Thesis (M.S.)--Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1999. / Includes bibliographical references (leaves 23-30).

Thesis (Ph. D.)--University of Wisconsin--Madison, 1985. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 170-188).

BEZERRA JÚNIIOR, Antônio Valdenísio. Análise das provas do exame da OAB e do ENADE dos Cursos de Direito do ano de 2012 à luz da taxonomia dos objetivos educacionais de Benjamin Bloom. 2016. 80f. Dissertação (Mestrado) – Universidade Federal do Ceará, Programa de Pós-graduação em Educação Brasileira, Fortaleza (CE), 2016. / Submitted by Gustavo Daher (gdaherufc@hotmail.com) on 2017-01-06T15:33:42Z No. of bitstreams: 1 2016_dis_avbezerrajunior.pdf: 1765886 bytes, checksum: 6d7d4cc59cc428f0bd730303a986bdea (MD5) / Rejected by Maria Josineide Góis (josineide@ufc.br), reason: on 2017-01-06T16:13:54Z (GMT) / Submitted by Gustavo Daher (gdaherufc@hotmail.com) on 2017-01-06T16:26:55Z No. of bitstreams: 1 2016_dis_avbezerrajunior.pdf: 1765886 bytes, checksum: 6d7d4cc59cc428f0bd730303a986bdea (MD5) / Approved for entry into archive by Márcia Araújo (marcia_m_bezerra@yahoo.com.br) on 2017-01-25T12:09:12Z (GMT) No. of bitstreams: 1 2016_dis_avbezerrajunior.pdf: 1765886 bytes, checksum: 6d7d4cc59cc428f0bd730303a986bdea (MD5) / Made available in DSpace on 2017-01-25T12:09:12Z (GMT). No. of bitstreams: 1 2016_dis_avbezerrajunior.pdf: 1765886 bytes, checksum: 6d7d4cc59cc428f0bd730303a986bdea (MD5) Previous issue date: 2016 / The approval in the OAB exam is a legal requirement to all law school bachelors that aim to be a lawyer. Since its adoption, it has undergone several critical about its legality, necessity and even effectiveness. Just like in other countries, the OAB, the guardian of the attorney’s profession, uses a measurement test to select only candidates who demonstrate the essential knowledge, skills and abilities to the practice of law. The effective higher education’s evaluation is a task performed by the MEC, through SINAES, in which ENADE is the component used to measure the student’s evaluation. Through Bloom’s educational objectives taxonomy, this research proposes to find the real nature of the OAB exam, in comparison to ENADE’s one, by mapping the educational objectives required in both tests in the years of 2012. Data obtained from the analysis of the instruments shows that the OAB exam worked in the category of knowledge, and the ENADE focused on the next one, the comprehension. / A aprovação no Exame da OAB é exigência legalmente imposta a todos os bacharéis em direito que almejem exercer a advocacia. Desde a sua imposição, ela foi alvo de diversas críticas acerca da sua legalidade, necessidade e, até mesmo, eficácia. Enquanto guardiã da profissão de advogado, a OAB, como já ocorre em outros países, utiliza uma prova como mecanismo para selecionar apenas os candidatos que demonstram o conhecimento, capacidade e habilidades indispensáveis ao exercício da advocacia. Por outro lado, a efetiva avaliação do ensino superior, em toda a sua totalidade, é tarefa precipuamente executada pelo MEC através do SINAES, sendo o ENADE o componente utilizado para a avaliação dos estudantes. A presente pesquisa analisou as provas do Exame da OAB e do ENADE à luz da taxonomia dos objetivos educacionais de Benjamin Bloom, através do mapeamento dos objetivos educacionais exigidos nesses testes aplicados no ano de 2012. Os dados obtidos indicaram que os Exames da OAB trabalham no nível da categoria do conhecimento, ao passo que o ENADE explora mais a categoria imediatamente superior, a da compreensão.

