Tesis sobre el tema "Marine fishes – North Sea"
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Leary, Arianne Ella. "Effects of the Deepwater Horizon Oil Spill on Deep Sea Fishes". UNF Digital Commons, 2015. http://digitalcommons.unf.edu/etd/566.
Texto completoBaudron, Alan Ronan. "Length-based modelling of North Sea fish growth". Thesis, University of Aberdeen, 2011. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=192287.
Texto completoO'Sullivan, Martha. "Population structure of demersal fish species in the north eastern Atlantic". Thesis, Available from the University of Aberdeen Library and Historic Collections Digital Resources. Restricted: no access until Dec. 31, 2010. Online version available for University members only until June 2, 2011, 2009. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=26063.
Texto completoBuch, Tanja B. "Spatial structure of North Sea fishes : theory and application to abundance estimation". Thesis, University of Aberdeen, 2018. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=237000.
Texto completoKerby, Tina. "UK fisheries, climate change and North Sea fishes : a long-term perspective". Thesis, University of East Anglia, 2013. https://ueaeprints.uea.ac.uk/47987/.
Texto completoMartínez, Iñigo. "Demersal fish assemblages around sea bed features : Buzzard oil & gas field platform in the North Sea and Jones Bank, Celtic Sea". Thesis, University of Aberdeen, 2011. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=183828.
Texto completoMair, Angus. "Investigation into a prominent 38 kHz scattering layer in the North Sea /". St Andrews, 2008. http://hdl.handle.net/10023/490.
Texto completoCasazza, Tara L. "Community structure and diets of fishes associated with pelagic Sargassum and open-water habitats off North Carolina". View electronic thesis, 2008. http://dl.uncw.edu/etd/2008-3/casazzat/taracasazza.pdf.
Texto completoCheung, Wai Lung. "Vulnerability of marine fishes to fishing : from global overview to the northern South China Sea". Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/31272.
Texto completoScience, Faculty of
Resources, Environment and Sustainability (IRES), Institute for
Graduate
Allsop, Timothy. "Early compaction history of marine siliciclastic sediments". Thesis, Durham University, 1994. http://etheses.dur.ac.uk/5675/.
Texto completoSpeckman, Suzann Gail. "Characterizing fish schools in relation to the marine environment and their use by seabirds in lower Cook Inlet, Alaska /". Thesis, Connect to this title online; UW restricted, 2004. http://hdl.handle.net/1773/5301.
Texto completoAboim, Maria Ana. "Population genetics and evolutionary history of some deep-sea demersal fishes from the Azores, North Atlantic". Thesis, University of Southampton, 2005. https://eprints.soton.ac.uk/17742/.
Texto completoIngram, Caroline S. "Ostracod palaeoecology and biogeochemistry of marine and estuarine interglacial deposits in North West Europe". Thesis, Bangor University, 1999. https://research.bangor.ac.uk/portal/en/theses/ostracod-palaeoecology-and-biogeochemistry-of-marine-and-estuarine-interglacial-deposits-in-north-west-europe(4cd7fd25-815b-4e1d-aebb-cada60a3d9b4).html.
Texto completoGypens, Nathalie. "Modélisation des efflorescences algales et des cycles du C, N, P et Si dans l'écosystème eutrophisé de la mer du Nord". Doctoral thesis, Universite Libre de Bruxelles, 2006. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210778.
Texto completoLe modèle validé a ensuite été utilisé pour étudier le fonctionnement de l’écosystème et les cycles biogéochimiques associés. Plus précisément, les bilans de carbone et de nutriments réalisés sur base des flux biologiques modélisés ont montré que l’écosystème de la BCZ, dominé par les efflorescences de Phaeocystis, se caractérise par une faible efficience trophique, une faible capacité de rétention/élimination des apports de nutriments d’origine anthropique et une faible capacité d’absorption du CO2 atmosphérique. Des scénarios annulant tour à tour l’activité biologique et les apports de carbone par les rivières ont permis de déterminer les rôles respectifs de la température, des processus biologiques et des apports de nutriments et de carbone par les rivières dans l’évolution saisonnière de la pCO2 des eaux de surface.
