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This paper presents the quality requirements for the treatment of diesel fuel to reduce environmental pollution. The total operating costs of the conventional diesel treatment system are considered. The results of the dependence of the components of the costs and the total costs of cleaning diesel fuel on the quality of preliminary cleaning are summarized. A plan has been developed to minimize the cost of pre-treatment of diesel fuel.

Soil microbiome plays a significant role in the development of the soil profile and the implementation of key soil biochemical processes. Observed Arctic warming creates significant environmental risks, since permafrost soils contain a huge amount of organic matter, which is in potential risk to be released in the form of greenhouse gases. This work is aimed to investigate the microbiomes in soils of mature tundra and anthropogenically affected areas of the Yamal region using a high-throughput sequencing approach. The taxonomic analysis of the soil microbiomes revealed 33 bacterial and archaeal phyla, among which the dominant were Proteobacteria, Acidobacteria, Actinobacteria, Bacteroides, Chloroflexi, Cyanobacteria, Firmicutes, Gematimonadetes, Patescibacteria, Plantomycetes, Thaumarchaeota, Verrucomicrobia, and WPS-2. The analysis of alpha and beta diversities revealed that undisturbed soil is completely different from anthropogenically affected ones in terms of microorganism biodiversity. Soils of the urban zone of Salekhard were found to be different with regard to the number of operational taxonomic units and beta diversity. Herein the microbiome in the upper and lower layers of soil developed under strong technogenic influence (M19) was unequal both in quality and in quantity. At the same time, soils developed in the recreational zone of Salekhard showed less differentiation profile of microbiome (former crop field and former vegetable garden soils). Microbial communities in the mature tundra soil showed less differentiated microbiome composition.

Precision agriculture requires a wide sampling procedure to determine the spatial variability of soil properties for adequate assessment of soil state and appropriate recommendations. Electrical geophysical methods (i.e. vertical electrical resistivity sounding) allow performing rapid measurement of soil electrical properties directly from the soil surface to any depth without any mechanical disturbance of soil cover. Soil electrical properties are linked with many soil properties and could improve the quality and spatial coverage of soil surveys. The results obtained in our study using vertical electrical resistivity sounding confirmed the hypothesis of a high correlation between electrical resistivity and such soil properties as carbon and nitrogen content and silt content. The highest correlation (r > 0.9) was found for electrical resistivity and carbon content. It was also confirmed that significant correlations between electrical resistivity and soil properties are found mainly when soil properties are highly ranged. Perspectives for the applied method lie at the relationship between electrical resistivity and soil properties, such as texture class, clay content, carbon content, and cation exchange capacity. The results obtained in this work could be useful for complex precision agriculture, creating maps of agricultural soils, adequate methods of plant growth, and other issues of precision and conventional agriculture.

Due to a significant increase in mining activity and subsequent ecosystem disturbances, it is becoming increasingly important to understand how degraded, unproductive quarries can be converted into new, self-sustaining communities that develop into natural environments. Former limestone quarry was investigated with aim to determine the best reclamation practice for surfaces of former lime rock quarries. Effects of spontaneous succession and forestry reclamation restoration approaches on vegetation and soil features were studied. The study was conducted in one of the largest limestone quarries of the Leningrad region, south taiga region. Species composition and vegetation cover were estimated for different plant communities within each ecotype of the quarry. Also soil characteristics were evaluated at each plot. We found that the main differences between plots were due to their position in the landscape; the most similar communities colonize similar ecotypes. On flat landforms, biodiversity is reduced under biological reclamation. At the sites under spontaneous succession, the level of biodiversity increases. In terms of biodiversity conservation and economic benefit, spontaneous succession is preferable to forestry reclamation for the restoration of carbonate substrates. After examining CO2 emissions from the quarry as a result of weathering of carbonates and soil respiration, as well as the level of CO2 sequestration from the atmosphere, we show that the establishment of certain landscape forms within former quarries can help to reduce atmospheric CO2.

Active layer thickness and the depth of the permafrost are the basic features of the soil cover of the Arctic region. Urban ecosystems are characterized by disjunctive character of soil cover. Identification of separate soil bodies within the urban ecosystems, their spatial limitation and vertical stratification should be performed for adequate ecological assessment of urban territories. Methods of field electrophysics, which do not lead to any mechanical disturbances of soil cover, should be preferably used for both urban and natural environments. Studied soil profiles revealed significant differences in profile distribution of electrical resistivity values and active layer depths. Predominance of sand fraction in soil of Salekhard site (Spodic Cryosol) determines higher rates of thawing process compared to soil from natural site (Aquiturbic Cryosol), where clay is predominant fraction. Both soil profiles and their electrical resistivity curves are significantly affected by natural cryoturbation processes. However, vertical profile of electrical resistivity value in urban soil is more complicated and has a number of fluctuations due to higher rates of ground mixing, mechanical pressure and high amount of artefacts.

