Background: Endurance running is known to be a prevalent sport, due to well-understood health benefits. Ultramarathon running, particularly in master athletes, has been increasingly popular. Various parameters of an individual's ability to participate in numerous such events have been explored. The performance trends of such seasoned runners have been of interest to identify trends that could influence participation and running career longevity. Aim To identify performance trends of seasoned ultramarathon runners across their Two Oceans Ultramarathon running careers. Specific Objectives The specific objectives were to 1) describe the profile of seasoned ultramarathon runners who have completed 20 or more Two Oceans Ultramarathon races, including sex, number of ultramarathons completed, medal category of peak performance and age at debut Two Oceans Ultramarathon; 2) to determine average performance, peak performance, worst performance and the pattern of improvement or decline in performance in seasoned ultramarathon runners over 20 years of race participation; 3) to determine differences in factors that may influence performance trends, such as sex, number of ultramarathons completed, medal category of peak performance and age at debut Two Oceans Ultramarathon; and 4) to determine the variation in ultramarathon performance based on the sex, number of ultramarathons completed, medal category of peak performance and age at debut Two Oceans Ultramarathon. Methods Data from 625 runners who completed 20 or more Two Oceans Ultramarathons were extracted from a publicly available website (www.twooceansmarathon.org). Finish times across their running careers were used to establish average race speeds, peak and worst performances, changes in performance over time, and coefficients of variation in performance. Groups were compared according to a) sex, b) number of Two Oceans Ultramarathons completed (20 or more than 20), c) age category of debut race, and d) medal category of peak performance. Results The finishing times and race speed results showed that males ran significantly faster than females across their 20 year Two Oceans Ultramarathon running careers (p=0.00001). Runners who completed more than 20 races had faster finishing times and race paces than those who ran 20 Two Oceans Ultramarathons (p=0.00001). When performances of the participants were analysed according to age categories, the youngest age group, namely 16-19, had the fastest average finishing times across 20 years of racing (p=0.00002). Peak and worst performances showed that best personal efforts were attained in the first quarter of the Two Oceans Ultramarathon career, and worst race performances toward the end of these running careers. It was observed that as running careers progressed over time, the groups compared showed a pattern of performance convergence as differences in finishing times and running speeds decreased. Discussion and Conclusion The findings of this study suggest that a decline in performance over time is a natural and inevitable progression of a running career. Peak performances are usually acquired within the first few years of running careers. Participation trends as well as improved performances of master runners has shown that advanced age may be favourable in successful long-term ultramarathon running. This study identified a unique cohort of athletes who have consistently maintained ultramarathon running for 20 or more years. There is an opportunity for more detailed investigation of factors contributing to the longevity of their running careers, with the goal of promoting continuity in endurance running participation and physical activity at large.

<p> The clay mineralogy and elemental chemistry of soil and sediment samples from a small area of the Canadian Arctic Archipelago were examined. The importance of mineral-water reactions and the distinctive features of the geochemical cycle in polar regions are discussed. New data are presented for Hg, Au and Pd in near-shore sediments. In the case of Au and Pd the study was extended to include pelagic sediments from other oceans, and these results are discussed in an appendix.</p> / Thesis / Master of Science (MSc)

The purpose of this thesis is to establish possible changes in the CI/Br ratio of ancient oceans over the past 2 x 10 9 years. Variations in the Cl/Br ratio of carbonate rocks are used to indicate these changes. A secondary objective of this thesis is to determine the distribution patterns of F in limestones and dolomites. Variations in the F content of dolomites are shown to be related to environment of deposition and can be used to establish tho genesis of dolomite. The contents of the thesis include; 1) a comprehensive review of the pertinent literature, 2) a discussion of the evolution of the Cl/Br ratio of the ocean. 3) application of F in paleoenvironmental reconstruction, and 4) suggestions for further research. / Thesis / Doctor of Philosophy (PhD)

