47 resultados para Algas Marinas-Tamaulipas


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Contiene los trabajos presentados, el programa científico y el perfil de instituciones marinas cubanas. Contains the papers presented, the scientific program and the profile of Cuban marine institutions.

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Además de sus conocidos aportes a la geología, la paleontología y la biogeografía de ecosistemas terrestres de la región pampeana y la Patagonia (Argentina), Darwin realizó notables y poco difundidas contribuciones al conocimiento de los ambientes marinos costeros del actual territorio argentino y de los organismos que habitan en ellos. La intimidad de Darwin con el mar se advierte en toda su obra: en el Viaje y en el Origen igual que en numerosos trabajos de investigación realizados y publicados a su regreso a Inglaterra. Entre 1846 y 1854 dio a conocer una extensa obra sobre cirrípedos o cirripedios, que sentó las bases del estudio de esos crustáceos y, aún hoy, es bibliografía obligada de los taxónomos. Su trabajo sobre la estructura y distribución de los arrecifes coralinos de 1842, es considerado un documento fundacional del conocimiento sobre el origen de los atolones. Los moluscos fueron igualmente objeto de publicaciones y cartas entre 1848 y 1871. La difundida imagen de Darwin sentado ante un escritorio escribiendo sus libros lleva a olvidar que pasaba también mucho tiempo con el microscopio. En el Viaje del Beagle incluyó párrafos sobre aves marinas, lo mismo que sobre briozoos o briozoarios, y en El origen, explicó sus pensamientos acerca de la migración de los ojos en los lenguados. Dedicó especial atención a las algas gigantes o sargazos marinos de Tierra del Fuego (donde se los conoce por cachiyuyos). Se incluyen los siguientes trabajos de divulgación científica -Darwin y los briozoos; -Darwin y el desarrollo larval de crustáceos; -Sobre Cirripedios; De Darwin a los acelerómetros; -Los peces de cara torcida; -La incursión en la costa sur de Buenos Aires.

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Con la ayuda de los sensores remotos y los sistemas de posicionamiento geográfico, los científicos están descubriendo varias facetas sobre las vida de las tortugas marinas. Se describe el método para realizar el siguimiento satelital, sus migraciones, y se dan las características de las especies de tortugas marinas encontradas en aguas costeras de la Argentina. Este trabajo de divulgación científica hace hincapié en la importancia de su conservación, según la Unión Internacional para la Conservación de la Naturaleza, éstas se encuentran en peligro o en peligro crítico de extinción en todo el mundo. Se incluyen al final otras lecturas sugeridas sobre el tema.

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Los objetivos de las Áreas Marinas Protegidas (AMP) son conservar la diversidad biológica, mantener procesos ecológicos y asegurar el uso sustentable de los recursos. Se señalan las amenzas a la biodiversidad marina y algunos programas tendientes a mejorar el sistema de áreas marinas protegidas en la Argentina (oceáno Atlántico sudoccidental). Se incluyen lecturas sugeridas y el mapa de AMP de Argentina (Océano Atlántico sudoccidental).

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Composition, abundance and environmental characteristics of the sea-weed resources of Mozambique were investigated along the whole Mozambican sea shore between May, 1979 and November, 1980. The limits of distribution of tropical algae were identified and located close to parallel 21 degree 00'S. Important concentrations of sea-weeds were found in the southern region, but only the Euchema resource in the coast of Cabo Delgado looked promising for commercial exploitation. Biological studies of Euchema were undertaken, the results of which permit the recommendation of a strategy for immediate harvesting which could yield 400-500 tons annually. Further proposals for the culture of sea-weeds are also included.

