nov. A geometric morphometric analysis of 23 horseshoe crab genera illustrates that the new taxon is distinct from limulid and paleolimulid morphologies, supporting the assignment within Austrolimulidae. In considering Triassic austrolimulids, we suggest that the hypertrophy or reduction in exoskeletal sections illustrate how species within the family evolved as opportunistic taxa after the end-Permian extinction. [ABSTRACT FROM AUTHOR]

Results from decades-long authors' research on the natural ecosystems of several freshwater water bodies in the Central Region of the European part of Russia were summarized. In particular, the process of formation of dissolved organic matter (DOM) after death of phytoplankton cells was studied in experiments with natural water samples. After the death of phytoplankton cells the destruction of dead cells and release of some part of the cell contents into the aquatic environment as dissolved organic matter occurred within one week. In the first three days bacteria consumed ~50% of the DOM thus released, and subsequently up to 30‒35%. Experiments with plankton of natural water samples collected from June through September showed that ~70% of the organic matter secreted by living phytoplankton cells and ~40% of that released into the water after the death of phytoplankton cells was consumed by bacterioplankton. Also studied were quite a number of other aspects of interactions between DOM, phytoplankton, bacteria, and detritus. For the first time, detailed quantitative data on the detrital particles in the aquatic freshwater ecosystems and some data on the formation and oxidative biodegradation of DOM by plankton, as well as many other quantitative data were obtained. [ABSTRACT FROM AUTHOR]

Water contaminated with liable to be pathogenic mycelial fungi in tributaries may cause health hazards to animals, birds and humans. The presence of mold fungi in water can be dangerous due to daily contact with water at several points of exposure, such as drinking, showering and swimming in lakes during the summer season. Affections of fungi of the genus Aspergillus, Penicillium, Fusarium, Mucor, Rhizopus cause allergies, opportunistic infections, mycosis and intoxication in living beings. Fresh water bodies, lakes, ponds are a black box for fungal ecology. Microbial organisms of bacteria, viruses, mycelial fungi directly affect agricultural land as well as social forestry. The article presents the results of mycological analysis of fresh water bodies in the territory of the park "Mari Chaudra". We allocated fungi of a sort Trichoderma - 46%, Aspergillus - 27%, Fusarium - 13%, Penicillium - 10%, Mucor - 2%, yeast fungi Candida - 1% and Rodoturulla - 1%. Practical results showed the relationship of natural balance of micelian fungi, ecotoxicants with acid-alkaline balance and aquatic vegetation in water bodies. [ABSTRACT FROM AUTHOR]

The Kara and Laptev seas receive about one half of total freshwater runoff to the Arctic Ocean from the Ob, Yenisei, and Lena rivers. Discharges of these large rivers form freshened surface water masses over wide areas in these seas. These water masses, i.e., the Ob-Yenisei and Lena river plumes, generate an eastward buoyancy boundary current that accounts for the large-scale zonal freshwater transport along the Siberian part in the Arctic Ocean. In this study we investigate spreading of the Ob-Yenisei plume from the Kara Sea to the Laptev Sea through the Vilkitsky Strait and of the Lena plume from the Laptev Sea to the East-Siberian Sea through the Laptev and Sannikov straits during ice-free season. Large horizontal density gradient between freshened plume water and salty ambient sea water is the main driver of these processes, however, their intensity strongly depends on local wind forcing. The Ob-Yenisei plume is spreading to the Laptev Sea in a narrow alongshore current which is induced by strong and long-term southwesterly winds. Under other wind forcing the plume does not reach the Vilkitsky Strait. The Lena plume is almost constantly spreading to the East-Siberian Sea as a large-scale surface water mass which intensity is governed by eastward Ekman transport and is prone to large synoptic variability. [ABSTRACT FROM AUTHOR]

There are two main types of mineral waters used in the Staraya Russa spa: (1) the saline waters of the Middle and Upper Devonian Arukjula–Shventoy aquifer with isotopic composition of δ18O from − 10.7 to − 11.3‰ and δ2H from − 81.3 to − 85‰ and (2) the brackish waters of the Upper Devonian Sargayev–Daugava aquifer with isotopic composition of δ18O from − 12.5 to − 12.9‰ and δ2H from − 93.0 to − 94.1‰. Hydrogeological conditions within the spa and its vicinity are complex due to hydraulic contacts between artesian aquifers and the saline waters ascension into shallower fresh water aquifers. The studies revealed that saline waters of the Arukjula–Shventoy aquifer are mixtures of approximately equal fractions (0.5) of snow melt water of δ18O around − 21.7‰ and seawater-like end-member of isotopic composition similar to modern ocean water (i.e. VSMOW). The brackish waters of the Sargayev–Daugava aquifer are result of mixing between infiltration waters and saline waters ascending from deeper Arukjula–Shventoy aquifer, the fraction of saline water may reach from around 0.2 to 0.4. The sulfur (δ34S) and oxygen (δ18O) isotopic composition of sulfates dissolved in mineral waters indicate that their source is connected with marine sulfates. The ionic ratios of major chemical compounds corroborate the presence of the connate seawater-like component in the hydrogeological system, which is responsible for the observed chemical composition of mineral waters extracted in Staraya Russa spa. [ABSTRACT FROM AUTHOR]

Summary: Sivash Bay is the largest hypersaline lagoon in the world. In 1963-1975 the North Crimean Canal was constructed, with water from the River Dnieper and discharge of drainage water collected from agricultural lands into Sivash Bay. Salinity in Sivash Bay began to drop, resulting in a new brackish water ecosystem. The political decision to stop supplying water from the River Dnieper to the Canal was made in 2014, and the discharge of fresh water into the lagoon ended, resulting in an increase in salinity up to 60-75 g l−1. This study showed that the abundance of meiobenthos increased, with Nematoda dominating. The composition of nematode species in the lagoon has not previously been studied. Using samples from 1979, 2013 and 2015, 50 nematode species and forms were identified in 1979, 32 in 2013 and 21 in 2015. The species composition of nematodes at different periods was significantly different. The average abundance of nematodes was 134 198 ind. m−2 in 2013 and 606 660 ind. m−2 in 2015. [ABSTRACT FROM AUTHOR]

Water chemistry in deep freshwater lakes and springs, situated in boggy areas and giving rise to the majority of the Russian rivers, is considered. Those lakes and springs can serve as an important reserve of fresh drinking water. [ABSTRACT FROM AUTHOR]

The results of studies aimed to assess the information significance of the coefficients of bottom accumulation of hydrophobic organic substances and heavy metals as indicators of pollution of freshwater bodies are presented. It is shown that the same value of the coefficient of bottom accumulation may correspond to different situations in water bodies. Methods for the interpretation of data on the state of water bodies based on the coefficient of bottom accumulation and its components are proposed to reliably determine the level and character of pollution. Chronic pollution of a number of freshwater bodies of the Russian Federation is assessed by data on the accumulation of pesticides, oil products, polycyclic aromatic hydrocarbons, and heavy metals in bottom deposits. [ABSTRACT FROM AUTHOR]

The principles of hydrogeological zoning of the territory of Russia by the conditions of formation and the distribution of the natural resources of fresh groundwater are discussed. The delineation of the first- and second-order regions is shown to be based on the principles of general hydrogeologic zoning, whereas that of the third and fourth orders is shown to be based on the principles of special hydrogeologic zoning, which can account for the specific structural features of the hydrogeologic section of the zone of intense water exchange, different types of water-bearing rocks, the structure of the unsaturated zone, and, in a number of cases, the climatic and landscape features of the area. [ABSTRACT FROM AUTHOR]