Dans le secteur des soins de santé, les données d'images médicales toujours croissantes, le développement de technologies d'imagerie, la conservation à long terme des données médicales et l'augmentation de la résolution des images entraînent une croissance considérable du volume de données. En outre, la variété des dispositifs d'acquisition et la différence de préférences des médecins ou d'autres professionnels de la santé ont conduit à une grande variété de données. Bien que la norme DICOM (Digital Imaging et Communication in Medicine) soit aujourd'hui largement adoptée pour stocker et transférer les données médicales, les données DICOM ont toujours les caractéristiques 3V du Big Data: volume élevé, grande variété et grande vélocité. En outre, il existe une variété de charges de travail, notamment le traitement transactionnel en ligne (en anglais Online Transaction Processing, abrégé en OLTP), le traitement analytique en ligne (anglais Online Analytical Processing, abrégé en OLAP) et les charges de travail mixtes. Les systèmes existants ont des limites concernant ces caractéristiques des données et des charges de travail. Dans cette thèse, nous proposons de nouvelles méthodes efficaces pour stocker et interroger des données DICOM. Nous proposons un modèle de stockage hybride des magasins de lignes et de colonnes, appelé HYTORMO, ainsi que des stratégies de stockage de données et de traitement des requêtes. Tout d'abord, HYTORMO est conçu et mis en œuvre pour être déployé sur un environnement à grande échelle afin de permettre la gestion de grandes données médicales. Deuxièmement, la stratégie de stockage de données combine l'utilisation du partitionnement vertical et un stockage hybride pour créer des configurations de stockage de données qui peuvent réduire la demande d'espace de stockage et augmenter les performances de la charge de travail. Pour réaliser une telle configuration de stockage de données, l'une des deux approches de conception de stockage de données peut être appliquée: (1) conception basée sur des experts et (2) conception automatisée. Dans la première approche, les experts créent manuellement des configurations de stockage de données en regroupant les attributs des données DICOM et en sélectionnant une disposition de stockage de données appropriée pour chaque groupe de colonnes. Dans la dernière approche, nous proposons un cadre de conception automatisé hybride, appelé HADF. HADF dépend des mesures de similarité (entre attributs) qui prennent en compte les impacts des informations spécifiques à la charge de travail et aux données pour générer automatiquement les configurations de stockage de données: Hybrid Similarity (combinaison pondérée de similarité d'accès d'attribut et de similarité de densité d'attribut) les attributs dans les groupes de colonnes; Inter-Cluster Access Similarity est utilisé pour déterminer si deux groupes de colonnes seront fusionnés ou non (pour réduire le nombre de jointures supplémentaires); et Intra-Cluster Access La similarité est appliquée pour décider si un groupe de colonnes sera stocké dans une ligne ou un magasin de colonnes. Enfin, nous proposons une stratégie de traitement des requêtes adaptée et efficace construite sur HYTORMO. Il considère l'utilisation des jointures internes et des jointures externes gauche pour empêcher la perte de données si vous utilisez uniquement des jointures internes entre des tables partitionnées verticalement. De plus, une intersection de filtres Bloom (intersection of Bloom filters, abrégé en ) est appliqué pour supprimer les données non pertinentes des tables d'entrée des opérations de jointure; cela permet de réduire les coûts d'E / S réseau. (...) / In the health care industry, the ever-increasing medical image data, the development of imaging technologies, the long-term retention of medical data and the increase of image resolution are causing a tremendous growth in data volume. In addition, the variety of acquisition devices and the difference in preferences of physicians or other health-care professionals have led to a high variety in data. Although today DICOM (Digital Imaging and Communication in Medicine) standard has been widely adopted to store and transfer the medical data, DICOM data still has the 3Vs characteristics of Big Data: high volume, high variety and high velocity. Besides, there is a variety of workloads including Online Transaction Processing (OLTP), Online Analytical Processing (OLAP) and mixed workloads. Existing systems have limitations dealing with these characteristics of data and workloads. In this thesis, we propose new efficient methods for storing and querying DICOM data. We propose a hybrid storage model of row and column stores, called HYTORMO, together with data storage and query processing strategies. First, HYTORMO is designed and implemented to be deployed on large-scale environment to make it possible to manage big medical data. Second, the data storage strategy combines the use of vertical partitioning and a hybrid store to create data storage configurations that can reduce storage space demand and increase workload performance. To achieve such a data storage configuration, one of two data storage design approaches can be applied: (1) expert-based design and (2) automated design. In the former approach, experts manually create data storage configurations by grouping attributes and selecting a suitable data layout for each column group. In the latter approach, we propose a hybrid automated design framework, called HADF. HADF depends on similarity measures (between attributes) that can take into consideration the combined impact of both workload- and data-specific information to generate data storage configurations: Hybrid Similarity (a weighted combination of Attribute Access and Density Similarity measures) is used to group the attributes into column groups; Inter-Cluster Access Similarity is used to determine whether two column groups will be merged together or not (to reduce the number of joins); and Intra-Cluster Access Similarity is applied to decide whether a column group will be stored in a row or a column store. Finally, we propose a suitable and efficient query processing strategy built on top of HYTORMO. It considers the use of both inner joins and left-outer joins. Furthermore, an Intersection Bloom filter () is applied to reduce network I/O cost.We provide experimental evaluations to validate the benefits of the proposed methods over real DICOM datasets. Experimental results show that the mixed use of both row and column stores outperforms a pure row store and a pure column store. The combined impact of both workload-and data-specific information is helpful for HADF to be able to produce good data storage configurations. Moreover, the query processing strategy with the use of the can improve the execution time of an experimental query up to 50% when compared to the case where no is applied.