L’effet combiné des apports anthropiques de nutriments et des conditions météorologiques locales (débit, vent, température) a été étudié sur base d’une simulation effectuée pour la période contemporaine (1989-2003) en utilisant les forçages réels mesurés. La comparaison visuelle des simulations et des observations montre que, si le modèle est parfaitement capable de reproduire les successions phytoplanctoniques, il est par contre moins performant en ce qui concerne la reproduction des signaux extrêmes. Il apparaît donc que l’échelle de temps (mensuelle) utilisée pour décrire la variabilité des forçages est trop longue et ne permet pas de capter les variations hydrologiques à court terme résultant du vent et de la marée.
De manière à mieux comprendre le lien entre les activités humaines sur le bassin versant et l’eutrophisation des zones côtières, le modèle MIRO a été couplé aux sorties du modèle de rivière RIVERSTRAHLER appliqué à la Seine et à l’Escaut sur une période de 50 ans (1950-1998). Les résultats obtenus montrent que l’importance des efflorescences de diatomées est conditionnée par les apports de PO4, alors que l’importance des Phaeocystis est directement liée à l’importance des apports de NO3. Un bilan établi pour la BCZ montre que plus de 50% des apports annuels de N et 60% des apports annuels de P proviennent des eaux Atlantiques et pointe l‘importance des apports de la Seine pour l’enrichissement de la BCZ.
Différents scénarios de réduction des apports de nutriments provenant des rivières ont été réalisés afin de cibler le ou les nutriments à diminuer prioritairement pour réduire les efflorescences de Phaeocystis. Les résultats montrent que, dans les conditions actuelles, seule une réduction des apports de NO3 prédit une diminution des efflorescences de Phaeocystis. De plus, pour avoir un abattement significatif de ces efflorescences, il est nécessaire d’agir de manière conjointe sur les apports de la Seine et de l’Escaut.
En vue de l’implémentation du code MIRO dans un modèle 3D hydrodynamique et pour tenir compte de la variabilité spatiale des sédiments dans la zone étudiée, une paramétrisation des flux de nutriments à l’interface eau-sédiment a été recherchée sur base des résultats obtenus avec un modèle diagénétique analytique décrivant la dégradation de la matière organique et les cycles de l’azote et du phosphore dans les sédiments.
Doctorat en sciences, Spécialisation biologie animale
info:eu-repo/semantics/nonPublished
Fraser, Helen M. "Do fish predators in the North Sea live beyond their means is prey production sufficient to meet consumption? /". Thesis, Available from the University of Aberdeen Library and Historic Collections Digital Resources, 2008. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=24693.
Texto completoSchneider, von Deimling Jens [Verfasser]. "Hydroacoustic and geochemical traces of marine gas seepage in the North Sea / Jens Schneider von Deimling". Kiel : Universitätsbibliothek Kiel, 2010. http://d-nb.info/1019951257/34.
Texto completoBrewster, Jasmine Dawn. "Characterizing the diet and habitat niches of coastal fish populations in the Beaufort Sea Tarium Niryutait Marine Protected Area". Marine Ecological Progress Series, 2016. http://hdl.handle.net/1993/31961.
Texto completoFebruary 2017
Ali, Heba. "THE EFFECT OF DEPTH ON DEVELOPMENT AND SEXUAL DIMORPHISM OF THE SONIC SYSTEM IN DEEP SEA NEOBYTHITINE FISHES: THE UPPER CONTINENTAL SLOPE". VCU Scholars Compass, 2016. http://scholarscompass.vcu.edu/etd/4095.
Texto completoRoncari, Chiara. "Evaluation of microplastic content in faecal sample from hospitalized loggerhead sea turtles (Caretta caretta) of the North Adriatic Sea". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/20386/.
