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Este proyecto plantea la construcción de un Centro Oceanográfico del Mar Menor que permita un estudio permanente de las condiciones de la laguna y que desarrolle funciones de asesoramiento científico a las administraciones públicas en temas relacionados con el estado y explotación del mar Menor, además de abordar diferentes estudios como: el oceanográfico integral de la laguna, el conocimiento científico y transversal sobre el funcionamiento hidrodinámico e hidrográfico, la naturaleza geológica y biológica de los fondos marinos, la explotación pesquera de sus recursos, el impacto que sobre la laguna puede significar la urbanización de su litoral y su utilización como recurso de ocio y un estudio sobre el impacto y transformaciones biológicas que suponer los nutrientes de origen agrícola. Las condiciones geográficas, ambientales y climáticas han propiciado que el Mar Menor tenga un ecosistema peculiar, diferente al del mar Mediterráneo, donde destacan cinco figuras de protección a nivel regional, europeo y mundial. Algunas de estas peculiaridades son: fondos limosos y arenosos, algas o fanerógamas marinas, nidificación de aves marinas, numerosas especies de peces, zonas salinas y vegetación autóctona. El mar Menor, debido a sus características de laguna cerrada, salvo sus golas, y a la fuerte amenaza de una serie de factores, que luego enumeraremos, ve gravemente amenazada la conservación de sus aguas y zonas litorales. Sus principales amenazas son: (1) PERCEPCIÓN: desconocimiento de los ecosistemas litorales y la percepción de estos espacios como zonas exclusivamente de veraneo o de ocio, sin valor ambiental alguno. Esto origina la utilización inadecuada de sus aguas y de su espacio litoral. (2) MEDITERRANEIZACIÓN: aumento de las comunicaciones entre el mar Menor y el mar Mediterráneo por el dragado y la ampliación de las golas. Esto origina que la laguna pierda sus características singulares y se parezca más al mar Mediterráneo. (3) CAMBIO CLIMÁTICO: está provocando la regresión de la costa por la subida de los niveles del mar, que a su vez provoca cambios en la salinidad, la diversidad de las especies y otros efectos. (4) REGRESIÓN DE LOS ARENALES: regresión y desaparición de los arenales por la disminución de sedimentos; la realización de obras litorales o la retirada sistemática de los arribazones de posidonia. (5) CAMBIOS EN EL USO DEL SUELO: un uso masivo del suelo para zonas de agricultura intensiva o urbanizaciones, que supone la desaparición de espacios naturales impidiendo la descontaminación natural de las aguas de escorrentía. (6) URBANIZACIÓN: las urbanizaciones, la inmensa mayoría de carácter turístico y de ocio, han ocupado gran parte del mar Menor e incluso se han construido como barreras que impiden el natural movimientos de los arenales y de las escorrentías de las lluvias. (7) CONTAMINACIÓN DE LAS AGUAS: debido a la llegada a la laguna de nutrientes de origen agrícolas que está provocando un proceso de entrofización del mar, que originariamente era pobre en nutrientes. Esto provoca, entre otros efectos, un aumento de algas verdes en superficie y una superpoblación de distintas especies de medusas, sobretodo en época estival. (8) ESPECIES INVASORAS: de plantas y animales que amenazan la población autóctona. (9) PESCA ILEGAL: provoca un riesgo para la fauna de aves marinas que mueren atrapadas en redes ilegales y esquilma la pesca de especies marinas; incluso no respetando las vedas reproductoras. En vista de todo lo anterior, queda justificada la construcción de un Centro Oceanográfico del Mar Menor que permita un estudio permanente de las condiciones de la laguna y que desarrolle funciones de asesoramiento científico a las administraciones públicas en temas relacionados con el estado y explotación del mar Menor, además de abordar diferentes estudios como: el oceanográfico integral de la laguna, el conocimiento científico y transversal sobre el funcionamiento hidrodinámico e hidrográfico, la naturaleza geológica y biológica de los fondos marinos, la explotación pesquera de sus recursos, el impacto que sobre la laguna puede significar la urbanización de su litoral y su utilización como recurso de ocio y un estudio sobre el impacto y transformaciones biológicas que suponer los nutrientes de origen agrícola. Escuela de Arquitectura e Ingeniería de Edificación Universidad Politécnica de Cartagena

This thesis shows that before 28 Ma a single water mass flowing westward, the proto-AABW, occupied the seafloor in the studied region. The first evidence for the onset of a current flowing eastward, the proto-CDW, is found at 28 Ma. Between 26 and 25 Ma ice sheets were mainly continental-based and an oceanic frontal system already existed and migrated during glacial-interglacial cycles that were paced by obliquity. The late Oligocene frontal system was however weaker than today´s Polar Front because we find evidence for intrusion of warm north component waters close to the Antarctic margin. The latest Oligocene (24-23.4 Ma) witnessed at least eight times of ice sheet advancing into the continental shelf and retreats inland, pointing to a highly dynamic ice sheet during the cooling trend leading to the glacial Mi-1 event. During this period, we interpret that the EAIS in the WSB becomes marine-based as a consequence of the erosion and overdeepening of the Wilkes Subglacial Basin by the repeated advances and retreats of the EAIS since it was formed in the early Oligocene (33.6 Ma)., Los resultados derivados de esta tesis muestran que antes de los 28 Ma una masa de agua, la AABW, circulaba hacia el oeste y ocupaba todo el fondo marino en la región estudiada. La primera evidencia de una corriente de agua hacia el este, la proto-CDW, es al comienzo del Oligoceno superior. Entre 26 y 25 Ma, los casquetes de hielo fundamentalmente eran continentales, y los sistemas oceánicos frontales ya existían y migraban durante los ciclos glaciares-interglaciares forzados por la oblicuidad. Sin embargo, la intrusión de aguas cálidas de componente norte cerca del margen Antártico muestra que dichos frentes eran más débiles que el Frente Polar actual. A finales del Oligoceno (24-23.4 Ma) el registro muestra al menos ocho avances de la EAIS a la plataforma continental y retrocesos hacia tierra, evidenciando un casquete de hielo muy dinámico durante la fase de enfriamiento que culmina en el evento glaciar Mi-1. Es en este periodo interpretamos que la EAIS pasa de estar anclado en tierra a estar anclado por debajo del nivel del mar (marine-based) como consecuencia de la erosión y la profundización de la Cuenca Subgacial de Wilkes durante avances repetidos de la EAIS desde su formación hace 33.6 Ma, Tesis Univ. Granada., Spanish Ministerio de Economía y Competitividad with the grants CTM 2011-24079 and CTM2014-60451-C2-1-P.

El objetivo de este artículo es la presentación del Sistema PORT 21 de previsión de oleaje y Oceanografía Operacional (OO) de aplicación en la Región Sudamericana. Para la comprensión integral del sistema se citan los modelos usados y se muestra en primer lugar la metodología adoptada para su integración en la implementación de PORT 21. Posteriormente se describen los casos estudiados para ilustrar el funcionamiento del sistema, incluyendo un caso de validación y calibración del sistema en el sur de Chile, para finalmente resumir los resultados hasta ahora obtenidos. Se presenta una revisión de las dependencias de datos de entrada que tiene el sistema describiéndose los diferentes modelos y fuentes de datos de viento y de oleaje existentes en el estado del arte, alguno de los cuales han sido seleccionados para el uso rutinario del sistema. En las conclusiones sobre los resultados obtenidos, se realiza un análisis crítico respecto de los objetivos alcanzados hasta la fecha y se describen las tareas a realizar en el futuro. Se señala que este trabajo ha sido parcialmente apoyado por la infraestructura de supercomputación del NLHPC (ECM-02), liderado por el Centro de Modelamiento Matemático (CMM) de la Universidad de Chile.

Bathymetry (seafloor depth), is a critical parameter providing the geospatial context for a multitude of marine scientific studies. Since 1997, the International Bathymetric Chart of the Arctic Ocean (IBCAO) has been the authoritative source of bathymetry for the Arctic Ocean. IBCAO has merged its efforts with the Nippon Foundation-GEBCO-Seabed 2030 Project, with the goal of mapping all of the oceans by 2030. Here we present the latest version (IBCAO Ver. 4.0), with more than twice the resolution (200 × 200 m versus 500 × 500 m) and with individual depth soundings constraining three times more area of the Arctic Ocean (∼19.8% versus 6.7%), than the previous IBCAO Ver. 3.0 released in 2012. Modern multibeam bathymetry comprises ∼14.3% in Ver. 4.0 compared to ∼5.4% in Ver. 3.0. Thus, the new IBCAO Ver. 4.0 has substantially more seafloor morphological information that offers new insights into a range of submarine features and processes; for example, the improved portrayal of Greenland fjords better serves predictive modelling of the fate of the Greenland Ice Sheet., Measurement(s)depthTechnology Type(s)digital curationFactor Type(s)geographic locationSample Characteristic - Environmentocean floorSample Characteristic - LocationArctic Ocean Machine-accessible metadata file describing the reported data: 10.6084/m9.figshare.12369314

The early Paleogene sedimentary record of the Sao Paulo Plateau holds the key to understanding the timing and mechanisms of the onset of Atlantic oceanic circulation, with implications for ocean – climate feedback systems. The timing and evolution of South Atlantic Ocean connectivity remain poorly understood, hindering a full understanding of modern circulation mechanisms. In this work, we develop an improved magnetostratigraphic age model for the late- Cretaceous to Eocene sedimentary record of Deep-Sea Drilling Project (DSDP) Site 356, located on the São Paulo Plateau at the edge of the Rio Grande Rise. The model constrains the timing of the beginning of Atlantic Ocean circulation, as the last obstacle to a connected Atlantic was removed. We use the age model to quantify sedimentary rates, and correlate with rock magnetic and published geochemical data to explore links between ocean current rearrangement and climatic anomalies. We find that periods characterized by variations in the magnetic properties of sediments and sedimentation anomalies in the Sao Paulo Plateau are reflected in carbon isotope events, supporting a possible link between ocean circulation and hyperthermal events.

Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Filosofia e Ciências Humanas, Programa de Pós-Graduação em Geografia, Florianópolis, 2020. A ilha de Santa Catarina, localizada no setor Sudeste da zona costeira brasileira, possui características geomorfológicas marcadas pelo contraste entre terras altas e planícies, cujas feições deposicionais costeiras holocênicas nela presentes se constituem no objeto de estudo da presente pesquisa. Visando o entendimento da evolução costeira holocênica, procurou-se analisar em detalhe os depósitos sedimentares com base no mapeamento geológico superficial e na abordagem sistêmica aplicada à geomorfologia costeira, afim de se identificar os ambientes de sedimentação e os sistemas deposicionais ocorrentes, bem como, de que forma se desenvolveram e se correlacionam com os modelos evolutivos conhecidos para o setor Central da costa catarinense. O desenvolvimento sobre condições de estabilidade relativa do nível médio do mar ao longo do Holoceno superior consiste na hipótese principal de pesquisa, onde o comportamento evolutivo destes sistemas costeiros associaram-se aos padrões internos das células litorâneas, variações no balanço sedimentar e, principalmente, aos processos autogênicos associados com a retroalimentação da morfodinâmica costeira em virtude do preenchimento dos espaços de acomodação de sedimentos. Nestes termos, os resultados obtidos com o mapeamento geológico superficial apontaram a ocorrência de quinze unidades deposicionais distintas: depósitos transicionais ? marinho praial, de baía, lagunar, lagunar praial, lacustre praial, eólico, fluviomarinho, fluviolagunar, fluviolacustre, fluviopaludial, paludial, estuarino e praiais atuais; depósitos antropogênicos ? prototecnogênico e tecnogênico. De acordo com as fácies ambientais reconhecidas (30 ao todo), estes depósitos foram agrupados em oito ambientes de sedimentação: ambientes transicionais ? litorâneo infrapraial, marinho praial, estuarino, eólico, pantanoso, lagunar e lacustre; ambientes antrópicos. Após a definição das unidades deposicionais e ambientes de sedimentação, passou-se ao ordenamento dos mesmos através da aplicação do conceito de sistemas deposicionais, empregando a Teoria Geral dos Sistemas em Geociências, o que resultou em quatro sistemas deposicionais: marinho raso (subsistemas de barreiras costeiras, terraços costeiros e praiais atuais), pantanoso-estuarino, aquoso lêntico (subsistemas lacustre e lagunar) e antropogênico. À estas avaliações, somaramse os dados de datações geocronológicas disponíveis, além da abordagem com base no enfoque aloestratigráfico, que possibilitaram a apresentação de um modelo evolutivo baseado em nove estádios paleogeográficos: etapa inicial marcada pela fase transgressiva durante o Holoceno médio, com posterior fase de estabilização (Estádios 0 e 1, anterior a 5,8 ka AP); seguindo a uma etapa regressiva composta por fase de queda (Estádio 2a, entre 5,8 e 3,3 ka AP) e de estabilização do nível médio do mar (Estádio 2b, por volta de 3,3 ka AP); passando a uma etapa de estabilidade relativa do nível médio do mar (Estádio 3a e 3b, entre 3,3 e 2,1 ka AP); seguindo-se por nova fase regressiva (Estádios 4a e 4b, entre 2,1 e 0,2 ka AP); culminando com nova etapa caracterizada por ações antropogênicas e início de uma aparente nova fase transgressiva (Estádio 5, situação atual). Estes resultados encontram-se alinhados com o observado nas demais áreas de planície no setor Central da costa catarinense e confirmam as hipóteses de pesquisa. Abstract: The Santa Catarina island, located at the southeast coast of Brazil, is marked by geomorphological contrast between highlands and plains, whose coastal Holocene depositional features are the object of study in this research. The sedimentary units were detailed, based on geological mapping and systemic analysis, to identify the sedimentary environments, depositional systems and to understand the holocenic coastal evolution model, as well as, their interrelation with the evolutionary models known for the central sector of the coast of Santa Catarina State. The hypothesis proposed is that coastal evolution occurred over a relative stillstand of the mean sea level along the upper Holocene. Therefore, the evolutionary behavior of coastal systems is associated with internal morphodynamics patterns, variations in the sediment budget and especially to the autogenic processes of the coastal morphodynamics feedback loop due to the filling of the spaces available for deposition. Fifteen deposits were mapped: transitional deposits ? beach marine, bay, lagoonal, beach lagoonal, beach lacustrine, eolic, fluviomarine, fluviolagoonal, fluviolacustrine, fluviopaludal, paludal, estuarine and beach; anthropogenic deposits ? proto-tecnogenic and tecnogenic. Thirty environmental facies were recognized and grouped in eight sedimentary environments: nearshore, beach marine, estuarine, eolic, paludal, lagoonal, lacustrine and anthropic. After defined deposits and sedimentary environments, they were ordered by the depositional systems concept using the General Theory of Systems applied to Geosciences, resulting in four depositional systems: shallow marine (coastal barrier, coastal terraces and beach subsystems), paludal-estuarine, lentic (lacustrine and lagoonal subsystems) and anthropogenic. In addition to the available radiometric dating and the allostratigraphic approach, which enabled the presentation of an evolutionary model based on nine paleogeographic stages: an initial stage marked by the marine transgression along the middle Holocene, with a subsequent stillstand phase (Stages 0 and 1, before 5.8 ky BP); a marine regression stage (Stage 2a, between 5.8 and 3.3 ky BP) following by a stabilization of the mean sea level (Stage 2b, around 3.3 ky BP); a relative stillstand of the mean sea level along the upper Holocene (Stages 3a and 3b, between 3.3 and 2.1 ky BP); a new marine regression phase (Stages 4a and 4b, between 2.1 and 0.2 ky BP); finally, an apparent new marine transgression phase characterized by human activity (Stage 5, current situation). These results correspond to those observed in others coastal plains in the central sector of the coast of Santa Catarina State and confirm the research hypothesis.

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Físicas e Matemáticas, Programa de Pós-Graduação em Oceanografia, Florianópolis, 2020. Ecossistemas costeiros têm sido pressionados por ameaças antrópicas e naturais. A pluralidade de atividades e usos humanos na planície costeira sujeita a eventos climáticos extremos cria um espaço potencialmente conflituoso, onde se faz necessária a atuação do poder público. Na medida em que os Serviços Ecossistêmicos se configuram como um indicador do estado de qualidade ambiental, torna-se fundamental considerá-los nas tomadas de decisão que envolvam atividades e usos humanos em ecossistemas. A Matriz de Serviços Ecossistêmicos da Ilha de Santa Catarina foi adaptada elencando todos os serviços e benefícios oferecidos pelos ecossistemas da orla marítima da Ilha. Além disso, a análise de risco aos ecossistemas e seus serviços, reconhecida internacionalmente como instrumento de suporte às tomadas de decisão, foi modelada através do software InVEST, com seu modelo de avaliação de risco ao hábitat. Considerando os eventos extremos recorrentes na Ilha nos últimos anos, os dados de risco foram associados a dados de susceptibilidade à erosão costeira obtidos do estado da arte, entendendo que áreas com maior risco e sujeitas à ocorrência de erosão demonstram uma maior necessidade de intervenção por parte da administração pública. Desta forma, uma média entre risco e susceptibilidade gerou hotspots de áreas prioritárias para gestão. A modelagem indica uma maior quantidade de ecossistemas praiais sob risco muito alto na porção norte da ilha, afetando 19 serviços. Para a floresta ombrófila, os valores altos correspondem ao norte (setor 3), leste (setor 5) e ao sul (setor 6), ameaçando 32 serviços. Dunas apresentam risco muito alto ao norte, ameaçando 18 serviços. O banhado, ecossistema com menos cobertura de solo na área de estudo, possui uma parcela sob risco muito alto no setor 5. Na restinga, o risco muito alto é indicado especialmente no norte, leste e sul (setores 3, 4, 5 e 6), afetando 30 serviços. Os resultados do risco gerados pelo modelo, em associação com a susceptibilidade à ocorrência de eventos erosivos apontaram 14 pontos classificados com risco muito alto, distribuídos ao longo de 7 praias, especialmente no norte da Ilha (setor 3). Recomenda-se o uso dos instrumentos de suporte à gestão disponíveis, especialmente o Plano de Gestão Integrada da Orla, para o estabelecimento de setbacks nas áreas ameaçadas, resguardando os ecossistemas, destacando os serviços ecossistêmicos relacionados à proteção costeira contra eventos extremos. Abstract: Seashore are the most pressured areas by the presence of activities and by occupation without planning. Conversely, this activities are important for social and economic development and the maintenance of it depends essentially on the Ecosystems and their services. Santa Catarina Island is located in Brazil and have a extensive infrastructure in order to meet the demands of sun and beach tourism. At the same time, coastal erosion events have been increasing. Ecosystem services risk analysis is recognized as an instrument to support decision-making. Ranking priority areas for management according to the risk of ecosystems and the susceptibility of the occurrence of erosion processes favoring most assertive public policies. The classification of Ecosystem Services was made with CICES V.05. Risk analyses was modeled by software InVEST, with Habitat Risk Assessment, considering two major threats: tourism and urbanization. It was related to geoindicators points who indicates erosion susceptibility. A greater number of beach at very high risk in the northern portion of the island, affecting 19 services. For the rainforest, the high values correspond to the north, east and south, threatening 32 services. Dunes present a very high risk in the north, threatening 18 services. The wetlands has a very high risk portion in east. In the restinga, the very high risk is indicated especially in the north, east and south affecting 30 services. The results pointed out 14 classified priority management areas distributed along 7 beaches, especially in the north of the Island. The use of available management support instruments is recommended, especially the Shoreline Management Plans, for the establishment of setbacks in threatened areas, protecting ecosystems and their services, in particular to those related to coastal protection against extreme events.

