Resistance of Different Plant Species to Oil Pollution

This research work was designed to compare and evaluate the capacity of microbes in bioremediating and biodegrading of hydrocarbons which are the major constituents of petroleum oil. An oil spill is a leakage from ocean-going tankers, pipelines or other oil sources. Bioremediation for oil spills is a technique that uses microbes to eliminate contamination of hydrocarbons from water and soil, thereby making them safe for aquatic and terrestrial species. Bioremediation can be used by bacterial species, fungal species (by a process called mycoremediation) and plant species (by a process called phytoremediation). Two different species—bacterial species (Pseudomonas putida) and fungal species (Penicillium chrysogenum)—were checked individually in the laboratory condition, in order to determine and test for their capabilities in bioremediation process in oil spills. The total aerobic bacterial and fungal counts and cfu result were carried out after first and second weeks of inoculation, and was found to be significant. Solvent extraction method was primarily used to determine the percentage of oil degraded. P. chrysogenum degraded 11.1% of the oil in two weeks and P. putida degraded 6.425% after two weeks; this shows P. chrysogenum was found to degrade oil better than P. putida. Gas chromatographic (GC-MS) analysis of the residual oil extracted from bacterial, fungal as well as the control set up showed marked variations in peaks representing individual hydrocarbon components being degraded and transformed. Higher degradation was obtained with P. chrysogenum having lower peaks as compared to the bacterial and the control set up. This further confirmed the result obtained earlier with the solvent extraction method. There are three methods to clean up oil spills— physical, chemical and biological (bioremediation); but bioremediation is advantageous as it is time and cost saving than physical metho. Also unlike chemical method, no foreign or toxic chemicals are added to the site. Keywords: oil spills, hydrocarbons, bioremediation, Pseudomonas putida, Penicillium chrysogenum Cite this Article Singh R, Majumdar RS. Comparative Study on Bioremediation for Oil Spills Using Microbes. Research & Reviews: A Journal of Bioinformatics . 2017; 4(1): 16–24p.

Biodiversity loss remains a global challenge, and monitoring methods are often limited in their coverage. Rivers State is a biodiversity hotspot because of the high number of endemic species endangered by oil pollution. This thesis investigates the potential of integrating remote sensing tools for monitoring biodiversity in the State using vascular plant species as indicators. Satellite data from Hyperion, Sentinel 2A and Landsat were analysed for their usefulness. Soil samples from polluted and control transects were analysed for total petroleum hydrocarbon (TPH), phosphorus (P), lead (Pb), temperature, acidity, species diversity, abundance and leaf chlorophyll concentration. Field data results showed significant differences in all variables between polluted and control transects. Average TPH on polluted transects was 12,296 mg/kg, and on control transects was 40.53 mg/kg. 163 plant species of 52 families were recorded with Poaceae and Cyperaceae the most abundant. Floristic data ordinated on orthogonal axes of soil parameters revealed that TPH strongly influenced species occurrence (r = -0.42) and abundance (r = -0.39). Similarly, application of the spectral variability hypothesis (SVH) revealed the underlying environmental gradient controlling vegetation composition on polluted transects as TPH and on control transects as P. Models of relationship between spectral metrics and soil properties estimated soil TPH (R2 = 0.45) and P (R2 = 0.62) with marginal errors. Hyperion data provided better insight into vegetation response to oil pollution. Continuum removed reflectance, band depths of absorption maxima, red edge reflectance all significantly differed between polluted and control vegetation. Furthermore, a new index created from TPH sensitive Hyperion wavelengths- normalised difference vegetation vigour index (NDVVI) outperformed traditional narrowband vegetation indices (NBVIs) in models estimating species diversity in Kporghor. R2 and RMSE values for Shannon’s index were 0.54 and 0.5 for NDVVI-based models and 0.2 and 0.67 for NBVI-based models respectively. This research provides evidence of oil pollution effect on vegetation composition, abundance, growth and reflectance and outlines how this information can be used for biodiversity monitoring.