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The 17th Annual Sea Turtle Symposium was held at the Delta Orlando Resort in Orlando, Florida U.S.A. from March 4-8, 1997. The symposium was hosted by Florida Atlantic University, Mote Marine Laboratory, University of Central Florida, University of Florida, Florida Atlantic University and the Comité Nacional para la Conservación y Protección de las Totugas Marinas. The 17th was the largest symposium to date. A total of 720 participants registered, including sea turtle biologists, students, regulatory personnel, managers, and volunteers representing 38 countries. In addition to the United States, participants represented Australia, Austria, the Bahamas, Bonaire, Bermuda, Brazil, Canada, Colombia, Costa Rica, Croatia, Cuba, Cyprus, Dominican Republic, Ecuador, England, Guatemala, Greece, Honduras, India, Italy, Japan, Madagascar, Malaysia, Mexico, The Netherlands, Nicaragua, Peru, Philippines, Republic of Seychelles, Scotland, Spain, Sri Lanka, Switzerland, Taiwan, Turkey, Uruguay, and Venezuela. In addition to the 79 oral, 2 video, and 120 poster presentations, 3 workshops were offered: Selina Heppell (Duke University Marine Laboratory) provided “Population Modeling,” Mike Walsh and Sam Dover (Sea World-Orlando) conducted “Marine Turtle Veterinary Medicine” and “Conservation on Nesting Beaches” was offered by Blair Witherington and David Arnold (Florida Department of Environmental Protection). On the first evening, P.C.H. Pritchard delivered a thoughtful retrospect on Archie Carr that showed many sides of a complex man who studied and wrote about sea turtles. It was a presentation that none of us will forget. The members considered a number of resolutions at the Thursday business meeting and passed six. Five of these resolutions are presented in the Commentaries and Reviews section of Chelonian Conservation and Biology 2(3):442-444 (1997). The symposium was fortunate to have many fine presentations competing for the Archie Carr Best Student Presentations awards. The best oral presentation award went to Amanda Southwood (University of British Columbia) for “Heart rates and dive behavior of the leatherback sea turtle during the internesting interval.” The two runners-up were Richard Reina (Australian National University) for “Regulation of salt gland activity in Chelonia mydas” and Singo Minamikawa (Kyoto University) for “The influence that artificial specific gravity change gives to diving behavior of loggerhead turtles”. The winner of this year’s best poster competition was Mark Roberts (University of South Florida) for his poster entitled “Global population structure of green sea Turtles (Chelonia mydas) using microsatellite analysis of male mediated gene flow.” The two runners-up were Larisa Avens (University of North Carolina-Chapel Hill) for “Equilibrium responses to rotational displacements by hatchling sea turtles: maintaining a migratory heading in a turbulent ocean” and Annette Broderick (University of Glasgow) for “Female size, not length, is a correlate of reproductive output.” The symposium was very fortunate to receive a matching monetary and subscription gift from Anders J. G. Rhodin of the Chelonian Research Foundation. These enabled us to more adequately reward the fine work of students. The winners of the best paper and best poster awards received $400 plus a subscription to Chelonian Conservation and Biology. Each runner up received $100. The symposium owes a great debt to countless volunteers who helped make the meeting a success. Those volunteers include: Jamie Serino, Alan Bolton, and Karen Bjorndal, along with the UF students provided audio visual help, John Keinath chaired the student awards committee, Mike Salmon chaired the Program Commiteee, Sheryan Epperly and Joanne Braun compiled the Proceedings, Edwin Drane served as treasurer and provided much logistical help, Jane Provancha coordinated volunteers, Thelma Richardson conducted registration, Vicki Wiese coordinated food and beverage services, Jamie Serino and Erik Marin coordinated entertainment, Kenneth Dodd oversaw student travel awards, Traci Guynup, Tina Brown, Jerris Foote, Dan Hamilton, Richie Moretti, and Vicki Wiese served on the time and place committee, Blair Witherington created the trivia quiz, Tom McFarland donated the symposium logo, Deborah Crouse chaired the resolutions committee, Pamela Plotkin chaired the nominations committee, Sally Krebs, Susan Schenk, and Larry Wood conducted the silent auction, and Beverly and Tom McFarland coordinated all 26 vendors. Many individuals from outside the United States were able to attend the 17th Annual Sea Turtle Symposium thanks to the tireless work of Karen Eckert, Marydele Donnelly, and Jack Frazier in soliciting travel assistance for a number of international participants. We are indebted to those donating money to the internationals’ housing fund (Flo Vetter Memorial Fund, Marinelife Center of Juno Beach, Roger Mellgren, and Jane Provancha). We raise much of our money for international travel from the auction; thanks go to auctioneer Bob Shoop, who kept our auction fastpaced and entertaining, and made sure the bidding was high. The Annual Sea Turtle Symposium is unequaled in its emphasis on international participation. Through international participation we all learn a great deal more about the biology of sea turtles and the conservation issues that sea turtles face in distant waters. Additionally, those attending the symposium come away with a tremendous wealth of knowledge, professional contacts, and new friendships. The Annual Sea Turtle Symposium is a meeting in which pretenses are dropped, good science is presented, and friendly, open communication is the rule. The camaraderie that typifies these meetings ultimately translates into understanding and cooperation. These aspects, combined, have gone and will go a long way toward helping to protect marine turtles and toward aiding their recovery on a global scale. (PDF contains 342 pages)

