Phytoremediation Of Oil-contaminated Soil Research Articles

Natural Degradation Simulation and Phytoremediation of Oil-Contaminated Soil

In order to remediate the soils contaminated by oil and solve the disruption of ecological balance caused thereby, appropriate measures shall be taken to improve the oil degradation effect of the soil. This paper is based on study of current available soil remediation techniques of the oil-contaminated soil, focuses on the simulation of microbial degradation and phytoremediation techniques so as to conclude the corresponding degradation schemes with the optimal type of plants, which is aimed at providing the theoretical guidance for the actual remediation effect of oil contaminated soil.

Исследование детоксицирующей способности окисленных гуминовых веществ в условиях нефтяного загрязнения почв

The article presents the results of research on the oxidative modification of humic substances of brown coal of the Tyulgan deposit. The detoxifying effect of the obtained substances in relation to petroleum hydrocarbons was studied using the bioassay method. During the evaluation, a noticeable increase in the detoxifying ability was found in the result of chemical modification of humic substances. The greatest detoxifying effect in relation to oil pollution of the soil was observed for humic substances modified by oxidation and amounted to 19 and 42% at doses of 0.01 and 0.1% by weight. accordingly. The detoxifying effect of native humic substances is significantly lower: 9 and 2 % at doses of 0.01% and 0.1% by weight. accordingly. Thus, the prospects of using oxidized humic substances as sorbents-detoxicants during phytoremediation of oil-contaminated soil are shown.

Improving the efficiency of phytoremediation technologies of oil-contaminated soils with the participation of natural sorbents-meliorants

Phytremediation is considered to be a promising and environmentally friendly way to restore oil-contaminated soils. However, the multicomponent nature of oil pollution, its low bioavailability, high stability, hydrophobicity, and toxicity require a comprehensive approach to its implementation. The purpose of the study is to investigate the influence of different types of sorbents-meliorants and their complexes with remediation agents on improvement of the efficiency of phytoremediation technologies of oil-contaminated soils. The study established that the most effective plants for phytoremediation of oil-contaminated soils are Vicia faba var. Minor, Pisum sativum L., Avena sativa L., which are the least exposed to toxic effects of oil among the studied crops, and better adapt to the conditions of oil-contaminated soils. The influence of sorbent-meliorants such as glauconite, zeolite, sawdust, and sunflower husk on the process of phytoremediation of oil-contaminated soils (oil content 5%) was studied. It was proven that sunflower husk is the most promising and available agent for accelerating phytoremediation. The study examined the individual and combined influence of mineral fertilisers, biogenic surfactants of microbial origin, and humates on the growth of Avena sativa plants under conditions of oil pollution, as well as on the process of soil restoration. The best results are obtained by application of the above agents in combination with sunflower husk. This complex (sunflower husk + mineral fertilizers + surfactants of microbial origin / humates) has a positive effect on Avena sativa plants – reduces the rate of oxidative stress, which indicates an improvement in the adaptability of plants to oil-contaminated soil; growth parameters increase; plant biomass accumulation; the total content of chlorophyll a+b increases; and there is an improvement in soil properties by reducing the oil content in soil, reducing phytotoxicity, increasing dehydrogenase activity

Application of auxin producing bacteria in phytoremediation of oil-contaminated soil

Application of auxin producing bacteria in phytoremediation of oil-contaminated soil

Relationships between root growth of Zinnia hybrid “profusion orange” flowers and phytoremediation of oil-contaminated soil

Relationships exist between plant root growth and the phytoremediation of oil-contaminated soils. In a previous study, we demonstrated that zinnia flowers are well suited for the remediation of oil-contaminated soil. In this study, our goal was to quantify the relationship between zinnia root growth and purification of oil-contaminated soils. Three treatments were used: (1) cultivation of zinnia in oil-contaminated soil (contaminated pots), (2) cultivation in non-contaminated soil (non-contaminated pots), and (3) contaminated soil with no cultivation and only irrigation (irrigated pots). Growth of the Zinnia plants, including their roots, was significantly reduced in the contaminated pots compared with the noncontaminated pots. The soil dehydrogenase activity increased between 45 and 90 days after planting in all parts of the contaminated pots, especially the upper parts. The soil total petroleum hydrocarbon (TPH) concentrations in the contaminated pots decreased throughout the study period. Interestingly, the soil dehydrogenase activity increased, and the soil TPH concentration decreased even in lower parts of the pots where there was very little root growth. Therefore, the cultivation of plants can have a remediative effect on oil-contaminated soil even below the depth reached by the plant roots.

