Oil Extraction Activities Research Articles

Multi-Criteria Analysis of Different Approaches to Protect the Marine and Coastal Environment from Oil Spills

Marine pollution has many different sources. This study focuses on oil spills that may occur after a ship collision or during oil extraction and other oil tanker activities. The most critical oil spill accidents are presented, followed by the regulatory framework on maritime oil spill management. Among the measures taken towards the protection of the marine and coastal environment from oil pollution are floating booms and barriers, oil collecting materials and vessels, absorbent materials, chemical dispersants, other chemicals, physical degradation, biodegradation, on-site oil burning. These measures may assist coastal facilities and local authorities in their strategic development of oil spill mitigation planning and response towards coastal and marine protection from oil spills. In the present paper, the aim is to rank the approaches of dealing with the oil spill by means of a multicriteria method. The theoretical background of the selected multicriteria method, called PROMETHEE, is briefly presented; necessary to understand the ranking of the treatment approaches as well as the subsequent findings of the possible criteria for the analysis. Almost all of the scenarios evaluated rank floating booms and barriers as the most suitable methods to deal with oil spill containment, followed by oil collecting materials and vessels.

Bacterial Diversity and the Geochemical Landscape in the Southwestern Gulf of Mexico.

Marine sediments are an example of one of the most complex microbial habitats. These bacterial communities play an important role in several biogeochemical cycles in the marine ecosystem. In particular, the Gulf of Mexico has a ubiquitous concentration of hydrocarbons in its sediments, representing a very interesting niche to explore. Additionally, the Mexican government has opened its oil industry, offering several exploration and production blocks in shallow and deep water in the southwestern Gulf of Mexico (swGoM), from which there are no public results of conducted studies. Given the higher risk of large-scale oil spills, the design of contingency plans and mitigation activities before oil exploitation is of growing concern. Therefore, a bacterial taxonomic baseline profile is crucial to understanding the impact of any eventual oil spill. Here, we show a genus level taxonomic profile to elucidate the bacterial baseline, pointing out richness and relative abundance, as well as relationships with 79 abiotic parameters, in an area encompassing ∼150,000 km2, including a region where the exploitation of new oil wells has already been authorized. Our results describe for the first time the bacterial landscape of the swGoM, establishing a bacterial baseline “core” of 450 genera for marine sediments in this region. We can also differentiate bacterial populations from shallow and deep zones of the swGoM based on their community structure. Shallow sediments have been chronically exposed to aromatic hydrocarbons, unlike deep zones. Our results reveal that the bacterial community structure is particularly enriched with hydrocarbon-degrading bacteria in the shallow zone, where a greater aromatic hydrocarbon concentration was determined. Differences in the bacterial communities in the swGoM were also observed through a comprehensive comparative analysis relative to various marine sediment sequencing projects, including sampled sites from the Deep Water Horizon oil spill. This study in the swGoM provides clues to the bacterial population adaptation to the ubiquitous presence of hydrocarbons and reveals organisms such as Thioprofundum bacteria with potential applications in ecological surveillance. This resource will allow us to differentiate between natural conditions and alterations generated by oil extraction activities, which, in turn, enables us to assess the environmental impact of such activities.

Assessment of the bacterial community structure in shallow and deep sediments of the Perdido Fold Belt region in the Gulf of Mexico.