Muestra los principales resultados de las investigaciones en el mar y las aguas continentales nacionales obtenidos durante el año 2019.

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Físicas e Matemáticas, Programa de Pós-Graduação em Oceanografia, Florianópolis, 2020. Processos sedimentares conduzidos por correntes de gravidade talude abaixo e correntes de contorno paralelas ao talude são fenômenos comuns ao longo das margens continentais e podem ser distinguidos por sua energia, competência e duração de fluxo. No entanto, sua distinção no registro geológico, tanto em depósitos sedimentares quanto em dados sísmicos, requer análises complexas e detalhadas. Um cenário favorável a interação e alternância entre esses processos deposicionais pode fornecer uma compreensão mais aprofundada dos reservatórios marinhos profundos e sua formação sob as mudanças oceanográficas e morfológicas do fundo. Este trabalho busca compreender os processos deposicionais que operam nas margens continentais do sul do Brasil, onde o sistema era dominado por correntes de contorno e posteriormente por correntes de turbidez, formando um sistema submarino de cânion-canal que foi continuamente retrabalhado em seu talude superior/médio, evidenciado por ondas de sedimentos e driftes contorníticos. Um novo modelo evolutivo é proposto para o sistema Itabapoana (Bacia de Campos, Brasil), um sistema turbidito-contornito tectônicamente controlado, ativo do Neógeno ao Holoceno; bem como a configuração do fluxo que atuou durante o sistema de turbidez ativo. A partir dos dados sísmicos 2D, juntamente com atributos sísmicos, cinco sequências deposicionais são reconhecidas para a área de estudo da porção norte da Bacia de Campos, que abrange não somente o sistema Itabapoana, mas também o sistema Marataízes. Os resultados encontrados apontam que os processos sedimentares dominados por correntes de contorno ocorreram durante períodos de mar alto, promovendo depósitos de grãos finos como plastered drifts. Enquanto, em períodos de nível de mar baixo, correntes de turbidez erosivas e arenosas formavam canais submarinos que posteriormente foram retrabalhados por correntes de fundo. Assim, os resultados destacam os padrões de deposição cíclica dominados pelas correntes de contorno e turbidez na margem continental estudada. Dessa forma, como canais submarinos são consequência da ação dominante da corrente de turbidez sobre o fundo do mar em evolução, um fluxo formativo foi reconstruído usando a geometria hidráulica do sistema de canais Itabapoana. Os valores médios calculados de velocidade e descarga do fluxo são 1,05 m/s e 4,12 x 104 m³/s, respectivamente. Essa descoberta confere ao sistema uma feição de gradação vertical corroborado pelos refletores de alta amplitude (HARs) sobre o talude médio. Abstract: Sedimentary processes driven by downslope gravity currents and alongslope contour currents are common phenomena along continental margins and may be distinguished by their flow energy, competency and duration. However, their distinction in the geological record, either in sedimentary deposits or in seismic data, requires complex and detailed analyses. A privileged scenario for interaction and alternation among downslope and alongslope can provide further understanding of deep-marine reservoirs and their formation under oceanographic changes and bedform morphologies. This work attends to understand the depositional processes operating along the southern Brazilian continental margins, where the system was dominated by contour currents and later by turbidity currents, forming a canyon-channel submarine system that was continuously reworked on its upper/middle slope section, evidenced by sediment waves and contour drifts. Here, is presented an evolutive model for the Itabapoana system (Campos Basin, Brazil), a structurally-controlled mixed turbidite-contourite system active from the Neogene to the Quaternary, along with the formative flow that occurred during the active turbidite system in the northern Campos Basin. Using 2D seismic database along with seismic attributes, five depositional sequences are recognized for the study area which covers not only the Itabapoana System but also the Marataízes System, both on the northern Campos Basin. Sedimentary processes dominated by contour currents occurred during highstands, promoting fine-grain deposits as contourite plastered drifts. Whereas, at lowstands, erosive turbidity currents and resulting sand deposits formed submarine channels that were eventually reworked by downward bottom currents on the upper/middle slope section of the channel. Thus, our results highlight the cyclic deposition patterns dominated by contour and turbidity currents in the studied continental slope. As deep-water channels analyzed in this study are a consequence of the dominant turbidity current action over the evolving seafloor, a formative flow was reconstructed using the hydraulic geometry of the Itabapoana?s submarine channel system. The calculated mean values of flow velocity and discharge are 1.05m.s-1 and 4.12 x 104m³.s-1, respectively. These findings confer the system a vertical aggrading feature seen in high amplitude reflectors (HARs) over the middle slope.

In this study, we combine the use of Metal/Metal ratios of 134 sediment samples with multivariate analysis to provide the first geochemical mapping of a large subtropical estuary influenced by one of the largest grain-shipping terminals of South America. Together with grain-size data, the results allowed us to efficiently map the different sectors of the estuarine complex, defining its geochemical faciology. Also, potassium-related ratios appeared to be reliable proxies for the identification of point sources of terrigenous sediments. Since there was no evidence of widespread trace metal contamination, the results here presented can be used as a baseline for the area.

En este trabajo se obtuvieron hidrolizados proteicos de anchoíta Engraulis anchoita; utilizando enzimas recuperadas de desechos (cabezas y vísceras) de las siguientes especies pesqueras: el langostino Pleoticus muelleri, la merluza Merluccius hubbsi y la anchoíta E. anchoita. Para esto, se utilizaron las enzimas recuperadas al 1% (p/v) y se comparó su acción así como la calidad de los hidrolizados proteicos obtenidos, con dos elaborados con enzimas comerciales Alcalase 2.4 L-FG® y Neutrase 0.8L®. Con respecto al grado de hidrólisis alcanzado por los hidrolizados proteicos, los elaborados con enzimas recuperadas de la industria pesquera resultaron igualar y superar a los conseguidos con enzimas comerciales. También se analizó la capacidad de cada hidrolizado proteico de barrer el radical libre DPPH (EB), resultando todos los hidrolizados efectivos con valores que llegan al 80% de EB. Estos resultados se relacionan con la cantidad de ácidos grasos n-3 y n-6 encontrados en los mismos, los cuales ayudarían a incrementar el efecto barredor de radicales libre. Asimismo, la concentración proteica de todos los hidrolizados (80%), el bajo contenido de ácidos grasos trans y los contenidos de Nitrógeno Básico Volátil hacen que los mismos puedan ser aptos para el consumo humano y animal. En conclusión, la aplicación de los resultados de este estudio podrá beneficiar al sector pesquero argentino en cuanto a la valorización integral de las capturas y la utilización y puesta en valor de desechos provenientes del procesado de anchoita, langostino y merluza. Así la industria alimentaria tendrá a disposición nuevas enzimas y fuentes proteicas alternativas utilizables en diferentes procesos tecnológicos. Fil: Pereira, Nair de Los Angeles. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina Fil: Fangio, Maria Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Físicas de Mar del Plata. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Físicas de Mar del Plata; Argentina Fil: Rodriguez, Yamila Eliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina Fil: Garbari, Delfina María. Instituto Nacional de Tecnología Industrial; Argentina Fil: Fernandez Gimenez, Analia Veronica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina

Orientadora: Profª Regiane Dalazoana Dissertação (mestrado) - Universidade Federal do Paraná, Setor de Ciências da Terra, Programa de Pós-Graduação em Ciências Geodésicas. Defesa : Curitiba, 24/07/2020 Inclui referências: p. 99-108 Resumo: Os satélites altimétricos e os marégrafos permitem monitorar as variações do nível do mar ao longo do tempo. Enquanto os marégrafos observam o nível do mar relativo a um referencial local, os satélites altimétricos o fazem em relação ao geocentro da Terra. Da comparação entre as duas séries temporais de dados, observam-se diferenças que podem estar relacionadas a possíveis movimentos verticais da crosta (??U(?, ?)). Esses movimentos perturbam a componente vertical da posição dos marégrafos e, consequentemente, contaminam as observações do nível do mar. A instalação de uma estação de monitoramento contínuo GNSS nas proximidades dos marégrafos possibilita determinar a tendência de movimento vertical absoluto da crosta (TUp?GNSS). Objetivase no presente trabalho determinar o valor de possíveis movimentos verticais da crosta a partir da diferença entre a tendência do nível do mar observada pelos satélites altimétricos T/P, Jason 1, 2 e 3 (??A(?, ?)), entre 1992 e 2017, e a tendência do nível do mar observado pelo marégrafo de Imbituba-SC (??TG(?, ?)EMMIMB) entre 2002 e 2015. Para tanto, foram confeccionadas células ao longo das trilhas dos satélite a um raio de até 500 km sobre o oceano a partir da localização da estação maregráfica, abrangendo os passes 0239, 0228, 0152, 0076, 0163 e 0050. Para a análise de movimentos verticais da crosta, foram empregadas 15 células que obtiveram os melhores coeficientes de correlação (r) em relação aos dados maregráficos. Os resultados indicaram uma correlação moderada de 0,69 e as 15 células se localizaram ao longo do passe 0163 a uma distância média de 234,40 km da estação maregráfica. Os resultados obtidos indicaram uma tendência de subsidência da estação em Imbituba-SC. Destaca-se que não foi realizada a extrapolação dos dados altimétricos até a costa e nem a correção de erros de deriva instrumental contidos nas observações da maregráficas. Os valores médios de ??A(?, ?) (1992-2017), ??TG(?, ?)EMMIMB (2002-2015) foram de 2,53 } 1,18 e 5,42 } 1,88 mm/ano, respectivamente, enquanto que os valores médios de ??A(?, ?) (2007-2015), ??TG(?, ?)EMMIMB (2007-2015) foram de 7,10 } 4,62 e 12,97 } 4,23 mm/ano, respectivamente, podendo indicar uma aceleração do aumento do nível do mar em Imbituba-SC com o decorrer dos anos. Verifica-se também que o erro padrão da regressão foi menor quando foram empregadas séries temporais mais longas de dados da altimetria satelital e dados maregráficos. Palavras-chaves: Nível Médio do Mar. Movimento Vertical da Crosta. Altimetria por Satélite. Marégrafo de Imbituba-SC. Abstract: Altimetric satellites and tide gauges allow to monitor the sea level variations over the time. While tide gauges observe the sea level according to a local reference, the satellite altimetry do it according to the Earth Geocentric. From the comparison between the two-time series of data, differences that may be related to possible crustal vertical motion are observed (??U(?, ?)). These movements disturb the vertical component of the tide gauges position and contaminate the sea level observations consequently. The installation of a GNSS continuous monitoring station in the tide gauges vicinity makes it possible to determine the tendency of the absolute crustal vertical motion (TUp?GNSS). The objective of this work is to determine the value of possible crustal vertical motions from the difference between the sea level trend observed by satellites T/P, Jason 1, 2 and 3 (??A(?, ?)), between 1992 and 2017, and the sea level trend observed by the tide gauges of Imbituba-SC (??TG(?, ?)EMMIMB) between 2002 and 2015. To this end, cells were made along the satellite tracks at a radius of up to 500 km over the ocean from the tide gauges station location, covering 0239, 0228, 0152, 0076, 0163 and 0050 passes. For the crustal vertical motion analysis, 15 cells that obtained the best correlation coefficient (r) related to the tide gauges data were used. The results indicated an moderate correlation of 0,69 and the 15 cells were located along the 0163 pass at an mean distance of 234.40 km from the tide gauges station. The results indicated a subsidence trend in Imbituba-SC station. It is worthy to highlight that neither the altimetry dates extrapolation up to the coast was performed nor the correction of instrumental drift errors contained in the tide gauges observations. The mean values of ?? A(?, ?) (1992-2017), ??TG(?, ?)EMMIMB (2002-2015) were 2,53 } 1,18 and 5,42 } 1,88 mm/year, respectively, while the mean values of ?? A(?, ?) (2007-2015), ??TG(?, ?)EMMIMB (2007-2015) were 7,10 } 4,62 and 12,97 } 4,23 mm/year, respectively, which may indicate a sea level increase acceleration in Imbituba-SC over the years. It was also verified that the standard regression error was lower when longer time series of satellite altimetry and tide gauges data were used. Key-words: Mean Sea Level. Crustal Vertical Motion. Satellite Altimetry. Imbituba-SC Tide Gauges.

Vengono riportate le previsioni di marea riferite alla componente astronomica della variazione complessiva del livello marino per il Golfo di Trieste per l'anno 2020 e, più in particolare, le tabelle mensili delle alte e basse maree giornaliere con le fasi lunari, le tabelle mensili della marea astronomica calcolata per ogni giorno dell'anno dalle ore 1 alle 24 ed i grafici mensili della marea astronomica.

São Cristóvão, SE

Este estudio identifica posibles cambios en el Mar Caribe durante el siglo XXI utilizando tres modelos climáticos proporcionados por la Quinta Fase del Proyecto de Intercomparación de Modelos Acoplados (CMIP5) bajo el escenario HISTORICAL y utilizando dos escenarios de emisiones representativos (RCP4.5, RCP8.5). La evaluación incluye la temperatura de la superficial del aire, la presión atmosférica y el viento, así como la temperatura superficial del océano, salinidad superficial y los cambios del nivel medio del mar en 2050 y 2100 con respecto a 2005. Los resultados indican que independientemente del RCP utilizado, habrá aumentos considerables en temperatura del aire (1.5 a 4.0 C°) y de la superficie del mar (1.4 a 2.9 C°), lo que tiene el potencial de ampliar la temporada de huracanes y aumentar su frecuencia de ocurrencia en la región. Además, el aumento de la temperatura del océano probablemente incrementara el blanqueamiento de los corales en el Mar Caribe. Las tendencias medias del nivel del mar muestran un aumento notable en el período 2005-2100 (24.02 a 70.94 cm/siglo) en comparación con los períodos 1960-2005 (4.53 a 14.64 cm/siglo) y 1850-2005 (2.44 a 9.42 cm/siglo). Si bien las tendencias esperadas del nivel del mar en el Caribe están por debajo de la mediana de las proyecciones globales, debido al ambiente micromareal de la región, tales tendencias tienen el potencial de aumentar las inundaciones y la erosión, poniendo en riesgo islas de bajo nivel como algunas del Archipiélago de San Andrés y Providencia. Maestría Magister en Física Aplicada

El propósito de esta investigación fue determinar efectos de los periodos oceanográficos en los volúmenes de desembarque de invertebrados marinos en el puerto Pacasmayo entre los años 2015 y 2017. Los datos de volúmenes de desembarque, temperatura y salinidad fueron obtenidos de la estación fija del IMARPE – Pacasmayo. Con las variables temperatura y salinidad superficial del mar se conocieron las condiciones oceanográficas, identificándose ocho periodos, B fue cálido y de mayor duración (12 meses); mientras que, E fue transición de menor duración (1 mes). El análisis de clasificación jerárquica (cluster) con una similaridad de 75% y el Escalamiento Multidimensional (MDS) con stress 0,19 formaron seis grupos (volúmenes de desembarque) con los periodos oceanográficos, de los cuales, cinco fueron cálidos y transición; mientras que, un grupo fue neutro. Panulirus gracilis S. “langosta” y Xiphopenaeus riveti B. “camarón tití”, presentaron ampliación en su distribución espacial y temporal en torno a los periodos cálidos. Lo contrario a los periodos de transición y neutro fue con Platyxanthus orbignyi (ME & L) “cangrejo violáceo”, modificando directamente su accesibilidad y disponibilidad para la pesca artesanal. ABSTRACT: This research aimed to determine the effects of oceanographic periods on the landing volumes of marine invertebrates in Pacasmayo between 2015 and 2017. Data on landing volumes, temperature, and salinity were obtained from the IMARPE’s fixed station at such location. The oceanographic conditions were known with the temperature and sea surface salinity variables; a total of eight periods were identified, B was warm and of longer duration (12 months); while, E was transitional, of shorter duration (1 month). Hierarchical cluster analysis (HCA) with 75% similarity and Multidimensional Scaling (MDS) with stress 0.19 formed six groups (landing volumes) with the oceanographic periods, which were five warm and transitional, while one group was neutral. Panulirus gracilis S. “green spiny lobster” and Xiphopenaeus riveti B. “titi shrimp” showed an expansion in their space-time distribution around the warm periods; the opposite happened with Platyxanthus orbignyi “purple stone crab” in the transitional and neutral periods, which directly modified its accessibility and availability for artisanal fisheries.

Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Filosofia e Ciências Humanas, Programa de Pós-Graduação em Geografia, Florianópolis, 2020. O presente trabalho apresenta analisa a linha de costa do estado de Santa Catarina a partir da identificação e classificação dos promontórios rochosos, do comportamento da linha de costa em larga escala e do processo de transposição sedimentar juntamente com o monitoramento dos pontais arenosos situados na praia de Ponta das Canas, Florianópolis/SC, e na praia do Forte e praia da Enseada, São Francisco do Sul/SC. Foram utilizadas fotografias aéreas (1938, 1957, 1978, 1994, 2005, 2006 e 2010) e imagens de satélite (2003, 2009, 2010, 2011, 2012, 2013,2014, 2015, 2016 e 2017), estruturadas em um Sistema de Informações Geográficas, para o mapeamento das feições, como também o monitoramento topográfico mensal dos pontais arenosos (junho de 2016 a agosto de 2017). Como resultados, foram identificados e classificados, a partir de características morfológicas e influencias na circulação e transposição sedimentar, 107 promontórios rochosos em três classes: A) Pequenos; B) Médios; e C) Grandes. A linha de costa foi segmentada em cinco setores, de acordo com suas características geomorfológicas, classificadas em duas diferentes topologias (praias arenosas e costões rochosos), e no período de 36 anos (1978 a 2014) sua taxa de deslocamento apresentou característica média de estabilidade. Embora a estabilidade seja dominante em todo o período, o comportamento da linha de costa é variável entre os setores e dentro de cada um deles. Nos setores que possuem maior intervenção antrópica (1, 2, 3 e 4), a retração é mais representativa e no setor 5 ocorre progradação e a presença de uma feição sedimentar denominada travelling foreland migrando no sentido da deriva litorânea (sul ? norte). Em relação aos pontais arenosos, notou-se que os mesmos são regidos por um processo cíclico de deposição e erosão, acompanhado pela formação e remoção de laguna sazonal interna. Em ambos os pontais, mesmo que sob distintas condições e escalas, os processos sedimentares são similares, apresentando uma ciclicidade topográfica e morfológica. Assim, conclui-se que a linha de costa do estado de Santa Catarina possui diferentes comportamentos de deslocamento condicionados pelas características morfológicas, que também possibilita a ocorrência do processo de transposição sedimentar. Abstract: The present work analyzes the coastline of the state of Santa Catarina from the identification and classification of headlands, the behavior of the coastline on a large scale and the headland bypass together with the monitoring of sandy spits located on the Ponta das Canas beach, Florianópolis/SC SC, and Praia do Forte and Enseada Beaches, São Francisco do Sul / SC. Aerial photographs (1938, 1957, 1978, 1994, 2005, 2006 and 2010) and satellite images (2003, 2009, 2010, 2011, 2012, 2013,2014, 2015, 2016 and 2017) were used, structured in a Geographic Information, for the mapping of features, as well as the monthly topographic monitoring of sandy spits (June 2016 to August 2017). As a result, 107 headlands in three classes were identified and classified, based on morphological characteristics and influences on sedimentary circulation and transposition: A) Small; B) Medium; and C) Large. The coastline was segmented into five sectors, according to its geomorphological characteristics, classified in two different topologies (sandy beaches and rocky shores), and in the 36-year period (1978 to 2014) its displacement rate showed an average stability characteristic . Although stability is dominant throughout the period, the behavior of the coastline varies between sectors and within each sector. In the sectors with the greatest anthropic intervention (1, 2, 3 and 4), the retraction is more representative and in sector 5 there is progradation and the presence of a sedimentary feature called traveling foreland migrating in the direction of the coastal drift (south - north). In relation to sandy spits, it was noted that they are governed by a cyclical process of deposition and erosion, accompanied by the formation and removal of an internal seasonal lagoon. At both ends, even under different conditions and scales, the sedimentary processes are similar, presenting topographic and morphological cyclicality. Thus, it is concluded that the coast line of the state of Santa Catarina has different displacement behaviors conditioned by the morphological characteristics, which also allows the occurrence of the sediment by-pass.

This paper aims to improve the understanding of the marine sedimentation of the continental shelf and upper slope off southeast (SE) Brazil during the 20th century through the study of the deposition of natural radionuclides and its relationships with other sedimentological variables in a large set of sediment cores obtained during several oceanographic cruises. The main results of this study were the determination of sedimentation rates (0.49–3.73 cm yr−1) and its geographic distribution in the area. Together with 226Ra, mud, and carbonate content data, a picture emerged of a shelf and upper slope mostly dominated by lithoclastic sediments with a spatially heterogeneous grain size distribution, inputs of allochthonous sediments, and the presence of mid-outer shelf mud depocenters. Based on the age reconstruction of the cores, it was established that the area underwent no significant variations in sedimentation patterns during the period sampled by the cores, which corresponded to the last century. Nevertheless, there were clear geographical differences within the region; thus, the area was divided into sectors suggested by the assessed variables. The southern sector is marked by the presence of mud depocenters with high sedimentation rates and 226Ra levels connected to the Brazil Coastal Current (BCC) flow. The northern sector presents irregularly distributed sediments and modern contribution from processes associated with the Brazil Current (BC) and the exchange of materials with nearby coastal systems. The central sector functions as an interface between the processes observed in the southern and both sectors. The results highlight the need to reassess the prevalence of the reworking of Pleistocene sediments and the lack of current sediment sources in the area.

We present enigmatic toroidal carbonate concretions retrieved from 700 m water depth from two sites in the upper plateau of the Rio Grande Rise. The concretions have a diameter of ~15 cm and a central hole of ~5 cm, and were observed on top of loose bioclastic sand over an area of ~30 m2 at 0.5–1.5 m from one another. They consist of brown, porous, bioclastic grainstone, lacking internal structures. Grains consist of sand (

[cat] Donada l’alta sensibilitat de la regió central de la Mediterrània occidental a la variabilitat climàtica, s’han reconstruït les condicions de la mar superficials i profundes així com de les atmosfèriques pels darrers 2.700 anys. Les condicions marines han estat reconstruïdes a partir de multi-testimonis de sediment del nord de Menorca i les condicions atmosfèriques (hidroclimàtiques) en base a cinc registres d’espeleotemes de dues coves de Mallorca. La integració de la informació derivada d’aquests dos tipus d’arxius ha permès un millor enteniment de la interacció entre la mar superficial i profunda i l’atmosfera. Els principals períodes climàtics/històrics caracteritzats són: Període Talaiòtic (TP; fins el 123 BCE), Període Romà (RP; 123 BCE-470 CE(1)), Alta Edat Mitjana (EMA; 470 a 900 CE), Anomalia Climàtica Medieval (MCA; 900 a 1275 CE) i Petita Edat de Gel (LIA; 1275 a 1850 CE). Les Temperatures de la Mar Superficial (SST) s’han obtingut a partir de la ràtio Mg/Ca analitzada al foraminífer planctònic Globigerina bulloides (Cisneros et al., 2016), re- ajustant el calibratge de les SST per a la Mediterrània Occidental. La intensitat dels corrents fondos s’ha reconstruït a partir d’anàlisis de la mida de gra (paràmetre UP10, fracció >10 µm; Cisneros et al., 2019). Aquest paràmetre UP10 ha estat revalidat amb dades oceanogràfiques mostrejades durant els anys 2012-2014 mitjançant dos ancoratges instrumentats d’aigües profundes. La variabilitat hidroclimàtica ha estat reconstruïda emprant una metodologia que integra varis indicadors (anàlisi geoquímics i texturals) a les estalagmites. El període càlid més sostingut va tenir lloc durant el RP, el qual és seguit per una tendència de refredament interrompuda per vàries oscil·lacions a escala de centennis. Tot i que alguns períodes amb SST particularment càlides van tenir lloc durant la MCA, la LIA va estar marcadament inestable, amb alguns esdeveniments molt freds sobretot durant la segona meitat del període. Els esdeveniments més forts de formació d’aigua fonda van ocórrer durant intervals relativament càlids, com el RP, el final de la MCA i la primera part de la LIA. Per contra, les dades indiquen una reducció progressiva de la convecció durant l’EMA, resultant en esdeveniments durant la major part de la MCA. Els registres obtinguts de les estalagmites ha permès elaborar la primera reconstrucció regional de la variabilitat hidroclimàtica pels darrers 2.700 anys. Els registres indiquen condicions generalment humides per l’inici del RP, la primera meitat de l’EMA i per tota la LIA, en contrast amb les condicions més seques enregistrades pel RP tardà (anys 200-470 CE), la segona part de l’EMA (anys 700-900 CE) i tota la MCA. Dins de la LIA, al voltant de l’any 1622 CE, la existència d’un nivell detrític, enriquit en Ti a l’estalagmita Seán ha estat interpretat com un marcador d’inundacions associat a un esdeveniment extrem de pluja. La combinació integrada dels resultats derivats dels sediments marins i de les estalagmites suggereix condicions climàtiques no-estacionàries durant cadascun dels períodes estudiats dels últims 2.700 anys. Particularment durant el final del RP i la primera meitat de l’EMA, aquesta tesi suggereix una variabilitat climàtica més complexa i/o de més alta freqüència. L’EMA sembla haver estat caracteritzat com un període transició i, haver estat previ a una re-configuració atmosfèrica de diferents modes climàtics com el patró East Atlantic/West Russian i l’Oscil·lació de l’Atlàntic Nord. (1) BCE: anys abans de l’era comú/CE: anys de l’era comú, [eng] Surface-deep ocean and atmospheric reconstructions for the last 2.7 kyr have been performed taking the advantage of the high sensitivity of the central-western Mediterranean region. Ocean conditions have been reconstructed from sediment multicores recovered in the North Minorca and atmospheric conditions (hydroclimate) from five speleothem records of two Mallorca caves. The integration of this information has allowed a better understanding about the interaction between the surface-deep-sea and the atmosphere. The main climate/historical periods characterized are: Talaiotic Period (until 123BCE(1)), Roman Period (RP; 123BCE-470CE), Early Middle Ages (EMA; 470-900CE), Medieval Climate Anomaly (MCA; 900-1275CE) and Little Ice Age (LIA; 1275-1850CE). Sea-surface temperatures are derived from Mg/Ca-ratios analysed on planktonic foraminifera Globigerina bulloides (Cisneros et al., 2016) and deep-current intensity- changes from grain-size analysis (UP10-fraction; Cisneros et al., 2019). Hydroclimate variability has been reconstructed applying a multi-proxy approach (geochemical and textural analyses) on the stalagmites. The warmest sustained period occurred during the RP, followed by a general cooling trend interrupted by several centennial-scale oscillations. Although warm intervals took place during the MCA, the LIA was markedly unstable, with some very cold events mostly during its second half. The strongest deep-water formation events occurred during relatively warm intervals, such as the RP, the end of the MCA and the first part of the LIA. By contrast, our data indicate a progressive reduction in the overturning conditions during the EMA resulting in weaker deep-water formation events during most of the MCA. General wet conditions have been obtained for the early RP, the first half of the EMA and the entire LIA while drier conditions have characterized the late RP, the late EMA and the entire MCA. The combination of the results derived from marine sediments and stalagmites suggests non-stationary climate conditions during each period of the last 2.7 kyr. Particularly during the late RP and the first half of the EMA, more complex climate variability and/or with higher frequency seems to have occurred. The EMA seems to have been characterized like a transition period, previous to an atmospheric reconfiguration of different climate modes such as the East Atlantic/West Russian and NAO. (1) BCE: Before Common Era years/CE: Common Era years

