Crude Oil Pollution

The present study was undertaken to know the density and diversity of collembolans in Majuli river island during 2015-16. Altogether 1354.55 individuals of Collembola were extracted, which revealed the presence of 5 species viz., Cyphoderus sp., Entomobrya sp., Isotoma sp., Folsomia sp. and Hypogastrura sp. belonging to 4 families viz., Cyphoderidae, Entomobryidae, Isotomidae and Hypogastruridae. Cyphoderus sp. was recorded to be the most abundant species contributing 37.74 percent of population. During the study period, the diversity was recorded to be higher during summer indicating the presence of relatively stable habitats as compared to other seasons. The highest density (196.36 nos./sq.m.) of Collembola was registered during the summer season and the lowest during the winter season (39.09 nos./sq.m.). Monthly variation of collembolan density revealed the maximum population of Collembola during the month of August (206.82 nos./sq.m.) whereas minimum was registered during February (27.27 nos./sq.m). Correlation studies revealed a significant positive correlation of collembolan density and diversity with soil moisture (Density, r= 0.929, 0.923, 0.824 and 0.945); (Diversity, r= 0.702, 0.867, 0.622 and 0.904) and organic carbon (Density, r= 0.873, 0.973, 0.787 and 0.915); (Diversity, r= 0.732, 0.667, 0.735 and 0.843) during all the seasons, respectively. Other soil physicochemical properties viz., sand, silt, clay, soil microbial biomass carbon, pH and bulk density did not exhibited any distinct relationship with both the density and diversity of the collembolans.

Arrangement and Implications in South Asian Region Degree: Increasing marine transportation of oil inevitably results in accidental oil spills. The safety and preventive measures introduced internationally and nationally were able to reduce the number of spills and amount of accidental releases to the sea in the past decades. However, recent incidents show that marine oil spills are unpredictable events that may cause significant damage to the environment, wildlife and coastal communities. This dissertation is a study of the status of oil spill contingency management in the South Asian region. A comprehensive analysis of factors, which contribute to oil spill risks of each country, is investigated. Measures taken to reduce and control oil pollution risks are examined especially existing oil spill preparedness measures and the legislative arrangements in each country to reduce, and control accidental oil pollution were taken into account when analyzing the oil spill control mechanisms in each country in the region. The oil spill response capabilities of the regional countries are comparatively examined, using three main standard practices taking into account oil spill contingency practices; oil spill response equipment and support resources; and legislation and regulations adopted by each country. The exposure and preparedness index is used to examine the level of oil spill preparedness with comparison to oil pollution exposure of the country. Oil spill exposure and oil pollution preparedness levels are measured using parameters which give numerical values for oil spill exposure and oil pollution preparedness. The existing sustainable funding mechanisms for preparedness of oil spills are reviewed critically analyzing positive and negative points of available funding methods with a view to identify sustainable funding mechanisms for South Asian countries. The dissertation critically analyzes existing oil spill response capabilities of the countries and recommends a number of measures to improve oil spill combat capability in the South Asian regional countries.

Authors

M. Arabani  1  H. Haghsheno  2
1 Professor, Department of Civil Engineering, Faculty of Engineering, University of Guilan, Rasht, Iran.

2 Ph.D., Department of Civil Engineering, Faculty of Engineering, University of Guilan, Rasht, Iran.

10.24200/j30.2024.63856.3291
Abstract

Soil pollution by oil and its derivatives is a highly controversial environmental problem that also causes geological and geotechnical harm. The effect of oil pollutant type on geotechnical characteristics, especially soil compressibility, is an interesting topic neglected in previous studies, which needs further investigation. The research results on this topic can be used in the compressibility analysis of structures built on soils likely to be contaminated with oil pollutants. Using a one-dimensional consolidation test, this study evaluated the compressibility properties of clayey sand contaminated with 3, 6, and 9% (dry weight of the soil) of four oil pollutants: used motor oil, crude oil, diesel, and kerosene. Scanning electron microscopy (SEM) was also employed to assess the microstructural interaction between the soil and the four oil pollutants. In addition to the low dielectric constant of oil pollutants, their high viscosity played a crucial role in altering the compressibility properties of clayey sand. The SEM micrographs confirmed that oil pollutants change the soil structure into a flocculated but dispersed one. The higher the viscosity of the oil pollutant, the larger the formed clots. Besides increasing the pore space between particles and facilitating water movement by covering the soil particles, oil pollutants reduced the soil's specific surface area (SSA) and water absorption by the soil particles. This caused the water to drain faster, ultimately increasing the compaction coefficient (CC), consolidation settlement, consolidation coefficient (CV), and permeability coefficient (k). The higher the viscosity of the oil contaminant, the higher the surface energy at the oil-water interface, which decreases water drainage. The highest compressibility belonged to the samples contaminated with kerosene, followed by those infected with diesel, crude oil, and used motor oil. Thus, special attention should be paid to settling clayey sand contaminated with kerosene in geotechnical plans.
Keywords

Oil-polluted soil  Compressibility properties  Viscosity  Clayey sand

South Sudan is endowed with enormous petroleum resource (oil and gas) situated in Greater Bahr el Ghazal and Upper Nile Regions. Exploration Production Sharing Agreements (EPSAs) were signed between the Government of the Republic of South Sudan and the foreign contractors in July 2011, immediately after South Sudan attained her independence from the Sudan. Yet, with enormous oil and gas production, South Sudan has not realized any level of development and stability. Besides, oil companies have failed to adhere to the Petroleum Act 2012, Petroleum Revenue Management Act 2013 and Environmental Protection Regulations, leading to environmental degradation of oil-producing states. The paper used field interviews and secondary sources in tapping reality of petroleum resource curse in South Sudan. It combines case study, constructivist and process tracing methods to contextualize and validate causal chains and empirical casual processes. The key finding is that petroleum resource curse is ...

Background: The issue of environmental insurance has been raised since the early 1990s and has undergone extensive changes until today. The purpose of this research is to design a model for determining environmental insurance premiums related to maritime losses and pollution resulting from the oil and gas industry. Methods: This study is applied and employs survey methodologies as well as expert panels. In order to analyze the data, SPSS 22 and Expert Choice 11 software were used while hierarchical analysis was used to prioritize the components of the model. The final model was designed based on the Environmental Failure Mode and Effects Analysis method (EFMEA), and its goodness of fit was determined through conformity factor analysis. Results: The research identified six categories of activities and four major types of accidents associated with the oil and gas industry. Moreover, five environmental aspects were determined. Fire and explosions in facilities, pipelines, and tanks (0.886), Pipeline breakage or corrosion (0.714), Maritime accidents and vessel collisions (0.656), and Operational disruptions in facilities (0.631) were prioritized respectively. The calculated Root Mean Square Error of Approximation (RMSEA) index was 0.068, indicating that the proposed model demonstrates an adequate fit. Conclusion: Environmental pollution risks could be covered by commercial insurance by relying on international law within domestic, regional, or global insurance policies in compliance with the principles governing such policies.