The Mexican region of the Perdido Fold Belt (PFB), in northwestern Gulf of Mexico (GoM), is a geological province with important oil reservoirs that will be subjected to forthcoming oil exploration and extraction activities. To date, little is known about the native microbial communities of this region, and how these change relative to water depth. In this study we assessed the bacterial community structure of surficial sediments by high-throughput sequencing of the 16S rRNA gene at 11 sites in the PFB, along a water column depth gradient from 20 to 3,700 m, including five shallow (20–600 m) and six deep (2,800–3,700 m) samples. The results indicated that OTUs richness and diversity were higher for shallow sites (OTUs = 2,888.2 ± 567.88; H′ = 9.6 ± 0.85) than for deep sites (OTUs = 1,884.7 ± 464.2; H′ = 7.74 ± 1.02). Nonmetric multidimensional scaling (NMDS) ordination revealed that shallow microbial communities grouped separately from deep samples. Additionally, the shallow sites plotted further from each other on the NMDS whereas samples from the deeper sites (abyssal plains) plotted much more closely to each other. These differences were related to depth, redox potential, sulfur concentration, and grain size (lime and clay), based on the environmental variables fitted with the axis of the NMDS ordination. In addition, differential abundance analysis identified 147 OTUs with significant fold changes among the zones (107 from shallow and 40 from deep sites), which constituted 10 to 40% of the total relative abundances of the microbial communities. The most abundant OTUs with significant fold changes in shallow samples corresponded to Kordiimonadales, Rhodospirillales, Desulfobacterales (Desulfococcus), Syntrophobacterales and Nitrospirales (GOUTA 19, BD2-6, LCP-6), whilst Chromatiales, Oceanospirillales (Amphritea, Alcanivorax), Methylococcales, Flavobacteriales, Alteromonadales (Shewanella, ZD0117) and Rhodobacterales were the better represented taxa in deep samples. Several of the OTUs detected in both deep and shallow sites have been previously related to hydrocarbons consumption. Thus, this metabolism seems to be well represented in the studied sites, and it could abate future hydrocarbon contamination in this ecosystem. The results presented herein, along with biological and physicochemical data, constitute an available reference for further monitoring of the bacterial communities in this economically important region in the GoM.

Visibility impacts at Class I areas near the Bakken oil and gas development

ABSTRACTOil and gas activities have occurred in the Bakken region of North Dakota and nearby states and provinces since the 1950s but began increasing rapidly around 2008 due to new extraction methods. Three receptor-based techniques were used to examine the potential impacts of oil and gas extraction activities on airborne particulate concentrations in Class I areas in and around the Bakken. This work was based on long-term measurements from the Interagency Monitoring of Protected Visual Environments (IMPROVE) monitoring network. Spatial and temporal patterns in measured concentrations were examined before and after 2008 to better characterize the influence of these activities. A multisite back-trajectory analysis and a receptor-based source apportionment model were used to estimate impacts. Findings suggest that recent Bakken oil and gas activities have led to an increase in regional fine (PM2.5—particles with aerodynamic diameters <2.5 µm) soil and elemental carbon (EC) concentrations, as well as coarse mass (CM = PM10–PM2.5). Influences on sulfate and nitrate concentrations were harder to discern due to the concurrent decline in regional emissions of precursors to these species from coal-fired electric generating stations. Impacts were largest at sites in North Dakota and Montana that are closest to the most recent drilling activity.Implications: The increase in oil and gas activities in the Bakken region of North Dakota and surrounding areas has had a discernible impact on airborne particulate concentrations that impact visibility at protected sites in the region. However, the impact has been at least partially offset by a concurrent reduction in emissions from coal-fired electric generating stations. Continuing the recent reductions in flaring would likely be beneficial for the regional visual air quality.

Part B: Morphometric and transcriptomic responses to sub-chronic exposure to the polycyclic aromatic hydrocarbon phenanthrene in the fathead minnow (Pimephales promelas)

Phenanthrene is a tricyclic polycyclic aromatic hydrocarbon and environmental contaminant found in high concentrations around urban catchments and in the vicinity of oil extraction activities. Fish exposed to phenanthrene can exhibit altered reproductive hormone profiles and/or differences within gonadosomatic index and altered gamete proportions, but the mechanisms underlying these changes are not fully understood. In this study, we conducted a sub-chronic bioassay and measured transcriptional responses in the liver, the major tissue involved in generating lipids for oocyte growth. Adult male and female fathead minnow (Pimephales promelas) were exposed to an average measured concentration of 202 μg phenanthrene/L for a 7 week period. Condition factor was reduced in both males and females, while female fish also showed decreased gonadosomatic index relative to control females. In females exposed to phenanthrene, perinucleolar proportions were increased ∼1.9-fold relative to the control group whereas the proportions of vitellogenic oocytes decreased ∼8.8 fold. In males exposed to phenanthrene, spermatogonia proportions were increased ∼2.3 fold in testicular tissues compared to control fish. Thus, gametes were at an earlier stage of maturation in phenanthrene-treated fish compared to controls. However, no differences were detected in the production of 17β-estradiol or testosterone from the gonad in either sex. Catalase activity was also assessed in the liver as a measure of oxidative stress and this biomarker did not change in activity in either sex. In addition to endpoints in the ovary, the female hepatic transcriptome was measured, as this tissue produces lipids for oocyte maturation. Transcriptomic responses to phenanthrene exposure suggested a reduction in vitellogenin mRNA, and lipid metabolism and immune system pathways. Comparisons of hepatic transcriptome responses with Part A (72 h phenanthrene exposure) showed that energy homeostasis pathways were consistently altered following phenanthrene exposure over multiple durations and concentrations. We suggest that altered energy homeostasis may be adversely affecting reproductive efforts, as impaired reproduction has been observed in other studies investigating polycyclic aromatic hydrocarbons.