Texto completoTonino, Marco <1982>. "Transboundary governance of marine protected areas : a comparison of the North Adriatic and Wadden Sea case studies". Doctoral thesis, Università Ca' Foscari Venezia, 2014. http://hdl.handle.net/10579/4672.
Texto completoWeissbach, Astrid, Urban Tillmann y Catherine Legrand. "Allelopathic potential of the dinoflagellate Alexandrium tamarense on marine microbial communities". Linnéuniversitetet, Institutionen för naturvetenskap, NV, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-7332.
Texto completoAllelopathy among phytoplankton - a structuring force among phytoplankton
Colhoun, Elizabeth F. "Ecological Correlates of Community Structure in Seagrass-Associated Fishes in North Biscayne Bay and Port of Miami, Florida". Thesis, NSUWorks, 2018. https://nsuworks.nova.edu/occ_stuetd/466.
Texto completoCarew, Andrea M. E. "Oil pollution and the Newfoundland and Labrador fishery : current and potential threats for the conservation of commercial fisheries resources in Placentia Bay /". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ62375.pdf.
Texto completoMarshall, A. M. "Understanding shifts in body size distributions : a comparative study of the impacts of fishing and climate on North Sea demersal fishes". Thesis, University of Sheffield, 2017. http://etheses.whiterose.ac.uk/18955/.
Texto completoIlyina, Tatjana P. "The fate of persistent organic pollutants in the North Sea : multiple year model simulations of [gamma]-HCH, [alpha]-HCH and PCB 153 /". Berlin [u.a.] : Springer, 2007. http://www.loc.gov/catdir/toc/fy0710/2006939205.html.
Texto completoPhoel, William C. "Community structure of demersal fishes on the inshore U.S. Atlantic continental shelf: Cape Ann, MA. to Cape Fear, N.C. (United States, cluster analysis, Massachusetts, North Carolina)". W&M ScholarWorks, 1985. https://scholarworks.wm.edu/etd/1539616807.
Texto completoGebühr, Christina [Verfasser]. "Investigations on the ecology of the marine centric diatom Paralia sulcata at Helgoland Roads, North Sea, Germany / Christina Gebühr". Bremen : IRC-Library, Information Resource Center der Jacobs University Bremen, 2012. http://d-nb.info/1037011295/34.
Texto completoGuerin, Andrew James. "Marine communities of North Sea offshore platforms, and the use of stable isotopes to explore artificial reef food webs". Thesis, University of Southampton, 2009. https://eprints.soton.ac.uk/168947/.
Texto completoHolgate, Nicholas. "Geological characterisation of shallow marine-to-deltaic sandstone reservoir targets, Krossfjord and Fensfjord formations, Troll Field, Norwegian North Sea". Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/32135.
Texto completoNorris, Joel R. "Interannual variability in cloudiness, sea surface temperature, and atmospheric circulation over the midlatitude North Pacific during summer". Thesis, Connect to this title online; UW restricted, 1997. http://hdl.handle.net/1773/10050.
Texto completoDanis, Bruno. "Bioaccumulation and effects of polychlorinated biphenyls (PCBs) in the sea star Asterias rubens L". Doctoral thesis, Universite Libre de Bruxelles, 2004. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/211171.
Texto completoUbiquist, abundant and generally recognized as a good bioindicator species, the common NE Atlantic sea star Asterias rubens (L.) is an ecosystem-structuring species in the North Sea and was chosen as an experimental model. The present study focused on the characterization of PCB bioaccumulation in A. rubens exposed through different routes (seawater, food, sediments) and on subsequent biological responses, at immune and sucellular levels. The considered responses were respectively (i) the production of reactive oxyggen species (ROS) by sea stars amoebocytes, which constitutes the main line of defence of echinoderms against pathogenic challenges and (ii) the induction of a cytochrome P450 immunopositive protein (CYP1A IPP) which, in vertebrates, is involved in PCB detoxification.
