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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Fate and Impacts of Vegetable Oil Spills in Aquatic Environments

Salam, Darine January 2011 (has links)
No description available.
52

In what way are oil and gas companies accountable for the environmental impact caused by oil spills?

Lisnic, Polina January 2022 (has links)
The interdependence and cooperation in the international arena have brought different benefits and made the world more interconnected. As the global system became more complex new types of state and non-state actors have emerged. Institutions have also been introduced with the specific objective to support in upholding mutual agreements and to make sure that the compliance between the several actors is followed. These institutions aim not only to uphold the stability of the system but also to provide support for power asymmetries in a competitive international system. Yet, the difficulty of holding powerful actors accountable is present in the global governance debates.  On one hand, Robert Keohane (2003) argues that democratic accountability is not possible due to the lack of a global public but suggests accountability mechanisms to understand who should hold actors to their accountability. On the other hand, Michael Goodhart (2011) offers an alternative view by arguing that the focus should be on norms, rather than agents, and these norms should carry a democratic standard.  This paper aims to investigate Repsol and more specifically, focus on the oil spill at the La Pampilla Refinery in Peru. The objective is to understand the accountability (or lack thereof) of the oil and gas companies for the harmful, environmental impact that was caused by the oil spill. The dynamics between the actors involved in this case will be studied and analyzed with the aim to expose any shortcomings of accountability in global governance. As a result, this case suggests that without firmer rules from the host country, the business industries are unlikely to make big amendments to their operations to prevent future oil spills. The result of this research adds to the IR discussion concerning the need to strengthen international norms and enable the agency of institutions.
53

Photo-induced Toxicity of Deepwater Horizon Spill Oil to Four Native Gulf of Mexico Species

Alloy, Matthew Michael 12 1900 (has links)
The 2010 Deepwater Horizon oil spill resulted in the accidental release of millions of barrels of crude oil into the Gulf of Mexico (GoM). Photo-induced toxicity following co-exposure to ultraviolet (UV) radiation is one mechanism by which polycyclic aromatic hydrocarbons (PAHs) from oil spills may exert toxicity. Blue crab (Callinectes sapidus) are an important commercial and ecological resource in the Gulf of Mexico and their largely transparent larvae may make them sensitive to PAH photo-induced toxicity. Mahi-mahi (Coryphaena hippurus), an important fishery resource, have positively buoyant, transparent eggs. These characteristics may result in mahi-mahi embryos being at particular risk from photo-induced toxicity. Red drum (Sciaenops ocellatus) and speckled seatrout (Cynoscion nebulosus) are both important fishery resources in the GoM. They spawn near-shore and produce positively buoyant embryos that hatch into larvae in about 24 h. The goal of this body of work was to determine whether exposure to UV as natural sunlight enhances the toxicity of crude oil to early lifestage GoM species. Larval and embryonic organisms were exposed to several dilutions of water accommodated fractions (WAF) from several different oils collected in the field under chain of custody during the 2010 spill and two to three gradations of natural sunlight in a factorial design. Here, we report that co-exposure to natural sunlight and oil significantly reduced larval survival and embryo hatch compared to exposure to oil alone.
54

Simulating Thermal and Chemical Spills in Coupled Cooling Reservoirs

Qiu, Bin 08 1900 (has links)
Hot water discharges and potential chemical spills are factors that threaten water quality in cooling reservoirs of chemical and power plants. In this thesis, three models are used to analyze the impact of these factors in a particular case study.
55

Behavioral constraints on harlequin duck population recovery from the Exxon Valdez oil spill in Prince William Sound, Alaska

