Polycyclic aromatic hydrocarbons in pyrogenic soils of swampy landscapes of the Meshchera lowland

The composition and distribution of polycyclic aromatic hydrocarbons (PAHs) were studied in organomineral and organic soils of the Meshchera National Park. It was found that the background oligotrophic peat soils unaffected by fires in central parts of the bogs are characterized by the increased PAH concentrations due to their high sorption capacity. The fires of 2007 and 2010 resulted in the transformation of the plant cover and soil morphology, the formation of new horizons, and the change in the PAHs content and composition. Significant burn-off of organic matter was found in oligotrophic-eutrophic soils and resulted in the decrease of PAHs content after fire. Only partial burn-off of organic horizons and intense formation of PAHs were recorded in the soil with initially great thickness of peat horizons. Pyrogenic accumulation of PAHs was identified in organomineral soils of the marginal parts of bogs and of forest sites.     

Lateral migration of soil solid-phase material within a landscape-geochemical arena detected using the magnetic tracer method

Thorough studies of the lateral migration of the solid soil material and the large-scale mapping of the soil cover have been performed within a landscape-geochemical arena in the small catchment area of the Lokna River basin (Tula oblast). Podzolized clay-illuvial agrochernozems are the predominant soils in the catchment area. Nine soil types from four orders according to the 2004 soil classification have also been described. The morphological analysis of the soil profile structures revealed their changes related to the lateral migration of the solid-phase products of the pedogenesis. From the estimated reserves of the spherical magnetic particles as tracers of the mass transfer, the accumulation and dispersion zones of the solid-phase material in the soil cover have been separated and conclusions about the genesis of these zones and their place in the migration structure of the catchment basin have been drawn. The soil catenas within the landscape-geochemical arena have been classified in accordance with the migration intensity of the soil solid-phase material, the localization of deposits, and the degree of openness of the soil-geochemical conjugations. The effect of the lateral migration of the soil solid-phase material on the structure of the microarena soil cover and the soil genetic profiles has been revealed.     

Input and behavior of polycyclic aromatic hydrocarbons in arable,fallow, and forest soils of the taiga zone (Tver oblast)

Contents of 11 most prevalent polycyclic aromatic hydrocarbons (PAHs) in snow and soils of arable, fallow, and forest areas significantly remote from impact technogenic sources of polyarenes have been examined in the Torzhok district of Tver oblast. From the analysis of snow samples, the volumes and composition of PAHs coming from the atmosphere onto the areas of different land use have been determined. Light hydrocarbons prevail in PAHs. They make up 65–70% of total PAHs; their share in soils reaches almost 95%. An increase in the content of PAHs is revealed in fallow soils compared to arable and afforested areas. A direct relationship is revealed between the lateral distribution of total PAHs and the content of organic carbon. The distribution of total PAHs is surface-accumulative in forest soils, mainly uniform in arable soils, and deepaccumulative in fallow soils. PAH groups characterized by similar radial distributions and ratios between their reserves in snow and soils are distinguished: (1) fluorene and phenanthrene, (2) biphenyl and naphthalene, (3) benzo(a)anthracene, chrysene, perylene, and benzo[a]pyrene, and (4) anthracene and benzo[ghi]pyrene.     

Indication and Quantitative Assessment of Polyarene Sources in Soils by Statistical Modeling (Oil and Gas Extraction Area,Volgograd Region)

Eurasian Soil Science - The polyarene complex of soils was investigated, and PAH sources were assessed quantitatively in soils in the area subjected to heterogeneous technogenic impact near the...     

Hydrocarbon status of soils under different ages of oil contamination

Modifications of the hydrocarbon status (HCS) of soils at the stages of the injection input of oil pollutants and the subsequent self-purification of the soil layer from technogenesis products have been revealed in studies conducted on an oil field. Comparison with the HCS of background soils has been performed. Changes in the composition and concentration of bitumoids, polycyclic aromatic hydrocarbons (PAHs), and hydrocarbon gases have been established. The HCS of a freshly contaminated soil is characterized by the predominance of butane (the highest component) in the gaseous phase, an abrupt increase in the concentration of second-kind bitumoids, and a 100-fold increase in the content of PAHs compared to the background soil. In the old contaminated soil, free and fixed methane becomes the predominant gas; the content of bitumoids in the upper soil horizons is lower than in the freshly contaminated soils by two orders of magnitude but higher than in the background soil by an order of magnitude; the PAH composition in the soil with old residual contamination remains slightly more diverse than in the background soil.     

Hydrocarbon status of soils under atmospheric pollution from a local industrial source

Contents and compositions of bitumoids, polycyclic aromatic hydrocarbons (PAHs), and free and retained hydrocarbon gases in soils along a transect at different distances from the local industrial source of atmospheric pollution with soot emissions have been studied. The reserves of PAHs progressively decrease when the distance from the source increases. Among the individual PAHs, the most significant decrease is observed for benzo[a]pyrene, tetraphene, pyrene, chrysene, and anthracene. On plowlands, the share of heavy PAHs—benzo[ghi]perylene, benzo[a]pyrene, perylene, etc.—is lower than in the forest soils. In automorphic soils of the park zone adjacent to the industrial zone, the penetration depth of four-, five-, and sixring PAHs from the atmosphere is no more than 25 cm. In soils under natural forest vegetation, heavy PAHs do not penetrate deeper than 5 cm; in tilled soils, their penetration depth coincides with the lower boundary of plow horizons. Analysis of free gases in the soil air revealed hydrocarbons only under forest. From the quantitative and qualitative parameters of the content, reserves, and compositions of different hydrocarbons, the following modification types of hydrocarbon status in the studied soils were revealed: injection, atmosedimentation–injection, atmosedimentation–impact, atmosedimentation–distant, and biogeochemical types.     

The Isotopic Composition of Carbon in Soil Lipids in the Oil and Gas Development Area in Volgograd Oblast,Russia

Eurasian Soil Science - Research data on the isotopic composition of carbon in soil lipids in the Zhirnovskoe and Bakhmet’evskoe oil and gas fields in the Medveditsa River basin, Volgograd...     

Diagnostics,Genesis, and Localization of Pedosediments within a Small Catchment (Central Russian Upland)

Eurasian Soil Science - Results of a detailed analysis of pedosediments—sediments composed of transported material of soil humus horizons—are discussed. Five main morphological features...     

Parameters of the Native Hydrocarbon Status of Soils in Different Bioclimatic Zones

Eurasian Soil Science - To characterize the native component of the hydrocarbon status of soils in different bioclimatic zones, representative soils were studied in the East European Plain within...