Hydrocarbons In Bottom Sediments Research Articles

Distribution and Genesis of Aliphatic Hydrocarbons in Bottom Sediments of Coastal Water Areas of the Crimea (the Black and Azov Seas)

The aim of the article is to assess the level of aliphatic hydrocarbon (AHC) contamination in bottom sediments of the Azov–Black Sea coast of the Crimea, as well as to identify potential sources of its formation. Bottom sediment samples obtained from 19 stations during the research cruise of the R/V “Professor Vodyanitsky” (June 2020) were used as the material for this investigation. Sampling stations were located along the coast of the Crimean Peninsula and the Caucasus coastlines (the Black and Azov Seas). N-hexane extracts of sediments were studied by gas chromatography to determine the AHC amount and composition. It was established that AHC concentrations in the study area varied from 1.30 to 127.8 mg/100 g. Generally, bottom sediments of the Black and Azov Seas were characterized by low AHC contents, while increased AHC contents were found in the outer harbor of Sevastopol and Yalta regions. To identify potential hydrocarbon sources, various hydrocarbon markers were used. In most of the study areas, n-alkane composition was determined by similar sources of inputs and organic compound transformation. At the same time, oil pollution linked with use of fuel was recorded almost everywhere.

Nature of Hydrocarbons in Bottom Sediments of the European Arctic Seas

Nature of Hydrocarbons in Bottom Sediments of the European Arctic Seas

Concentration and Composition of Polycyclic Aromatic Hydrocarbons in Bottom Sediments of the Barents and Norwegian Seas

Concentration and Composition of Polycyclic Aromatic Hydrocarbons in Bottom Sediments of the Barents and Norwegian Seas

Hydrocarbons in bottom sediments of coastal waters of the Kazantip peninsula (Azov Sea)

The aim of the article is to study the bottom sediments of the coastal zone of Kazantip peninsula in the Sea of Azov of complexes of hydrocarbon pollution. This water area is a site with a high level of recreational load, despite the presence of a nature reserve there, and is also characterized by a rugged coastline, which causes the accumulation of pollution in bottom sediments. The material for the study was samples of the upper layer of bottom sediments, which were taken in the summer of 2021 in the coastal waters of Cape Kazantip (Sea of Azov) with a manual sampler from depths of up to 1.5 m both within the protected area and beyond its borders. Determination of hydrocarbons in bottom sediments was carried out by gas and liquid chromatography in accordance with certified methods. The paper presents new original materials on the distribution of hydrocarbons in bottom sediments in the area of Kazantip peninsula, as well as an assessment of the local level of pollution of marine soils in this area. The ratio of hydrocarbons of different origin in bottom sediments is given. In addition, possible ways and sources of pollution are indicated. As a result of the study, it was shown that the bottom sediments of the coastal zone of Kazantip peninsula are not polluted and the concentrations of the main groups of hydrocarbons are within the range of average values for the Sea of Azov. But, despite this, there are traces of fresh inflows of petroleum hydrocarbons, which can be of both anthropogenic and natural origin.

Bioindication of Bottom Sediments of the Gulf of Finland by the Composition of Meiobenthos in Combination with Biotesting and Chemical Analysis

The question of the possibility of using meiobenthos to monitor the state of bottom sediments (BS) in the Baltic Sea, where bottom macrofauna are unstable due to hypoxia, is of interest. The parameters of meiobenthos and the physicochemical characteristics of BS and bottom water were studied, and the toxicity of BS was determined by the survival of the amphipod Gmelinoides fasciatus in 10-day tests for 11 stations in the brackish part of the Gulf of Finland (depths of 10–52 m). Principal component analysis revealed two factors explaining 67% of the variability of the variables, and groups of stations similar in terms of conditions. Factor 1 combined nine related variables (depth, metal concentrations and fraction of sand in BS, ratio of nematodes and copepods (N/C index) and survival of amphipods), and factor 2 combined four variables (organic matter and polyaromatic hydrocarbons in BS, phosphates in water and the number of meiobenthos). Thus, bioindication of the environment by meiobenthos is promising, but requires an integrated approach to be applied in monitoring.

