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Registros recuperados: 242
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Influence of salinity variations on zooplankton community in el-mex bay, alexandria, egypt OceanDocs
Zakaria, H.Y.; Radwan, A.A.; Said, M.A..
El-Mex Bay receives a heavy load of waste waters (7×109 m3/year) both directly from industrial outfalls and indirectly from Lake Maryuit via El-Mex Pumping Station. Zooplankton samples were collected bimonthly from seven stations during the period March 2005 to January 2006 to illustrate the influence of salinity variations on the abundance and community structure of zooplankton in El-Mex Bay waters. Based on the salinity values, four water types are identified: the mixed land drainage (L) of salinity < 10ppt, mixed water (M) of salinity range 10 to 30ppt, diluted sea water (D) of salinity range 30 to 38.5 ppt and Mediterranean Sea water (S) of salinity > 38.5. The highest zooplankton standing crop (106.6×103 ind/m3) was recorded in the mixed land...
Tipo: Journal Contribution Palavras-chave: Field Study; Zooplankton; Salinity; Zooplankton; Salinity; Http://aims.fao.org/aos/agrovoc/c_15490; Http://aims.fao.org/aos/agrovoc/c_6751.
Ano: 2007 URL: http://hdl.handle.net/1834/2211
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Composición y variación estacional del fitoplancton, zooplancton y microbentos en el estuario interior del Golfo de Guayaquil, durante el año 2003 OceanDocs
Gualancañay, E.; Tapia, M.E.; Naranjo, Ch..
El presente trabajo comprende el estudio de la distribution cualitativa y cuantitativa del fitoplancton en el Golfo de Guayaquil, durante dos épocas: Húmeda y seca. El propósito del presente trabajo con respecto al zooplankton está orientado a conocer los cambios en la composición, abundancia y diversidad del zooplancton y en particular el Phyllum Chaetognatha con el objetivo de relacionar la distribución de las especies de Quetognatos con los parámetros físicos. En lo relacionado al estudio del microbentos, se pretende estudiar la composición específica y la abundancia relativa de las especies de la microflora béntica y de la microfauna bentónica y su relación con factores ambientales.
Tipo: Journal Contribution Palavras-chave: Community composition; Seasonal variations; Phytoplankton; Diatoms; Biomass; Zooplankton; Microorganisms; Benthos; Geographical distribution; Estuaries; Phytoplankton; Biomass; Zooplankton; Benthos; Geographical distribution; Estuaries; Diatoms; Microorganisms; Http://aims.fao.org/aos/agrovoc/c_13344; Http://aims.fao.org/aos/agrovoc/c_926; Http://aims.fao.org/aos/agrovoc/c_15490; Http://aims.fao.org/aos/agrovoc/c_878; Http://aims.fao.org/aos/agrovoc/c_5083; Http://aims.fao.org/aos/agrovoc/c_2673; Http://aims.fao.org/aos/agrovoc/c_32657; Http://aims.fao.org/aos/agrovoc/c_4807.
Ano: 2004 URL: http://hdl.handle.net/1834/2283
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Distribution and long-term historical changes of zooplankton assemblages in lake manzala (south mediterranean sea, egypt) OceanDocs
Mageed, A.A.A..
The northern lakes of Egypt have always acted as a buffer zone between the drainage system in the Nile Delta and the Mediterranean Sea. Most of these lakes are exposed to high inputs of industrial and domestic wastewater as well as agricultural drainage water, like Lake Manzala, which influence the living organisms on the long run. Samples of zooplankton were collected monthly from ten stations among Lake Manzala showing the different microhabitat of the lake. A one year monitoring has been carried out. Lake Manzala has been changed from marine ecosystem to eutrophic, nearly, freshwater system with the dominance of rotifers (cal ~ 97%). Twenty newly recorded zooplankton taxa were found for the first time in the lake during the study, while thirteen taxa...
Tipo: Journal Contribution Palavras-chave: Field Study; Zooplankton; Zooplankton; Http://aims.fao.org/aos/agrovoc/c_15490.
