Modifying milk fat composition to enhance its content of valuable fatty acids (FA) is required to meet the needs of a society which is becoming better informed about the relationship between diet and health. Manipulating the cow’s diet is an effective, natural way to modify the amount and composition of milk fat of cows. The two main factors that affect the cow’s diet concern management system (MS; pasture vs. confinement), and supplementation of diets with lipid supplements. Marine oils specifically are fed to enhance milk with n-3 long-chain polyunsaturated FA (n-3 LC-PUFA). The effects of source of marine lipid supplement (LS; fish oil vs. microalgae) in the cow’s diet and its interaction with MS on milk fat composition have not been studied. Thus, the main objective was to determine the interaction of MS and LS on milk FA profile and on expression of lipogenic genes in mammary, adipose and liver of lactating dairy cows. Compared with cows in confinement, grazing cows produced milk fat with lower content of unfavorable FA (12:0-16:0), while increasing the levels of beneficial FA including cis-9 18:1, 18:3 n-3 and conjugated 18:2. Feeding either fish oil or microalgae improved levels of n-3 LC-PUFA and reduced those of 16:0 in milk fat regardless of MS, but concurrently increased the level of other trans 18:1 isomers at the expense of trans-11 18:1. The reduced secretion of 12:0-16:0 in milk from grazing compared with confined cows was associated with lower mammary expression of lipogenic genes suggesting that part of the effect of MS on milk FA profile is mediated transcriptionally. The effect of LS on lipogenic gene expression was tissue specific with the greatest response to treatment observed in liver despite its minor role in lipogenesis in cattle relative to the mammary and adipose. Major conclusions were that milk produced in pasture systems has a more healthful FA profile than that of confinement systems, and that MS and LS have tissue specific effects on lipogenic gene expression in dairy cattle which have important effects on cow performance and healthfulness of the milk FA profile.

This diploma thesis deals with the problem of oil pollution of the marine environment caused by vessels. At the beginning of the thesis, the most important international agreements dealing with the protection of the marine environment and conventions regulating the cooperation of states in the elimination of the consequences of oil pollution are introduced. The thesis focuses mainly on the international conventions governing liability of an individual entity due to oil pollution of the oceans, but also briefly deals with the question of the state liability. The work analyses relevant US legislation, and compares this with an examination into the stance of the European Union and the Czech Republic with regards to this problem. In conclusion, some provisions of the international conventions are subjected to criticism and possible changes to the legislation are proposed.

No / Gas chromatography–mass spectrometry (GC–MS) and bulk carbon isotope determinations have been performed on samples (‘cemented organic residues’, charcoal, sediment and fire-cracked rock) excavated from 12 slab-lined pits from various locations in Arctic Norway to test the premise that these archaeological features were used for the extraction of oil from the blubber of marine mammals, such as seal, whale and walrus. A wide range of lipid compound classes were detected especially in the cemented organic residues and in the charcoal samples. The presence of long-chain unsaturated and isoprenoid fatty acids together with oxidation and thermal alteration products of unsaturated acids such as dicarboxylic acids, dihydroxyfatty acids and ω-(o-alkylphenyl)alkanoic acids suggests that these features were used for marine oil extraction at elevated temperatures. Notably the location of the hydroxyl groups in the dihydroxyfatty acids provides a record of the positional isomer of the precursor fatty acid and allows confirmation that 11-docosenoic (cetoleic) acid, the most abundant C22:1 isomer in marine oil, was a major component of the original lipid. Further information was provided by the presence of long-chain fatty acyl moieties in surviving triacylglycerols and the presence of cholesterol. A fungal metabolite, mycose (trehalose), was found in all samples apart from a fire-cracked rock and points to microbiological activity in the pits. Bulk isotope analysis conducted on the ‘cemented organic residues’ is consistent with modern reference samples of blubber and oil from seal and whale. These data provide clear analytical evidence of the function of slab-lined pits in the archaeological record and suggest widespread exploitation of marine mammals for producing oil for heating, lighting and myriad other uses in the past.