As an archipelago, the Philippines is heavily engaged in domestic and foreign shipping activities which makes it highly vulnerable to oil pollution. It is the purpose of this present paper to make a follow-up review of the oil spill situation in the Philippines which provides analysis and evaluation of aquatic oil spills in the past 22 years. Results showed that the frequency and volume of oil spills generally occur in areas with high maritime traffic and experienced short-term decreases on periods affected by economic recessions. The sources and causes of oil spills are discussed while examining the possible influences of the changing climate. While, these had been identified, there is a gap in the incident reporting of oil spills. It is recommended that data records on oil spill incidents in the Philippines be systematic, consistent and comprehensively entail information not limited to date, locality, source, cause, and spillage amount.

Water deficit stress limits agriculture crop production. Plant growth-promoting rhizobacteria (PGPR) play an important role in control of water deficit stress. Today, for improving of plant tolerance to stress and the production of healthy crops, the application of biofertilizers, including growth-promoting bacteria, is interest. The present study investigates the effects of two different PGPRs (Pseudomonas fluorescens and Sinorhizobium meliloti) on some physiological and morphological characteristics in fenugreek under water deficit stress. For this purpose, a factorial design based on randomized complete block design with four water deficit levels (100%, 80%, 60% and 40% FC) and four PGPR condition as control, Sinorhizobium meliloti, Pseudomonas fluorescens and combination of S. meliloti. and P. fluorescens with three replications were carried out. Irrigation treatments were applied after flowering of plants until harvesting. The results showed that leaf area, shoot and root fresh and dry weight, phosphorus and potassium content, and water use efficiency (WUE) were significantly improved by PGPR inoculation and individual use of PGPR was more effective, whereas seed yield was decreased in PGPR treated plants.

In his study of modern English writers, A Sinking Island, Hugh Kenner argues that English literature, as we have known and loved it, no longer exists. "There is now a literature written out of English dictionaries that England either can't claim or doesn't know if it wants." 1 "English" literature has become the property of its former colonies, or, beginning with Joyce, those writers without countries, the modernists. It is tempting to blame Prime Minister Margaret Thatcher, Britain's censorious supernanny, for this loss of still another national resource. 2 However, England has long forgone its place as a literary center, even among those whom Winston Churchill, that cultural imperialist, called "the English-speaking peoples." What, then, is left of purely English literature? England, that Atlantis, rises to the surface of our minds most vividly in the words of its dead writers. The publication of Philip Larkin 's Collected Poems is an ...

Histopathological changes on the gills of the catfish, C. gariepinus (mean total length, 15.40+0.57 cm, mean weight, 22.08+2.51 g) exposed to light and heavy crude oils were studied in static toxicity bioassay over a 96-hour period after acclimation of test organisms in the laboratory. There was initial range finding tests to determine the concentrations of the toxicants to be administered on the test organisms in the definitive tests. The test organisms were exposed to five concentrations (1.0, 1.5, 2.0, 2.5 and 3.0%) of both toxicants and a control (0.0%) in static renewal bioassay. Histopathological changes on the gills of untreated fish showed normal parallel arranged gill filaments while lamellae of gill of exposed fish suffered different levels of damage including distension and fusion, and were also hypertrophic and necrotic. The control group had greater pH, temperature, and dissolved oxygen levels than the treated group. The greater concentration of accumulated polycyclic aromatic hydrocarbons (PAHs) in heavy crude oil may have contributed to the more degenerative alterations observed on the gills in comparison to light crude oil. Hence, a baseline toxicological study on the constituent and components of light and heavy crude oils is recommended so as to ascertain the level of PAHs in both oils.

Background: Over the years, the issue of environmental degradation of ecological resources from crude oil pollution and its human health impacts is receiving more global attention. The utilization of environmental models capable of predicting the fate, transport and toxicity of chemicals in spilled crude oil can provide essential knowledge required to deal with the complexity associated with the fate of volatile petroleum chemicals in the environment. Objective: This paper explores environmental fate of toxic volatile organics from oil spill in the Niger Delta Region of Nigeria. Methods: A critical analysis of available literatures/data from PubMed, Scopus, ResearchGate, Google Scholar, Jstor, including expert working group reports and environmental modeling using a screening tool (USEPA EPI Suite ™) was carried out to determine the environmental partitioning of Benzene, Toluene and Naphthalene (BTN) respectively. The organic-carbon partitioning coe cient (K oc) was computed as a function of soil-water distribution coe cient (K d) and percentage organic matter (%OM). This was utilized to determine the distribution of BTN in the environment and the possible risk posed on delicate ecological resources from crude oil pollution due to exploration and production activities within the Niger Delta Region (NDR), Nigeria. Results: Results from literature implicated sabotage and operational failures from pipelines as primary causes of crude oil spillages. Generation of a fugacity model using EPI Suite ™ revealed that the behavior of BTN is greatly in uenced by K oc values. The default Molecular Connectivity Index (MCI) showed that benzene and toluene will partition more into the water compartment while naphthalene will partition into the soil compartment. However, user-entered values showed all three chemicals partitioning more into the soil compartment. Aquatic toxicology estimation using Ecological Structural Activity Relationship (ECOSAR) revealed all chemicals not to be toxic even at overestimated K oc values. Conclusion: This research established the usefulness of screening level environmental modelling tools in assessing environmental risk and hence helpful in developing site-speci c models for monitoring chemicals in the environment which can assist governments, policy makers and industries in the design of appropriate regional disaster management plans.

Environmentally unfriendly Oil exploration activities have been ongoing in the Soku area of the Niger Delta of Nigeria since 1956. This study evaluated the concentration of hydrocarbons and heavy metals in Shellfish and drinking water sources in the study area. It revealed the absence (<0.001 mg/l) of most heavy metals (Ni, Ch, Cd, Pb mg/l) in the water column; a high concentration of the major ion composition of seawater (sulphates 5-1018; calcium 0.502-53.502; sodium 1.247-63.337; potassium 0.508-102.745; magnesium 0.354-42.574 mg/l); and high PAHs (<0.001-0.032 mg/l) levels occurring above WHO limits (0.007 mg/l) with some risk of exposure to cancer. Results from the analysis of shellfish showed that concentrations of chromium and zinc were below permissible limits while cadmium concentrations were slightly above permissible limits of the European Community. Nickel and lead were above permissible limits in the fish samples in all standards while PAHs occurred at the cancer risk levels of 10 −6. A review of the public health situation in the Soku area with a view to understanding current trends, sources of perturbations and preferable solutions to the potential public health challenges raised in this study is hereby recommended. Also, this study recommends that relevant agencies and developmental partners should launch a national drive to create awareness among people/environmental/public health professionals'/health workers/administrators on this regional concern.