Les diatomées (Stramenopiles, Bacillariophyceae) jouent un rôle important sur le plan écologique et sont l'un des groupes phytoplanctoniques les plus divers, avec environ 1800 espèces planctoniques estimées. Bien que largement étudiées, leurs modèles de diversité et de distribution biogéographique ne sont pas bien connus. L'avènement du séquençage de l'ADN à haut débit a révolutionné les études de biodiversité moléculaire facilitant la compréhension de la biogéographie, de la structure des communautés et des processus écologiques. Les deux principaux objectifs de cette thèse sont (1) d'enquêter sur les modèles de la biodiversité mondiale et la structure des communautés de diatomées planctoniques à travers les océans du monde, et (2) de comprendre les mécanismes et processus déterminants la structure de la communauté. Cette thèse présente également une première tentative de discerner la répartition des espèces rares dans les communautés de protistes. L'étude a été réalisée en utilisant les données de metabarcoding générées à partir des échantillons biologiques et des données environnementales associées recueillies au cours de la campagne Tara Oceans (2009-2013), une circumnavigation globale couvrant toutes les principales provinces océaniques. Le matériel d’étude pour cette thèse est constitué d’un total de 12 millions de séquences de la sous unité V9 du 18S ribosomal (barcode), récoltées à partir de 46 stations soit 293 échantillons. Basée sur 63371 metabarcodes de diatomées uniques, cette étude présente une évaluation approfondie de la distribution mondiale des diatomées et de leur diversité. Les analyses révèlent des faits marquants liées à la biogéographie des diatomées, par exemple une nouvelle estimation du nombre total d'espèces de diatomées planctoniques, une diversité considérable inconnue, une diversité exceptionnellement élevée en haute mer, et des patrons de diversité complexes entre les provinces océaniques. La thèse examine ensuite les facteurs qui déterminent les modèles de bêta-diversité. Les résultats suggèrent que les diatomées sont des communautés structurées et réglementées par l'hétérogénéité de l'environnement et des processus spatiaux. Néanmoins, la majorité de la variation totale dans la composition de la communauté ne peut être expliquée ni par les facteurs environnementaux, ni par les distances spatiales, ce qui justifie les analyses futures se concentrant sur les interactions biologiques, les événements historiques, et d'autres facteurs qui ne sont pas considérés. La thèse décrit en outre une approche pour caractériser les clusters significativement associés de ribotypes concomitants. Enfin, une étude préliminaire de communautés de protistes fractionnées par taille révèle que la queue (de leurs distributions rang abondance) semble suivre un comportement en loi de puissance dans presque toutes les communautés de protistes. Cette observation peut indiquer un mécanisme universel potentiel qui peut expliquer l'organisation de communautés planctoniques marines. De façon générale, ce travail présent une perspective globale et complète de la distribution et de la diversité des diatomées dans les océans du monde. La thèse propose un cadre global pour l'évaluation de la diversité mondiale basée sur le metabarcoding, qui pourra être utilisé pour étudier la distribution et la diversité des autres lignées taxonomiques. Par conséquent, ce travail fournit un point de référence pour explorer comment les communautés microbiennes feront face à la variation des conditions environnementales. / Diatoms (Stramenopiles, Bacillariophyceae) are an ecologically important and one of the most diverse phytoplanktonic groups, with an estimated ~1,800 marine planktonic species. Although widely studied, their diversity and biogeographic distribution patterns are not well known. The advent of high-throughput DNA sequencing has revolutionized molecular biodiversity studies facilitating the understanding of biogeography, community assembly and ecological processes. The two major goals of this thesis are (1) to investigate global biodiversity patterns and structure of marine planktonic diatom communities across the world’s oceans, and (2) to understand the mechanisms and processes determining their community structure and assembly. This thesis also presents an initial attempt to discern the distribution of rare species in protist communities. The study was conducted using the metabarcoding data generated from the biological samples and associated environmental data collected during the Tara Oceans (2009-2013) global circumnavigation covering all major oceanic provinces. A total of ~12 million diatom V9-18S rDNA tags from 46 sampling stations, constituting 293 size fractionated samples represent the study material for the thesis. Using 63,371 unique diatom metabarcodes, this study presents an in-depth evaluation of global diatom distribution and diversity. The analyses study draw a number of revelations related to diatom biogeography, e.g. a new estimate of the total number of planktonic diatom species, a considerable unknown diversity, exceptionally high diversity in the open ocean, complex diversity patterns across oceanic provinces. The thesis then looks into the factors determining the beta-diversity patterns. The results suggest that diatoms represent biogeographically structured ecological communities regulated by both environmental heterogeneity and spatial processes. Nonetheless, the majority of the total variation in community composition remained unexplained by either the examined measured environmental factors or spatial distances, which warrants future analyses focusing on biological interactions, historical events, and other factors that are not considered. The thesis further outlines an approach to characterize significantly associated clusters of co-occurring ribotypes. Finally, a preliminary study of size-fractionated protistan communities reveals that the tail (of their rank-abundance distributions) appears to follow a power-law behavior in almost all protistan communities. This observation may indicate a potential universal mechanism which can explain the organization of marine planktonic communities. In general, this work has presented a global comprehensive perspective on diatom distribution and diversity in the world’s oceans. The thesis offers an overall framework for metabarcoding-based global diversity assessments which in turn can be employed to study distribution and diversity of other taxonomic lineages. Consequently, this work provides a reference point to explore how microbial communities will respond/change in response to environmental conditions.