Ano: 2007 URL: http://hdl.handle.net/1834/1901
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Variabilite mensuelle du zooplancton et de l'ichtyoplancton dans le golfe de Tunis OceanDocs
Missaoui, H.; El Abed, A.; M'rabet, R.; Romdhane, M.S.; Zarrad, R.; Jarboui, O..
Monthly variability of zooplankton and ichthyoplankton abundance and composition were studied in 6 stations in the Gulf of Tunis between February 2003 and January 2004. Plankton trawls were horizontal, in surface and at night. Study area seems to be influenced by climatic conditions and the outflow of Majreda River that affect the surface temperature and salinity. Copepods, with many abundance peaks in the year, formed the most abundant group (84%) followed by cladocerans (8%) and chaetognaths (3%). The appendicularians, cladocerans and medusae had swarms in the summer, the creseis and the chaetognths in the autun and the zoae larvae in the spring. The highest fish spawning periods was in summer then the highest larva abundance was in winter and...
Tipo: Journal Contribution Palavras-chave: Community composition; Fish larvae; Ichthyoplankton; Temporal variations; Zooplankton; Zooplankton; Fish larvae; Http://aims.fao.org/aos/agrovoc/c_15490; Http://aims.fao.org/aos/agrovoc/c_2924.
Ano: 2004 URL: http://hdl.handle.net/1834/4242
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Procesos planctónicos en el Golfo de Guayaquil (Campo Amistad) julio-agosto/2001 OceanDocs
Torres Ch., G.; Calderón, T.; Mero, M.; Franco, V..
El presente trabajo es una contribución al estudio del fitoplancton y zooplancton marino-estuarino y su relación con las condiciones ambientales físico-químicas presentes en el entorno de la plataforma Amistad de producción de gas (Campo Amistad - Golfo de Guayaquil Externo), realizada por el Instituto Oceanográfico de la Armada en el B/I ORION durante julio-agosto del 2001.
Tipo: Journal Contribution Palavras-chave: Biomass; Chlorophylls; Nutrients (mineral); Zooplankton; Phytoplankton; Environmental assessment; Production platforms; Biomass; Zooplankton; Phytoplankton; Chlorophylls; Environmental assessment; Http://aims.fao.org/aos/agrovoc/c_926; Http://aims.fao.org/aos/agrovoc/c_15490; Http://aims.fao.org/aos/agrovoc/c_13344; Http://aims.fao.org/aos/agrovoc/c_1577; Http://aims.fao.org/aos/agrovoc/c_37751.
Ano: 2004 URL: http://hdl.handle.net/1834/2285
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Distribución de quistes de Alexandrium catenella y otros dinoflagelados en sedimentos de la zona sur-austral de Chile OceanDocs
Lembeye, Georgina.
During the expeditions Cimar - Fiordos 2, 3 and 4 (1996, 1997 and 1999), samples of marine sediments were collected in Southern Chile, between Melinka (Lat. 43° 45' S) and Beagle Channel (Lat. 54° 56' S) to study the distribution and abundance of dinoflagellate cysts, particularly the toxic dinoflagellate Alexandriurn catenella. Samples were collected from 33 stations at depths of 1 to 15 meters. The study included photographic record and taxonomic identification of cysts to genus and, whenever possible, to species, with emphasis on the identification of cysts of A. catenella. Cysts from samples collected in cruises 3 and 4, were incubated in f/2-Se culture medium at 13 °C with controlled photoperiod (14:10, L:D), to induce germination and confirm species...
Tipo: Journal Contribution Palavras-chave: Sediments; Quantitative distribution; Cysts; Zooplankton; Cysts; Zooplankton; Http://aims.fao.org/aos/agrovoc/c_34811; Http://aims.fao.org/aos/agrovoc/c_15490.
Ano: 2004 URL: http://hdl.handle.net/1834/4126
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Caracterización biológica de la bahía de Jaramijó en la costa Ecuatoriana OceanDocs
Gualancañay, E.; Tapia, M.E.; Naranjo, Ch.; Cruz, M.; Villamar, F..