Background:In Rivers State, Nigeria, Indigenous communities of Ebocha-Obrikom have nearly worst drinking water quality in the province with concerns extending from worsening water quality to deficiency of support from oil companies operating in the environment. The minute water is suspected, or recognized of being unsafe or hazardous to human consumption, community people are likely to be positioned under a wasted health.Objectives:To compare water quality parameters in the vicinity of Gas Flaring Area of Ebocha-Obrikom of Rivers State with that of the recommended standards.Methods:The research utilized standard analytical procedures. All sampling, conservation, transportation and analysis followed standard procedures described in APHA (2012). All the samples collected were transported to the laboratory through keeping in an icebox to prevent degradation of the organic substances.Results:Result depicts that Turbidity, DO, BOD, COD, TSS, Magnesium, Iron, Cadmium, Lead, Chromium, and ...

Tanzania is among the countries in the west of the Indian Ocean. The country is endowed with maritime resources and a considerable coastline of about 1500 Kilometers. The well being of people leaving along the coast depend on the use of resources of the ocean. The country is facing current and potential danger of marine oil pollution caused by ships calling its ports and terminals, ships using the West Indian Ocean route, land based activities, and the developments in offshore oil and gas activities in the country and within East Africa region. In order to achieve sustainable use of the oceans and its resource, this article provide a legal framework for marine oil pollution control in the context of prevention of oil pollution, response to marine pollution incident and compensation for oil pollution damage. Specifically, the article assesses national legislation in the light of international agreements. The article assists in the analysis of the established legal regime and institutional framework for purposes of improving the status of marine oil pollution control.

Over the years, the environmental degradation of ecological resources from crude oil pollution and its human health impacts is receiving more global attention. The utilization of environmental models capable of predicting the fate, transport, and toxicity of chemicals in spilt crude oil can provide essential knowledge required to deal with the complexity associated with the fate of volatile petroleum chemicals in the environment. This paper explores the environmental fate of toxic volatile organics from an oil spill in the Niger Delta Region of Nigeria. Results from the literature implicated sabotage and operational failures from pipelines as primary causes of crude oil spillages. The generation of a fugacity model using EPI Suite™ revealed that Koc values greatly influence the behavior of BTN. Benzene, Toluene, and Naphthalene (BTN) were partitioned into three compartments based on organic-carbon partitioning coefficient (Koc). The organic-carbon partitioning coefficient (Koc) was ...

The analysis of the 2002 Prestige tanker accident showed how public misinformation can worsen marine pollution incidents, rendering their management suboptimal as these evolve, thus raising the issue of appropriately informing and educating coastal and island populations who are at risk. Two decades later, developments in electronic platforms, including Geographic Information Systems (GIS), the Automatic Identification System (AIS) for ship signal transmission, and social media, provide a set of means for public monitoring of such incidents, creating the possibility to antagonise effectively erroneous or malevolent information, which can hinder efficient actions for containing marine pollution risks even without active training of the populations concerned. The authors, in the framework of the development of the Marine Coastal Observatory and Risk Management project “AEGIS+”, have developed E-S.A.V.E., an online innovative platform that (a) meets the needs of different users as reve...

Sri Lanka has frequently dealt with shipwrecks because it is geographically located at the center of international shipping lanes. The X-Press Pearl shipwreck caused to the territorial sea can be identified as irreversible damage. To protect the marine system, the Marine Pollution Prevention Act was enacted. Collision of ships, internal technical failures, human errors, or weather effects is multiple causes responsible for marine accidents and incidents. To do safe and clean operations in the maritime industry is the role of the human factor. This research includes the significant impact of the X-Press Pearl maritime disaster on Sri Lanka's sensitive coastal environment, local communities, and the economy, identifying hazards, risk assessment, Disaster management cycle. There is uncertainty in marine environmental risks because of the complex factors and fuzzy mechanisms. Therefore, a new assessment technique is proposed based on a weighted Bayesian network (BN). This paper aims to offer hazard identification and risk analysis system to minimize the impacts of shipping on the marine environment. Therefore, in the end, some recommendations are highlighted to implement to prevent similar events shortly.

Water deficit stress limits agriculture crop production. Plant growth-promoting rhizobacteria (PGPR) play an important role in control of water deficit stress. Today, for improving of plant tolerance to stress and the production of healthy crops, the application of biofertilizers, including growth-promoting bacteria, is interest. The present study investigates the effects of two different PGPRs (Pseudomonas fluorescens and Sinorhizobium meliloti) on some physiological and morphological characteristics in fenugreek under water deficit stress. For this purpose, a factorial design based on randomized complete block design with four water deficit levels (100%, 80%, 60% and 40% FC) and four PGPR condition as control, Sinorhizobium meliloti, Pseudomonas fluorescens and combination of S. meliloti. and P. fluorescens with three replications were carried out. Irrigation treatments were applied after flowering of plants until harvesting. The results showed that leaf area, shoot and root fresh and dry weight, phosphorus and potassium content, and water use efficiency (WUE) were significantly improved by PGPR inoculation and individual use of PGPR was more effective, whereas seed yield was decreased in PGPR treated plants.

Industrial and urban development are contributing to an increase in global environmental degradation. Therefore, the release of heavy metals from mining-related operations into surface water is harmful to human health. But as anthropogenic influences on the environment grow, surface water characteristics are also alter, impacting aquatic creatures. In order to analyze the acceptability of the surface water in the gold mining area for drinking and irrigation uses, different quality water assessment methodologies were incorporated in this research. In light of this, the purpose of the current study is to comprehend how the hydrogeochemistry and appropriateness of surface water for drinking and irrigation vary

The analysis of the 2002 Prestige tanker accident showed how public misinformation can worsen marine pollution incidents, rendering their management suboptimal as these evolve, thus raising the issue of appropriately informing and educating coastal and island populations who are at risk. Two decades later, developments in electronic platforms, including Geographic Information Systems (GIS), the Automatic Identification System (AIS) for ship signal transmission, and social media, provide a set of means for public monitoring of such incidents, creating the possibility to antagonise effectively erroneous or malevolent information, which can hinder efficient actions for containing marine pollution risks even without active training of the populations concerned. The authors, in the framework of the development of the Marine Coastal Observatory and Risk Management project “AEGIS+”, have developed E-S.A.V.E., an online innovative platform that (a) meets the needs of different users as reve...