La métagénomique vise à étudier le contenu génétique et génomique d'un échantillon provenant d'un environnement naturel. Cette discipline récente s'attache à étudier les génomes de différents organismes provenant d'un même milieu. La métagénomique pose de nouvelles questions, tant d'un point de vue biologique qu'informatique. Les masses de données générées par les études métagénomiques et la complexité des milieux étudiés, nécessitent de développer de nouvelles structures de données et de nouveaux algorithmes dédiés. Parmi les différentes approches existantes en métagénomique, la métagénomique comparative consiste à comparer plusieurs métagénomes afin d'en connaître les divers degrés de similarité. Lorsque cette comparaison se base uniquement sur le contenu brut des échantillons, sans faire appel à des connaissances externes, on parle de métagénomique comparative de novo. L'objectif des travaux que nous proposons est de développer une méthode permettant d'extraire les séquences similaires de deux jeux de données métagénomiques, où chaque jeu peut être composé de centaines de millions de courtes séquences. La comparaison proposée consiste à identifier les séquences d'un premier jeu similaires à au moins une séquence d'un second jeu. Afin d'être rapide et économe en mémoire, l'implémentation de notre méthode a nécessité la conception d'une nouvelle structure d'indexation, basée sur le filtre de bloom. Le logiciel final, nommé Compareads, a une consommation mémoire faible (de l'ordre de quelques go) et peut calculer l'intersection de deux échantillons de 100 millions de séquences chacun en une dizaine d'heures. Notre méthode est une heuristique qui génère un faible taux de faux positifs. Le logiciel Compareads est dédié à l'analyse de grands jeux de données métagénomiques. À l'heure actuelle, il est le seul outil capable de comparer de tels jeux. Compareads a été appliqué sur plusieurs projets métagénomiques. Notre outil produit des résultats robustes, biologiquement exploitables et en accord avec diverses méthodes fondamentalement différentes. Il est actuellement utilisé de manière intensive sur les échantillons provenant de l'expédition tara oceans. Sur ce projet, notre méthode à permis de mettre en évidence que les grands systèmes océaniques influent sur la répartition globale des micro-organismes marins. / Metagenomics studies overall genomic information of multiple organisms coming from the same biotope. The information is generally provided by next generation sequencing technologies (NGS). Typical data are samples of short reads (i.e. reads of few hundred base pairs). To study such metagenomics information, we developed an original method for extracting similarities between two samples of reads. More precisely, this approach locates the set of common reads present in two samples. In order to fit with current memory capacities and to be time efficient, we used a modified Bloom filter data structure. Finding the common reads between multiple samples and crossing this information with the location of samples leads to visualize some biological processes like ubiquitous species or effect of water stream caring some species. Finally, the tool can also be used as a filter on metagenomics datas to remove for example only one specie. Our software, Compareads, is actually used on the Tara Oceans project where it shows that global dynamic of oceans seems to play a part on the dispersion of marine microorganisms.

The strategic concept of "blue oceans" is currently undoubtedly one of the most interesting and most often talked strategic concepts. The thesis is therefore deals with the development of this strategic concept at the time and on the basis of previous papers of the authors in which were introduced tools and frameworks that later became part of the blue ocean strategy concept. The thesis also deals with other publications that the idea of the concept uses in own frames or in some way continues to build upon it. Further a description of the whole strategic concept is presented with each of analytical framework and tool with emphasis on additional context and findings of the section on the recent development of the concept. A key part of the thesis is the application of the concept to the three services - Knihovnička.cz Prezi and the Steam and evavulation of these tools with emphasis to the conclusions that have been made in the recent development of the strategic concept of "blue oceans" and its application.

Philosophiae Doctor - PhD / Ocean Governance in South Africa has gained momentum over the last decade with the publication of the Green and White Papers on the National Environmental Management of the Ocean in 2012 and 2014, and the promulgation of the Marine Spatial Planning Act in 2019. Parallel to this South Africa developed and implemented the Operation Phakisa Ocean Economy Development Programme and declared a network of twenty Marine Protected Areas. The timing of this study over the last five years allowed the opportunity to undertake a detailed study of the Ocean Governance Policy Development and Implementation as the formulation of the policy and its early implementation unfolded. The Study is primarily based on interpretation of the Green and White Papers as the primary and directed ocean governance policies produced by the Government of South African and the National Department of Environmental Affairs. It places these most recent specific ocean environmental policies in the context of the many other environmental policies that exits in the country.