The Validity of Knock-for-Knock Clauses in Comparative Perspective

Abstract: This article discusses the validity of so-called knock-for-knock clauses, by which parties to offshore oil and gas or maritime contracts agree that each of them will cover its own losses regardless of who caused them. The issue of validity of such clauses and of the liability exclusions they contain is analysed in a comparative perspective between the law of their tradition of origin (common law, especially UK law) and Nordic civil law, where such agreements are also frequently used, namely in the context of oil extraction activities in the North Sea. Based on an assessment of the different criteria used to promote or dismiss knock-for-knock clauses in case law and academic literature, the article reaches the conclusion that the question of whether knock-for-knock clauses should be held valid depends on whose interests are being considered, and that further research is warranted on the efficiency of mechanisms supposed to replace the deterrence effect of tort or contractual liability. Résumé: Le présent article traite de la validité des clauses dites knock-for-knock, par lesquelles les parties à des contrats en matière de production d´énergie offshore et de droit maritime conviennent que chacune des parties supportera les dommages qu´elle subit sans tenir compte de qui les a causés. La question de la validité de telles clauses et des exclusions de responsabilité qu´elles contiennent est analysée dans une perspective de droit comparé entre le droit de leur tradition d´origine (le droit commun, plus particulièrement le droit anglais) et le droit civil nordique, dans lequel de telles clauses sont également fréquemment employées, en particulier en relation avec les activités d ´extraction pétrolière dans la Mer du Nord. Sur la base d´une discussion des différents arguments avancés en faveur ou contre les clauses knock-for-knock, l´article parvient à la conclusion que la question de leur validité peut recevoir différentes réponses en fonction des acteurs dont les intérêts sont considérés. De surcroît, des recherches approfondies concernant l’efficacité de mesures contractuelles de droit public de sécurité et de prévention des accidents sont nécessaires afin de déterminer si l’effet de dissuasion visé par la responsabilité délictuelle ou contractuelle peut être atteint par d´autres moyens. Zusammenfassung: Dieser Artikel diskutiert die Gültigkeit von sogenannten Knockfor-Knock-Klauseln, durch die Parteien zu Offshore-Öl- und Gas- oder Seeverkehrsverträgen zustimmen, dass jeder von ihnen seine eigenen Verluste abdecken wird, unabhängig davon, wer sie verursacht hat. Die Frage der Gültigkeit solcher Klauseln und die darin enthaltenen Haftungsausschlüsse wird in einer vergleichenden Perspektive zwischen dem Gesetz ihrer Herkunft (Common Law, insbesondere dem britischen Recht) und dem nordischen Zivilrecht analysiert, wobei auch solche Vereinbarungen häufig verwendet werden im Rahmen der Ölförderung in der Nordsee. Auf der Grundlage einer Einschätzung der verschiedenen Kriterien, die zur Förderung oder Entlassung von Knock-for-Knock-Klauseln in der Rechtsprechung und der akademischen Literatur verwendet werden, kommt der Artikel zu dem Schluss, dass die Frage, ob Knock-for-Knock Klauseln gültig gehalten werden sollte, davon abhängt, wessen Interessen werden berücksichtigt, und dass weitere Untersuchungen über die Effizienz von Mechanismen, die die Abschreckungseffekte der unerlaubten Handlung oder der vertraglichen Haftung ersetzen sollen, gerechtfertigt sind.