A survey of soil arthropod fauna inhabiting Nigeria Institute for Oil Palm Research (NIFOR) was carried out from July-September 2012, with a view to determine the diversity and distribution of soil arthropods of the area. Two study stations were identified at the area, namely; Station one (Plantation site) and Station two (Control site). One thousand eight hundred and seventy-seven (1877) individual soil arthropods were recorded from both stations. These individuals were represented in 4 classes, 11 orders and 21 families which were collected and extracted using the pitfall trap method and the Berlese Tullgren Extractor Funnel. Data collected from the study stations were subjected to appropriate statistical analyses which included Simpson's index (Ds), the Shannon Wiener index (H'), the Shannon Diversity T-test and Evenness (E) to determine the diversity of the soil arthropod fauna. Station one (Plantation site), was the most diverse station (Ds=2.99) and (H'=1.84) while station two (Control site) having (Ds= 2.94) and (H'= 1.69) is the least diverse station which may be as a result of anthropogenic activities. The Order Hymenoptera and Family Formicidae (50.5%) and (38.7%) respectively were the dominant and abundant group in both stations with the Order Crustacea and Family Armadillidae (22.2%) and (1.63%) respectively were the least dominant and abundant in both stations. The soil arthropod fauna correlated positively with the soil organic carbon (r=0.16), soil moisture content (r= 0.26) and soil pH (r=0.60) while the soil temperature correlated negatively (r=-0.89) in both stations. This implies that soil arthropods increase with increasing soil moisture content and decreasing soil temperature. © JASEM 9 13

The last 20 years boast globalization at an unprecedented rate, with fewer people in poverty than ever before, increased life expectancy, and revolutionary advancements in technology, medicine, transportation, and climate science. International law has attempted to adapt to these changes, but the issues that affect the oceans are wide-ranging and difficult to address in the diplomatic arena. Therefore, in order to come to an understanding of the procedures (or lack thereof) regarding ocean issues, pollution (direct and indirect), commodification by oil industries, and aquaculture must be considered. These in particular have consequential impacts on human health. There are several instruments for regulating all the aforementioned, from international conventions to norms of the industries, to state regulations, private compensation funds, and bilateral/multilateral agreements. However, what is indisputable is that there is much yet to be developed when it comes to international maritime law as time goes on and global needs continue to shift.It is especially useful to understand the governing bodies concerned with international maritime law. The most major of these organizations is the International Maritime Organization (IMO), a specialized agency established by the United Nations. It is built around shipping regulation, and its strategic directions are as follows 1 : 1. Improve implementation. 2. Integrate new and advancing technologies in the regulatory framework.

Introduction
The world's population continues to grow, and agriculture must keep pace with increasing demand for food production. Many challenges threaten crop yields, such as herbivorous insects, plant pathogens and weeds, the occurrence or risk of each one often requires the use of pesticides. Despite the usefulness of pesticides in crop protection, their excessive and irrational use can endanger human health and the environment. On the other hand, the very costly application of chemical fertilizers, especially nitrogen, which is a key element in plant nutrition under insufficient soil fertility conditions, can cause groundwater pollution with nitrate and air pollution with nitrogen oxide (21). Although herbicides are intended to protect crops, they can potentially pose a threat to the activity of rhizobium that symbiosis with legumes, thereby reducing the nitrogen fixation of symbionts. If symbiotic nitrogen fixation is adversely affected, crop yield will subsequently be adversely affected (6). All previous studies on the effect of herbicides on crop-rhizobium symbiosis under a certain soil pH have been evaluated. Therefore, it is important to understand the interaction between soil pH and the toxicity severity of herbicides on crop-rhizobium symbiosis, because soil acidification or alkalization (4) can occur over several years in intensive agricultural ecosystems. Therefore, this study aimed to investigate whether the severity of herbicide toxicity on crop-rhizobium symbiosis in different soil pH conditions can be attributed to variations in the electrical charge properties of herbicides. Based on this hypothesis, three herbicides were selected: ethalfluralin, a non-ionic herbicide, imazethapyr, an acidic herbicide, and metribuzin, a basic herbicide (23). The objective was to examine their toxicity on soybean-rhizobium symbiosis under three soil pH levels.
Materials and Methods
The soil required for this experiment was prepared from the educational farm of Bu-Ali Sina University of Hamedan, which had a pH of 7.2. This soil is considered as natural soil. Based on a pre-test results on natural soil, adding and mixing 0.2 g sulfur and 5.5 g lime with each kg natural soil could create artificial soils with pH of 6.4 and 8, respectively. The pot experiment was performed in a completely randomized factorial design under open-air conditions. Herbicidal factor included control, pre-planting application of 990 g ethalfluralin ha-1, post-planting application of 450 g metribuzin ha-1and post-emergence application of 108 g imazethapyr ha-1. Soil pH factor was 6.4, 7.2 and 8. Soybean seeds (cv. Hobbit) were disinfected with 1% sodium hypochlorite for five min and washed and dried with water. They were then immersed in commercial soybean inoculum (BiosoyTM) for five min and dried again. Inside each pot, four seeds inoculated with bacteria were planted at two cm depth. Separately, an inoculated seed treatment under natural soil conditions without herbicide application was considered to investigate the effects of seed inoculation. Growth parameters including height, dry weight of stem and root, number and dry weight of nodes formed on root, the nitrogen content of stems and roots were measured and analyzed statistically using SAS software. The means were compared with the LSD test at the level of 5% probability.
Results and Discussion
In comparing the two treatments of seed inoculation and non-inoculation with a commercial soybean inoculum and their cultivation in natural soil, it was found that seed inoculation had a significant positive impact on various growth parameters. Specifically, it led to increased plant height, dry weight of shoots and roots, as well as nitrogen content in both shoots and roots. Additionally, there was a notable decrease in the shoot-to-root dry weight ratio. Previous studies have also reported similar results, indicating changes in the photosynthetic response pattern due to bacterial seed inoculation in different soybean genotypes (16). In treatments where no herbicide was used (control), soybean nodulation and certain growth parameters were significantly influenced by soil pH. The highest level of nodulation was observed at soil pH values of 7.2 and 8.The lowest number of nodes (21.3 node plant-1) and the lowest dry weight of nodes (491.8 mg plant-1) were also observed in soil with a pH of 6.4. Poor nodulation observed at acidic soil pH may be associated with hydrogen ion toxicity, which may prevent the onset of nodulation, as reported in previous studies (3). The results showed that the toxicity severity of imazethapyr and metribuzin on nodulation (number and dry weight of nodules) depended on soil pH. As the pH of the soil increased, the toxicity of imazethapyr decreased, but the toxicity of metribuzin increased. While the toxicity severity of ethalfluralin on nodulation was not affected by soil pH.
Conclusion
Despite the advantages of herbicide application, it can have negative effects on soybean-rhizobium symbiosis, limiting the capacity of rhizobium for nitrogen fixation. Consequently, the reliance on chemical fertilizers increases to meet the nutritional needs of soybeans. Additionally, in acidic soils where herbicides are less absorbed by soil particles, further disruption of the soybean-rhizobium symbiosis can occur. Our experiment revealed that the use of metribuzin in alkaline pH soil or imazethapyr in acidic pH soil can cause severe damage to the soybean-rhizobium symbiosis. As soil acidity or alkalinity can change rapidly in agricultural ecosystems due to conventional farming practices such as lime or sulfur addition to adjust soil pH, it is crucial for farmers to consider the electrical charge of herbicides and the pH of their soil. This awareness can help minimize the herbicide toxicity on soybean-rhizobium symbiosis.