Chronic oil pollution or frequent small-scale oil discharges from vessel operations is an important source of marine oil pollution and considered a constant threat to marine and coastal environments. In Canada’s Pacific region, evidence of such illegal discharges has been gathered by the National Aerial Surveillance Program (NASP) from 1998 to 2007. We used this information to fit Generalized Linear Models (GLMs) for offshore waters and inshore waters and explore the relationships between oil spill occurrences and four predictor variables: shipping traffic densities for different vessel types, distance to shore, distance to port and density of small harbours. The best-fit models for both regions show that areas closer to shore and with higher density of small harbours have a higher probability of oil spill occurrences. However, only in inshore waters was shipping traffic significantly related with oil spill occurrences. Tug boats and oil tanker traffic show a significant positive relationship with oil spill observations, while carriers presented a negative association. Mapped results for offshore areas depicted the highest probability of oily discharges in Barkley Sound and at the entrance of the Juan de Fuca Strait; whereas in inshore waters, oil pollution hot spots were found in the vicinity of major commercial and tourist centres. These probability maps were used to identify Coastal and Marine Protected Areas (CMPAs) and Important Bird Areas (IBAs) more likely to be exposed to chronic oil pollution during a period of 10 years. Three areas were highlighted as the most vulnerable based on their likelihood of exposure and the sensitivity of the species they contain to oil pollution. These sites are the Tofino Mudflats, Barkley Sound, Scott Islands and the Sturgeon and Robert Banks, in the Fraser River delta. Our findings provide better understanding of the relationships between oil spill occurrences and vessel operations and help us identify likely oil pollution hot spots and sites particularly vulnerable to this stressor in Canada’s Pacific region. This information can be useful to NASP in improving its efficiency and in targeting monitoring efforts to troublesome areas. Additionally, this research contributes to regional studies that focus on analyzing the distribution of anthropogenic stressors from sea-based activities in British Columbia. Finally, we highlight the importance of collecting accurate data to properly model the probability of oil spill occurrences and encourage future research aiming to better understand and ultimately reduce the chronic release of pollutants from shipping activities into the marine environment.

Made available in DSpace on 2015-03-13T17:08:24Z (GMT). No. of bitstreams: 1 RenataCLA.pdf: 1406363 bytes, checksum: c23d0993b7ed86a192397c6e7f6d9580 (MD5) Previous issue date: 2004-10-14 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Objective to establish a methodology for the oil spill monitoring on the sea surface, located at the Submerged Exploration Area of the Polo Region of Guamar?, in the State of Rio Grande do Norte, using orbital images of Synthetic Aperture Radar (SAR integrated with meteoceanographycs products. This methodology was applied in the following stages: (1) the creation of a base map of the Exploration Area; (2) the processing of NOAA/AVHRR and ERS-2 images for generation of meteoceanographycs products; (3) the processing of RADARSAT-1 images for monitoring of oil spills; (4) the integration of RADARSAT-1 images with NOAA/AVHRR and ERS-2 image products; and (5) the structuring of a data base. The Integration of RADARSAT-1 image of the Potiguar Basin of day 21.05.99 with the base map of the Exploration Area of the Polo Region of Guamar? for the identification of the probable sources of the oil spots, was used successfully in the detention of the probable spot of oil detected next to the exit to the submarine emissary in the Exploration Area of the Polo Region of Guamar?. To support the integration of RADARSAT-1 images with NOAA/AVHRR and ERS-2 image products, a methodology was developed for the classification of oil spills identified by RADARSAT-1 images. For this, the following algorithms of classification not supervised were tested: K-means, Fuzzy k-means and Isodata. These algorithms are part of the PCI Geomatics software, which was used for the filtering of RADARSAT-1 images. For validation of the results, the oil spills submitted to the unsupervised classification were compared to the results of the Semivariogram Textural Classifier (STC). The mentioned classifier was developed especially for oil spill classification purposes and requires PCI software for the whole processing of RADARSAT-1 images. After all, the results of the classifications were analyzed through Visual Analysis; Calculation of Proportionality of Largeness and Analysis Statistics. Amongst the three algorithms of classifications tested, it was noted that there were no significant alterations in relation to the spills classified with the STC, in all of the analyses taken into consideration. Therefore, considering all the procedures, it has been shown that the described methodology can be successfully applied using the unsupervised classifiers tested, resulting in a decrease of time in the identification and classification processing of oil spills, if compared with the utilization of the STC classifier / Objetiva o estabelecimento de uma metodologia para monitoramento de derramamento de ?leo no mar, na ?rea de Explora??o Submersa do P?lo de Guamar?, no Estado do Rio Grande do Norte, utilizando imagens orbitais de radares de abertura sint?tica (SAR) integradas aos produtos meteoceanogr?ficos. A aplica??o do modelo metodol?gico foi composto pelas seguintes etapas: (1) a cria??o de um mapa base da ?rea de Explora??o; (2) o processamento de imagens NOAA/AVHRR e ERS-2 para gera??o de produtos meteoceanogr?ficos; (3) o processamento de imagens RADARSAT-1 para monitoramento das manchas de ?leo; (4) a integra??o da imagem RADARSAT-1 com os produtos de imagens NOAA/AVHRR e ERS-2; e (5) a estrutura??o de um banco de dados. A Integra??o da imagem RADARSAT-1 da Bacia Potiguar do dia 21.05.99 com o mapa base da ?rea de Explora??o do P?lo de Guamar? para a identifica??o das prov?veis fontes das manchas de ?leo, foi utilizada com sucesso na detec??o da prov?vel mancha de ?leo detectada pr?xima ? sa?da do emiss?rio submarino na ?rea de Explora??o do P?lo de Guamar?. Para subsidiar a integra??o da imagem RADARSAT-1 com os produtos de imagens NOAA/AVHRR e ERS-2, desenvolveu-se uma metodologia para a classifica??o das manchas de ?leo identificadas em imagens RADARSAT-1. Nesta metodologia, testou-se os seguintes algor?tmos de classifica??o n?o-supervisionada: K-means, Fuzzy k-means e Isodata, que s?o parte integrante do software PCI Geomatics, o qual foi utilizado para a filtragem das imagens RADARSAT-1. Para a avalia??o dos resultados, as manchas de ?leo submetidas ? classifica??o n?o-supervisionada foram comparadas aos resultados do Classificador Textural por Semivariograma (STC), o qual foi desenvolvido especificamente para esta finalidade e requer a utiliza??o do software PCI Geomatics para efetuar parte do processamento das imagens RADARSAT-1. Por fim, os resultados das classifica??es foram analisados atrav?s de An?lise Visual; C?lculo de Proporcionalidade de Grandezas e An?lise Estat?stica. Dentre os tr?s algoritmos de classifica??o testados n?o houve significantes altera??es em rela??o as manchas classificadas pelo STC, em nenhuma das an?lises efetuadas. Os procedimentos adotados demonstraram que a metodologia descrita aqui poder? ser aplicada com sucesso, utilizando os classificadores n?o supervisionados testados, o que acarretaria em diminui??o de tempo no processo de identifica??o e classifica??o de manchas de ?leo, em compara??o ? utiliza??o do classificador STC