COMPOSITION OF BACTERIAL COMMUNITIES IN OIL-CONTAMINATED BOTTOM SEDIMENTS OF THE KAMENKA RIVER

The Kamenka River ows through the territory of the Kokuyskoye gas and oil eld located in the Perm Territory. Despite the absence of oil-producing facilities in the immediate vicinity of the river, oil hydrocarbons were found in the waters and bottom sediments at a concentration of 2445-25800 mg/kg. The composition of microbial communities of bottom sediments of the Kamenka River, located at the source and along the river, was studied. Using the methods of high-performance sequencing and bioinformatic data processing, it was established that the main share of microbial communities is represented by bacteria of the phylum Proteobacteria (16.7-30.3%), as well as the phyla Actinobacteriota, Bacteroidota, Bdellovibrionota, Campilobacterota, Chloro exi, Cyanobacteria, Deferribacterota, Desulfobacterota, Firmicutes, Gemmatimonadota, Methylomirabilota, Myxococcota, Nitrospirota, Patescibacteria, Planctomycetota, Spirochaetota, Synergistota, Thermotofota and Verrucomicrobiota. The values of the Shannon index for the studied communities are directly correlated with the concentration of petroleum hydrocarbons in bottom sediments. The phylum Proteobacteria in communities is represented by the classes Alphaproteobacteria and Gammaproteobacteria, among which representatives of the families Rhodobacteriaceae and Comamonadaceae dominate. When identifying to the genus, it was found that in the Comamonadaceae family, the main share is made up of bacteria of the genus Hydrogenophaga. It should be noted that bacteria of the genus Pseudomonas (class Gammaproteobacteria) were found only in the microbiocenosis of bottom sediments, characterized by the highest concentration of petroleum hydrocarbons.

Polycyclic aromatic hydrocarbons in bottom sediments of an inner-city lake in the zone of discharge of surface runoff

The study determined the content of polycyclic aromatic hydrocarbons (PAHs) in the bottom sediments of an inner-city Sredny Kaban Lake (Kazan, Russia) in the places of the organized release of untreated surface stormwater runoff within the catchment of the city. The content of 15 PAHs included in the priority list of PAHs for environmental research in the Russian Federation and in other countries was experimentally studied. The average content of the total PAHs studied (333.4 μg/kg) in the bottom sediments of the lake indicates a low degree of pollution. The analysis of the ratio of the content of individual PAHs reveals the main sources of their entry: fuel combustion (vehicles) and oil pollution of the surface water. Benzo(g,h,i)perylene and Benz(a)pyrene represent the largest contribution to the hazard coefficient of all studied PAHs for bottom sediments of the studied water body. Bottom sediments are composed mainly of particles with a size of 1–100 μm; the contribution of particles with a size of 0.1–1 μm was estimated to be up to 1%.

Polycyclic Aromatic Hydrocarbons in Bottom Sediments of Selected Anthropogenic Reservoirs in Terms of Catchment Area Development

The polycyclic aromatic hydrocarbon (PAH) concentration in the bottom sediments of the selected dam reservoirs is related to the catchment area size and length of the watercourse that supplies the reservoir. The anthropopressure increases the ratio of the PAH concentration sum G4 group to the G1 group. For the urban-industrial catchment area, the ratio is 1; for the agricultural and agricultural-forestral catchment area, the ratio is between 4 and 9. The elongated down time of surface run-offs helps to retain and degrade 2- and 3-ring PAHs, which is reflected in the high G4:G1 ratio value. Consequently, the pollutants are quickly delivered to the reservoirs and deposited in the bottom sediments. Under such conditions, the G4:G1 ratio is 1. The way in which the catchment area is developed shapes the proportions between the PAH groups that differ in the number of aromatic rings in their molecules. The toxicity, mutagenicity, and carcinogenicity coefficients calculated for the bottom sediments demonstrate that the limnic ecosystems supplied with water from the watercourses with urban-industrial catchment areas are far more threatened than the reservoirs supplied with watercourses with the agricultural catchment areas or catchment areas with a significant share (40–50%) of farming land.