Formulation of a Multifunctional Biopreparations for Phytoremediation of Oil-Contaminated Soils: from Laboratory to Pilot-Industrial Technology

A formulation method for biopreparations stimulating phytoremediation of oil-contaminated soils based on rhizobacteria was proposed. Technology involves the cultivation of bacterial cultures Bacillus RB15 and Pseudomonas RB43 in a liquid nutrient medium, followed by concentration the biomass by centrifugation and drying the finished product by contact drying. The optimal temperature (23–30 °C) and the duration of the process (three days) were determined at the stage of preparation of the liquid preparation (cultural liquor CL rhizobacteria). A comparative analysis of the results of the concentration of CL using various methods – vacuum evaporation, ultrafitration and centrifugation showed that the application of the method of concentrating biomass in a centrifugal field is most suitable both for technological and operational characteristics. То obtain the finished dry form of preparation, the contact drying method is recommended. The parameter of preservation of the viability of RB cells was used as the main controlled parameter at all technological stages of production. To obtain the finished commodity form of the microbial preparation, it is proposed to use a complex sorbent as a filler in the standardization of the finished product, the moisture sorbent in contact drying, and the carrier for immobilization of bacterial cells. To promote the technology of biopreparations in practice, a pilot experimental industrial production and technological scheme of production were elaborated.

Spectrochemical Analytical Follow up of Phytoremediation of Oil-Contaminated Soil

ABSTRACTTotal Petroleum Hydrocarbons (TPH) are one of the most common groups of persistent environmental toxic organic contaminants to many organisms as well as to humans. In the present work, oil-polluted soil samples were phyto-remediated and analyzed. The investigated soil samples were collected from a location close to the oil petroleum production site in Ras-Gharib, Red Sea, Egypt. The phytoremediation process through TPH reduction and/or removal was carried out using Helianthus annuus (sunflower plant) based on its efficiency as a phytoremediator for organic pollutants. A preliminary four-week scheme of Helianthus annuus remediation, supported by twice quantized fertilization, provided a result of ∼56% clean soil. Contaminated and phyto-remediated samples were diagnosed and analyzed through particle size distribution, Carbon-Hydrogen-Sulfur-Nitrogen elemental analysis (CHSN), Organic Matter content (OM%), Total Petroleum Hydrocarbons determination (%) and spectroscopically through Laser Induced Breakdown Spectroscopy (LIBS) and Laser Induced Fluorescence (LIF). Promising results have been achieved indicating the feasibility of planting sunflower for effective TPH remediation of the polluted soil and also the possibility of in situ monitoring of the remediation with easy, cost effective and fast spectrochemical analytical techniques, namely LIBS and LIF.

Influence of biochar and compost on phytoremediation of oil-contaminated soil

ABSTRACTThe use of pyrolyzed carbon, biochar, as a soil amendment is of potential interest for improving phytoremediation of soil that has been contaminated by petroleum hydrocarbons. To examine this question, the research reported here compared the effects of biochar, plants (mesquite tree seedlings), compost and combinations of these treatments on the rate of biodegradation of oil in a contaminated soil and the population size of oil-degrading bacteria. The presence of mesquite plants significantly enhanced oil degradation in all treatments except when biochar was used as the sole amendment without compost. The greatest extent of oil degradation was achieved in soil planted with mesquite and amended with compost (44% of the light hydrocarbon fraction). Most probable number assays showed that biochar generally reduced the population size of the oil-degrading community. The results of this study suggest that biochar addition to petroleum-contaminated soils does not improve the rate of bioremediation. In contrast, the use of plants and compost additions to soil are confirmed as important bioremediation technologies.