Over the years, the environmental degradation of ecological resources from crude oil pollution and its human health impacts is receiving more global attention. The utilization of environmental models capable of predicting the fate, transport, and toxicity of chemicals in spilt crude oil can provide essential knowledge required to deal with the complexity associated with the fate of volatile petroleum chemicals in the environment. This paper explores the environmental fate of toxic volatile organics from an oil spill in the Niger Delta Region of Nigeria. Results from the literature implicated sabotage and operational failures from pipelines as primary causes of crude oil spillages. The generation of a fugacity model using EPI Suite™ revealed that Koc values greatly influence the behavior of BTN. Benzene, Toluene, and Naphthalene (BTN) were partitioned into three compartments based on organic-carbon partitioning coefficient (Koc). The organic-carbon partitioning coefficient (Koc) was computed as a function of soil-water distribution coefficient (Kd) and percentage organic matter (%OM). Koc was used to determining the possible risk posed on delicate ecological resources. Aquatic toxicology estimation using Ecological Structural Activity Relationship revealed that all chemicals were not toxic even at overestimated Koc values. This research established the usefulness of screening level environmental modeling tools in assessing ecological risk and hence helpful in developing site-specific models for monitoring chemicals in the environment, which can assist governments, policymakers, and industries in designing appropriate regional disaster management plans.

A site that covers over 20 acres of coastal saline depression in the western Mediterranean coastal desert of Egypt (El-Hamra station, the main crude oil pipeline terminal in Alamein) is contaminated with petroleum. This area, prior to contamination by crude oil was dominated by different common halophytes. Atriplex halimus (L) and Arthrocnemum macrostachyum (Moric.) are now the most dominant species growing in this site. These species adapt themselves through different growth parameters, physiological and biochemical changes. Crude oil affects significantly on soil fertility and increasing pH (8.4). Importance value (IV), height and canopy diameter of the two studied species exhibited an increase in the polluted site. Organic metabolites such as fatty acids, antioxidant compounds and protein fractions in shoots of studied species which collected from the oil-contaminated and noncontaminated sites were examined. Fatty acid fractions exhibited the opposite performance especially the content of saturated C: 16 (palmitic), mono and di-unsaturated C18:1 (oleic) and C18:2 (linoleic) fatty acids as well as poly-unsaturated C18: 3 and C20: 3 (Omega-3 fatty acids). Antioxidant activity and most examined phenolic compounds were increased in A. macrostachyum which grow in a contaminated site. Protein fractions in A.halimus attained with enormous variations therefore, a Genomic Templet Stability (GTS %) was lower than in A. macrostachyum under contamination. The biochemical and behavioral responses to oil pollution varied with the two different species may be according to the genetic make-up of individuals, which make the two studied species useful and effective tools for phytoremediation purposes.

The paper conducted a critical evaluation of South Sudan’s policy framework for health and safety management in the oil and gas industry in Paloich- Melut County with interests in Dar Petroleum Operating Company. Specifically, the study assessed the effect of government policy, the organizational practices that affects the health and safety management of community and to explore the challenges affecting the implementation of policy frameworks for health and safety management practices by Dar Petroleum Operating Company. Descriptive survey research design was used to collect quantitative and qualitative data thus following mixed method approach. Quantitative data was collected using questionnaires while Qualitative data was obtained from in-depth interviews. Quantitative data was analyzed using descriptive and inferential statistics. Qualitative data was analyzed using thematic analysis. The results revealed that government policy and organizational practices are positively and signi...

Pollution caused by crude oil is one of the most prevalent environmental problems in oil-rich countries. Bioremediation processes usually exploit the ability of microorganisms to degrade and/or detoxify organic contaminants. A widely used bioremediation strategy is bio-stimulation of the soil’s indigenous microbes by the addition of nutrients, as crude oil contamination tends to result in the rapid depletion of the available pools of major inorganic nutrients such as nitrogen and phosphorus. This study examined the bio-stimulation effect of diammonium phosphate and urea fertilizers on crude oil-contaminated soil enzymes. Soils were artificially contaminated with 3000, 5000, or 8000 ppm of crude oil and treated with Diammonium phosphate (DAP) and urea fertilizers. The activities of soil enzymes such as laccase, lipase, catalase, and peroxidase were analyzed every 6th day for 30 days. The results indicated that the activity of laccase for all the treated soils was significantly higher than the untreated group on days 18, 24, and 30, while those of peroxidase and catalase peaked at day 12, with a sharp decline on days 18 to 30 when compared to the untreated soil. However, the activity of lipase continued to increase until the 30th day in all the treated soils, and the increase was higher in contaminated soils treated with DAP and urea. The decreased activities of peroxidase and catalase in the treated soils may be related to a decrease in the microbial load of the soil. Furthermore, the increase in the activities of soil enzymes, especially in the treated soils, suggested that the treatments contributed to enhancing the activities of the enzymes, and hence may help in the bioremediation process through bio-stimulation of the soil enzymes that function in the breakdown of environmental contaminants.

In this research, the effect of plant growth-promoting rhizobacteria, Bacillus pumilus, and Zhihengliuella halotolerans, on the morpho-physiological traits of Nitraria schoberi under the influence of dust (control and 1.5 g/m2/month) was investigated. The results showed that dust had a negative effect on the morphological and physiological traits of the plant. Dust caused a decrease of 20, 15, 17 and 20% in chlorophyll a, carotenoid, total soluble protein, and total dry biomass and an increase in the total flavonoids, total phenol content, total antioxidant capacity and glycine betaine amounting to 107, 32, 15 and 10 percents, respectively. Both bacteria improved the condition of the plant against stress, so that B. pumilus and Z. halotolerans increased the amount of chlorophyll b by 13 and 21%, protein by 27 and 43%, and total biomass by 60 and 27%, respectively. In this experiment, the role of B. pumilus strain was more than that of Z. halotolerans strain, so that B. pumilus strain alone had the greatest effect in increasing chlorophyll a and seedling quality index by 52 and 108%, respectively. The results showed that B. pumilus and Z. halotolerans strains can increase the resistance of the Nitraria schoberi to dust stress and help us to stabilize salty dusts in playas.