Para el estudio biológico y ambiental de la bahía de Jaramijó en los componentes fitoplancton, zooplancton, microbentos y macrobentos, se analizaron 15 estaciones provenientes de tres niveles entre 10 y 20 metros de profundidad y dividido en tres perfiles paralelos a la costa, durante las estaciones seca y lluviosa del año 2008. El fitoplancton y zooplancton resultaron muy abundantes durante la estaciòn lluviosa y menos abundante en la estación seca del año 2008. Predominaron las especies de diatomeas: Bacteriastrum hyalinum, Leptocylindrus danicus, Rhizósolenia stolterfothii, Chaetoceros affinis y Ch. curvisetus y la presencia de dinoflagelados y cianobacterias fue escasa dinoflagelados. En general las especies halladas son típicas de una mezcla de masas...
Tipo: Journal Contribution Palavras-chave: Phytoplankton; Zooplankton; Biogeography; Biomass; Marine molluscs.
Ano: 2010 URL: http://hdl.handle.net/1834/4212
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Variación interanual del mesozooplancton en la plataforma bonaerense en primavera: introducción de nuevas metodologías para su análisis OceanDocs
Di Mauro, R..
The distribution and abundance of mesozooplankton (specially copepod, cladoceran and appendicularian species) of the Buenos Aires shelf obtained in spring, during the years 2002, 2003 and 2004, were analysed. A small bongo net provided with 67 and 220 µm meshes, was employed in order to obtain a complete representation of the size spectrum of the mesozooplankton. The analysis included both the traditional optical method and the a new automatic image analysis (ZooImage). The results were related with the oceanographic conditions, which were, in general similar to the mean conditions for the study area. The finer mesh (67 µm) allowed a more accurate estimation of the abundance and biomass of small copepod species ( 1mm total length), producing the tick mesh...
Tipo: Theses and Dissertations Palavras-chave: Zooplankton; Abundance; Biomass; Annual variations; Fish larvae; Imaging techniques; Oceanographic data; Environmental conditions; Salinity; Temperature; Water masses.
Ano: 2011 URL: http://hdl.handle.net/1834/4204
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Variaciones temporales del phylum quetognatos en las estaciones fijas La Libertad y Manta, Ecuador durante el evento El Niño 1997-1998 y años 2002-2003 OceanDocs
Naranjo, Ch..
El presente estudio se desarrolló mediante muestreos mensuales de zooplankton en las estaciones fijas La Libertad y Manta localizadas a 10 y 8 millas costa afuera respectivamente. Se analizaron un total de 150 muestras de zooplankton en La Libertad y Manta durante 1997-1998 considerado un evento El Niño extraordinario y en los años 2002-2003, período que presentaron condiciones oceanográficas de inestabilidad. La prueba estadística determinó que existen cambios temporales en los patrones de distribución y abundancia en las especies de Quetognatos, aceptándose la hipótesis nula, el cual estuvo influenciado por las condiciones oceanográficas y época estacional, siendo más notorio en la estación fija La Libertad durante el período en estudio. El índice de...
Tipo: Journal Contribution Palavras-chave: Temporal variations; Zooplankton; Abundance; Species diversity; Zooplankton; Species diversity; Http://aims.fao.org/aos/agrovoc/c_15490; Http://aims.fao.org/aos/agrovoc/c_33954.
Ano: 2009 URL: http://hdl.handle.net/1834/3357
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Composición y abundancia del macrozooplancton e ictioplancton en el Estrecho Bransfield, durante el verano austral 1998 OceanDocs
Ortega, D..