FACEPE Esta tese foi desenvolvida no Atol das Rocas, oceano Atlântico tropical ocidental. Sua presença aumenta a produtividade por favorecer a mistura de águas nutridas em regiões iluminadas, acentuando a importância dos micro­organismos como cicladores de pequenas partículas, geralmente inacessíveis para os demais níveis tróficos. Para tanto, objetivamos ampliar o conhecimento sobre a diversidade do microplâncton, assim como os possíveis efeitos dos fatores ambientais sobre sua dinâmica espaço­temporal. Foram desenvolvidos três capítulos, o primeiro versa sobre a diversidade do microzooplâncton. Foram identificados 197 táxons e os grupos com maior riqueza foram Radiozoa (79), Copepoda (49, também o mais frequente), Tintinnina (42) e Foraminifera (12). A maior densidade total foi 63 683.3 ind m−3 (2010). Foi encontrado um alto índice de diversidade de Shannon (H’), variando de 3,57 a 3,81 bits ind−1. Os melhores indicadores para o atol das Rocas foram Codonellopsis orthoceros e Acanthodesmia viniculata (Tintininna), Orbulina universa (Foraminifera) e Acrocalanus gracilis (Copepoda), que são espécies características de águas tropicais oligotróficas. O segundo capítulo teve enfoque na diversidade de Radiozoa Polycystina e sua dinâmica temporal. Foram identificados 76 taxa entre as Ordens Nassellaria (12 famílias) e Spumellaria (9 famílias). Destes, 65,8% ocorreram apenas em 2014, ano de maior riqueza e densidade total, diferente do observado para o microzooplâncton total. Foi verificada diferença significativa para a densidade apenas entre anos. A temperatura foi o parâmetro mais explicativo, com maiores valores em 2010. Os nutrientes apresentaram valores mais altos em 2014, principalmente a sílica. Pode­se deduzir que a classe Polycystina foi mais bem­sucedida em 2014 onde elevados valores de nutrientes contribuíram positivamente para a maior abundância. O terceiro capítulo tratou sobre a diversidade e dinâmica espaço­temporal dos Dinoflagellata. Foram identificados 90 taxa distribuídos em seis Ordens. Gonyaulacales apresentou maior riqueza, com 34 espécies do gênero Tripos e 6 do gênero Ceratium (família Ceratiaceae). 2014 apresentou maior riqueza específica (69), enquanto, 2010 apresentou maior densidade total (19 125.17 ind m−3). Com destaque para Ceratium tripos var. tripos, Ceratium horridum var. buceros, Ceratium sp. e Tripos candelabrus, reforçando a importância da família Ceratiaceae, que foi mais abundante em todos os fatores (dia/noite, distância e ano). O ANOSIM indicou diferenças entre anos e período, com maior semelhança entre 2010 e 2014. 2014 foi o ano que apresentou maior riqueza, equitabilidade e diversidade. A noite apresentou maior equitabilidade e menor riqueza (79 noite/ 69 dia). 14 espécies apresentaram valor indicativo para 2010, 3 para 2014 e nenhuma pra 2012. Para o período, 2 foram indicativas do dia e 5 da noite. Os parâmetros apresentaram apenas variação anual, exceto para nitrato e fosfato. Conclui­se que a diferença anual foi mais marcante do que por período. 2014 e 2010 apresentaram maior semelhança e 2014 foi o mais favorável ao desenvolvimento dos Dinoflagellata, visto sua maior riqueza e diversidade. De um modo geral, percebemos que os grupos estudados se comportam de maneiras distintas dentro do contexto interanual, mostrando a importância desses grupos como indicadores ambientais de variações climáticas. This work was conducted at the Rocas Atoll, the only one in tropical Atlantic waters. Its presence increases the primary productivity mainly because It can promote water mixing in light­up regions, emphasizing the importance of microorganisms as small particle consumers, usually unavailable to the other trophic levels. Therefore, we aim to broaden the knowledge about microplankton diversity as well as the possible effects of environmental factors on their Spatio­temporal dynamics. Three parts have been developed, the first is about microzooplankton diversity. 197 taxa were identified and the richest groups were Radiozoa (79), Copepoda (49, also the most frequent), Tintinnina (42) and Foraminifera (12). The highest total density was 63 683.3 ind m−3 in 2010. A high Shannon diversity index (H ’) was found, ranging from 3.57 to 3.81 bits ind−1. The best indicators for Rocas atoll were Codonellopsis orthoceros and Acanthodesmia viniculata (Tintininna), Orbulina universa (Foraminifera) and Acrocalanus gracilis (Copepoda) which are characteristic species of oligotrophic tropical waters. The second part focused on the diversity of Radiozoa Polycystina and its temporal dynamics. 76 taxa were identified between the Nassellaria Orders (12 families) and Spumellaria Orders (9 families). Of these, 65.8% occurred only in 2014, the year of greatest richness and total density, different from that observed for total microzooplankton. A significant difference was found for density only between years. The temperature was the most descriptive parameter, with higher values in 2010. Nutrients had higher values in 2014, mainly silica. It can be deduced that the Polycystina class was most successful in 2014 where high nutrient values contributed positively to the highest abundance. The third part discusses the diversity and spatiotemporal dynamics of the Dinoflagellata. We identified 90 taxa distributed in six Orders. Gonyaulacales showed the higher richness, with 34 species of the genus Tripos and 6 of the genus Ceratium (Ceratiacea family). 2014 presented higher specific richness (69), while 2010 presented higher total density (19 125.17 ind m−3). Highlighting Ceratium tripos var. tripos, Ceratium horridum var. buceros, Ceratium sp. and Tripos candelabrus augmenting the importance of the Ceratiaceae family, which was more abundant in all factors (day/night, distance and year). The ANOSIM indicated differences between years and periods, with a greater similarity between 2010 and 2014. 2014 was the year with the highest richness, equitability, and diversity. The night exhibited higher equitability and lower richness (79 night / 69 day). 14 species presented indicative value for 2010, 3 for 2014 and none for 2012. For the period, 2 were indicative of the day and 5 of the night. The parameters presented only annual variation, except for nitrate and phosphate. It was concluded that the annual difference was more marked than the period. 2014 and 2010 were more similar and 2014 was the most favorable for the development of Dinoflagellata, given its greater richness and diversity. In general, we recognize that the groups studied behave in different ways within the temporal context, showing their importance as climatic change and environmental indicators.

The research on morphological changes caused by tsunamis has increased considerably in the last few years, yet the processes behind this phenomenon are still not fully understood. This paper analyzes and compares numerical simulations of morphological changes caused by the leading elevation and leading depression N-waves and tsunami waves propagating over a channel with a simple bed slope. The simulations were carried out by means of a coupled flow, sediment transport and morphodynamic two-dimensional-vertical numerical model. The modeled channel bed was composed of cohesionless sediments, and range of values for the bed slope and the wave height were employed. Four tsunami waveforms were studied to test the appropriateness of N-waves in modeling the morphological changes caused by tsunamis. On the modeling performed here, runup values were quite well represented by N waves. N-waves also represented qualitatively well the morphological changes caused by tsunamis. Yet, values of flow velocities and suspended sediment concentration showed more severe deviations from the modeled results corresponding with tsunami waves, very likely due to differences on the steepness of the waves. Therefore, even when N-waves can and have been used to represent tsunami runup and inundation distance, our results suggest that they should be considered with caution when intended to predict magnitudes of tsunami flow velocities and consequently morphological changes. The use of N waves to simulate morphological changes caused by tsunamis is not yet converging and must be further investigated. La investigación sobre los cambios morfológicos causados ​​por los tsunamis se ha incrementado considerablemente en los últimos años, sin embargo, los procesos detrás de este fenómeno aún no se conocen por completo. Este artículo analiza y compara simulaciones numéricas de cambios morfológicos causados ​​por ondas N de elevación y depresión principales y ondas de tsunami que se propagan a través de un canal con una pendiente de fondo simple. Las simulaciones se realizaron mediante un modelo numérico bidimensional-vertical acoplado de flujo, transporte de sedimentos y morfodinámica. El lecho del canal modelado estaba compuesto por sedimentos sin cohesión, y se empleó un rango de valores para la pendiente del lecho y la altura de la ola. Se estudiaron cuatro formas de onda de tsunami para probar la idoneidad de las ondas N en el modelado de los cambios morfológicos causados ​​por los tsunamis. En el modelado realizado aquí, los valores runup estaban bastante bien representados por ondas N. Las ondas N también representaron cualitativamente bien los cambios morfológicos causados ​​por los tsunamis. Sin embargo, los valores de las velocidades de flujo y la concentración de sedimentos suspendidos mostraron desviaciones más severas de los resultados modelados correspondientes a las olas de tsunami, muy probablemente debido a las diferencias en la inclinación de las olas. Por lo tanto, incluso cuando las ondas N pueden y han sido utilizadas para representar la carrera de tsunami y la distancia de inundación, nuestros resultados sugieren que deben considerarse con precaución cuando pretenden predecir magnitudes de velocidades de flujo de tsunami y, en consecuencia, cambios morfológicos. El uso de ondas N para simular cambios morfológicos causados ​​por tsunamis aún no converge y debe investigarse más a fondo. Universidad Nacional, Costa Rica Departamento de Física