Experimental exposures carried out have shown that A. rubens efficiently accumulates PCBs. Exposure concentrations were always adjusted to match those encountered in the field. PCB concentrations reached in sea stars during the experiments matched the values reported in field studies ;therefore our experimental protocol was found to accurately simulate actual field situations. Uptake kinetics were related to the planar conformation of the considered congeners :non-coplanar PCB uptake was described using saturation models, whereas coplanar PCBs (c-PCBs) were bioaccumulated according to bell-shaped kinetics. Non-coplanar congeners generally reached saturation concentrations whithin a few days or a few weeks, which means that sea stars can be used to pinpoint PCB contamination shortly after occurrence. On the other hand, c-PCB concentrations reached a peak followed by a sudden drop, indicating the probable occurrence of c-PCB-targeted metabolization processes in sea stars. Our experimental studies also demonstrated that seawater was by far the most efficient route for PCB uptake in sea stars and that even if PCB levels in seawater are extremely low compared to sediment-associated concentrations, seawater constitutes a non-negligible route for PCB uptake in marine invertebrates. Among the different body compartments, bodywall displayed the highest bioaccumulative potency and can therefore be considered as particularly interesting for field biomonitoring applications. Rectal caeca, which play a central role in digestion and excretion processes in sea stars, have also rised particular interest as results suggest these organs could be involved in the elimination of PCB 77 degradation products.
The field work carried out during the present study showed that PCB concentrations measured in A. rubens tissues reflect environmental levels of certain congeners. As it was the case in experimental conditions, A. rubens differentially accumulated PCB congeners according to their planarity. Strong relationships were found between concentrations measured in sediments and those determined in sea stars body wall for certain non-coplanar congeners (e.g. 118 and 138), thus allowing to consider A. rubens as a suitable bioindicator species for medium-chlorinated PCB congeners. On the other hand, sea stars appeared to be able to regulate -to a certain extent- their content in coplanar PCBs. This implies that (i) A. rubens cannot be strictly considered as an indicator organism for c-PCBs and (ii) c-PCBs probably affect essential aspects of sea star biology, potentially leading to deleterious effects.
The present study addressed effects of PCB exposure on A. rubens biology, in both experimental and field conditions. In experimental conditions, PCBs were found to significantly alter ROS production by sea stars amoebocytes. This alteration also occurred in a congener-specific way :c-PCBs were found to significantly affect, and probably impair sea stars immune system, whereas non-coplanar congeners had no effect. In the field, the PCB contribution to immunotoxicity could not be determined because none of our studies considered ROS production along with c-PCB concentration measurements. However, the levels of ROS production by sea stars amoebocytes measured in field and experimental conditions were found to potentially lead to altered immunity, and therefore to impair sea stars defence against pathogenic agents.
A specially designed ELISA was used to measure CYP1A IPP in experimental and field conditions. Experimental work has shown that the induction of this protein was related to PCB exposure in a congener-specific fashion :c-PCBs alone were found to strongly induce the production of CYP1A IPP according to a dose-dependent relationship. These results have highlighted many similarities between the dioxin-like responsiveness of CYP1A IPP induction in sea stars and that occurring in vertebrates. This strongly suggests similarities in the toxicity-triggering mechanism of dioxins and c-PCBs. In the field, CYP1A IPP induction was found to be significantly related to PCB levels determined in bottom sediments. It can thus be considered as a valuable biomarker. Further research is however needed to better characterize the influence of physico-chemical and physiological parameters on CYP1A induction to refine the interpretation of the information gathered via this biomarker.
Results obtained in our study have lead to questionning international regulations applying to PCB biomonitoring in the marine environment. For instance, we strongly suggest that the selection of congeners to be systematically considered should be revised to include c-PCBs. Indeed, in our experiments PCB toxicity was almost always attributable to the sole c-congeners. Historically, determination of c-PCB concentrations was extremely difficult due to analytical limitations ;however, nowadays, these problems have been overcome and do no more justify their exclusion from monitoring studies.