In this thesis three independent studies of tidal dynamics have been pesented. The first is an analytical study of continental shelf tides forced at the ocean boundary. Earlier studies have shown that the response for a sloping shelf and a flat shelf differ and that the response for a flat shelf changes when tides are incident at an angle. Other studies considered a sloping shelf but they did not take into account a possible non-zero depth at a coastal wall. This study shows that the effects of a sloping shelf, a coastal wall and obliquely incident tides an all significantly modify the response on the shelf. The modification increases with the width of the shelf, and in a wide shelf scenario, near resonance, it greatly modifies the response. Secondly, the Princeton Ocean Model in barotropic mode along with a tracer transport module has been used to study the tides of Sydney Harbour. The tidally induced residual circulation due to the semi-diurnal tide consists of a series of recirculating gyres which are due to the interaction of flow with topography. This study shows that in the harbour it is the Lagrangian residual velocity not the Eulerian residual velocity which determines the net transport of material over a tidal cycle. In addition, the flushing time of the harbour varies significantly in space, and the tidal mixing is restricted in the vicinity of the entrance. The third is a theoretical study of forced oscillations in a rotating, flat-bottomed, circular basin. This study shows that the direction of propagation of waves in a basin depends on the ratio of its radius to depth. At each latitude there is a critical value of this ratio and this value decreases with increase in latitude. Beyond this value, waves start to propagate around the basin in the opposite direction to the earth ???s rotation (clockwise in the northern hemisphere and anti-clockwise in the southern hemisphere).The presence of friction increases this critical value which shows that friction plays an important role in determining the response.

Doctor of Philosophy(PhD) / It is only in recent decades that marine scientific research has begun to reveal the true physical characteristics and resource potential of the open ocean and deep seabed beyond national jurisdiction. A combination of factors such as the depletion of inshore fish stocks and an increase in global maritime trade has led to greater usage of the vast maritime area beyond the territorial sea and exclusive economic zone limits of the coastal states. Human activities in this area of the ocean, which covers approximately 50% of the world’s surface, have expanded to include bioprospecting, exploration for deep seabed minerals, more sophisticated marine scientific research and deep sea tourism. This rise in human activities beyond the offshore zones of coastal states poses actual and potential threats to the physical characteristics and biodiversity of the open ocean and deep sea environments. Arbitrary human intrusions into this largely unexplored marine domain have the potential to harm the intricate links between complex marine ecosystems and to erode components of marine biodiversity. This thesis examines the global and regional provisions which have been put in place to regulate the environmental impacts of human activities that occur beyond national jurisdiction. An analysis of these instruments and their implementation reveals that the current international law framework provides only minimal levels of protection for the marine environment beyond national jurisdiction. It explores several options based on the 1982 United Nations Convention on the Law of the Sea (LOSC) and the 1992 Convention on Biological Diversity (CBD) to establish a cohesive environmental protection system for the marine environment beyond national jurisdiction.

As part of the sustainable management of the Port of Saint John there is a critical need to maintain sufficient under keel clearance for the various container and cruise ship traffic in and out of the harbour. Because of high and variable sedimentation rates, annual maintenance dredging is necessary and causes economic concerns for the Port. Therefore to better predict future dredging volumes and hence improve the budgeting process for the Port of Saint John, the estuarine circulation of the harbour has been analysed to better quantify the relative importance of the offshore sediments that contribute to the high dredging volumes in the Saint John harbour. The Port of Saint John lies at the mouth of the Saint John River on the north side of the macrotidal Bay of Fundy. Because of this, the harbour sedimentation is influenced by two major sources of siltation: the Saint John River and the Bay of Fundy. The sediment flux from the river is strongly modulated by the seasonal variations in river discharge. In the Bay of Fundy, there is significant resuspension of offshore marine sediments. To better understand this complex interaction between the fresh water flow and the tidal inflow of salt water, high density oceanographic surveys have been conducted at four different river discharge periods. In order to quantitatively analyse the mixing of the fresh and salt water in the harbour channels, high density ADCP currents and CTD measurements were acquired along main longitudinal axis of the Main Harbour channel and Courtenay Bay over four tidal cycles. By imaging the 200kHz acoustic volume backscatter within the water column, the appearance of interfacial waves at the pycnocline can be examined. The optical backscatter sensor provided observations used to estimate suspended sediment concentrations. A cross-sectional analysis of the flow at a location 700m south and seaward of the Rodney bay terminal in the Main Channel revealed that regardless of the river discharge rate, the interfacial waves are best developed on the rising tide. However, during the Spring freshet the interfacial waves are also developed at high tide, low tide and falling tide. Examination of the timing and location of the interfacial waves are important because they influence the nature of sediment transport in the Main Harbour Channel. During high river discharge periods, the sediment concentration and volume flux estimates indicate that the river is the main source of sediments. For the low river discharge periods, the observations suggest that the possible source of suspended sediments observed in the lower saline layer are either from outside of the harbour or bottom sediments being resuspended on the rising tide.