The rapid growth of economic development in Egypt over the last few decades has led to numerous offshore projects, expanding maritime facilities and a vast spread of coastal tourist developments. However, adequate capacity building of existing national oil spill response facilities did not complement such growth. This has resulted in an imbalance between the degree of environmental exposure and level of preparedness to respond to potential oil and chemical spills that may occur along these highly sensitive coastal areas and to the marine environment of Egypt. Both the Red Sea and Mediterranean coasts of Egypt support thriving ecosystems and a substantial tourist industry centered around golden beaches, crystalline waters, and a plethora of plant and animal species that exist nowhere else on earth. At the southern tip of the Sinai Peninsula Ras Mohammad National Park alone shelters over 130 species of coral and 116 species of fish. Only a few kilometers away, the Gulf of Suez is one of the worlds busiest industrial shipping routes. More than 117 million tons of oil pass through Egyptian waters each year and cross Egypt's main land through the SUMED pipeline from Ain Sukhna terminal (at the head of the Gulf of Suez) to Sidi Krir terminal on the Mediterranean. Another 28 to 30 million tons of oil go through the Suez Canal directly and there is a 15000-ship movement every year in Egypt. The Egyptian Environmental Affairs Agency (EEAA) has updated a National Oil Spill Contingency Plan (NOSCP), prepared in 1986 by the petroleum sector, in 1998. The NOSCP is the national framework for action in the event of an oil pollution incident. Updating, the NOSCP was just the beginning and not the end of the road. Challenges to take forward necessary action at all response levels to ensure efficiency of application of the NOSCP are enormous. Over the last few years concerned parties and stakeholders conducted several investigations and assessment to identify critical areas of concern and high exposure. Many assessment reports have identified gaps and addressed required measures needed to enhance bridging those gaps and restore the required balance between exposure and preparedness to recover from this situation. This paper considers the present status of the imbalance between environmental exposure and oil spill response preparedness along Egyptian coastline, describes current status of the NOSCP and the recovery measures taken to improve the situation and ensure credible response to potential major spills.

The aim of this study was to screen plant species for remediation of oil-polluted soil in a semi-arid loess area. Pot experiments were conducted to test six indigenous plant species: ryegrass (Lolium perenne), tall fescue (Festuca ovina), wheatgrass (Agropyron cristatum), alfalfa (Medicago sativa), erect milkvetch (Astragalus adsurgens), and caragana (Caragana korshinskii). Loessial soil was spiked with crude oil at five pollution levels (0, 0.5, 1, 2, and 4%, w/w). We analyzed plant growth parameters at different stages, soil oxidoreductase activities, and oil degradation rate under different treatments. Soil pollution by oil negatively affected the germination rate, plant height, and biomass of all six species while inhibiting soil dehydrogenase and catalase activities. These inhibitory effects increased with increasing oil pollution level, with 2% and 1% being the critical levels at which plant growth and soil oxidoreductase activities were significantly inhibited, respectively. Both oxidoreductase activities in the rhizosphere soil were significantly higher than those in the bulk soil, which led to a considerable increase in the degradation rate of total petroleum hydrocarbons (TPHs) in the rhizosphere. The plants showed varying remediation effects in the oil-polluted soil. Erect milkvetch and caragana showed potential for remediation of soil below the 0.5% pollution level, alfalfa for soil below the 1% pollution level, and ryegrass, tall fescue, and wheatgrass for soil below the 4% pollution level. The oil pollution level was negatively correlated with plant height, biomass, oxidoreductase activities, and TPH degradation rate for the six plants (p < 0.01), whereas plant biomass was positively correlated with plant height and TPH degradation rate (p < 0.01). Dehydrogenase activity was significantly positively correlated with catalase activity (p < 0.01), while both of them were positively correlated with TPH degradation rate (p < 0.05 and p < 0.01, respectively). In conclusion, the six indigenous plants exhibited different tolerances to oil pollution, among which ryegrass, tall fescue, and wheatgrass had the greatest potential for remediation of oil-polluted soil in the loess area.