abstract: Sea ice algae dominated by diatoms inhabit the brine channels of the Arctic sea ice and serve as the base of the Arctic marine food web in the spring. I studied sea ice diatoms in the bottom 10 cm of first year land-fast sea ice off the coast of Barrow, AK, in spring of 2011, 2012, and 2013. I investigated the variability in the biomass and the community composition of these sea-ice diatoms between bloom phases, as a function of overlying snow depth and over time. The dominant genera were the pennate diatoms Nitzschia, Navicula, Thalassiothrix, and Fragilariopsis with only a minor contribution by centric diatoms. While diatom biomass as estimated by organic carbon changed significantly between early, peak, and declining bloom phases (average of 1.6 mg C L-1, 5.7 mg C L-1, and 1.0 mg C L-1, respectively), the relative ratio of the dominant diatom groups did not change. However, after export, when the diatoms melt out of the ice into the underlying water, diatom biomass dropped by ~73% and the diatom community shifted to one dominated by centric diatoms. I also found that diatom biomass was ~77% lower under high snow cover (>20 cm) compared to low snow cover (<8 cm); however, the ratio of the diatom categories relative to particulate organic carbon (POC) was again unchanged. The diatom biomass was significantly different between the three sampling years (average of 2.4 mg C L-1 in 2011, 1.1 mg C L-1 in 2012, and 5.4 mg C L-1 in 2013, respectively) as was the contribution of all of the dominant genera to POC. I hypothesize the latter to be due to differences in the history of ice sheet formation each year. The temporal variability of these algal communities will influence their availability for pelagic or benthic consumers. Furthermore, in an Arctic that is changing rapidly with earlier sea ice and snowmelt, this time series study will constitute an important baseline for further studies on how the changing Arctic influences the algal community immured in sea ice. / Dissertation/Thesis / Masters Thesis Biology 2014

This research entitled "Biochemistry at School: a didactic proposal for meaningful learning" is characterized by being predominantly qualitative, which used as strategy the elaboration and application of a didactic sequence constructed from learning objectives proposed according to the revised Bloom’s Taxonomy. This didactic sequence aimed at reinforcing different abilities of the cognitive domain classified in levels and categories and favoring the meaningful learning of Chemistry contents in the classroom for last year students of high school from a public school of Santa Maria - RS, as well as strengthening the pedagogical and didactic knowledge of teachers in initial formation of Chemistry Degree of the Federal University of Santa Maria. For this, the study was developed in three phases. In the first phase, the aim was to achieve the pedagogical theoretical reference on meaningful and disciplinary learning about the concepts to be approached, such as proteins, carbohydrates and lipids. The second phase was addressed to the theoretical and practical orientation of the teachers in initial formation for the construction of the didactic sequence, approaching different scientific contents in several interventions. The interventions were organized in three thematic workshops based on the Three Pedagogical Moments and the learning objectives proposed for the six levels and categories of knowledge organization of the revised Bloom’s Taxonomy. The third and final step was to apply in the classroom the didactic sequence constructed by the teachers in initial formation and evaluation of the constructed learning. The results of this study were obtained through different data collection instruments, such as: questionnaires, textual productions, didactic sequence activities and the observations and annotations of the researcher, which were analyzed according to the Textual Discourse Analysis. The active participation of teachers in initial formation in studies that provide spaces for articulating university-school, strengthening the pedagogical and didactic knowledge developed during their school and university life, since the teacher needs the use of those in the planning and application of activities, promoting improvements in the teaching process. Furthermore, the results allowed concluding that the application of the didactic sequence favored the meaningful learning of scientific concepts, inasmuch as an evolution was observed in the construction of the knowledge and skills of the cognitive domain of high school students. / Esta pesquisa intitulada “Bioquímica na Escola: uma proposta didática para a aprendizagem significativa” é caracterizada por ser predominantemente qualitativa, a qual utilizou como estratégia a elaboração e aplicação de uma sequência didática construída a partir de objetivos de aprendizagem propostos conforme à Taxonomia de Bloom revisada. Esta sequência didática teve como finalidade