Rizzolo, Daniel J. 05 February 2004 (has links)
I investigated the relationship between harlequin duck (Histrionicus histrionicus) behavior and lack of recovery from the Exxon Valdez oil spill in Prince William Sound, Alaska. First, I evaluated the hypothesis that harlequin ducks in winter have little flexibility to increase foraging time in response to disturbance because they are constrained to forage during daylight. Eight radio-tagged harlequin ducks wintering in Resurrection Bay, Alaska were monitored for evidence of dive-feeding at night. Each radio-tagged individual was detected during an average of 19.5 of 22 nocturnal monitoring sessions and signal loss indicative of diving behavior was not detected during a total of 780 minutes of signal monitoring. In contrast, the same 8 radio-tagged birds were detected during an average of 9.1 of 12 daytime signal monitoring sessions and signal loss indicated diving behavior during an average of 62 �� 7% of 5-minute daytime monitoring periods (total of 364 minutes of signal monitoring). Thus the harlequin ducks monitored in this study rarely, if ever, fed by diving at night, possibly due to reduced foraging efficiency and (or) increased predation risk at night. This result suggests that harlequin ducks in mid-winter may be severely time-limited in their foraging, especially in northern parts of their winter range. Therefore, subtle changes in energy requirements and (or) time-activity budgets as a result of continued exposure to residual oil from the Exxon Valdez oil spill may affect the ability of harlequin ducks to meet their daily energy requirements. Second, I tested the hypothesis that exposure to crude oil affects time-activity budgets of harlequin ducks. Controlled oil-dosing and plumage-oiling experiments were conducted using adult female harlequin ducks in captivity. I found no evidence that ingestion of weathered Prudhoe Bay crude oil affected the occurrence of feeding activity during 30-minute observation periods, nor was there evidence of effects on time spent feeding. Effects of crude oil ingestion on maintenance activity were detected, but were neither consistent between the 2 years of the study, nor dose-dependent for the 2 doses administered (2 and 20 mL kg����� wk�����), and therefore did not strongly support an oil-dosing effect on maintenance activity. Consequently, these results provided little support for the hypothesis that oil ingestion affects time-activity budgets of captive harlequin ducks, at least for the doses and conditions of captivity used in this study. Plumage-oiling reduced feeding activity in captive harlequin ducks. The estimated probability of feeding during 30-minute observation periods for birds in the high-exposure oiling group (5 mL of crude oil) was 53% less than that of non-oiled controls. Oiled birds exhibited a trend of reduced time feeding with increasing level of external-oiling; this effect was greatest among birds in the high-exposure oiling group, which spent 43% less time feeding than non-oiled birds. Reduced feeding was associated with less time in the water dive-feeding and presumably lower heat loss. Trends in the occurrence of maintenance activity and time spent in maintenance activity for birds in the high-exposure treatment suggested plumage-oiling increased maintenance activity, but results were not conclusive. The behavioral changes associated with plumage-oiling in captivity would likely reduce fitness in the wild, where a high proportion of time must be spent in the water feeding. If residual Exxon Valdez oil sequestered in beach sediments enters the water column where it may be encountered by harlequin ducks, external exposure may lead to reduced feeding activity. This, in turn, may compromise survival, particularly during mid-winter when the time available for diurnal foraging is low and maintenance energy requirements are high. / Graduation date: 2004
56

Marine oil pollution control-projections for Hong Kong

Tsui, Kai-man., 徐啓文. January 1996 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
57