Environmental State of a Small Northern River after an Emergency Discharge of Oil Products

The chemistry of surface water, bottom sediments, and zoobenthos communities is studied in a small forest watercourse after an accident on a petroleum pipeline. Nine months after the oil spill, the surface water downstream of the site of emergency discharge of oil-containing liquid still shows higher petroleum hydrocarbon content (2.8 MAC). The determined high concentrations of ions of iron (1.1−4.6 MAC) and copper (1.2−2.6 MAC), as well as difficult to decompose organic compounds (1.2−3.3 MAC), are also typical of the background area, thus suggesting their predominantly natural origin. The concentration of petroleum hydrocarbons in bottom sediments in water downstream of the emergency petroleum discharge site is 7–214 times its background value. The zoobenthos in the streams in the study area is represented by 18 groups of aquatic organisms, of which 14 are detected in the polluted zone. In the direction from the oil spill zone toward the mouth of the Vozei-shor Creek, the structure of zoobenthos changes and its quantitative characteristics decrease. Crustaceans and oligochaetes were found to dominate in the benthic communities of oil-polluted areas.

Оценка накопления углеводородов гидробионтами устьевой области реки Северной Двины

Приведены результаты исследования содержания массовой доли нефтеуглеводородов (НУ) в придонном слое воды, донных отложениях и тканях крупных двустворчатых моллюсков, собранных в устьевой области р. Северной Двины в течение 2009–2016 гг. в сезоны наибольшей фильтрационной активности моллюсков. Оценены уровни накопления НУ в воде, донных отложениях и тканях двустворчатых моллюсков устьевой области р. Северной Двины. Изучены зависимости между степенью накопления НУ в тканях двустворчатых моллюсков и уровнем загрязнения среды их обитания. Количественное определение содержания НУ в тканях двустворчатых моллюсков, воде придонного слоя и донных отложениях проводили флуориметрическим методом. Установлено, что массовая доля НУ в тканях двустворчатых моллюсков не превышает таковой для относительно чистых вод на всём исследованном участке реки. По показателю массовой доли НУ в донных отложениях устьевую часть р. Северной Двины можно отнести в основном к незагрязнённой и слабозагрязнённой (за исключением локальных участков в акватории реки в городской черте). В придонном слое воды в районе исследования показатель массовой доли НУ превышает государственные нормативы в отдельных точках отбора. Показано, что в условиях сложных градиентов среды необходим комплексный анализ биотических и абиотических факторов.

Scheme for Analytical Control of Oil and Biogenic Hydrocarbons in Bottom Sediments Using Gas Chromatography/Mass Spectrometry Technique

Scheme for Analytical Control of Oil and Biogenic Hydrocarbons in Bottom Sediments Using Gas Chromatography/Mass Spectrometry Technique

Scheme for Analytical Control of Oil and Biogenic Hydrocarbons in Bottom Sediments Using Gas Chromatography/Mass Spectrometry Technique

Scheme for Analytical Control of Oil and Biogenic Hydrocarbons in Bottom Sediments Using Gas Chromatography/Mass Spectrometry Technique