reforçar diferentes habilidades do domínio cognitivo classificadas em níveis e categorias e favorecer a aprendizagem significativa de conteúdos de Química em sala de aula para estudantes da 3ª série do Ensino Médio de uma escola estadual de Santa Maria – RS, bem como fortalecer os conhecimentos pedagógicos e didáticos de professores em formação inicial do curso de Química Licenciatura da Universidade Federal de Santa Maria. Para isso, a pesquisa foi desenvolvida em três fases. Na primeira fase, buscou-se o referencial teórico pedagógico sobre a aprendizagem significativa e disciplinar a respeito dos conceitos a serem abordados, tais como: proteínas, carboidratos e lipídeos. A segunda fase foi direcionada para a orientação teórica e prática dos professores em formação inicial para a construção da sequência didática, abordando diferentes conteúdos científicos em várias intervenções. As intervenções foram organizadas em três oficinas temáticas estruturadas nos Três Momentos Pedagógicas e nos objetivos de aprendizagem propostos para os seis níveis e categorias de organização do conhecimento da Taxonomia de Bloom revisada. A terceira e última etapa, destinou-se à aplicação em sala de aula da sequência didática construída pelos professores em formação inicial e avaliação da aprendizagem construída. Os resultados desta pesquisa foram obtidos por meio de diferentes instrumentos de coleta de dados, tais como: questionários, produções textuais, atividades da sequência didática e as observações e anotações do pesquisador, os quais foram analisados segundo a Análise Textual Discursiva. Conclui-se que a participação ativa dos professores em formação inicial em pesquisas que propiciem espaços para articular universidade-escola, fortalece os conhecimentos pedagógicos e didáticos desenvolvidos durante sua vida escolar e universitária, visto que precisa do uso deste no planejamento e aplicação de atividades, promovendo melhorias no processo de ensino. Além disso, os resultados permitiram concluir que a aplicação da sequência didática favoreceu a aprendizagem significativa de conceitos científicos, pois foi observado uma evolução na construção do conhecimentos e habilidades do domínio cognitivo dos estudantes do ensino médio.

O trabalho teve por objetivo avaliar a qualidade de água em viveiro de piscicultura com florescimento de cianobactérias e a toxicidade aguda (DL50-24h) de microcistina nas espécies matrinxã (Brycon cephalus) e tilápia nilótica (Oreochromis niloticus), bem como as alterações histológicas nas brânquias, rins e fígado nos peixes. Foi realizado o monitoramento da qualidade de água de um empreendimento piscícola localizado na cidade de Espírito Santo do Pinhal/SP, Brasil. Foram realizadas, em datas distintas, duas coletas de amostras de água contendo floração de microalgas, para análise da composição fitoplanctônica, determinação de toxinas e bioensaios toxicológicos em laboratório. Foram realizadas medições das variáveis físicas, químicas e biológicas da água, e determinação do estado trófico do viveiro monitorado. O viveiro apresentava-se hipereutrófico, com presença de cianotoxinas representadas por microcistinas com valores variando entre 229,2 e 147,4 µg/g. O florescimento de cianobactérias apresentou-se de composição mista, representado principalmente pelas espécies Anabaena circinalis, A. spiroides, Aphanocapsa sp., Microcystis aeruginosa, M. panniformis, M. viridis, M. cf. wesembergii, Pseudanabaena mucicola, entre outras espécies. Os resultados dos bioensaios com microcistina obtida do extrato bruto de fitoplâncton do florescimento não apresentaram letalidade para os peixes. Contudo, foram verificadas alterações em órgãos dos peixes testados, como a presença de depósitos hepatocelulares intracitoplasmáticos, degeneração vacuolar observada em epitélio tubular renal, e proliferação de epitélio de revestimento (hiperplasia) das brânquias, com casos de fusão total das lamelas secundárias, tanto para matrinxã como para tilápia nilótica. Extratos brutos de cianotoxina, em concentrações a partir de 125 mg/kg de peso corporal, injetados em peixes provocam efeitos deletérios com expressiva alteração nas brânquias, rins e fígado. / The aim of this study was to evaluate the water quality in fish earthpond with blooms of cyanobacterias and acute toxicity (DL50 - 24 hs) of microcystin in species (Brycon cephalus) and tilapia nilotica (Oreochromis niloticus) as well as histological changes in gills, kidney and liver in fish. Water quality monitoring was carryed out in a pisciculture in Espirito Santo do Pinhal city, SP, Brazil. There were two collections of water samples containing bloom of cyanobacteria for analysis of microalgae composition, toxin determination and toxicological bioassay in laboratory. Measurements of physical, chemical and biological variables were done and determination of trophic status of pond water were monitored. The results according to the trophic state index of samples taken showed