Although A. rubens appeared to be quite resistant to PCB contamination, levels measured in sea stars from the southern North Sea can possibly affect their immune and endocrine systems in a subtle way, but with relatively low risk for this species at the short-term. However, this does not mean that other species in this region undergo similarly low risks, or that sea star-structured ecosystems may not become affected in the long-term
Doctorat en sciences, Spécialisation biologie animale
info:eu-repo/semantics/nonPublished
Chiti, Bernardo. "Holocene fluvial and marine influences and settlement interactions in the lower Ribble Valley, Lancashire, U.K". Thesis, University of Stirling, 2004. http://hdl.handle.net/1893/1805.
Texto completoKeeble, Kathryn. "Common drivers and indicators of large-scale changes in the community structure and function of three UK marine ecosystems : the Irish Sea, North Sea and Western English Channel". Thesis, University of Newcastle Upon Tyne, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.577148.
Texto completoFortuna, Caterina Maria. "Ecology and conservation of bottlenose dolphins (Tursiops truncatus) in the north-eastern Adriatic Sea". Thesis, St Andrews, 2007. http://hdl.handle.net/10023/157.
Texto completoNooner, Scott L. "Gravity changes associated with underground injections of CO₂ at the Sleipner storage reservoir in the North Sea, and other marine geodetic studies /". Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2005. http://wwwlib.umi.com/cr/ucsd/fullcit?p3171110.
Texto completoBos, Ryan P. "The Association between Stomach Fullness and Vertical Migration Behavior in Deep-Pelagic Crustaceans and Fishes in the Gulf of Mexico, with Notes on Microplastic Ingestion". Thesis, NSUWorks, 2019. https://nsuworks.nova.edu/occ_stuetd/502.
Texto completoBarbas, Ruthie E. "Tests of Reproductive Isolation Between the Fishes Fundulus heteroclitus and F. grandis". UNF Digital Commons, 2016. http://digitalcommons.unf.edu/etd/624.
Texto completoSimmons, Kayelyn Regina. "Evidence of the Enemy Release Hypothesis: Parasites of the Lionfish Complex (Pterios volitans and P. miles) in the Western North Atlantic, Gulf of Mexico, and Caribbean Sea". NSUWorks, 2014. http://nsuworks.nova.edu/occ_stuetd/2.
Texto completoWilson, Sarah Jane. "High resolution comparative palynostratigraphy and palaeoecology of oligocene sequences in the terrestrial basins of the Western British Isles and the marine North Sea basin". Thesis, University of Sheffield, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.527316.
Texto completoRay, Kacy Lyn. "Factors affecting Wilson's Plover (Charadrius wilsonia) demography and habitat use at Onslow Beach, Marine Corps Base Camp Lejeune, North Carolina". Thesis, Virginia Tech, 2011. http://hdl.handle.net/10919/30996.
Texto completoMaster of Science
Colmenero, Ginés Ana Isabel. "Towards biological and ecological knowledge of Lophius spp. in the NW Mediterranean Sea for a sustainable fishery". Doctoral thesis, Universitat de Barcelona, 2017. http://hdl.handle.net/10803/462032.