The Proterozoic basement is a potential host for uranium mineralization and therefore the probability of occurrence of uranium is highly likely in the Dhofar region of southern Oman. The crystalline basement of the Salalah area (Dhofar, Sultanate of Oman) is the largest area of Proterozoic basement of the Arabian-Nubian Shield which outcrop in Oman. It is because, the most productive parts of the crust for uranium exploration and production in the world are in similarly aged i,e Proterozoic rocks. Further, the area is heavily faulted and some of these faults have already been identified as the place of uranium enrichment. Also, the fault systems must have acted as fluid conduits for circulating waters scooping up uranium from deeper formations and carrying it to higher levels along the fault plane and also distributing it near the surface. Random sampling of gamma ray spectroscopy has revealed a concentration of uranium as much as 30-35 ppm which was substantiated by XRF analysis near the study area. And therefore, the interest lies in investigating the uranium mineralized subsurface structuers. Accordingly, total magnetic fields along eleven traverses were recorded at an approximate line interval of 20 m with a measurement interval of 10 m in the study area close to Yemen border. The acquired data was subjected to regional residual separation to decipher low frequency signals related to deep anomalies and also residual component to depict high frequency shallow seated small features. The computed amplitude of analytical signal indicates the precise spatial location of subsurface sources. Further, estimated depth to source based on Euler deconvolution (ED) and Fourier spectral analysis are found to be in the range of < 15m-> 60 m. The salient features of the analysis highlighting the outcome are presented.

یونجه ( Medicago sativa L. ) یکی از مهم ترین لگوم های علوفه ای است که بیش از 600 هزار هکتار از اراضی زراعی کشور را به خود اختصاص داده است. این گیاه قادر است در صورت وجود باکتری Sinorhizobium meliloti در خاک و مناسب بودن شرایط اقلیم و خاک، مقدار قابل ملاحظه ای از نیتروژن مولکولی هوا را تثبیت نماید. تعداد 20 نمونه خاک از مناطق مختلف کرج نمونه برداری شد و برخی خصوصیات فیزیکی و شیمیایی  نمونه ها اندازه گیری شد. سپس با کاشت بذر یونجه در شرایط گلخانه ای، تعداد32 جدایه باکتری جداسازی و تعداد 20 جدایه منسوب به S. meliloti شناسایی گردید و با استفاده از آزمون آلودگی، تشخیص جدایه ها تأیید شد. برای بررسی تأثیر 20 جدایه S. meliloti بر عملکرد یونجه و مقایسه آن با مصرف کود نیتروژنی در حضور باکتری های S. meliloti آزمایشی در قالب یک طرح کاملا تصادفی شامل فاکتورهای تلقیح (شامل تیمار بدون تلقیح یا شاهد، تیمار تلقیح با باکتری، تیمار کود نیتروژنی) در سه تکرار در مجموع 72 تیمار انجام شد. نتایج تجزیه خاک ها نشان داد که مقدار فسفر، بور، آهن و روی در اکثر مزارع یونجه کمتر از حد بحرانی بود و کمبود این عناصر ...

Introduction: Increase in the incidence of contagious diseases emphasizes the importance of microbial contamination of dental materials. The purpose of this in vitro study was to determine microbial contamination of different consumable dental materials for the presence of viable microorganisms. Materials & Methods: In this study, 19 consumable dental materials were surveyed for microbial contamination. These materials included: three kinds of gutta percha, paper cones, gingival retraction cords, alginates, wooden wedges, two kinds of prophylaxis pastes, and one kind of dental dressing and zinc oxide powder. From each material, three brands and from each brand three samples were obtained. Solid and liquid specimens were cultured on Tryptic Soy Broth, Thioglycolate and Sabouraud Dextrose Agar and all of the cultured media were stained by gram method. Data were analyzed by SPSS-16 software using descriptive and analytical (Fisher&#39;s exact and Chi-Square) tests. The level of signifi...

Groundwater is a valuable natural resource whose quality is threatened by natural and man-made pollutants. This study aims to perform a hydrochemical characterization of groundwater resources used for domestic and irrigational activities in Melong (Littoral Cameroon). Thus, 26 subsurface water samples were collected in the dry season (six sampling points) and rainy season (seven sampling points) of the years 2019 and 2020. Physical water quality parameters were measured on the field while ionic constituents and bacteriological parameters were determined in the laboratory. The main findings revealed that the pH of the water samples was slightly acidic to neutral, fluctuating from 5.3 to 7.1; electrical conductivity ranged from 0.03 to 0.33 µS/cm and turbidity varied from 0.5 to 33.7 NTU revealing that the water is weakly mineralized. The ionic constituents were such that Ca 2+ > K + > Mg 2+ > Na + for cationic constituents while anions appeared as HCO 3-> NO 3->Cl-> PO 4 3-. The major ions fell within the acceptable limits of World Health Organisation (WHO) drinking water standards. Bacteria indicators of faecal pollution were identified in all the water samples, including Enterobacteria, Escherichia coli, Streptococcus, Salmonella, Shigella, Staphylococcus and Vibrio. This indicates an exposure of water sources to unhygienic conditions that may place consumers at risk of water-borne diseases, hence necessitating basic treatment of the water before consumption.

The effect of spent lubricating oil on the composition and abundance of soil arthropods in impacted sites compared with natural control sites was assessed in Benin City, Southern Nigeria. The Modified Berlese-Tullgren Funnel method was used for the extraction of soil arthropod fauna. The results showed that altogether, 476 specimens were collected and sorted into four arthropod groups, namely Acarina, Collembola, Hymenoptera and Myriapoda in successive order of abundance at both sites studied. Soil arthropod taxa and abundance were significantly lower (u (2) = 51, P<0.05) at the impacted sites where 10.92% (52) of the total number occurred compared to 89.08% (424) recorded in the natural control site. Significant differences were detected in pH and total hydrocarbon content (THC) between the impacted and control sites, the values of pH and THC were significantly higher (P<0.05) at the impacted site; inversely, the arthropod faunal abundance were lower at the impacted sites. Basically, Myriapoda were most sensitive while Acarina, Collembola and Hymenoptera showed trends of population fluctuation. In general, abundance and richness of species were negatively affected by habitat transformation caused by spent engine oil application. © JASEM