hipereutrophic state for the pond water. Was evident the presence of cyanobacteria, represented by microcystins with values ranging from 229.2 to 147.4 µg/g. The bloom of cyanobacteria presented mixed composition, represented mainly by species Anabaena circinalis, Anabaena spiroides, Aphanocapsa sp., Microcystis aeruginosa, Microcystis panniformis, Microcystis viridis, Microcystis cf. Wesembergii, Pseudanabaena mucicola among others. The results of tests with crude extract of bloom cyanobacteria did not show mortality of fish. However, there were changes in cellular structures of fish tested as the presence of hepatocellular intracytoplasmatic deposit, vacuolar degeneration observed in renal tubular epithelium, and proliferation of epithelial lining (hyperplasia) of gills, with cases of total fusion of secondary lamellae for both tilapias and for matrinxã. Crude extract of cyanotoxins, in concentrations of 125 mg/kg of body weight, injected in fishes provoke deleterious effect with expressive changes in the gills, kidney and liver.

O mapa conceitual é uma ferramenta gráfica de representação e organização do conhecimento. Seu objetivo é explicitar relações hierárquicas e significativas entre conceitos na forma de proposições. Este trabalho buscou investigar se o ensino de uma disciplina num curso de nível superior, no qual os alunos fossem solicitados a elaborar mapas conceituais, pode se mostrar capaz de levar estudantes universitários a níveis mais elevados de desempenho cognitivo. Os níveis cognitivos são compreendidos à luz da Taxionomia de Bloom, que visa classificar a ação mental esperada do estudante, a saber: lembrar, entender, aplicar, analisar, avaliar e criar. A pesquisa foi realizada durante um ano letivo em uma instituição de ensino superior, particular, do interior paulista com 48 estudantes do curso de Pedagogia. Os dados foram coletados por meio de avaliações escritas aplicadas ao final do primeiro semestre, quando não houve uso do mapa conceitual. E ao fim do segundo, após treinamento e uso do mapa conceitual. O resultado da análise estatística indica que, apenas na categoria lembrar, a diferença encontrada não foi estatisticamente significante entre as duas avaliações, indicando que a utilização do mapa conceitual como recurso de ensino não levou a um desempenho melhor por parte de quem o utilizou. Em todos os demais níveis as diferenças se mostraram altamente significantes, afirmando uma melhoria de desempenho por parte dos sujeitos quando utilizaram o recurso de elaborar individual e coletivamente o mapa conceitual, possibilitando inferir que o uso do mapa conceitual pode favorecer um melhor desempenho cognitivo em problemas que exijam níveis cognitivos mais complexos / The conceptual map is a graphical tool that shows the representation of ones knowledge and the organization of this knowledge. Its purpose is to make explicit hierarchical and meaningful connections among concepts in the form of propositions. This work sought to investigate if the teaching of a subject in a higher education major, in which students were asked to elaborate conceptual maps, is able to lead university students to higher levels of cognitive performance. The cognitive levels are understood in the light of Bloom\'s taxonomy, which aims to classify the expected mental action of the student, namely: to remember, to understand, to apply, to analyze, to evaluate and to create. The research was carried out during a school year in a private higher education institution, in the interior of São Paulo, with the participation of 48 students from the Pedagogy major. The data were collected through written assessments applied at the end of the first semester when there was no use of the conceptual map and also at the end of the second semester after practicing and using the conceptual map. The results of the statistical analysis indicate that the difference found in the remembering category alone was not statistically significant between the two assessments, indicating that the use of the conceptual map as a teaching resource did not lead to a better performance by those who used it. In all other levels, the differences were highly significant, affirming improvement in the performance of the subjects after having used the conceptual mapping feature, individually and collectively, enabling infer that the use of the conceptual map may favor a better cognitive performance in problems that require more complex cognitive levels