Hydrocarbons in the modern sediments of the Caspian Sea

The presented results have been obtained in a study of the concentrations and composition of aliphatic and polycyclic hydrocarbons in bottom sediments of Volga delta branches and in its shallow zone (2009–2010), as well as the Caspian Sea proper (2010–2013). Oil hydrocarbon pollution has been found to manifest itself mostly in Volga delta branches, which, despite the low concentrations (up to 54.5 μg/g), showed higher hydrocarbons share in Corg (up to 33.8%), while the composition of alkanes suggested their oil genesis. The geochemical barrier the Volga–the Caspian Sea prevents anthropogenic hydrocarbons from entering the open parts of the Caspian. Bottom sediments in the shallow zone of the Northern Caspian, represented by coarse-grained material, are now polluted by oil hydrocarbons to a lesser extent compared with other areas. The highest concentrations of aliphatic hydrocarbons (up to 178 μg/g) were recorded in the deepsea bottom sediments of Derbent Depression and in depressions of the Middle and Southern Caspian. These areas show a higher concentration of Corg (up to 9.884%) and a low concentration of hydrocarbons in Corg (up to 0.16%), while odd high-molecular homologues (n-C25–C31) dominate in the composition of alkanes.

Potential application of oil-suspended particulate matter aggregates (OSA) on the remediation of reflective beaches impacted by petroleum: a mesocosm simulation.

This paper presents the oil-suspended particulate matter aggregate (OSA) resulted from the interaction of droplets of dispersed oil in a water column and particulate matter. This structure reduces the adhesion of oil on solid surfaces, promotes dispersion, and may accelerate degradation processes. The effects of the addition of fine sediments (clay + silt) on the formation of OSA, their impact on the dispersion and degradation of the oil, and their potential use in recovering reflective sandy beaches were evaluated in a mesoscale simulation model. Two simulations were performed (21days), in the absence and presence of fine sediments, with four units in each simulation using oil from the Recôncavo Basin. The results showed that the use of fine sediment increased the dispersion of the oil in the water column up to four times in relation to the sandy sediment. There was no evidence of the transport of hydrocarbons in bottom sediments associated with fine sediments that would have accelerated the dispersion and degradation rates of the oil. Most of the OSA that formed in this process remained in the water column, where the degradation processes were more effective. Over the 21days of simulation, we observed a 40% reduction on average of the levels of saturated hydrocarbons staining the surface oil.

Distribution and composition of hydrocarbons in bottom sediments of the Shtokman deposit (Barents Sea)

The increased interest in investigation of hydrocar� bons (HCs) in Arctic seas is mostly explained by the huge oil and gas potential of the shelf and perspective exploitation of marine deposits. By now 11 oil and gas deposits have been discovered directly on the territory of the Barents Sea [1]. Intensification of oil produc� tion and transportation to the sea should result in an increase in the anthropogenic influence on the envi� ronment. In addition, we should note that HC intro� duction from sedimentary series increases in oil and gas regions [2]. The portion of filtered HCs in the World Ocean is estimated as 0.6 × 10 6 t/year, which is 46% of their total income in seawater (1.3 × 10 6 t/year from all sources in the absence of large accidents on average [3]). Oil filtration on the Russian Arctic shelf was originally described in the 16th century on the bank of the Ukhta River (northern Timan–Pechora area), where pitch lumps were found in sand [4]. Pro� cesses of such kind were later registered in the Chukhi, Bering, Barents, and Kara seas. In accounting for the high oil and gas potential of the Arctic shelf of Russia, we may assume that this natural source provides not less than 50% of the total oil introduction in the Arctic seas. Samples were collected on two polygons in the area of the Shtokman gas–condensate deposit (SGCD) in August 2010 (57th voyage of R/V “Academician Mstislav Keldysh) in order to estimate the level and composition of HCs in bottom sediments. Polygon 1 is located in the water area, where funneled deepenings of a seabed were registered (Fig. 1a); their formation may result either from melting of buried ice (potholes) or gas release on the seabed (pockmarks) [5]. Polygon 2 is located directly in the water area of the deposit (Fig. 1b). Bottom sediments were collected by a box corer and frozen at –18°C. Samples were thawed in the lab� oratory, dried at 50°C, and the fraction of 0.25 mm was separated. HCs were extracted by metylenchloride in an ultrasonic Sapfir bath, and their concentration was analyzed by IR spectrophotometry; the composi� tion of alkanes, by capillary gas–liquid chromatogra� phy; and the concentration and composition of poly� cyclic aromatic hydrocarbons (PAH), by the method of highly effective liquid chromatography. The details of methodological procedures were described in [2, 6].