The analysis of biological ways of restoration of the oil-contaminated soils

The aim of the article was the analysis of modern biological methods of restoration of oil-contaminated soils and possibilities of their use at the early stages of elimination of oil-contamination. The effective biological ways of restoration of contaminated soils include bioremediation and phytoremediation. The methods of bioremediation provide the activization of existing microflora by creation of optimal conditions at the expanse of tillage, mellowing, introduction of mineral manures, sorbents and other or use of microorganisms-oil-destructors, introduced in contamined soil in significant amounts. Bioremediation utilizes the oil hydrocarbons rather successfully. But this method has a series of disadvantages, especially – many stages, high cost prices, conditioned by additional expenditures for preparatory works and for creation of the optimal conditions of bioremediation. At the same time the artificial introduction of microorganisms in oil-contaminated soils is connected with certain biological risk. The methods of phytoremediation are effective and attractive because of their naturaless, eco-friendliness, easiness and economy, are characterized with longer influence and stable improvement of environmental situation. The analysis of literary data demonstrated that the prospective plants for restoration of oil-contaminated soils are legumes, able to assimilate the nitrogen of atmosphere, perennial herbal plants and stable arboreal species, able to symbiosis with nitrogen-fixing microorganisms. The analysis of the literary sources of biological ways of restoration of oil-contaminated soils indicates the prospectiveness of phytoremediation methods using perennial actinorhizal plants, especially sea buckthorn that can be used independently for restoration of oil-contaminated soils. This methos is characterized with economy, esthetics, relative easiness of realization, possibility of usage on big areas and prolongation of effect. Phytoremediation of oil-contaminated soils using sea buckthorn alongside with cleansing of pollutants provides the improvement of physical-chemical and biological properties of soil, prevents erosion, restrains the penetration of harmful substances in air, soil and underground water that provides the stable restoration of natural ecosystems

PHYTOREMEDIATION OF OIL CONTAMINATED SOIL USING SEA BUCKTHORN

Here we presented the potential phytoremediation of oil contaminated soil using Sea Buckthorn. Sea Buckthorn successfully adapts to adverse conditions of the oil-contaminated soils and provides the high level of cleaning oil-contaminated soils from oil up to 92.7%, on the fourth year of growth. Sea Buckthorn improves microbiological properties of soil: increases the heterotroph microorganisms by 10 4 times, oil destructive microorganisms – by 6×10 2 , nitrogen-fixing microorganisms by 10 times; moreover, it eliminates soil toxicity, increases content of total nitrogen and ammonia. The surface root system of Sea Buckthorn forms well developed root sprouts, that successfully extends to neighboring areas, improves water-air properties, contributes to the rapid formation of dense soil cover, biomass accumulation, formation of humus and provides prolongation of phytoremediation action. Sterility of pollen and content of carotenoid in Sea Buckthorn leaves in the conditions of oil-contamination were within normal range and testifies to the plant tolerance towards oil contamination. Sea Buckthorn improves the physical, chemical and biological properties of soils, reduces oil contamination, protects the oil contaminated soils from erosion. We could recommend this species for the phytoremediation of oil contaminated soil.

Treatment and Remediation of Petroleum-Contaminated Soils Using Selective Ornamental Plants

Pot-culture experiments were carried out to assess the phytoremediation potential of 14 ornamental plants in weathered petroleum-contaminated soil, which was collected in the Shengli Oil Field, one of the biggest oil fields in China, by examining their impact on the degradation potential of total petroleum hydrocarbons (TPHs) and its composition. Results showed Gaillardia aristata, Echinacea purpurea, Fawn (Festuca arundinacea Schreb), Fire Phoenix (a combined F. arundinacea), and Medicago sativa L. could effectively reduce TPHs and its composition in 10,000 mg kg(-1) TPH-contaminated soil. After a 30-day pot-culture experiment, the removal rates were 37.16%, 46.74%, 49.42%, 41.00%, and 37.93%, respectively, significantly higher than that in the control (only 12.93%). Removal rates of TPH composition including saturated hydrocarbon, aromatic hydrocarbon, asphaltene, and polar compound reached 39.41%, 38.47%, 45.11%, 42.92%, and 37.52%, respectively, also higher than that in the control (only 6.90%). Further, the total biomass did not significantly decrease for all plants tested in 10,000 mg kg(-1) TPH-contaminated soil. Fourier transform infrared spectroscopy confirmed the presence of oil in the plant tissues. These results suggested that the typical ornamental species including G. aristata, E. purpurea, Fawn, Fire Phoenix, and M. sativa can be adopted in phytoremediation of oil-contaminated soil.