In 2005, it was estimated that over 70% of oil spills in Colombia affected riverine areas. The Magdalena River is the longest navigable river in the country. It is home to countless species of flora and fauna, and provides important services as both a resource and a river transport route. Hydrocarbons represent 91% of products carried on the river. Mitigation associated with oil spill impacts depends largely on the formulation and implementation of adequate contingency plans, which should incorporate the identification of sources of oil spills, the simulation of the respective dispersion patterns and the characterization of areas that could be affected by a spill. Several different types of oil spills in the Magdalena River were simulated in order to assess the possible spill behavior, based on an analysis of sites at risk of releasing oil into the water stream, and considering the characteristics of the products most frequently transported along the river or used as fuel for boats. Taking into account the seasonal variability in river level and river flow, two different scenarios were simulated: rainy season (which usually floods in the surrounding area of the river) and normal season (when the river is within its usual margins and is navigable on most of its reaches); the dry season was not simulated at the time of this paper because of missing shoreline information. The results show considerable differences in the behaviour of the spilled oil under different climatic seasons. Therefore, this type of analysis is suitable to use for the formulation of refined plans for effective and efficient spill response and mitigation.

Ships that transport oil or derivatives on the Lower Amazon River waterway are at a considerably high risk of suffering spills, with severe environmental and socioeconomic consequences. The present study is aimed at modeling and simulating the oil dispersion and magnitude of these accidents in terms of the vulnerability of biological resources, considering two oil types most often transported by medium-sized tankers in the region (S500 and S10). The study method was as follows: (a) secondary data were collected from local species, and the coastal sensitivity index (CSI) was calculated, obtained from Brazil's Letters of Environmental Sensitivity to Oil Spill (Cartas de Sensibilidade Ambiental ao Derramamento de Óleo (SAO)); (b) ship traffic information was obtained from Brazil's Statistical Yearbook of Waterway (Anuário Estatístico Aquaviário (ANTAQ)); (c) modeling and numerical simulation of oil spills in water were performed, in order to investigate dispersion scenarios (SisBaHia); (d) three numerical scenarios of oil plume dispersion (in May and November) were integrated to assess species vulnerability in three zones of environmental interest (I, II, and III). Some species identified in zone II were considered to be the most vulnerable (fish, plankton, aquatic mammals, amphibians, aquatic invertebrates, trees, and plants), with the mammal Sotalia fluviatilis being at risk of extinction (Gervais & Deville, 1853). The simulated scenarios showed that contingency plans should have a minimum response time of 3h and a maximum response time of 72h to prevent the oil plumes from dispersing as far as 170km longitudinally, depending on the zone, season, and tidal phase. Thus, a total of 62 sites of biological resources were identified in the literature recorded from 2016. Considering them, 324 species of flora and fauna were recorded, distributed in the following seven groups: (i) 49 tree and plant species, (ii) 37 amphibian species, (iii) 2 aquatic invertebrate species, (iv) 23 invertebrate species, (v) 1 aquatic mammal species, (vi) 95 fish species, and (vii) 117 planktonic species. A failure to respond to these accidents would impact immense intact aquatic areas and ecosystems, with unpredictable consequences for local biodiversity conservation.

The objective of this study is to investigate the physiological mechanisms of plant adaptation under crude oil contamination of soil. Different plant species used in the study sedge (Carex hirta L.), bean (Faba bona Medic.), alfalfa (Medicago lupulina L.) and clover (Trifolium pratense L.) showed various biochemical and morphological reactions under oil pollution. The effect of crude oil on root elongation, shoot growth and dry matter accumulation of the four species was evaluated. All investigated plant species under oil contamination formed powerful root system, however the growth of plant aboveground part was diminished. Results of phytohormones content investigation in C. hirta confirmed that the morphological growth reactions occurred due to changes in phytohormonal balance of plants. Crude oil reduced amount of main growth activator auxin in sedge leaves and stimulated the increase of abscisic acid amount. In sedge roots auxin accumulation occurred under oil contamination. We studied antioxidant system of C. hirta and F. bona plants under oil pollution. Results of our investigations show that for adaptation under oil pollution sedge plants accumulate low molecular weight antioxidants, e.g. polyphenols and maintain reduced cell status due to high reduced/oxidized glutathione ratio in root system. In roots of F.bona activation of antioxidant enzymes catalase and peroxidase under oil effect occured. It was shown that crude oil effects nitrogen metabolism in alfalfa and clover plants. The amount of non-protein and amine nitrogen in plants increased, while the proportion of protein nitrogen decreased under oil contamination. To improve soil nitrogen supply we inoculated the seeds of alfalfa and clover with 348a, BN9 and A91 strains of Rhizobium leguminosarum bv. trifolii for intensification of nodulation in oil contaminated soil. Although the number of nodules on plant roots in oil contaminated soil decreased, their weight was greater than in the control. Improvement of plants nitrogen nutrition in oil contaminated soil requires further investigations.