Durante la realización de la VII Expedición Antártica Ecuatoriana, efectuada entre diciembre de 1997 y marzo de 1998. Se realizó un crucero oceanográfico en el Estrecho Bransfield a bordo del Bae/Orión, colectándose muestras de macrozooplancton obtenidas por arrastres oblicuos con redes tipo bongo de 500μ hasta una profundidad de 300 m. Este estudio se efectuó con el fin de conocer la distribución y composición del macrozooplancton e ictioplancton en el Estrecgo Bransfield. La biomasa zooplanctónica, registró la mayor concentración 6 913 org.(1000m3)-1, cercano al área de la plataforma Antártica (Península Antártica), donde la temperatura fue de (-1° C). De los organismos zooplanctónicos identificados, las salpas con 62%, copépodos 9% eufáusidos 8%, fueron...
Tipo: Journal Contribution Palavras-chave: Composition; Distribution; Abundance; Zooplankton; Ichthyoplankton; Cruises; Distribution; Zooplankton; Http://aims.fao.org/aos/agrovoc/c_35773; Http://aims.fao.org/aos/agrovoc/c_15490.
Ano: 1998 URL: http://hdl.handle.net/1834/3854
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Communautés zooplanctoniques de la lagune de Grand-Lahou (Cote d'Ivoire). OceanDocs
Kouassi, A.M.; N'doua, E.; Adingra, A.A..
Le peuplement zooplanctoniques de la lagune de Grand-Lahou inventorié de janvier à décembre 2004 est riche de 65 taxons regroupés en 4 groupes (Copépodes, Rotifères, Cladocères et un groupe de divers organismes zooplanctoniques) et 3 communautés (continentale, lagunaire et marine).
Tipo: Journal Contribution Palavras-chave: Zoobenthos; Zooplankton.
Ano: 2008 URL: http://hdl.handle.net/1834/5744
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Resultados preliminares sobre zooplancton y su luminiscencia en la región oriental del Mar Caribe OceanDocs
Artiomkin, A. S.; Flilimonov, V. S.; Baldina, E. P.; Greze, V. N..
142 samples of the eastern of the Caribbean Sea were analysed.The study of samples showed that there are not distintions in the differents zones investigated of plankton productivity and that the plankton composition and distribution are monotone in all cross section. The experiment established that thirty species of various zooplankton groups are luminiscent. The maximun of luminiscense occurs at 50 m depth. The development of electronic equipment are considered.
Tipo: Journal Contribution Palavras-chave: Zooplankton; Luminescent organs; Zooplankton; Luminescence.
Ano: 1969 URL: http://hdl.handle.net/1834/5713
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Comunidades del plancton en la Caleta Aeolian de la Isla Baltra - Galápagos (Ecuador), durante 2005 OceanDocs
Naranjo, Ch.; Tapia, M.E..
El propósito del trabajo es determinar la composición, abundancia de los grupos dominantes del fitoplancton y zooplancton, establecer las especies de Quetognatos y su relación con la temperatura superficial del mar durante marzo de 2005 correspondiente a la época húmeda.
Tipo: Journal Contribution Palavras-chave: Plankton; Primary production; Biological production; Phytoplankton; Zooplankton; Biomass; Abundance; Community composition; Fish eggs; Surface temperature; Plankton; Primary production; Biological production; Phytoplankton; Zooplankton; Biomass; Http://aims.fao.org/aos/agrovoc/c_5950; Http://aims.fao.org/aos/agrovoc/c_34329; Http://aims.fao.org/aos/agrovoc/c_36649; Http://aims.fao.org/aos/agrovoc/c_13344; Http://aims.fao.org/aos/agrovoc/c_15490; Http://aims.fao.org/aos/agrovoc/c_926.
Ano: 2007 URL: http://hdl.handle.net/1834/2346
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El rol del frente de mareas de Península Valdés en el control de la comunidad zooplanctónica OceanDocs
Derisio, C..
The Península Valdés tidal front was studied in its rol in the control of the spatial distribution, abundance, assemblages, diversity and life histories of the zooplankton community using samples from two oceanographic surveys. Although the front showed in general high zooplankton abundances, highest values, mainly due to the presence of immature stages of copepods, were recorded in the transitional and stratified zones coinciding with highest values of chlorophyll a. The zooplankton groups showed a distinctive spatial distribution across the front. The results showed that this front did not exert any control on zooplankton composition and diversity, but did on the abundance. In the homogeneous zone the harpacticoid copepods were more abundant, followed by...