Mapeamento de sensibilidade ambiental ao óleo do arquipélago de Ilha Bela - SP /

Lima, Miguel Vieira de. January 2007 (has links)
Resumo: Diretamente sob influência do Canal de São Sebastião - onde está estabelecido o maior terminal petrolífero do Brasil e ocorre intensa movimentação de petroleiros -, a faixa litorânea do município de Ilhabela-SP é freqüentemente impactada por vazamentos de óleo. Daí, sua condição de ser, entre todos os municípios do litoral-norte paulista, aquele que mais é impactado por vazamentos. Trata-se de área com alta relevância ecológica por conter ricos e diversificados recursos biológicos, bem como por apresentar significativa atividade sócio-econômica que envolve o turismo e a pesca. Este estudo apresenta, em escala de detalhe (1:10.000 a 1:25.000), um conjunto de vinte e quatro cartas SAO de caráter operacional e uma de caráter tática para a face oeste da Ilha de São Sebastião. Contempla, ainda, mapas temáticos, quadros de recursos visuais e listagem das espécies encontradas no arquipélago. A elaboração de tais cartas seguiu as recomendações do MMA-Brasil. Ao indicar as áreas historicamente mais atingidas por vazamento de óleo e definir áreas que requerem proteção especial e faixas de sacrifício, este estudo passa, no seu conjunto, a constituir valioso documento a ser usado em planos de contingência e emergência referentes ao arquipélago. / Abstract: Directly influenced by the São Sebastião Channel - where the biggest petroliferous terminal is installed and where occurs the highest numbers of tankers coming alongside - the coast side of Ilha Bela city - SP is frequently damaged by oil spills. Therefore it is considered the most 'harmed by leaking' city in the coast. It is a high ecologically relevant area for its risks and diversified biological resources, as well as for its significant socio-economical activities that involves tourism and fishing. This article shows, in detail (1:10.000 to 1:25.000) a set of twenty-three ESI maps and also a tactical one, facing the west side of São Sebastião Island. It also shows thematic maps, visual resources and a species list from the archipelago. The process to create those maps was strict to the Brazilian Environmental Ministry recommendations. As it indicates the historical areas that were damaged the most for oil spills and as it defines the areas that require special attention and sacrifice areas, it has become, as a whole, a valuable document to be used in emergency and contingency plans for the archipelago. / Orientador: Dimas Dias-Brito / Coorientador: João Carlos Carvalho Milanelli / Banca: Décio Luis Semensatto Junior / Banca: Paulina Setti Riedel / v. 2 - mapas temáticos, quadros descritivos de recursos visuais, listagens de espécies da fauna / Mestre
58

Oregon's Oil: A Geographic View of Petroleum Distribution and Associated Risks

Slyman, Paul M. 21 February 1996 (has links)
Since no local crude oil sources exist, every drop of petroleum consumed in Oregon originates from outside sources and is distributed multi-modally to consumers. As population continues to increase and oil sources dwindle, this reliance may add financial and environmental risks to Oregonian' s quality of life. This paper examines Oregon's oil distribution system, and analyzes the risks oil movements pose in the state. A comprehensive understanding of oil distribution in Oregon can best be gained geographically. Pipelines, ships, barges, railroads and trucks play different roles in this system, yet data for these transport modes are maintained by different groups and unstandardized. Therefore, the data must be normalized to present a map of how oil is being moved around the state. This study sets all levels to a barrels (42 U.S. gallons) per month (assumed 30 days) standard. Oil's role in the economy of our state, most noticeably in the sale of motor gasoline, creates different types of risk. The most obvious risk results from transportation, and Oregon is plagued daily by unintended releases. A second type of risk, supply risk, exists because of our reliance on the petroleum networks of Alaska, Washington and California, and was evident during the 1974 oil embargo. Lastly, economic risk should theoretically be present since Oregon is a downstream consumer from adjacent states. During times of shortages, Oregon should be at the mercy of those who provide its supply. The data do not support this, but suggest that oil is purely a global commodity, and price and supply are determined worldwide in response to typical marketing forces. The distribution systems detailed herein are dynamic, and outside forces such as the proposed export of Alaskan crude oil, the increased exploration of offshore oil fields, and the development of a cross-Cascades pipeline may alter this scheme. Oregonians can ensure the most effective petroleum distribution systems only by understanding them and their associated risks.
59

Oil Spills in New Zealand's Territorial Waters: Fence at the Top of the Cliff?