Canada has become increasingly economically dependent on the exportation of bitumen to trans-oceanic international markets. As the export of Alberta bitumen from ports located in British Columbia increases, oil spill response and readiness measures become increasingly important. Although the frequency of ship-source oil spills has dramatically declined over the past several decades, they remain environmentally devastating when they occur. In the event of a marine spill, great lengths of shoreline are at risk of being contaminated. Once ashore, oil can persist for decades if shoreline hydraulic conditions are correct and remediation does not occur. Most commonly transported oils (e.g., fuel oils, Bunker C, crude oil, etc.) have been thoroughly studied, and their fate and behaviour in the event of a marine spill is well understood. In contrast, because diluted bitumen has been historically traded in relatively low quantities and has almost no spill history, there is a sizable knowledge gap regarding its effects and behaviour in both the marine environment and on coastal shorelines. The intent of this thesis was to develop a classification scheme to identify marine shorelines of high and low diluted bitumen (dilbit) retention for southeastern Vancouver Island, British Columbia. This study builds upon the outcome of former laboratory bench top dilbit and sediment research known as Bitumen Experiments (Bit_Ex). Bit_Ex investigated dilbit penetration and retention in six engineered sediment classifications ranging from coarse sand to very large pebble in accordance with the Wentworth Classification scheme. This research used Bit_Ex findings to predict dilbit retention in poorly sorted in-situ beach sediments found on shorelines representative of the southern coast of Vancouver Island, British Columbia, Canada. Field and laboratory measurements were conducted to document the occurrence of in-situ shoreline sediments and hydraulic conditions and were used to predict dilbit retention by comparing such characteristics between Bit_Ex and unconsolidated in-situ beach sediments. Saturated hydraulic conductivity (Ks) was measured using a double-ring constant-head infiltrometer. Measured Ks values were then compared to predicted Ks values generated by five semi-empirical Ks equations. A modified version of the Hazen Approximation was selected as the most appropriate. Using measured and calculated metrics, sediments were grouped as having either low or high dilbit retention. When sediments were analysed as homogenous samples, the experimental results suggested two of ten shorelines were composed of a combination of low and high retention sections, while the remaining eight sites were of low retention. Upon the isolation of coarse surface strata, results indicated two shorelines were entirely veneered with high retention sediments, and four shorelines were a combination of high and low retention. The residual four shorelines were found to be entirely composed of low retention sediments. The results illuminate the importance of shoreline stratification when predicting shoreline oil retention. This characteristic is a factor that current shoreline oil retention mapping techniques do not adequately consider. Additionally, the findings suggest that while sediments indicative of retaining weathered dilbit are relatively uncommon within Juan de Fuca and Harro Straits, high retention unweathered dilbit sediments are more common. / Graduate / 2018-06-26