Tipo: Theses and Dissertations Palavras-chave: Zooplankton; Ecological associations; Oceanic fronts; Abundance; Species diversity; Hydrography; Vertical migrations; Copepoda; Cladocera; Marine environment.
Ano: 2012 URL: http://hdl.handle.net/1834/4777
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Efecto de la predación de Noctiluca scintillans Macartney, Sagitta friderici Ritter-Záhony y larvas de Engraulis anchoita Hubbs-Marini sobre la comunidad planctónica costera bonaerense OceanDocs
Sato, N.E..
Studied the effect of the predation of Noctiluca scintillans, Sagitta friderici and larvae of Engraulis anchoita in planktonic community of the coastal waters off Buenos Aires province from samples obtained of a permanent station EPEA (38°28’ S, 57°41’ W, 48 m depth) from March 2000 through April 2001. The composition of the diet of the three species predators considering appearances quantitative and qualitative was determined. It found that N. scintillans consumed mainly diatoms and copepod eggs. The alimentary index varied between 27.50% and 77.00%. The highest value corresponded to September, 2000. The analyses of the diets of S. friderici and of the larvae of E. anchoita indicated that both consume mainly different stages of development of the same...
Tipo: Theses and Dissertations Palavras-chave: Zooplankton; Fish larvae; Feeding behaviour; Predation; Seasonal variations; Food organisms; Predator prey interactions; Engraulis anchoita; Noctiluca scintillans; Sagitta friderici; Marine environment.
Ano: 2008 URL: http://hdl.handle.net/1834/4778
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Ecología trófica de estadios juveniles de los esciénidos dominantes en el estuario de Bahía Blanca. Pescadilla de red (Cynoscion guatucupa) y corvina rubia (Micropogonias furnieri) OceanDocs
Sardiña, P..
Striped weakfish (Cynoscion guatucupa)and whitemouth croaker(Micropogonias furnieri)are one of the most important coastal resources of Bahia Blanca Estuary (Buenos Aires Prov., Argentina). The aims of this thesis were: 1, to analyze the population and morphological characteristics of the juveniles stages of the striped weakfish and the whitemouth croaker living in Bahia Blanca Estuary; 2, to describe the dietary habits of the juveniles of these two species; 3, to analyze the ontogenetic and seasonal diet changes in both species, and 4, to study the feeding interrelationships between both species as well as the interrelationships between each species and its prey. In view of the mentioned objectives, diet was evaluated taking into account the following...
Tipo: Theses and Dissertations Palavras-chave: Brackishwater environment; Brackishwater fish; Comparative studies; Feeding behaviour; Trophic relationships; Zooplankton; Juveniles; Feeding behaviour; Zooplankton; Brackishwater environment; Juveniles; Http://aims.fao.org/aos/agrovoc/c_10778; Http://aims.fao.org/aos/agrovoc/c_15490; Http://aims.fao.org/aos/agrovoc/c_1050; Http://aims.fao.org/aos/agrovoc/c_25393.
Ano: 2004 URL: http://hdl.handle.net/1834/2595
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Modèle couple dynamique -écologie pour la lagune de Bizerte OceanDocs
Bejaoui, B.; Harzallah, A.; Moussa, M.; Chapelle, A..
This work concerns the development of a three dimensional hydroecological model based on two nutrient elements, nitrogen and phosphorus.The hydrodynamic model is 3D forced by monthly climatic data of NOAA. The ecological model was developed based on two nutrient elements, nitrogen and phosphorus in interaction with the phytoplankton and zooplancton. The ecological model is made up with two compartments, the water column and the sediment layer. Eight state variables are used to characterize the water column and six state variables for the sediment layer. As a first application, the model was tested on the Bizerte Lagoon. A comparison between simulations and observations showed that the model can reproduce with satisfactory way the observations carried out...