Texto completoEn el noroeste del mar Mediterráneo, las especies de rape Lophius budegassa Spinola, 1807 y Lophius piscatorius Linnaeus, 1758 se encuentran entre las especies demersales más valiosas sobre las cuales se efectúa una actividad pesquera importante. Ambas especies son capturadas generalmente en pesquerías mixtas de arrastre de fondo que operan en la plataforma continental y en el talud superior. Las descargas se componen principalmente de L. budegassa (86%) y un pequeño porcentaje de L. piscatorius (14%), y han aumentado en los últimos años debido al desarrollo de una pesca más dirigida, alcanzando 9,486 t y un valor de 65 millones de euros durante el período 2000-2016. Hasta la fecha, la Comisión Europea ha realizado evaluaciones de las poblaciones de L. budegassa que habitan las aguas del Mediterráneo, pero no se ha hecho ningún esfuerzo respecto a L. piscatorius. Atendiendo a la importancia comercial de estas especies, el objetivo de esta Tesis ha sido mejorar el conocimiento de los parámetros de la población de L. budegassa y L. piscatorius del noroeste del Mar Mediterráneo para determinar su estado de explotación y establecer una gestión efectiva. Para alcanzar dicho objetivo, se plantearon un conjunto de objetivos específicos: determinar su comportamiento y los mecanismos sensoriales para reducir los niveles de competencia ecológica; describir los parámetros reproductores para mejorar la comprensión del ciclo de vida; examinar las características morfológicas de los óvulos para identificar los huevos a partir de muestras de ictioplancton; proporcionar nuevos datos sobre la dinámica de la población, así como sobre la su estructura y las relaciones biométricas para modelar los stocks; explorar los indicadores de sostenibilidad para monitorear el estado de la población en relación con la explotación; y analizar la prevalencia del parásito microspordio Spraguea lophii para formular hipótesis sobre el estado de salud de la población de Lophius y los posibles efectos secundarios de infecciones graves en su morfología. Los resultados han demostrado que L. budegassa y L. piscatorius ocupan el mismo hábitat en el noroeste del Mediterráneo, si bien las diferencias observadas en sus parámetros del ciclo de vida apoyan la hipótesis de que ambas especies tienen diferentes estrategias ecológicas para disminuir la competencia entre ellas. De acuerdo con las diferencias encontradas, se recomienda realizar una gestión diferenciada para cada especie de Lophius en el noroeste del Mar Mediterráneo.
McArthur, Adam D. "Temporal and spatial relationships of syn-rift, deep-marine hangingwall stratigraphy : examples from the Upper Jurassic of the Inner Moray Firth and the Central North Sea". Thesis, University of Aberdeen, 2012. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=191932.
Texto completoWise, Matthew Geoffrey. "Iceberg-keel ploughmarks on the seafloor of Antarctic continental shelves and the North Falkland Basin : implications for palaeo-glaciology". Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/276147.
Texto completoCox, Tom, Tom Maris, Karline Soetart, Daniel Conley, Damme Stefan van, Patrick Meire, Jack J. Middelburg, Matthijs Vos y Eric Struyf. "A macro-tidal freshwater ecosystem recovering from hypereutrophication : the Schelde lease study". Universität Potsdam, 2009. http://opus.kobv.de/ubp/volltexte/2010/4518/.
Texto completoAstoreca, Rosa. "Study and application of the Inherent Optical Properties of coastal waters from the Phaeocystis-dominated Sounthern Bight of the North Sea". Doctoral thesis, Universite Libre de Bruxelles, 2007. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210646.
Texto completoThe area is characterised by a high spatio-temporal variability of IOPs due to the high dynamics of the area in terms of currents, salinity gradients and biological production. During spring the presence of P. globosa modulates the IOPs across all the area, the particle absorption is significantly higher than summer and there is no significant coast-offshore variability for phytoplankton and CDOM.
The design of chl a retrieval algorithms assumes negligible absorption of NAP and CDOM in the near infrared (NIR) and the use of a fixed value of specific phytoplankton absorption. It is shown that neglecting the NAP and CDOM absorption in the NIR will have a significant overestimation impact in retrieval of chl a. On the other hand, the specific phytoplankton absorption was found to be highly variable (0.015 „b 0.011 m2 mg chl a-1). Both results will affect directly the retrieved chl a. The spatial variability of CDOM was significant varying between 0.20-1.31 m-1 in the marine area and between 1.81-4.29 m-1 in the Scheldt estuary. CDOM was found to be related to salinity with conservative mixing within the Scheldt estuary and during some seasons in the BCZ, however deviations from conservative mixing suggest other inputs to the CDOM pool. Analyses of the spectral slope of the CDOM absorption curve revealed two main CDOM pools in the area, an allochthonous one delivered by the Scheldt estuary and an autochthonous one associated with the phytoplankton spring bloom decomposition. Algorithms for CDOM retrieval will be affected if the variability in the relation between CDOM and salinity is not taken into account.