This paper deals with the effects that formation fluids have on animal and plant life. Crude oil is a mixture-not only of hydrocarbons, but of suspended salts and of sulphur compounds. The toxicity of some of the hydrocarbons and some of the sulphur compounds is discussed, as is the toxicity of salt. Consideration is also given to the complexity of the hydrocarbon components and the influence of refining methods on toxicity. Some mechanisms by which an animal system may attempt to overcome injurious effects are outlined. Finally, methods of aiding recovery are suggested. Introduction Formation or connate fluids consist of mixtures of hydrocarbons and salt water, and mal' also contain various amounts of sulphur compounds, such as hydrogen sulphide and rnercaptans. These components may be present in almost all conceivable proportions-some formation fluids contain no water, some are all water, some consist of only light hydrocarbons (i.e. natural gas) and some contain only very heavy hydrocarbons. Also, these fluids may be sour (containing sulphur compounds) or they may contain no sulphur compounds and are referred to as being sweet., This is largely dependent on the formation of origin. Unfortunately, therefore, a spill of formation fluid will often present more than a crude oil spill problem. Each of the major components of the connate fluid can generate its own set of unique problems. The causes of these problems often obscure each other to the extent that what appears to be a simple oil spill may not respond to treatment. Examination and analysis may show, for example, that the oil spill also contained a salt spill. The salt could have been present in the crude oil as free brine, as emulsified salt water or as suspended micro-crystals in the oil. A high concentration of salt in the oil could have a serious effect on he rehabilitation program. Crude oils have been tested hich contained 20,000 lbs of salt per 1000 barrels of oil. A crude oil spill may therefore consist of three intertwined problems:a hydrocarbon problem;a mercaptan and hydrogen sulphide problem;a salt problem. The Hydrocarbon Problem The hydrocarbons in crude oil are present in a variety of forms; some are volatile, some are waxy solids and some are tarry solids, depending on the kind of crude oil that is involved. Crude oils may be categorized as several types:paraffinic - straight-chain saturated hydrocarbons.naphthenic - cyclic compounds, partially saturated.aromatic - having benzene rings in their structure.asphaltic - generally containing some of the above, but having greater chain length, and having other elements. Each of these types of crude oils has a light (gasoline-like) fraction and several heavy (oily, tarry or waxy) fractions. Each fraction has a different solubility in water, and usually this appears to modify the over-all undesirable effects on various species of animals and plants encountering the crude oil. These undesirable effects will be referred to throughout this paper generally as toxicity.

The oil industry in Nigeria is known to be as a source of revenue and foreign exchange earning to the economy. However, while the industry is perceived as an engine of growth, it is regarded as a mixed blessing to the country. This is as a result of distortions in the environment due to oil spillages and contamination of agricultural lands. Based on these problems, the paper examine the qualities of surface and well waters, bottom sediments, river banks soils and some species of plants in areas of oil exploitation and exploration. Samples of well and surface water, bottom sediments and riverbank soils were collected during the month of June and September 2013. These samples were sent to the laboratory for physio-chemical analysis. The result shows that the values of some samples in some locations were slightly higher than the WHO permissible level for portable water, the same was found in chemical parameters, indicating some level of pollution due to oil spillage. Riverbanks soil values were slightly higher than those of the bottom sediments. Of the twenty-four species of plants evaluated, twenty were impacted slightly due to absorption of toxic nutrients from spilled oil and four non-impacted by oil pollution. To ensure the restoration of the ecosystem, such preventive measures of regulating the activities of oil companies, checking pipe line vandalization, accidental discharge, pre and post-impact assessment by such oil companies should be carried out annually. Lastly, government should enforce pollution control measures and environmental friendly standards. DOI: 10.5901/mjss.2014.v5n27p1678