A radish species was grown in a sandy loamy soil either unpolluted or polluted by increasing concentrations of crude oil added to watering solutions during one month under controlled laboratory conditions. This procedure was set to evaluate the impact of oil pollution of the substrate on the elemental uptake by plants. In summary, the increasing pollution by crude oil to the soil has not a univocal impact: the changing elemental contents in the roots and leaves of the cultivated radishes are never single trended with the amount of oil pollution, showing in turn that they are not provided by the spilled oil. The most significant elemental increase occurs in the leaves of the radishes grown in the soil polluted by 10 ml of oil and in the roots of those grown in the soil polluted by 4 ml of oil. In the detail, the significant effects of the oil pollution induce in the leaves: (1) similar behaviors for Ca, K, P, Mg, Fe and Al; (2) the highest impact on Ca, K, P, Mg and Al at the intermediate 10-ml pollution; (3) the highest uptake at the high side of pollution for Fe, Mn, Zn, Ni, Co, Cr and Pb; and (4) no significant impact on the uptake of the REEs. Oil pollution on the plant roots impacts: (1) an increased Ca, Fe, Al and Si uptake, often only in the case of the highest pollution, while P's uptake decreases; (2) an increase of the microbial population by a factor of about 2.5 at low pollution and a dramatic decrease at higher pollution; (3) an uptake of REEs only at the highest degree of pollution by a specific increase of the light REEs. The translocation roots-to-leaves indicates a decrease of Ca to the leaves when oil pollution increases, while remaining state for K and P with a slight decrease when pollution is at its maximum. The total biomass increases in the soil at low levels of pollution, decreases at intermediate levels and remains the same at high levels of pollution. The increase of most of elements at low level of oil supply is correlated with an increase in microorganism density, which suggests that availability of elements in soil can be attributed to an increase in organic activity, which has been stimulated by the oil pollution.

A survey of soil arthropod fauna inhabiting Nigeria Institute for Oil Palm Research (NIFOR) was carried out from July-September 2012, with a view to determine the diversity and distribution of soil arthropods of the area. Two study stations were identified at the area, namely; Station one (Plantation site) and Station two (Control site). One thousand eight hundred and seventy-seven (1877) individual soil arthropods were recorded from both stations. These individuals were represented in 4 classes, 11 orders and 21 families which were collected and extracted using the pitfall trap method and the Berlese Tullgren Extractor Funnel. Data collected from the study stations were subjected to appropriate statistical analyses which included Simpson's index (Ds), the Shannon Wiener index (H'), the Shannon Diversity T-test and Evenness (E) to determine the diversity of the soil arthropod fauna. Station one (Plantation site), was the most diverse station (Ds=2.99) and (H'=1.84) while station two (Control site) having (Ds= 2.94) and (H'= 1.69) is the least diverse station which may be as a result of anthropogenic activities. The Order Hymenoptera and Family Formicidae (50.5%) and (38.7%) respectively were the dominant and abundant group in both stations with the Order Crustacea and Family Armadillidae (22.2%) and (1.63%) respectively were the least dominant and abundant in both stations. The soil arthropod fauna correlated positively with the soil organic carbon (r=0.16), soil moisture content (r= 0.26) and soil pH (r=0.60) while the soil temperature correlated negatively (r=-0.89) in both stations. This implies that soil arthropods increase with increasing soil moisture content and decreasing soil temperature. © JASEM 9 13

Soil physicochemical properties (pH, electrical conductivity (EC), % moisture, total organic carbon (TOC), total organic matter (TOM)), total extractable hydrocarbon content (THC), and micronutrient (Mn, Fe, Cu, Zn) levels of the Mgbede-20 oil-impacted site in Niger Delta, Nigeria, were investigated. Both oil-impacted and their background control soils were found to be acidic especially at surface depth. A slightly higher EC value of 107.4 AE 15.0 mS cm À 1 was obtained for the subsurface-polluted soils. Of the micronutrients investigated, only Fe exceeded its acceptable limit (> 100 mg/kg). The observed increase in moisture content resulting from the oils aggregation of soil particles may lower soil porosity, and increase resistance to penetration and hydrophobicity. Soil pH can be adjusted by aeration to complete the microbially mediated oxidation of the organic acids, followed by the addition of agricultural lime to provide some buffering capacity to the soil.

I am especially indebted to the officers and organizations in five maritime nations in the South Asian region that shared their knowledge, expertise and information through the interviews and questionnaires. I also take this opportunity to extend my special thanks to Mr. Chris Hoebeke and all the library staff for their assistance finding research materials from various libraries. Many thanks also to PhD student Mr. Jonas Palsson, who guided and supported me during this research study. My thanks are also due to all colleagues of the class, specially, Idrees, Shimla, Gopal, Uddin, and Rahaman, Danny and Moe for their assistance and encouragement. Lastly, I express my profound gratitude to my parents for their unbounded love, blessings and scarifies. Also, I would like to express my very special thanks to my wife, Maddo for her encouragement and patience during my studies.

The produced water that is in Mujama is a time bomb. What if it rains, and the whole area floods? All the water will burst and flow into the river and it will kill everyone here in Melut and Adar." Traditional Leader in Melut. Summary While South Sudan is endowed with 3.5 billion barrels of proven oil reserves, the exploitation of this natural wealth is turning into a catastrophe for some local communities, particularly in Melut County. Through focus group discussions, individual interviews, and field observations, we found the following: 1. Many households in Paloch, Melut County, are in close proximity to oil wells and facilities, and within a short distance of a large lake of toxic produced water, exposing them to highly toxic chemicals. 2. Livestock graze around the oilfields, passing on highly toxic pollutants to residents through the food chain. 3. Community drinking water, held in containers that are placed on dusty roadsides by Dar Petroleum Operating Company (DPOC), and chemical containers used by community members to hold water, are likely sources of human exposure to toxic contaminants. 4. Communities have repeatedly complained about a high prevalence of petroleum pollution that causes diseases and reproductive health issues, including birth defects, infertility, stillbirth, and miscarriages, among others. We discovered 13 cases of © The Sudd Institute || Policy Brief | 2 birth defects, including spinal bifida, facial and head deformities, sexual organ deformities, limb deformities, and growth retardations. 5. All of the participants expressed anger and frustration, a sign of a more serious potential crisis that could cripple petroleum industry operations in the area, if not prioritized and addressed. We recommend the following to the Revitalized Transitional Government of National Unity (RTGONU) and DPOC: 1. Urgently identify areas sufficiently distanced from the oil fields, build basic services infrastructure in those areas, and relocate residents away from the oil fields and facilities; 2. Fence off the oilfields to prevent access by humans, livestock, and wildlife; 3. Conduct a comprehensive environmental and social assessment similar to the one that has been conducted in Ogoniland in Nigeria by the United Nations Environment Programme (UNEP) to assess the extent of pollution damage, determine compensation and remediation costs, and make recommendations that are enforceable through an act of parliament or a presidential order; and 4. Expedite the tabling, review, and passage of the draft Environmental Protection and Management Bill to strengthen environmental protection rules and enforcement capacity to better protect the health and welfare of those South Sudanese suffering from oil industry operations.