During the summer of 2013 the environmental office at Lycksele Municipality received a complaint, regarding algal blooms at the stream outlet between the lakes Kalven and Byssträsket in the southern parts of Lycksele Municipality. No deeper studies were made to ensure what could have caused the bloom. The purpose of this report was to examine if there was a specific source contributing to high levels of nutrients in the stream, mainly focusing on clear-cuts and a small dam by the stream inlet, and if the nutrient status differed along the stream flow. Therefore, suitable sites were picked for examination, following the stream flow between the two lakes, and in a stream not affected by clear-cuts for reference. Water samples were picked at each site, determining the status of the parameters total-nitrogen, total-phosphorus, nitrate, ammonium, pH and conductivity. The result showed quite high levels of total-phosphorus (ranging from 40-50 µg/l) and total-nitrogen (ranging from 350-450 µg/l), but low levels of ammonium and nitrate. The results showed no sign of a nutrient input from a specific location. The conclusion of this study is that the present nutrient levels could be high enough to result in a bloom, though probably dependent on contributing factors, such as warmer weather and lower water levels. An alternative explanation is that the nutrient levels could have been higher 2013, deriving from new clear-cuts, but that these clear-cuts stopped leaching nutrients due to older age. Hence, due to lack of previous studies no exact assumption can be made

La production primaire (PP) dans l'Océan Austral joue un rôle crucial dans la capacité des océans à absorber le carbon atmosphérique. Elle est caractérisée par une forte limitation en Fer et par un cycle saisonnier très marqué, présentant un bloom planctonique en fin d'hiver, plus ou moins intense selon les régions. Ma thèse est centrée sur la compréhension des mécanismes qui contrôlent ce bloom et sa variabilité, ainsi que sur les éléments, présents et futurs, qui contrôlent son intensité. J'ai abordé le premier aspect (phénologie et mécanismes) en mettant en place une approche mécaniste basée sur une nouvelle configuration du modèle biogéochimique PISCES forcé par un environnement physique 1D idéalisé. Cette méthodologie m'a permis de réconcilier les différentes théories sur la formation des blooms aux hautes-latitudes, d'identifier les spécificités du bloom de l'Océan Austral et de proposer des critères adaptés à sa détection dans les observations. En outre, les résultats de cette étude de modélisation ont été confrontés à ceux issues d'une deuxième approche, basée sur des observations satellitaires, ce qui a permis la localisation géographique des différentes phénologies de bloom que j'ai identifiées dans l'Océan Austral. Pour répondre au deuxième aspect (altération et changements futurs), j'ai également suivi une double approche. J'ai d'abord examiné comment les limitations par la lumière et par le fer se combinent, via la variabilité du cycle saisonnier du mélange vertical, et pilotent ainsi la production primaire dans l'Océan Austral actuel à l'aide de la configuration idéalisée présentée plus haut. Dans un deuxième temps, cette analyse a permis d'aider à l’interprétation des variations de PP observées dans les projections climatiques issues de 8 modèles couplés (CMIP5). L'ensemble de mes résultats permet de mieux comprendre les processus physiques et biologiques qui contrôlent la croissance du phytoplancton dans l'Océan Austral et d'appréhender comment la modification de ces processus peut entraîner des altérations de la PP dans une région clé pour l'évolution future du climat. / Primary production (PP) in the Southern Ocean (SO) plays a crucial role on atmospheric carbon uptake. PP in this ocean is highly iron-limited and presents a marked seasonal cycle. Such a seasonal cycle has a strong productive phase in late winter, called bloom, which distribution and intensity is highly variable. My PhD focus on two specific aspects of the PP in the SO: first, the mechanisms that drive such a bloom and its dynamics and, second, the elements able to control the bloom intensity at present and in the future. The first aspect (bloom phenology and mechanisms) was addressed by setting up a mechanistic approach based on a novel model configuration: a complex biogeochemical model (PISCES) forced by a 1D idealised physical framework. This methodology allowed me to conciliate the different bloom formation theories and to identify the SO bloom specificities. Moreover, I proposed how to use different bloom detection criteria to properly identify bloom from observations. Such criteria were then tested in a complementary observation-based approach (with satellite and in-situ data) to characterise different bloom phenologies and its spatial distribution in the SO. The second aspect (bloom intensity and future change) was also addressed by a twofold approach. First, using the 1D model, I studied how seasonal variability of vertical mixing combine light and Fe limitation to drive PP. Secondly, I used such an analysis to interpret PP trends observed in 8 coupled model climatic projections (CMIP5 models). My PhD thesis results allow for a better understanding of the physical and biological processes controlling phytoplankton growth. My conclusions also suggest how an alteration of these processes by Climate Change may influence PP in the whole SO, a key region for future climate evolution.