One way to identify hydrocarbon-tolerant plant species for reclamation is to sample vegetation at contaminated sites allowed to recover naturally. We compared vegetation and soils of 14 hydrocarbon-contaminated plots in southern Saskatchewan to those of nearby uncontaminated plots to determine the impact on plant communities and soil properties. Contaminated plots had less vegetation and litter cover than uncontaminated plots, and significantly higher soil carbon to nitrogen ratios, pH, and hydrocarbon concentration, and lower nitrogen and phosphorus. Although species richness was not significantly different, Shannon's diversity was lower on contaminated plots. Mean compositional similarity of the plots, measured using Jaccard's index, was only 31%, and cover similarity, measured using Spatz's index, was only 22%. Vegetation composition differences occurred because mycorrhizal, woody and vegetatively reproducing species, and species using birds or unassisted means for seed dispersal were significantly less common on contaminated than uncontaminated plots. Self-pollinated species were significantly more common on contaminated plots. The most abundant species on contaminated soils were the annual forb Kochia scoparia and the native perennial grasses Hordeum jubatum, Distichlis stricta, Agropyron smithii, Agropyron trachycaulum, and Poa canbyi. This research shows that some plant species and functional groups are tolerant of the altered soil conditions at hydrocarbon-contaminated sites.Key words: functional groups, oil spills, phytoremediation, reclamation, succession, vegetation recovery.

In this paper, a viability study is conducted for a bioremediation intervention in a cultivated area contaminated by a pipeline oil spill. In this context, green technologies such as bioremediation and phytoremediation could represent an optimal solution for reducing pollution without deteriorating soil quality. The phytoremediation test was conducted at the microcosm scale using three plant species (Zea mays, Lupinus albus and Medicago sativa) and at the mesocosm scale (Zea mays), also evaluating the application of plant growth-promoting bacteria (PGPB). The results showed that the selected plants, being able to grow satisfactorily, are able to lessen the presence of hydrocarbons in the soil. An increase of 15–18% in the degradation of the C &gt; 12 fractions in vegetated soils was observed, confirming the effect of plants on the biodegradation of hydrocarbons in the soil. Moreover, a further improvement was recorded after adding PGPB, resulting in fresh biomass production being up to 50% higher than the controls and the degradation of the C &gt; 12 fraction increasing by up to an additional 10%. Particular attention was also paid to pyrene, considered an indicator of PAH contamination. At the end of the experimentation in vegetated soils, pyrene removal reached values above 50%. By favoring plant growth, the addition of PGPB resulted in a further up to 20% reduction in the content of the contaminant in the soil. The primary role of the plants in soil contaminated by petroleum derivatives was to accelerate the degradation of contaminants through the stimulation of microbial activity. Therefore, the cooperation between plants and microorganisms can be concretely used as a nature-based solution in a sustainable and economical way.

An ecological impact assessment of crude-oil spills was carried out on the environment of an oil-rich community in the Niger Delta of Nigeria. Samples of the topsoil (0−15 cm), subsoil (15−25 cm) and the dominant species Gamba grass ( Andropogon gayanus ) were collected using the transect method from the point of spills. The samples were also collected from an unimpacted location (control). The samples were wet-digested and the concentrations of Pb, Cd, Cu, and Zn were determined by flame atomic absorption spectrophotometry, while the physico-chemical properties of the topsoil were determined by standard methods. The data were subjected to Student t test, ANOVA and Pearson correlation analysis, and the models for pollution assessment were employed to assess the pollution status of the soil and plant species. The results showed that concentrations of Pb, Cu and Zn in the topsoil exceeded international standards at close proximity to point of spills (0−200 m), while Cd concentrations exceeded the international standard at all the locations. Only Cd exceeded the international standard in the subsoil. Contamination ( P i ) and integrated pollution ( P c ) indices of the topsoil showed reducing trends from the point of pollution, and locations at 0 m and 100 m exhibited high P c , while those at 200 m showed moderate P c by all metals. The levels of Pb and Cd in the diagnostic species exceeded the World Health Organization limits and the pollution load index (PLI) portrayed severe contamination. In conclusion, the impact of crude-oil spills in the area was significant; soil remediation is important to avert ecological and human health disasters. Moreover, these findings will be useful for designing strategic measures for environmental control in the area. DOI: http://dx.doi.org/10.5755/j01.erem.71.3.12474