Results of multiyear studies on the dynamics of pollution of lake Baikal by polycyclic aromatic hydrocarbons in the area waste water discharge from the Baikal Pulp and Paper Plant

New data on the concentration and spatial distribution of the benz(a)pyrene and polycyclic aromatic hydrocarbons in bottom sediments in the testing area of the Baikal Pulp and Paper Plant (BPPP) waste water discharge in 1981–1988 and 2010 are presented in this paper. The bottom sediments in this section of the lake are strongly polluted with polycyclic aromatic hydrocarbons.

Polychlorinated biphenyls and hydrocarbons in bottom sediments of Pechora Basin Rivers

The quantitative concentrations of 21 congeners of polychlorinated biphenyls and 16 priority polycyclic aromatic hydrocarbons were studied in bottom sediments of the Usa River, the largest Pechora’s tributary, and its tributaries located in the central part of Timan-Pechora petroleum province. In accordance with the classification of the regional and international standards, the pollution degree of bottom sediments by organic compounds of those classes was evaluated. Pollution profiles were examined and the character of the dominating source of polychlorinated biphenyls and polycyclic aromatic hydrocarbons for bottom sediments in the region under study was identified. Key words: bottom sediments, polychlorinated biphenyls, profiles of polycyclic aromatic hydrocarbons, petrogenic, pyrogenic pollution source.

Polycyclic Aromatic Hydrocarbons in Bottom Sediments from Three Water Reservoirs, Slovakia

Thirty-four sediment samples were collected in three water reservoirs from the Slovak Republic to investigate polycyclic aromatic hydrocarbon (PAH) distribution and predict their possible sources. The results showed that the highest total PAH concentrations were associated with sediments from the Velke Kozmalovce, ranging from 7,910 to 29,538 ng/g of dry weight. On the other hand, the lowest total PAH concentrations (84-631 ng/g of dry weight) were found in sediments of the Zemplinska Sirava, an important recreational area in eastern Slovakia. The distribution of individual PAHs was consistent within the three water reservoirs, and this together with diagnostic PAH ratios suggests mainly pyrolytic contamination of the sediments. However, petrogenic inputs appear to be important in the Zemplinska Sirava sediments.

The distribution and transformation of oil hydrocarbons in Onega Lake bottom sediments

The distribution of oil hydrocarbons in bottom sediments of Onega Lake was examined. Their qualitative and quantitative composition was examined by methods of IR-spectroscopy and chromatography-mass spectrometry. The background concentrations of oil hydrocarbons in bottom sediments are evaluated and the polluted area is determined. The major regularities in oil hydrocarbon transformations under natural conditions and anthropogenic impact are identified. The quantitative development of the bacterial groups that take part in the transformation of complex organic substances and oil product derivatives in the case of emergency pollution of Petrozavodsk Bay water area by oil products is demonstrated.

Concentration and composition of hydrocarbons in bottom sediments from the Sakhalin shelf

Aliphatic and polycyclic aromatic hydrocarbons were examined in the surface layer of bottom sediments from the eastern part of the Sakhalin shelf (the materials were sampled in the summer of 2002). The concentrations of hydrocarbons were determined to have changed since the beginning of the development of oil fields (compared with earlier years). According to the distribution of markers in the hydrocarbon compositions, the bottom sediments are dominated by allochthonous (terrigenous) hydrocarbons, which are the most stable compounds. The presence of transformed anthropogenic oil alkanes, which have never been found before, may be indicative of the increasing pollution of the region.