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The clay fractions of saprolites from granites, basalt, and schists in Egypt were subjected to mineralogical and geochemical investigations to examine the effect of source rock on the composition of the saprolites and the possibilities of these saprolites as a source of the nearby sedimentary kaolin deposits. The clay fractions of the studied saprolites show mineralogical and geochemical variations. Saprolites from the granites consist of kaolinite, while saprolites from the basalts are composed entirely of smectite. Schist-derived saprolites are composed of kaolinite in some cases and of a mixture of kaolinite, illite, and chlorite in the other. Saprolite from the basalts is characterized by relatively higher contents of TiO ₂ and Ni compared to saprolites from the granites. Saprolites from the granites have higher contents of Ba, Li, Pb, Sr, Th, Y, and Zr compared with those of the saprolites from the basalts and schists. Saprolites from different schists show variations in the distributions of many constituents, such as TiO ₂, Cr, Ni Ba, Y, and Zr. Although chondrite-normalized rare-earth element (REE) patterns are characterized by relative enrichments in light rare-earth elements (LREE) compared to heavy rare-earth elements (HREE) in all saprolites, granitic saprolites show negative Eu anomalies, while saprolites from the basalt have no Eu anomaly. The REE patterns of saprolites from the schists exhibit slight positive Ce anomalies and slight to moderate negative Eu anomalies. Weathering of saprolites from the basalt and metasediments is classified as bisiallitization type, while weathering of saprolites from the granite is allirization type. Saprolites from the schists vary from bisiallitization (Aswan and Abu Natash) to allirization (Khaboba) type. Saprolites from the Khaboba schist can be considered the possible source of the Carboniferous kaolin deposits in the Hasber and Khboba areas of Sinai, based on the similarity in the mineralogy and geochemistry of major, trace, and rare-earth elements between the saprolites and the deposits. On the other hand, Carboniferous sedimentary kaolin deposits in the Abu Natash area, as well as the Cretaceous kaolin deposits in all areas of Sinai, might have been derived from the nearby schist saprolites, based on the similarity in the mineralogy and geochemistry between the saprolites and the kaolin deposits. Granites from the Arabian-Nubian Shield (ANS) and East Sahara Craton (ESC) are the possible sources of the pisolitic and plastic kaolin deposits in the Kalabsha area (Aswan), as indicated from the similarity in the mineralogy and geochemistry of the granitic saprolites and the kaolin deposits.

A model of aerosol fallout fields from a series of sources has been developed. Аprobation of the model on data from field studies of snow dust pollution in the vicinity of thermal power station 2 and thermal power station 3 of Novosibirsk was carried out. The magnitude of the random RMS error is between 4–6 mg/l. The estimate of the total fallouts of dust from sources within a radius of 3 km from TPS 2 and TPS 3 in the winter season 2013–2014 was 61 and 10 tons, respectively.

A brief description of an original chemistry-transport model (CTM) based on technology of modeling and forecasting air pollutant concentrations is presented. Earlier results of evaluation of CHIMERE CTM outputs against measurements in the Moscow region demonstrated the adequacy of the simulation when WRF-ARW meteorological data were used. Initial CHIMERE CTM simulations based on the COSMO-Ru7 meteorological model outputs are presented and compared to the cases of standard and extreme conditions with air pollution monitoring data as well as to simulations based on the WRF-ARW calculations.

In the paper, results of many years studies of ozone concentration in three regions of Eastern Siberia (background, rural, and urban) are presented. Variations of different temporal scale ozone concentrations are considered: daily, seasonal and year–to–year, as well as the influence of natural and anthropogenic factors on these variations. It was received that ozone concentrations in every three regions have similar seasonal changes: maximum in spring and minimum in autumn. During all joint observation period, ozone concentrations in remote and rural regions had similar values, while in urban conditions the ozone concentration was 1.5–2 times lower. In addition to seasonal variations there are changes on synoptic scale and most clear daily variations caused by photo-chemical generation under the action of solar radiations. In rural site, short-time non periodical decrease in ozone concentrations was observed under the influence of regional air pollution. In background site during 18 years of observation, the maximal ozone concentrations were observed in 2003–2005, but from those years till recently the ozone concentrations have tendency to be lower.