Total phosphorus (TP) records reflect variations in input and burial of organic matter (OM) in coastal and shelf sediments . At Antarctic regions , TP levels are often derived from natural sources; however, with emergent human pressure at these regions, anthropogenic sources of TP may play an important role. At the Antarctic Peninsula , Admiralty Bay attracts great scientific and touristic interest, especially during austral summer months, thus being vulnerable to human activities. Currently, only scarce spatial distributions of TP are available for this key region, whereas no vertical distributions have been determined. To fill this gap, we investigated short ( sediment cores in ten areas along Admiralty Bay for TP contents. We produced the first TP vertical distributions and established site-specific background values (from 492 ± 13 to 932 ± 17 μg g −1 ), which are related to hydrodynamics, sedimentology , and natural inputs of P. We observed a gradual surface TP enrichment at all sites, mainly due to input of fresh OM. Benefiting from our background values, we employ the Phosphorus Pollution Index (PPI) to assess possible human impacts . Generally, the increase of PPI suggests natural inputs of P. However, PPI ≥ 1.3 found at the nearby Comandante Ferraz Research Station (Brazil) can be linked to recent (past 2–3 decades) treated sewage inputs in Martel Inlet. We suggest PPI as a proxy for preliminary assessments of anthropogenic impacts in coastal Antarctic regions experiencing increased human pressure.

Made available in DSpace on 2022-04-29T08:35:01Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-12-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) The evaluation of anthropogenic pressures in marine environments commonly involves sediments, water and marine biota. However, the evaluation of the quality of the beach sediment and sediments from shallow areas are scarce compared to sediments from deeper areas in environmental assessment studies. In this study polycyclic aromatic hydrocarbons and linear alkylbenzenes were assessed in sediments from shallow areas of the São Sebastião channel, southeastern Brazil. The channel is part of the Marine Protected Area of the Northern Coast of São Paulo State besides holds the largest petroleum terminal in South America further than three sewage outfalls. Despite the concentrations of these contaminants in the sediments were relatively low compared to those found in the sediments from deeper areas of the channel, suggesting low toxicity of the beach sediments, the contamination reflected the pattern of the sediments of the São Sebastião channel. Instituto de Biociências Universidade Estadual Paulista, Campus do Litoral Paulista, São Vicente Instituto Oceanográfico da Universidade de São Paulo, Praça do Oceanográfico, 191 Centro de Aquicultura Universidade Estadual Paulista Instituto de Biociências Universidade Estadual Paulista, Campus do Litoral Paulista, São Vicente Centro de Aquicultura Universidade Estadual Paulista FAPESP: 2016/17189-7.

This paper describes differences between Medieval Climate Anomaly (MCA) and present-day temperatures in the area composed of the Antarctic Peninsula, southern Patagonia, and the surrounding southern oceans. The investigation is conducted with the simulation results from the Community Earth System Model Last Millennium Ensemble (CESM-LME) considering the impact of each natural (volcanic activity and solar variability) and anthropogenic (greenhouse gas, ozone-aerosols and land use/land cover) individual forcing relative to the full forced simulations. Model results show generalized warming during the MCA in the study area. However, the simulated MCA temperatures are significantly colder than present-day mean values due to the influence of increased atmospheric greenhouse gas concentrations since the beginning of the modern Industrial Era in the ∼1850s. In fact, model runs in which only natural forcings were applied show that, in the absence of greenhouse gas forcing, present-day temperatures in the Antarctic Peninsula and southern Patagonia would be lower than or similar to those during the MCA. The study demonstrates the value of paleoclimate proxy–model comparisons but also highlights the limitations of current available proxy information to perform that integration in the study area.

El Golfo de Guayaquil es el principal estuario Tropical del Pacífico Sudeste, tiene importancia ecológica y económica; su variabilidad oceanográfica está regulada por fluctuaciones estacionales de época húmeda y seca. El área de estudio es una estación fija al noreste de la Isla Santa Clara en el Golfo de Guayaquil, en una columna de agua (0-75m), con una periodicidad mensual durante 3 años (2013 al 2015), aplicando metodologías estandarizadas para la colecta determinación de variables oceanográficas (temperatura, salinidad, oxígeno disuelto y nutrientes) y del fitoplancton (grupos funcionales-principales especies). Los resultados evidenciaron aguas más cálidas entre marzo a mayo, siendo más evidente en el último trimestre del 2015, relacionada con el evento El Niño-Oscilación del Sur (ENSO). La salinidad fue la variable más estable en la columna de agua. La distribución y concentración de oxígeno, presentó una capa superficial con alta concentración y otra capa subsuperfical con menor contenido de oxígeno. El nitrato fue el nutriente con mayor aporte significativo y con mayor variabilidad que el fosfato y silicato. La estructura y distribución del fitoplancton registró 166 especies durante los 3 años; 32 especies fueron más abundantes y correspondieron a las diatomeas. Su abundancia y diversidad fue dependiente de la profundidad. A nivel subsuperficial, no registró diferenciación en los 3 años. La relación del fitoplancton con las condiciones oceanográficas fue estadísticamente significativa, registró abundancias esporádicas de diatomeas (Skeletonema costatum, Nitzschia longissima, Chaetoceros curvisetus, C. affinis, C. didymus) en la capa superficial, con escasos dinoflagelados. Los máximos fueron ubicados en la proximidad de termoclina (10-20m). Gymnodinium y Gyrodinium (dinoflagelados) y el ciliado Myrionecta rubra fueron frecuentes. La abundancia de diatomeas indicó la buena sostenibilidad alimentaria en el Golfo, evidenciando que las condiciones térmicas de El Niño fueron relativamente débiles sobre los productores primarios., The Gulf of Guayaquil is the main tropical estuary of the Southeast Pacific, has ecological and economic importance. Its oceanographic variability is regulated by seasonal fluctuations in wet and dry seasons. The study area is a fixed station northeast of Santa Clara Island in the Gulf of Guayaquil, in a water column (0-75m), with a monthly frequency for 3 years (2013 to 2015), applying standardized methodologies for the Collection of oceanographic samples (temperature, salinity, nitrate and phosphate) and phytoplankton (functional groups - main species). The results showed warmer waters between March and May, being more evident in the last of 2015, related to the event El Niño-Southern Oscillation (ENSO). Salinity was a more stable parameter in the water column. The distribution and concentration of oxygen, presented a surface layer with high concentration and another subsuperfical layer with lower oxygen. The nitrate was the nutrient with greater significant contribution and with greater variability than the phosphate and silicate. The structure and distribution of phytoplankton recorded 166 species during the 3 years; 32 species were more abundant and corresponded to diatoms. Its abundance and diversity was dependent on depth. At subsurface level, there was no differentiation in the 3 years. The relationship of phytoplankton with oceanographic conditions was statistically significant, with sporadic abundances of diatoms (Skeletonema costatum, Nitzschia longissima, Chaetoceros curvisetus, C. affinis, C. didymus) on the surface layer, with few dinoflagellates. The maxima were located in the vicinity of thermocline and nutricline. Gymnodinium and Gyrodinium (dinoflagellates) and ciliated Myrionecta rubra were frequent. The abundance of diatoms indicated the good food sustainability in the Gulf, evidencing that the El Niño thermal conditions were relatively weak on the primary producers.