The influence of local oil exploration and regional wildfires on summer 2015 aerosol over the North Slope of Alaska

Abstract. The Arctic is warming at an alarming rate, yet the processes that contribute to the enhanced warming are not well understood. Arctic aerosols have been targeted in studies for decades due to their consequential impacts on the energy budget, both directly and indirectly through their ability to modulate cloud microphysics. Even with the breadth of knowledge afforded from these previous studies, aerosols and their effects remain poorly quantified, especially in the rapidly changing Arctic. Additionally, many previous studies involved use of ground-based measurements, and due to the frequent stratified nature of the Arctic atmosphere, brings into question the representativeness of these datasets aloft. Here, we report on airborne observations from the US Department of Energy Atmospheric Radiation Measurement (ARM) program's Fifth Airborne Carbon Measurements (ACME-V) field campaign along the North Slope of Alaska during the summer of 2015. Contrary to previous evidence that the Alaskan Arctic summertime air is relatively pristine, we show how local oil extraction activities, 2015's central Alaskan wildfires, and, to a lesser extent, long-range transport introduce aerosols and trace gases higher in concentration than previously reported in Arctic haze measurements to the North Slope. Although these sources were either episodic or localized, they serve as abundant aerosol sources that have the potential to impact a larger spatial scale after emission.

Petro-Geographies and Hydrocarbon Realities in Latin America

Petro-Geographies and Hydrocarbon Realities in Latin America Matthew Fry, Guest Editor and Elvin Delgado, Guest Editor Despite the lofty goals of the Paris Climate Agreement and the growing availability of renewable sources of energy, the current spatial extent and social implications of oil and natural gas production and consumption are at their largest ever. With more than two million active wells and over 2.5 million km of pipelines around the globe (CIA, 2017; World Oil, 2017), the expanding hydrocarbon extraction footprint (Allred et al., 2015) includes the development of new fields, new governance structures, and new territorialization processes throughout Latin America. This is the first JLAG issue fully dedicated to the geographies of oil and natural gas in Latin America. As the research articles, book reviews, and conclusion demonstrate, the “habits of oil rule” (Lu et al., 2017) and the global reach of hydrocarbons actively (re)create petro-geographies and hydrocarbon realities throughout Latin America. Latin America’s ties to the global economy, though long established through silver, sugar, coffee, cocaine and other resources (Joseph & Rosenberg, 2006), also entail a history of oil and natural gas production, distribution, transformation, and consumption. The eight research articles in this Special Issue provide empirical and theoretical engagements with hydrocarbon development, addressing themes that include boomtown scenarios, state interventions, conflict over sovereignty, new hydrocarbon territorialities, the socioeconomic implications of shale and unconventional hydrocarbons, the role of reserve replacement strategies, unfolding Caribbean energy developments, and new dispossession laws. The petro-geographies (re)produced and hydrocarbon realities uncovered reveal the complexities of energy landscapes across a variety of scales and regions in Latin America. Research articles in this special issue follow three overlapping themes: (1) oil politics and hydrocarbon rules; (2) boomtown scenarios and community dynamics; and (3) territorialization, conflict, and integration of regional hydrocarbon systems. In the last two decades, Latin American political ideologies shifted from conservative neoliberal economics to a center-left, post-neoliberal, and neo-extractivist model (Gudynas, 2009; Bebbington & Humphreys Bebbington, 2010). Hydrocarbon research that attended to this shift focused on government control over fossil fuels (Perreault &Valdivia, 2010), the use of oil and gas revenues [End Page 10] (Coronil, 1997; Delgado, 2017), and the strategies adopted to deal with the socio-environmental consequences of extraction activities (O’Rourke & Connolly, 2003). We know, for example, that economic dependence on resource extraction affects the institutions, their governance, and the legal frameworks created to regulate extraction and environmental outcomes. Because of constitutional innovations that aimed to protect its natural heritage, Ecuador provides a unique laboratory to investigate how neo-extractivist strategies to secure oil rents overlap with strict environmental laws. In the first research article in this issue, Teresa Bornschlegl’s “Petro-geographies and the Dialectic of the Everyday” uses critical state theory and institutional ethnography to examine the daily practices of the Ecuadorian Ministry of the Environment’s enforcement of hydrocarbon laws as it struggles with post-extractivist and extractivist forces emanating from the Ecuadorian state. Bornschlegl argues that the habits of oil rule, what Lu et al. (2017, p. 69) call “the entrenched tendencies of governing through practices of the oil industry,” place obstacles to the enforcement of environmental laws while at the same time creating the conditions for its continuation. Through “a process that produces its own becoming,” the article details how other components of the state government and entrenched tendencies of the oil industry create obstacles that perpetuate a positive feedback of environmental inspections, which works to distract environmental enforcement officers from focusing on the prevention of actual environmental damage caused by oil extraction activities. Controlling access to hydrocarbons also shapes Latin America’s trade and international relations. In Mexico, for example, the 2013 energy reforms opened the hydrocarbon sector to private and foreign firm investments. In “Canadian Capital and the Denationalization of the Mexican Energy Sector,” Aleida Hernandez Cervantes and Anna Zalik show how access to hydrocarbon capital shaped Mexico’s “juridical structures of dispossession” by privatizing a public resource in order to facilitate the accumulation of capital by international entities. In this case, the 2014 crash in global oil prices not only affected Canada’s tar sands oil production, but encouraged Canadian firms, government officials...