The optical characterisation of diatoms and P. globosa from the BCZ in pure cultures revealed that the main differences in the phytoplankton absorption spectra were found at 467 and 500 nm corresponding to the absorption of the pigments chlorophyll c3 (chl c3) characteristic of P. globosa and fucoxanthin, respectively. Accordingly, both the absorption at 467 nm and the ratio 500/467 nm were successfully used to discriminate the two taxa in cultures and field samples. This latter indicator was not preserved in the reflectance signal due to degradation of the signal when passing from absorption to reflectance, and thus could not be used for algorithm development. The spectral feature at 467 nm was later used as the basis for the development of a flag-type algorithm to detect chl c3 using either absorption or water-leaving reflectance data. Also, the correlation between the algorithm¡¦s retrieved chl c3 and P. globosa cell number allowed the quantification of the bloom. The main findings of this thesis highlight the importance of the IOPs characterisation for the improvement and development of ocean colour retrieval algorithms in these highly complex waters.
Doctorat en Sciences
info:eu-repo/semantics/nonPublished
Meynier, Laureline. "Feeding ecology of the New Zealand sea lion (Phocarctos hookeri) : a thesis presented in partial fulfilment of the requirements for the degree of Doctor Philosophy in Zoology at Massey University, Palmerston North, New Zealand". Massey University, 2009. http://hdl.handle.net/10179/901.
Texto completoMoulins, Aurélie. "To the integrated approach and to the management of pelagic biodiversity inside a marine protected area : case of the cetacean populations in the Pelagos sanctuary (north-western Mediterranean sea)". Lyon 1, 2008. http://www.theses.fr/2008LYO10027.
Texto completoVirgili, Auriane. "Modelling distributions of rare marine species : the deep-diving cetaceans". Thesis, La Rochelle, 2018. http://www.theses.fr/2018LAROS003/document.
Texto completoDeep-diving cetaceans, sperm- and beaked whales Physeteridae, Kogiidae and Ziphiidae, are rare marine species. Due to their low densities, wide distribution ranges and limited presence at the water surface, visual surveys usually result in low sighting rates. This paucity of data challenges the modelling of their habitat, prerequisite for their conservation. Models have to cope with a great number of zeros that weakens the ability to make sound ecological inferences. Consequently, this thesis aimed at finding a methodology suitable for datasets with a large number of zeros, determining how environmental variables influence deep-diver distributions and predicting areas preferentially used by these species. By testing the predictive performance of various habitat models fitted to decreasing numbers of sightings, I selected the most suitable model and determined that at least 50 sightings were needed to provide reliable predictions. However, individual surveys can rarely provide sufficient deep-diver sightings thus I merged many visual survey datasets to produce the first basin-wide deep-diver density maps in the North Atlantic Ocean and the Mediterranean Sea. Highest densities were predicted in waters from 1500-4000 m deep and close to thermal fronts ; hotspots were predicted along the continental slopes, particularly in the western North Atlantic Ocean. In addition, a model transferability analysis highlighted that habitat drivers selected by the models varied between contrasted large ecosystems. Finally, I discussed challenges related to statistical modelling applied to rare species and the management applications of this thesis
Alappat, Linto [Verfasser]. "Application of OSL dating on coastal sediments : case studies from shallow marine sediments of Southern North Sea, Germany, and coastal sub-surface and surface sediments from south India / Linto Alappat". Berlin : Freie Universität Berlin, 2011. http://d-nb.info/1025938771/34.
Texto completoHammill, Allison L. "Effects of Localized NAO, ONI (ENSO) and AMO Events on Reproductive Patterns in Loggerhead (Caretta caretta) Sea Turtles in Broward County, FL, USA". NSUWorks, 2013. http://nsuworks.nova.edu/occ_stuetd/135.
Texto completo