Marine plastic pollution is a global concern because of continuous release into the oceans over the last several decades. Although recent studies have made efforts to characterize the so-called plastisphere, or microbial community inhabiting plastic substrates, it is not clear whether the plastisphere is defined as a core community or as a random attachment of microbial cells. Likewise, little is known about the influence of the deep-sea environment on the plastisphere. In our experimental study, we evaluated the microbial colonization on polypropylene pellets and two types of plastic bags: regular high density polyethylene (HDPE) and HDPE with the oxo-biodegradable additive BDA. Gravel was used as control. Samples were deployed at three sites at 3,300 m depth in the Southwest Atlantic Ocean and left for microbial colonization for 719 days. For microbial communities analysis, DNA was extracted from the biofilm on plastic and gravel substrates, and then the 16S rRNA was sequenced through the Illumina Miseq platform. Cultivation was performed to isolate strains from the plastic and gravel substrates. Substrate type strongly influenced the microbial composition and structure, while no difference between sites was detected. Although several taxa were shared among plastics, we observed some groups specific for each plastic substrate. These communities comprised taxa previously reported from both epipelagic zones and deep-sea benthic ecosystems. The core microbiome (microbial taxa shared by all plastic substrates) was exclusively composed by low abundance taxa, with some members well-described in the plastisphere and with known plastic-degradation capabilities. Additionally, we obtained bacterial strains that have been previously reported inhabiting plastic substrates and/or degrading hydrocarbon compounds, which corroborates our metabarcoding data and suggests the presence of microbial members potentially active and involved with degradation of these plastics in the deep sea.

Rhodolith beds can contribute large amounts of CaCO3 to coastal environments, playing an important role in Carbon sequestration. The spatial distribution of rhodoliths is a consequence of their sensitivity to light intensity, currents, wave action, sedimentation rates, and salinity, whereas mesophotic, low sedimentation quiescent conditions are optimal. Although there is evidence of a clear relationship between hydrodynamics and rhodolith morphology and mobility, there are few studies relating wave action and rhodolith mobility. We aim to assess the mobility potential by waves, of the rhodoliths of the Abrolhos Shelf (Brazil), that contains the largest rhodolith field in the world. Based on the local wave climate and its propagation through the shelf, the rhodolith mobility potential was evaluated. Rhodolith mobility potential distribution is directly related to shelf morphology and incoming waves characteristics. Despite being restricted to deeper areas of the shelf (>20 m), rhodoliths in the area are mobilized by wave action, especially from the more energetic waves associated with storms. Waves can mobilize rhodoliths in the area, with mobility potential distribution being controlled by shelf morphology and seasonal wave climate. Largest areas of mobilization are observed during energetic waves conditions associated to the passage of cold fronts.

In this study we present an approach to calibrate a three-dimensional hydrodynamic model of a salt-wedge estuary, the Ararangua Estuary, southern Brazil, based on the Delft3D-FLOW model. The calibration was carried out in four steps to predict the vertical salinity structure along the estuary in an efficient and effective way. Skill assessment was used to evaluate the calibration quality. The model is forced by water-level elevation along the offshore open boundary and river-discharge inflows from the two major tributaries. The hydrodynamic model was calibrated using field observation of water level, currents and longitudinal salinity structure. Calibration was performed adjusting vertical grid resolution, bottom-friction coefficient and background eddy viscosity. The model achieves high skill values at water level and currents variations during a 113-day period (in 2008) covering a wide range of river discharge and tidal forcing. Water surface fluctuations obtained from the model are in good agreement with the field data. Modeled depth-averaged currents reproduce the temporal pattern of observed data. Longitudinal salinity structure is also well reproduced, although the vertical structure is more diffusive than the observations. Results also demonstrate that the model predicts the overall measured phenomena and the effects of the flash-flood event, with the discharge affecting water level, currents and salinity.

This paper investigates cold outbreaks that form offshore density currents within the whole mesoscale over the Western Mediterranean basin. Reflectivity radar and satellite images are used to detect clouds and precipitation that are associated with these density currents in the meso-α, meso-β, and meso-γover the Western Mediterranean basin (WMB). Version 3.3 of the WRF-ARW model is used to describe the formation and evolution of these density currents and to estimate their lifetime as well as horizontal and vertical scales. Based on the observations and simulations, this paper suggests that a new perspective could effectively be adopted regarding the WMB region delineated by the Balearic Islands, the northeastern Iberian Peninsula, and the Gulf of Lion, where inland cold outbreaks develop into density currents that move offshore and can produce precipitation ranging from raincells to rainbands at the whole mesoscale.

CAPES No final da década de 70 deu-se início as obras de construção do complexo industrial e portuário na área estuarina de Suape, distando cerca de 50 km da cidade do Recife (8°23′45′′ S e 34°58′4 ′′ W). A edificação do empreendimento vem causando uma série de impactos, entre eles: alteração da hidrodinâmica do local, supressão do manguezal, canalização de rios e obras de dragagens. O objetivo principal dessa pesquisa foi investigar o efeito da ação antrópica, variabilidade climática, ciclos de maré e espacialidade sobre a dinâmica da comunidade fitoplanctônica, presente nas águas adjacentes à referida região portuária. O estudo compreendeu 6 campanhas, 3 no período de estiagem e 3 no chuvoso, na preamar e baixa-mar em maré de sizígia. As amostras de água para análises biológicas (clorofila a, produtividade e densidade fitoplanctônica) e hidrológicas (oxigênio, material particulado em suspensão e nutrientes dissolvidos) foram coletadas na subsuperfície, utilizando garrafa de Niskin e rede de plâncton. A profundidade local com um ecobatímetro, a temperatura, salinidade, através de um CTD e a transparência, pelo disco de Secchi. A temperatura se manteve sempre elevada, registrando uma pequena amplitude térmica, a salinidade oscilou de 32.15 a 37.20. A concentração de nitrito e o silicato foram mais elevados no período chuvoso, enquanto que a amônia foi maior na estiagem, favorecendo o aumento da clorofila a e produtividade primária, que variaram de 0.02 a 2.45 mg m−3 e 0.34 a 4.32 mgC m−3 ha−1 , respectivamente. A clorofila a < 20 µm foi a que mais contribuiu com o ecossistema estuarino, correspondendo a 88.57 %. A densidade e o biovolume celular das diatomáceas e cianobactérias foram maiores no período chuvoso, diretamente relacionadas com o nitrito, silicato e mps. Enquanto o número de célula por litro e biovolume dos dinoflagelados foram maiores período de estiagem, influenciados positivamente pela salinidade e temperatura, sendo esse filo o mais produtivo, com destaque para a espécie Gymnodinium sp.. Foram identificados 127 táxons, agrupados nos filos Bacillariophyta (75.8%), Miozoa (14.17%), Cyanobacteria (7.08%), Chlorophyta (2.36%) e Euglenozoa (0.78%). As espécies Bacillaria paxillifera (O.F.Müller) T.Marsson, Oscillatora sp., Gymmnodinium sp., Protoperidinium sp.5, Pseudo-nitszchia pungens (Grunow ex Cleve) Hasle, foram as mais representativas. Quanto ao aspecto ecológico, 55.91% dos táxons foram planctônicos marinhos, 32.25% ticoplanctônicos neríticos, 6.35% dulcícolas e 5.37% estuarinas. A variabilidade climática e as constantes alterações antrópicas levaram a uma menor contribuição continental, aumento da interferência marinha, diluição dos nutrientes, diminuição na produtividade primária e modificação na estrutura da comunidade fitoplanctônica, podendo causar danos aos demais elos da teia trófica do sistema. In the late 1970s, construction work began on an industrial and port complex in the estuary area of Suape, about 50 km from Recife (8°23′45′′ S e 34°58′4 ′′ W). The construction of the project has been causing a series of impacts, including: alteration of the hydrodynamics of the site, suppression of the mangrove, channeling of rivers and dredging works. The main objective of this research was to investigate the effect of anthropic action, climate variability, tidal cycles and spatial on the dynamics of the phytoplankton community present in the waters adjacent to the port region. The study comprised 6 campaigns, 3 in the dry season and 3 in the rainy season, at high tide and low tide at spring tide. Water samples for biological (chlorophyll a, productivity and phytoplankton density) and hydrological (oxygen, particulate matter suspended and dissolved nutrients) analyzes were collected at the subsurface using a Niskin bottle and plankton net. Local depth with an echo sounder, temperature, salinity through a CTD and transparency by Secchi disc. The temperature always remained high, registering a small thermal amplitude, the salinity oscillated from 32.15 to 37.20. Nitrite and silicate concentrations were higher in the rainy season, while ammonia was higher in the dry season, favoring the increase of chlorophyll a and primary productivity, which ranged from 0.02 to 2.45 mg m−3 and 0.34 to 4.32 mgC m−3 ha−1 , respectively. Chlorophyll a < 20 µm was the major contributor to the estuarine ecosystem, corresponding to 88.57%. The density and cell biovolume of diatoms and cyanobacteria were higher in the rainy season, directly related to nitrite, silicate and mps. While the cell number per liter and biovolume of the dinoflagellates were longer drought period, positively influenced by salinity and temperature, this phylum was the most productive, especially Gymnodinium sp.. 127 taxa were identified, grouped in the Bacillariophyta phylum ( 75.8%), Miozoa (14.17%), Cyanobacteria (7.08%), Chlorophyta (2.36%) and Euglenozoa (0.78%). The species Bacillaria paxillifera (O.F.Müller) T.Marsson, Oscillatora sp., Gymmnodinium sp., Protoperidinium sp.5, and Pseudo-nitszchia pungens (Grunow ex Cleve) Hasle were the most representative. Regarding the ecological aspect, 55.91% of the taxa were marine planktonic, 32.25% neritic ticoplanktonic, 6.35% freshwater and 5.37% estuarine. Climatic variability and constant anthropogenic changes have led to lower continental contribution, increased marine interference, nutrient dilution, decreased primary productivity and modification of the phytoplankton commu- nity structure, which may damage the other links in the food web of the system.