The availability of iron for roots has been demonstrated as a critical factor in plant production. The addition of synthetic iron chelates to soil is a common practice in agriculture, which is not economically beneficial. Besides, chemical iron fertilizers cause many problems such as food contamination and environmental pollution. Development of natural Ferrioxamine B as an efficient and safe iron source may be the best strategy to overcome plant iron deficiency and prevention of synthetic agent pollution. The present study investigates the ability of a hydroxamate type siderophores

The use of natural dyes in foods enhances the quality, efficiency and sensory properties of the product and also, they are associated with anti-inflammatory and anti-cancer effects and therefore they play an important role in human health. Chlorophyll is used as a natural pigment in a variety of foods. The aim of this study was extraction of chlorophyll from Persian clover (Trifolium resupinatum L.) using enzyme method and evaluation its antioxidant and antibacterial properties. Antioxidant activity of chlorophyll extracted from Persian clover was performed by three methods including DPPH and ABTS free radicals scavenging and ferric reducing antioxidant power (FRAP) and antibacterial effects against different microorganisms was also carried out using agar disk diffusion and microdilution (MIC and MBC) methods. The results showed that the concentration of chlorophyll a was almost twice of chlorophyll b and higher concentrations of chlorophyll had higher antioxidant activity in DPPH and ABTS free radicals scavenging and FRAP (p>0.05). Antibacterial effects of chlorophyll at concentrations of 20, 40, 60 and 100 μM were different, with bacterial resistance in Pseudomonas aeruginosa > Salmonella typhi > Escherichia coli > Staphylococcus aureus > Listeria monocytogenes (P<0.05) in agar disk diffusion and Pseudomonas aeruginosa > Salmonella typhi > Escherichia coli > Staphylococcus aureus = Listeria monocytogenes in microdilution respectively. Based on the results and the antioxidant and antibacterial effects of chlorophyll at higher concentrations, it can be used as a biocolorant in food and pharmaceuticals. However, further tests are needed to obtain further results.

eventually results in accidental oil spills. Introduction of preventive measures with the safety concerns internationally recent incidents in this concerns show that marine oil spills are unpredictable events that may cause significant damage not only to the marine ecosystems and wildlife, but the coastal communities and nationally were able to reduce the potential effects of spills and amount of accidental releases into the sea in the past decades. However, in large.  This dissertation is study of the impact of oil spills in the marine environment comprehensive analysis of related factors, which contribute to oil spill risks and the Measures taken in this event to reduce and control oil pollution risks are examined especially with the existing o

Background: Soils have a key role in establishment and growth of biota and also are as a natural resource, national capital and life substrate in any country. Therefore, every contamination can be transferred from soils to higher food levels with its negative impacts. Therefore, the purpose of the present study is to investigate oil pollution in soils caused by the establishment of Shahid Tondgovian Oil Storage in Zanjan province. The depot has three storage tanks with capacity of 47, 35 and 26 million liters of oil and gasoline and kerosene, respectively. Methods: Soil samples were collected from a depth of 5-15 cm at 20 sites and the values of EC, pH and PAHs were measured. Then T-test was used to compare the results with standards and control sites. Results: The mean of pH and EC results were 8.24 and 281 µ/cm, respectively. The results showed PAHs values were lower than the standard and there was no statistically significant difference between the study sites and the control one (P > 0.05). Also, the amount of benzo (a) pyrene compound, used as an indicator of total PAHs to study carcinogenic effects, was lower than standard in study area. Therefore, there is no health risk for the oil residents in collected samples from Shahid Tondgoian Oil Storage. Conclusion: Currently, oil pollution is not observed in the soils around the study area and there is no health risk for the residents in the suburbs.

Investigations were undertaken at 4 habitat-types (unpolluted, oil-polluted 1year, 3 and 6 years pre-study) in a secondary rainforest, Nigeria, to determine trends in the natural recovery of soil micro-arthropods (mites and Collembolan) in the polluted habitats. Soil samples were taken monthly with an 8.5cm-diameter bucket-type auger over a 2yr-period (May, 2007-April, 2009). Extraction was by the Berlese-Tullgren funnel. Identification was conducted with the aid of standard keys and comparisons of unidentified species with type specimens. Mean Total Hydrocarbon (THC) values were 10mg/kg (undisturbed) 630mg/kg (polluted 1 year pre-study) 260mg/kg (polluted 3 years pre-study) and 125mg/kg (polluted 6years pre-study) habitats. In all habitat-types, Cryptostigmata (Oribatida) were the most abundant mites. Three of the 11 Oribatid species were absent from the habitat polluted, 1-year pre-study but re-colonized the habitat polluted 3 years pre-study, while 4 of the 5 Mesostigmata species re-colonized this habitat. In the habitat polluted 6years pre-study, two more Oribatid species and the Mesostigmata Prodinichidae species re-colonized this habitat. In contrast, approximately 8 years after the oil spill, 5 Oribatid species and the Mesostigmata, Uropopidae spp never recovered. The Collembolan sp Hypogastina, absent from the habitat, polluted 1 year pre-study, re-colonized the habitat, polluted 3 years pre-study. There were significant positive correlations between total mite and collembolan densities and the length of the intervening periods between occurrence of spill and commencement of the study. (F cal =4.63; F tab =3.62; P< 0.05; F cal =7.80; F tab =3.62; P<0.05). The implications of these results in the bio-monitoring of oil-polluted habitats are discussed.

This study presents the proof-of-concept of the "Oil-Spill Snorkel": a novel bioelectrochemical approach to stimulate the oxidative biodegradation of petroleum hydrocarbons in sediments. The "Oil-Spill Snorkel" consists of a single conductive material (the snorkel) positioned suitably to create an electrochemical connection between the anoxic zone (the contaminated sediment) and the oxic zone (the overlying O 2-containing water). The segment of the electrode buried within the sediment plays a role of anode, accepting electrons deriving from the oxidation of contaminants. Electrons flow through the snorkel up to the part exposed to the aerobic environment (the cathode), where they reduce oxygen to form water. Here we report the results of lab-scale microcosms setup with marine sediments and spiked with crude oil. Microcosms containing one or three graphite snorkels and controls (snorkel-free and autoclaved) were monitored for over 400 days. Collectively, the results of this study confirmed that the snorkels accelerate oxidative reactions taking place within the sediment, as documented by a significant 1.7-fold increase (p = 0.023, two-tailed t-test) in the cumulative oxygen uptake and 1.4-fold increase (p = 0.040) in the cumulative CO 2 evolution in the microcosms containing three snorkels compared to snorkel-free controls. Accordingly, the initial rate of total petroleum hydrocarbons (TPH) degradation was also substantially enhanced. Indeed, while after 200 days of incubation a negligible degradation of TPH was noticed in snorkel-free controls, a significant reduction of 12 ± 1% (p = 0.004) and 21 ± 1% (p = 0.001) was observed in microcosms containing one and three snorkels, respectively. Although, the "Oil-Spill Snorkel" potentially represents a groundbreaking alternative to more expensive remediation options, further research efforts are needed to clarify factors and conditions affecting the snorkel-driven biodegradation processes and to identify suitable configurations for field applications.