Measurement of area and personal breathing zone concentrations of diesel particulate matter (DPM) during oil and gas extraction operations, including hydraulic fracturing

ABSTRACTDiesel engines serve many purposes in modern oil and gas extraction activities. Diesel particulate matter (DPM) emitted from diesel engines is a complex aerosol that may cause adverse health effects depending on exposure dose and duration. This study reports on personal breathing zone (PBZ) and area measurements for DPM (expressed as elemental carbon) during oil and gas extraction operations including drilling, completions (which includes hydraulic fracturing), and servicing work.Researchers at the National Institute for Occupational Safety and Health (NIOSH) collected 104 full-shift air samples (49 PBZ and 55 area) in Colorado, North Dakota, Texas, and New Mexico during a four-year period from 2008–2012. The arithmetic mean (AM) of the full shift TWA PBZ samples was 10 µg/m3; measurements ranged from 0.1–52 µg/m3. The geometric mean (GM) for the PBZ samples was 7 µg/m3. The AM of the TWA area measurements was 17 µg/m3 and ranged from 0.1–68 µg/m3. The GM for the area measurements was 9.5 µg/m3. Differences between the GMs of the PBZ samples and area samples were not statistically different (P > 0.05).Neither the Occupational Safety and Health Administration (OSHA), NIOSH, nor the American Conference of Governmental Industrial Hygienists (ACGIH) have established occupational exposure limits (OEL) for DPM. However, the State of California, Department of Health Services lists a time-weighted average (TWA) OEL for DPM as elemental carbon (EC) exposure of 20 µg/m3. Five of 49 (10.2%) PBZ TWA measurements exceeded the 20 µg/m3 EC criterion. These measurements were collected on Sandmover and Transfer Belt (T-belt) Operators, Blender and Chemical Truck Operators, and Water Transfer Operators during hydraulic fracturing operations.Recommendations to minimize DPM exposures include elimination (locating diesel-driven pumps away from well sites), substitution, (use of alternative fuels), engineering controls using advanced emission control technologies, administrative controls (configuration of well sites), hazard communication, and worker training.

Distribution, contents and health risk assessment of metal(loid)s in small-scale farms in the Ecuadorian Amazon: An insight into impacts of oil activities

In the last 50years, oil extraction activities in the Northeast Amazonian Region (NAR) of Ecuador impacted ecosystems and may still affect the local population health. To our knowledge, no previous studies have determined the concentrations of metal(loid)s in the oil Ecuadorian Amazon environment. A total of 15 small farms, located in the Orellana and Sucumbíos provinces, were sampled in order to determine the concentrations of As, Ba, Co, Cu, Cd, Cr, Mn, Mo, Ni, Pb, V and Zn in soils, crops, drinking water and air (PM10). Among non-essential metal(loid)s, Ba concentrations in soils exceeded the Ecuadorian limits of 200mgkg−1 in 53% of the sampling sites. In crops, Cd concentrations in cacao and Pb in manioc exceeded the FAO/WHO recommendations. In drinking water and PM10, regulated metal(loid)s did not exceed the international thresholds. Nevertheless metals such as Ba and Mo showed the highest annual mean concentrations in PM10 in both sampling sites. Natural (bedrock, volcanic ashes) and anthropogenic (oil activities, agrochemical products) sources could explain the high content of some meta(loid)s in the environment. According to the hazard quotient and cancer risk indexes, crops and water ingestion represent 71% and 88% of the exposure pathways for non-carcinogenic elements in adults and children respectively while inhalation is the main exposure pathways for carcinogenic elements for the whole population. Both indexes were 2 to 13 times higher than the US EPA recommended values. However, estimates of exposure pathways should be considered taking into account the risk perception of residents: they may be overestimated for people who are able to change their dietary and/or agricultural practices to limit their exposure, or underestimated in the case of persons who are socio-economically vulnerable and who cannot leave the impacted areas.