A feasibility study is presented for a bioremediation intervention to restore agricultural activity in a field hit by a diesel oil spill from an oil pipeline. The analysis of the real contaminated soil was conducted following two approaches. The first concerned the assessment of the biodegradative capacity of the indigenous microbial community through laboratory-scale experimentation with different treatments (natural attenuation, landfarming, landfarming + bioaugmentation). The second consisted of testing the effectiveness of phytoremediation with three plant species: Zea mays (corn), Lupinus albus (lupine) and Medicago sativa (alfalfa). With the first approach, after 180 days, the different treatments led to biodegradation percentages between 83 and 96% for linear hydrocarbons and between 76 and 83% for branched ones. In case of contamination by petroleum products, the main action of plants is to favor the degradation of hydrocarbons in the soil by stimulating microbial activity thanks to root exudates. The results obtained in this experiment confirm that the presence of plants favors a decrease in the hydrocarbon content, resulting in an improved degradation of up to 18% compared with non-vegetated soils. The addition of plant growth-promoting bacteria (PGPB) isolated from the contaminated soil also promoted the growth of the tested plants. In particular, an increase in biomass of over 50% was found for lupine. Finally, the metagenomic analysis of the contaminated soil allowed for evaluating the evolution of the composition of the microbial communities during the experimentation, with a focus on hydrocarbon- oxidizing bacteria.

Oil spill in the Central Patagonian zone was studied to evaluate if any relationship exists between the parameters used to characterize weathering spilled oil and soil toxicity for two plant species and to evaluate if the phytotoxicity to local species would be a good index for the soil contamination. Nuclear magnetic resonance (NMR) structural indexes and column chromatography compositional indexes were determined to characterize the oil spill in the soil samples. Bioassays were also carried out using Lactuca sativa L (reference) and Atriplex lampa (native species) as test organisms. Measurements of the total petroleum hydrocarbon (TPH) and the electrical conductivity (EC) of the soil were carried out to evaluate the effect on the bioassays. The principal components analysis of the parameters determined by NMR, compositional indexes, EC, TPH, and toxicology data shows that the first three principal components accounted for the 78% of the total variance (40%, 25%, and 13% for the first, second, and third PC, respectively). A good agreement was found between information obtained by compositional indexes and NMR structural indexes. Soil toxicity increases with the increase of EC and TPH. Other factors, such as, the presence of branched and aromatic hydrocarbons is also significant. The statistical evaluation showed that the Euclidean distances (3D) between the background and each one of the samples might be a better indicator of the soil contamination, compared with chemical criterion of TPH.

Despite the severe impacts of the Deepwater Horizon oil spill, the foundation plant species Spartina alterniflora proved resilient to heavy oiling, providing an opportunity to identify mechanisms of response to the anthropogenic stress of crude oil exposure. We assessed plants from oil-affected and unaffected populations using a custom DNA microarray to identify genomewide transcription patterns and gene expression networks that respond to crude oil exposure. In addition, we used T-DNA insertion lines of the model grass Brachypodium distachyon to assess the contribution of four novel candidate genes to crude oil response. Responses in S. alterniflora to hydrocarbon exposure across the transcriptome as well as xenobiotic specific response pathways had little overlap with those previously identified in the model plant Arabidopsis thaliana. Among T-DNA insertion lines of B. distachyon, we found additional support for two candidate genes, one (ATTPS21) involved in volatile production, and the other (SUVH5) involved in epigenetic regulation of gene expression, that may be important in the response to crude oil. The architecture of crude oil response in S. alterniflora is unique from that of the model species A. thaliana, suggesting that xenobiotic response may be highly variable across plant species. In addition, further investigations of regulatory networks may benefit from more information about epigenetic response pathways.