In recent decades rates of anthropogenic forcing on natural and urban ecosystems in the Arctic are increasingly growing. This tendency requires the development of more detailed environmental monitoring methods. In this context, study of background trace elements contents should be an urgent task. The purpose of authors study was an assessment of trace elements content in soils of urban environments in Yamal region and Murmansk. Twelve sites in Yamal region and four sites in Murmansk in different functional zones were studied during the investigation. Samples were taken from a depth of 0-5 cm and 5-20 cm. The highest contents for Cu, Zn, Ni were found in soil samples from Kharp, which was caused by existing chrome-processing factory. Soil samples from Aksarka and Labytnangi were characterized by the highest median values for Pb. Soil samples from Kharsaim and Kharp key plots were characterized by the highest median values for Zn. This could be explained by geological origin and high regional background concentration element for this trace element. Soil samples collected in Murmansk were characterized by highest medians in Pb, Ni and Mn in topsoil horizons, Mn and Zn in lower horizons. Evaluation of Saet´s index showed the predominance of non-hazardous Zc in most of the soil samples. Predicted climate change and consequent degradation of permafrost in soils could have the behavior of trace elements. Rates of accumulation, transformation, translocation, leaching and transportation of trace elements and other pollutants within the permafrost-affected landscapes could be affected and changed significantly.

This study examines the accessory wodginite and the discovery of titanium-bearing wodginite and Fe and Ti-bearing wodginite in lithium-fluorine granites from the Abu Dabbab and Nuweibi massifs in Eastern Egypt. The wodginite group's mineral association includes tantalum-bearing cassiterite and tin-bearing tantalum–niobate minerals: tantalite-(Mn), columbite-(Mn), and microlite. Three forms of wodginite crystallization were identified: (1) rims around columbite-(Mn) and tantalite-(Mn) varying from 1.5 to 21.9 μm in thickness, (2) micro-inclusions in cassiterite ranging from 5.4 to 27.0 μm in size, and (3) autonomous crystals measuring 3–124 μm in length. Wodginite in the Nuweibi massif is mainly found in porphyritic granite of late-stage porphyry intrusion. It has a similar composition to the worldwide wodginite of rare-metal granites, but exhibits a lower content of TiO2 (average 0.54%) and is a mineral indicator of rich tantalum ore deposits. In contrast, wodginite in the Abu Dabbab massif is replaced by titanium-bearing wodginite (Ti/(Sn + BTa + Ti + Fe3+) = 0.23) and is associated with Fe and Ti-bearing wodginite. Wodginite and Ti-bearing wodginite are maximally enriched in manganese (Mn/(Mn + Fe2+ +Ca) = 0.95), expressed in all intrusive phases of the massif, and are mineral indicators of tantalum-bearing granites with associated cassiterite-quartz mineralization. [ABSTRACT FROM AUTHOR]

Chile is a well-developed agricultural country, which is faced with the problem of agricultural soil contamination with metals, such as Cu, Cd, Pb and Zn, and metalloids (As). These elements can be retained by soils through different mechanisms, i.e., complex-forming with organic matter or occlusion within organic matter. That is why studying soil contamination should also be accompanied by detailed investigations of the soil organic matter composition. Soil organic matter is crucial for plant growth since its decomposition releases nitrogen, phosphorus and other nutrients available for the plants. 13C nuclear magnetic resonance spectroscopy, providing crucial data on carbon functional structures diversity, can also be used to study changes in the soil organic matter (SOM) during decomposition and humification. This study is aimed at investigating the molecular composition of the soil organic matter in the agricultural soils of urbanised areas of central Chile using 13C nuclear magnetic resonance (NMR) spectroscopy. The studied soils were characterised by almost neutral pH values and organic carbon contents from 1.7% to 5.2%. The results showed that soils with an increased content of the total organic matter demonstrated an increased portion of aromaticity and a decreased portion of aliphaticity. Most of the investigated humic acids show the highest peaks centred at 125 ppm, which can be tentatively assigned to aromatic alkene structures. The relatively high stabilisation rate of the organic matter in the studied soils can be explained by the mineralisation of its peripheral part, which, in turn, is explained by the decreasing C/N ratio values. The humic substances of the studied agricultural soils of central Chile showed a high average content of aromatic carbon, which is also typical for subboreal soils. [ABSTRACT FROM AUTHOR]

Floodplains are one of the most dynamic and youngest areas of the Earth's Quaternary surface. They are located in transitional conditions (land-ocean) of the permafrost zone of present and of particular interest for ongoing geochemical processes and soil/water balance. The soil thermal and water regimes of polar soils are crucial for the development of vegetation cover as well as production, accumulation and redistribution of organic matter. This work characterizes the hydrological properties of soils formed in Russian Arctic. The data showed differences in water holding capacity between soils formed in conditions of seasonal flooding (soil stratification, redistribution of organic and mineral matter through the soil profile) and those not influenced by flooding in Lena River Delta (gradual decreasing of water holding capacity as a function of depth). Both of the soil profiles from the Yamal Peninsula are characterized by a gradually decreasing water-holding capacity with depth. The hydrological regime characteristics were strongly related to the depth of the active layer. The intensity and rate of the thawing/freezing processes depends on the features of the hydrological regime. In this study, significant differences were noted in the soil characteristics of the two study areas. That is why the profile values of water-holding capacity differed among the study sites. The predicted global climate change and high sensitivity of Arctic ecosystems may lead to significant changes in permafrost-affected landscapes and may alter their water regime in a very prominent way, as permafrost degrades and lateral and vertical water flow in the basins of large arctic rivers changes. [ABSTRACT FROM AUTHOR]