Exploring the links between groundwater quality and bacterial communities near oil and gas extraction activities

Bacterial communities in groundwater are very important as they maintain a balanced biogeochemical environment. When subjected to stressful environments, for example, due to anthropogenic contamination, bacterial communities and their dynamics change. Studying the responses of the groundwater microbiome in the face of environmental changes can add to our growing knowledge of microbial ecology, which can be utilized for the development of novel bioremediation strategies. High-throughput and simpler techniques that allow the real-time study of different microbiomes and their dynamics are necessary, especially when examining larger data sets. Matrix-assisted laser desorption-ionization (MALDI) time-of-flight mass spectrometry (TOF-MS) is a workhorse for the high-throughput identification of bacteria. In this work, groundwater samples were collected from a rural area in southern Texas, where agricultural activities and unconventional oil and gas development are the most prevalent anthropogenic activities. Bacterial communities were assessed using MALDI-TOF MS, with bacterial diversity and abundance being analyzed with the contexts of numerous organic and inorganic groundwater constituents. Mainly denitrifying and heterotrophic bacteria from the Phylum Proteobacteria were isolated. These microorganisms are able to either transform nitrate into gaseous forms of nitrogen or degrade organic compounds such as hydrocarbons. Overall, the bacterial communities varied significantly with respect to the compositional differences that were observed from the collected groundwater samples. Collectively, these data provide a baseline measurement of bacterial diversity in groundwater located near anthropogenic surface and subsurface activities.

Characterization of bacterial diversity in contaminated groundwater using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry

Groundwater is a major source for drinking water in the United States, and therefore, its quality and quantity is of extreme importance. One major concern that has emerged is the possible contamination of groundwater due to the unconventional oil and gas extraction activities. As such, the impacts of exogenous contaminants on microbial ecology is an area to be explored to understand what are the chemical and physical conditions that allow the proliferation of pathogenic bacteria and to find alternatives for water treatment by identifying organic-degrading bacteria. In this work, we assess the interplay between groundwater quality and the microbiome in contaminated groundwaters rich in hydrocarbon gases, volatile organic and inorganic compounds, and various metals. Opportunistic pathogenic bacteria, such as Aeromonas hydrophila, Bacillus cereus, Pseudomonas aeruginosa, and Stenotrophomonas maltophilia, were identified, increasing the risk for consumption of and exposure to these contaminated groundwaters. Additionally, antimicrobial tests revealed that many of the identified bacteria were resistant to different antibiotics. The MALDI-TOF MS results were successfully confirmed with 16S rRNA gene sequencing, proving the accuracy of this high-throughput method. Collectively, these data provide a seminal understanding of the microbial populations in contaminated groundwater overlying anthropogenic activities like unconventional oil and gas development.

MALDI-TOF MS for the Identification of Cultivable Organic-Degrading Bacteria in Contaminated Groundwater near Unconventional Natural Gas Extraction Sites.

Groundwater quality and quantity is of extreme importance as it is a source of drinking water in the United States. One major concern has emerged due to the possible contamination of groundwater from unconventional oil and natural gas extraction activities. Recent studies have been performed to understand if these activities are causing groundwater contamination, particularly with respect to exogenous hydrocarbons and volatile organic compounds. The impact of contaminants on microbial ecology is an area to be explored as alternatives for water treatment are necessary. In this work, we identified cultivable organic-degrading bacteria in groundwater in close proximity to unconventional natural gas extraction. Pseudomonas stutzeri and Acinetobacter haemolyticus were identified using matrix-assisted laser desorption/ionization-time-of-flight-mass spectrometry (MALDI-TOF MS), which proved to be a simple, fast, and reliable method. Additionally, the potential use of the identified bacteria in water and/or wastewater bioremediation was studied by determining the ability of these microorganisms to degrade toluene and chloroform. In fact, these bacteria can be potentially applied for in situ bioremediation of contaminated water and wastewater treatment, as they were able to degrade both compounds.