Hoeberechts, Veronica Anne January 2006 (has links)
Over the last four decades, there have been many catastrophic oil spills in the marine environment and these larger oil spills have often caused environmental devastation especially if they occurred in the coastal marine area. Serious ecological damage can also be caused from operational discharges, ballast and bilge water, from ships within territorial waters. Until now New Zealand has only had relatively minor oil spillages in its coastal waters, primarily from ships' discharge or accidental leaks in port. The possibility however of a major oil spill occurring within our coastal area is considerably higher today than 20 years ago as there has been a significant increase of all types of oil tankers/bulk carriers/container ships to New Zealand. New Zealand is an island nation that relies heavily on the marine environment for commercial operations such as fisheries and tourism and many New Zealanders enjoy recreational, aesthetic and spiritual ties to the coastal marine area. The sustainability of our territorial sea is therefore of paramount importance. A major oil spill could cause widespread ecological damage, cripple or destroy marine/tourism operations and ensure that the human values associated with the coast are lost, possibly for many years. The research reported here addresses the issue of oil spill preparedness and response in New Zealand's waters. A combination of a review of New Zealand's international commitments and domestic legislation and two case studies of high profile oil spills: the Poor Knights Islands Marine Reserve and the Jody F Millennium are used. The research identifies whether the present environmental legislation, that promotes sustainable management, is proactive in the prevention of a major oil spill and concludes that the New Zealand approach reflects a relatively strong Sustainable Imperative position rather than one of Sustainable Development. In implementation it relies heavily on co-management integrated at the regional council level.
60

Numerical simulation of oil spills in coastal areas using shallow water equations in generalised coordinates

Novelli, Guillaume 24 November 2011 (has links)
The pollution generated by accidental marine oil spills can cause persistent ecological disasters and lead to serious social and economical damages. Numerical simulations are a valuable tool to make proper decisions in emergency situation or to plan response actions beforehand. The main objective of this work was to improve SIMOIL, a computational model developed earlier at URV and capable of predicting the evaporation and spreading of massive oil spills in coastal areas. Specifically, a new coastal current model, based on the resolution of the shallow water equations in generalised coordinates, has been developed and validated and then coupled to SIMOIL. The model was specially designed to describe coastal oceanic flows over topography accounting for Coriolis force, eddy viscosity, seabed friction and to couple with SIMOIL in domain with complex boundaries. The equations have been discretized over generalised domains by means of finite differences of second order accuracy. The code was then implemented in FORTRAN. The code has been validated extensively against numerical and experimental flow studies of the bibliography. Finally, the new complete version of SIMOIL, coupling the shallow water model and the oil slick model, has been applied to the study of two accidental oil spills: • A massive leakage from the Repsol's floating dock in the port of Tarragona • The biggest oil spill ever occurred in the Eastern Mediterranean Sea: the 2006 Lebanon oil spill. In both cases, the new version of SIMOIL, demonstrate more accurate predictions of the behaviour of the oil spill, specially for moderate winds with complex topography. / La contaminación generada por los vertidos accidentales de petróleo puede ser reducida si se actúa y si se toman las decisiones adecuadas a tiempo. Las simulaciones numéricas de vertidos de petróleo permiten predecir la evolución de las manchas de crudo. En este trabajo, el objetivo principal era de mejorar la precisión y el rango de aplicación del código SIMOIL desarrollando e integrando al código un modelo de predicción de corrientes marinas en aguas costeras. Se han derivado las ecuaciones de aguas poco profundas en coordenadas generalizadas. Se han discretizado las ecuaciones y el código se implementó en FORTRAN 90. El modelo así como los métodos numéricos han sido validados con el estudio de flujos experimentales y numéricos de la bibliografía. Finalmente, la nueva versión de SIMOIL se aplicó con éxito a dos casos físicos de vertidos de crudo: • un vertido ficticio desde la monoboya de descarga de Repsol en el puerto de Tarragona • un vertido real, el mas grande ocurrido en el Este del mar Mediterráneo, consecuencia de la guerra en Líbano en julio de 2006. En ambos casos la nueva versión de SIMOIL proporcionó predicciones más precisas, especialmente para vientos moderados y topografías complejas.

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