Tipo: Journal Contribution Palavras-chave: Dissolved oxygen; Hydrodynamics; Models; Nutrient cycles; Phytoplankton; Zooplankton.
Ano: 2008 URL: http://hdl.handle.net/1834/4264
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Estimación de tasas de ingestión de Mnemiopsis leidyi (Ctenophora: Lobata) en condiciones de laboratorio OceanDocs
Bertelo, M.I.; Giberto, D.A.; Schiariti, A.; Bianca, F.; Suárez, J.; Mianzan, H.W..
The first results in the development of a standardized methodology to estimate Mnemiopsis leidyi intake rates and their impact on fish recruitment are presented. M. leidyi capability to consume lyophilized fish eggs and level of consumption of such type of preys, Artemia nauplii and rotifera were assessed. Although M. leidyi can consume lyophilized fish eggs, intake rates were extremely low, often null and in all cases lower than those estimated for the other types of preys offered. The increase of feeding rate on each prey was proportional to ctenophores size growth. The results observed suggest that consumption of fish eggs would not affect recruitment. However, there is not a uniform methodology in the literature that allows for standardized...
Tipo: Journal Contribution Palavras-chave: Artificial feeding; Recruitment; Fish eggs; Controlled conditions; Zooplankton.
Ano: 2013 URL: http://hdl.handle.net/1834/5485
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Relación fitoplancton-zooplancton en el Pacífico Ecuatorial (Ecuador), durante septiembre 2001 OceanDocs
Torres, G.; Mero, M.; Calderón, T.; Franco, V.; Salazar, E..
El presente trabajo es una contribución al conocimiento de la bio-oceanografía del mar ecuatoriano, forma parte del proyecto de Monitoreo de las condiciones oceanográficas en el mar ecuatoriano y su relación con eventos de El Niño, realizadas en el B/I ORION del Instituto Oceanográfico de la Armada (INOCAR) en septiembre-octubre 2001, como un aporte a la comunidad científica.
Tipo: Journal Contribution Palavras-chave: Phytoplankton; Diatoms; Zooplankton; Biological production; Upwelling; Population density; Cruises; Abundance; Geographical distribution; Biological production; Geographical distribution; Phytoplankton; Zooplankton; Population density; Diatoms; Http://aims.fao.org/aos/agrovoc/c_36649; Http://aims.fao.org/aos/agrovoc/c_5083; Http://aims.fao.org/aos/agrovoc/c_13344; Http://aims.fao.org/aos/agrovoc/c_15490; Http://aims.fao.org/aos/agrovoc/c_6112; Http://aims.fao.org/aos/agrovoc/c_32657.
Ano: 2004 URL: http://hdl.handle.net/1834/2297
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Un système d'indicateurs de durabilité des pêcheries côtières comme outil de gestion intégrée des ressources halieutiques sénégalaises OceanDocs
Thiao, Djiga.
Cette thèse est axée sur une analyse de la durabilité des pêcheries côtières qui aboutit sur la proposition d’un système d’indicateurs comme outil de gestion intégrée des ressources halieutiques sénégalaises. L’objectif est d’encourager une meilleure gouvernance de ces systèmes halieutiques et côtiers dont l’exploitation est caractérisée par la complexité, la multiplicité et l’interactivité de plusieurs facteurs écologiques, économiques et sociaux. La stratégie adoptée est fondée sur l’approche systémique à travers une vision multidimensionnelle et multi-acteurs s’appuyant sur le modèle PER (pression-état-réponse). Le diagnostic reflète une détérioration générale de l’état des écosystèmes côtiers nécessitant des mesures d’ajustement de la...
Tipo: Theses and Dissertations Palavras-chave: Sustainable fishing; Inshore waters; Coastal zone management; Fisheries resources; Ecosystem management; Hydrology; Phytoplankton; Flora; Coastal environment; Sustainable development; Zooplankton; Ecology; Temperature; Salinity; Tourism; Rivers; Upwelling.
Ano: 2009 URL: http://hdl.handle.net/1834/5002
Registros recuperados: 242
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