Modelling the transport of oil after a proposed oil spill accident in Barents Sea and its environmental impact on Alke species

Accidental oil spills can have significant effect on the coastal and marine environment. As the oil extraction and exploration activities increase in the Barents Sea, it is of increasingly importance to investigate the potential oil spill incidents associated with these activities. In this study, the transport and fate of oil after a proposed oil spill incident in Barents Sea was modelled by oil spill contingency and response model OSCAR. The possibility that the spilled oil reach the open sea and the strand area was calculated respectively. The influence area of the incident was calculated by combining the results from 200 simulations. The possibility that the spilled oil reach Alke species, a vulnerable species and on the National Red List of birds in Barents Sea, was analyzed by combining oil spill modelling results and the Alke species distribution data. The results showed that oil is dominated with a probability of 70-100% in the open sea to reach an area in a radius of 20km from the release location after 14 days of release. The probability reduces with the increasing distances from the release location. It is higher possibility that the spilled oil will reach the Alke species in the strand area than in the open sea in the summer. The total influence area of the release is 11 429 km2 for the surface water and 1528 km2 for the coastal area.

Essential oil extraction, chemical analysis and anti-Candida activity of Foeniculum vulgare Miller – new approaches

A comprehensive study on essential oil samples of Foeniculum vulgare Miller from Tarquinia (Italy) is reported. A 24-h systematic steam distillation was performed on different harvested samples applying different extraction times. The GC-MS analysis of the residue outcome showed o-cymene, α-phellandrene, α-pinene and estragole as the major constituents. The predominance and continued presence of o-cymene makes this fennel oil a rather unique chemotype. An evident correlation between the antifungal activity and phenological stage is demonstrated. The most active fractions were particularly rich in estragole, as well as a significant amount of fenchone that possibly exerts some additive effect in the expression of overall antifungal potency. Pre-fruiting material produced oil particularly rich in o-cymene. With reference to the duration of the extraction, the maximum amount of oil was released within the first 3 h, whereas the reproductive phase material needed at least 6 h for the extraction.

Water contamination from oil extraction activities in Northern Peruvian Amazonian rivers

Oil extraction activities in the Northern Peruvian Amazon have generated a long-standing socio-environmental conflict between oil companies, governmental authorities and indigenous communities, partly derived from the discharge of produced waters containing high amounts of heavy metals and hydrocarbons. To assess the impact of produced waters discharges we conducted a meta-analysis of 2951 river water and 652 produced water chemical analyses from governmental institutions and oil companies reports, collected in four Amazonian river basins (Marañon, Tigre, Corrientes and Pastaza) and their tributaries. Produced water discharges had much higher concentrations of chloride, barium, cadmium and lead than are typically found in fresh waters, resulting in the widespread contamination of the natural water courses. A significant number of water samples had levels of cadmium, barium, hexavalent chromium and lead that did not meet Peruvian and international water standards. Our study shows that spillage of produced water in Peruvian Amazon rivers placed at risk indigenous population and wildlife during several decades. Furthermore, the impact of such activities in the headwaters of the Amazon extended well beyond the boundaries of oil concessions and national borders, which should be taken into consideration when evaluating large scale anthropogenic impacts in the Amazon.

BIOREMEDIATION OF SOILS FROM OIL SPILL IMPACTED SITES USING BIOAUGMENTATION WITH BIOSURFACTANTS PRODUCING, NATIVE, FREE-LIVING NITROGEN FIXING BACTERIA

Oil spills are the most common source of environmental damage in areas with oil extraction activities. Bioaugmentation is a bioremediation technology that involves increasing microbiotas that can remove contaminant compounds from soils or water. This can be achieved by supplying exogenous microorganisms or by increasing the abundance of native microorganisms able to remove the contaminants. As biosurfactants enhance the solubility and bioavailability of hydrophobic compounds, the addition of native bacteria that produce biosurfactants may improve the rates of hydrocarbons biodegradation at oil spill impacted sites. The objective of this study was to investigate the effectiveness of using the bioaugmentation of native, free-living nitrogen fixing bacteria (NFB) that are able to remove hydrocarbons and produce biosurfactant compounds, to bioremediate soils at long term oil spill impacted sites containing total hydrocarbon (TH) levels of 120 000 ppm. For this study, two NFB that produce biosurfactants were selected from a group of 24 previously isolated from a long-term oil spill impacted site. After 16 months of bioaugmentation, the hydrocarbons removal reached 80 %. The NFB count increased from 13×10 4 colony-forming units (CFU) to 2×10 9 CFU, and the total bacterial population increased from 5×10 4 CFU to 22×10 11 CFU. According to literature, this is the first bioaugmentation study using native NFB biosurfactant producers to bioremediate soils from aged oil spill impacted sites. As such, these results demonstrate the potential of this bioaugmentation strategy for the bioremediation of oil spill impacted sites, especially those low in nitrogen.