Adaptive strategies of sporophytes of epilithic ferns were identified on the basis of research studies and literature data. Complex analysis of photosynthetic apparatus of the plants was carried out on different levels of its organization: frond, mesophyll cells and plastids. The sporophytes’ adaptation to the environment was also characterized on different levels of organization. Two morphofunctional (MFT) and two physiological-functional types (PFT) of ferns were isolated based on their adaptability to epilithic way of living. This division reflects the adaptive peculiarities of ferns in certain biomes.

Biological peculiarities of Matteuccia struthiopteris and Onoclea sensibilis (family Onocleaceae) corresponded to the dynamics of seasonal changes in temperate climates. It was established that the adaptive strategies of the studied species varied depending on the ecological and coenotic conditions. The range of these variations was wider for Matteuccia struthiopteris than Onoclea sensibilis.

Ontogenetic structure of eight Thymus mongolicus coenopopulations in Southern Siberia was studied and assessment of their state was done. It was established that the studied coenopopulations had left-hand, central and bimodal spectrum types. It was shown that the optimal state of coenopopulations was achieved in true petrophytic steppes. Organism optimum and population optimum did not coincide in the steppes on a moving substrate and under the influence of grazing.

Upon the study of geobotanical descriptions of steppe meadows and steppes of South Urals, ecological groups of plants were differentiated on the basis of their reaction to moisture factor. The analysis of the species activity index along moisture gradient allowed us to identify the plant species that are diagnostic for zonal types of steppes: meadow steppes (order Festucetalia valesiacae) and typical bunchgrass steppe (order Helictotricho-Stipetalia). Most plants had similar activity indexes both on West-Siberian plain and in South Ural. The regional differences were caused by geographic peculiarities of the habitats: petrophytic species are common in South Ural mountain landscapes, halophytic and sand species - on West-Siberian plain.

Meromictic lakes are interesting objects for paleolimnological study, and Lake Shira is one of such lakes. In May 2011 core samples were collected from the bottom of Lake Shira and the species composition of diatom algae, which serve as bioindicators of the state of the lake, were studied. Moreover, in the year 2012 seasonal water samples and material from sediment traps were collected and the species composition of diatoms in them was analyzed. The results of the analysis showed that the lake, as in previous years of research, was dominated by Cyclotella choctawhatcheeanа Prasad. Diatoms were found twice in the studied core, above the white carbonate layers and were absent in other layers. Down to the first white layer the species living in the lake at present time were observed, including the predominant Cyclotella choctawhatcheeana. This fact, presumably, proves the consistency of the species composition of diatoms and the overall stable condition of the lake since 1946 [Popova, 1946]. Down to the second white carbonate layer the dominant species were Aulcosira valida (Grunow) Krammer and Aulcosira italica (Grunow) Simonsen. Besides them, Nitzchia sigmodea (Nitzsch) W. Smith, Fragilaria construens var. venter (Ehrenberg) Grunow were also observed at these depths, dating approximately to 1655-1690. These are freshwater species that belong to the diatoms of arctic, alpine and temperate latitudes which develop in shallow waters under moderate temperature conditions. This fact suggests that Lake Shira was less salty in the middle and the end of the 17th century than today.

Cyanobacteria containing neurotoxic saxitoxin synthesis genes were found in the coastal zone of Lake Baiakl near the village Turka for the first time. Phylogenetic analysis showed that the sequences of saxitoxin synthesis genes belong to the genus Anаbaenа Bory. Saxitoxin concentration in the water according to ELISA was 1.93 ± 0.64 mg/l. Genetic and taxonomic composition of the bacterial community of the Central part (basin) of Lake Baikal was characterized using 16S rRNA gene pyrosequencing. It was established that phylum Cyanobacteria dominated in the composition of summer bacterioplankton in both littoral and pelagic zones of the lake, but higher species diversity was noted in the plankton of littoral zone.