Phenology of the multi-use tree species Carapa guianensis in a floodplain forest of the Amazon Estuary

Carapa guianensis is a multi-use tree species that is used for the production of timber and non-timber forest products (NTFPs) that are used and sold by rural Amazonian populations. Here we aimed to evaluate the phenophases of C. guianensis in varzea forest and relate them to climatic seasonality. Phenophases of flowering (flower buds and open flowers), fruiting (unripe and ripe fruits), and leaf flush and leaf fall were recorded for 30 individual trees during a 25 month period. Relationships between rainfall and the proportion of trees in each phenophase were tested using Generalised Linear Models with quasi-binomial errors. Flowering was found to peak in the driest months of the year (September to December), while fruiting peaked during the wettest months of the year when river levels are at their highest (January to May). Leaf flush and leaf fall occurred simultaneously throughout the year, regardless of seasonality. Strong seasonality in flowering and fruiting of C. guianensis likely represents a reproductive strategy that maximizes pollination and hydrochorous seed dispersal. This study has the potential to aid in planning the timing of seed collection and oil extraction activities, thus contributing to the sustainable exploitation of this tree.

Ferruginous hawk demography in areas differing in energy extraction activity

ABSTRACTThe recent expansion of oil and gas extraction activity on the Great Plains, USA, has occurred with little understanding of potential effects of the activity on wildlife populations. We monitored the demography of breeding ferruginous hawks (Buteo regalis) in 2 areas of western North Dakota, USA, subject to different intensities of energy extraction. Northwestern North Dakota is the heart of the Bakken Shale, where oil and gas extraction activity has been intense (e.g., 1,273 new oil wells from 2011–2013 in our high‐intensity study area) in recent years. In contrast, such activity has occurred at a relatively low intensity (e.g., 18 new oil wells from 2011–2013 in our low‐intensity study area) in southwestern North Dakota. Ferruginous hawks in the 2 areas had similar densities of nesting pairs, with comparable fledging success. However, between‐year re‐use of nest sites was significantly lower in the area with high‐intensity energy extraction (1 of 8) than the area of low‐intensity (8 of 10); also, re‐use of nests in the high‐intensity area was considerably lower than reported from other parts of the range of the species. Thus, although high‐intensity energy extraction activity had no apparent impact on immediate reproductive success of ferruginous hawks, long‐term population declines could be expected in our northern study area given the unusually low rate of nest‐site re‐use. © 2016 The Wildlife Society.

Investigation of essential oil extraction and antioxidant activity of Echinophora platyloba DC. using supercritical carbon dioxide

Essential oils of Echinophora platyloba DC. were extracted with application of supercritical carbon dioxide (SC-CO2) and hydro-distillation (HD) extraction methods. The effects of SC-CO2 experimental variables such as pressure (80–240bar), temperature (308–328K), particle size (0.30–0.90mm), and dynamic extraction time (30–150min) on the extraction yield and antioxidant activity of the prepared essential oils were investigated using a central composite design (CCD). The experimental data were fitted well to a second-order polynomial equation using regression analysis. The maximum yield obtained at the optimal conditions (1.1850±0.0550%) was more than that achieved by hydro-distillation method (1.120±0.0440%). The chemical compositions of the SC-CO2 and HD extracts were identified by GC–MS analysis and determined by GC–FID analytical method. The main components of the essential oil extracted by SC-CO2 method were found to be Linalool (16.02%), Trans-β-Ocimene (11.58%), α-Pinene (7.10%), Anisole, 2,4,6-trimethyl (6.98%) and Spathulenol (5.29%). Moreover, the components of the essential oil extracted by HD method were Trans-β-Ocimene (46.99%), Spathulenol (9.04%), β-Myrcene (6.24%), dl-Limonene (5.38%) and α-Pinene (4.55%). The antioxidant and free radical scavenging activities of the obtained essential oils were determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH). Radical scavenging activity of the essential oils extracted by SC-CO2 and hydro-distillation methods exhibited an IC50 of 122.62μg/ml and 413.35μg/ml, respectively. To the best of researchers’ knowledge, the present study provides the first report addressing the essential oil extraction of Echinophora platyloba DC. using supercritical carbon dioxide technique.