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Didemnum sp. A is a colonial ascidian or “sea squirt” of unknown geographic origin. Colonies of Didemnum sp. A were first documented in U.S. waters in 1993 at Damariscotta River, Maine and San Francisco Bay, California. An alarming number of colonies have since been found at several locations in New England and along the West Coast of the contiguous continental United States. Originally believed to be restricted to artificial structures in nearshore habitats, such as ports and marinas, colonies of Didemnum sp. A have also been discovered on a gravel-pavement habitat on Georges Bank at depths of 40-65m. The wide distribution of Didemnum sp. A, the presence of colonies on an important offshore fishing ground, and the negative economic impacts that other species of noninidigenous ascidians have had on aquaculture operations have raised concerns about the potential impacts of Didemnum sp. A. We reviewed the available information on the biology and ecology of Didemnum sp. A and potentially closely related species to examine the environmental and socioeconomic factors that may have influenced the introduction, establishment and spread of Didemnum sp. A in U.S. waters, the potential impacts of this colonial ascidian on other organisms, aquaculture, and marine fisheries, and the possibility that it will spread to other U.S. waters. In addition, we present and discuss potential management objectives for minimizing the impacts and spread of Didemnum sp. A. Concern over the potential for Didemnum sp. A to become invasive stems from ecological traits that it shares with other invasive species, including the ability to overgrow benthic organisms, high reproductive and population growth rates, ability to spread by colony fragmentation, tolerance to a wide range of environmental conditions, apparent scarcity of predators, and the ability to survive in human dominated habitats. At relatively small spatial scales, species of Didemnum and other nonindigenous ascidians have been shown to alter the abundance and composition of benthic assemblages. In addition, the Canadian aquaculture industry has reported that heavy infestations of nonindigenous ascidians result in increased handling and processing costs. Offshore fisheries may also suffer where high densities of Didemnum sp. A may alter the access of commercially important fish species to critical spawning grounds, prey items, and refugia. Because colonial ascidian larvae remain viable for only 12–24hrs, the introduction and spread of Didemnum sp. A across large distances is thought to be predominantly human mediated; hull fouling, aquaculture, and ballast water. Recent studies suggest that colony growth rates decline when temperatures exceed 21 ºC for 7 consecutive days. Similarly, water temperatures above 8 to 10 ºC are necessary for colony growth; however, colonies can survive extended periods of time below this temperature threshold as an unidentified overwintering form. A qualitative analysis of monthly mean nearshore water temperatures suggest that new colonies of Didemnum will continue to be found in the Northeast U.S., California Current, and Gulf of Alaska LMEs. In contrast, water temperatures become less favorable for colony establishment in subarctic, subtropical, and tropical areas to the north and south of Didemnum’s current distribution in cool temperate habitats. We recommend that the Aquatic Nuisance Species Task Force serve as the central management authority to coordinate State and Federal management activities. Five objectives for a Didemnum sp. A management and control program focusing on preventing the spread of Didemnum sp. A to new areas and limiting the impacts of existing populations are discussed. Given the difficulty of eradicating large populations of Didemnum sp. A, developing strategies for limiting the access of Didemnum sp. A to transport vectors and locating newly established colonies are emphasized. (PDF contains 70 pages)

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This report offers guidelines for the provision of adequate port reception facilities for vessel-generated garbage under the requirements of Annex V of the International Convention for the Prevention of Pollution From Ships, 1973 (MARPOL 73/78), Regulations for the Prevention of Pollution by Garbage from Ships. MARPOL Annex V prohibits at-sea disposal of plastic materials from vessels, and specifies the distance from shore at which other materials may be dumped. Annex V also requires the provision of port reception facilities for garbage, but it does not specify these facilities or how they are to be provided. Since the at-sea dumping restrictions apply to all vessels, the reception facility requirement applies to all ports, terminals, and marinas that serve vessels. These guidelines were prepared to assist port owners and operators in meeting their obligation to provide adequate reception facilities for garbage. The report synthesizes available information and draws upon experience from the first years ofimplementation of MARPOL Annex V. (PDF file contains 55 pages.)

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Este trabajo trata el estudio biológico del lago Pellegrini y las características limnológicas del ambiente desde el punto de vista pesquero y turístico en el lapso 1980-1998. Se realizaron monitoreos quincenales de calidad de agua y mensuales de plancton, plaguicidas, bacteriológicos, etc. en estaciones de muestreo situadas en el lago propiamente dicho, en el afluente y alrededores. Se analizan los problemas de eutrofización presentes, en la búsqueda de ensayos que disminuyan el deterioro del ecosistema. Los resultados comprueban un proceso de eutrofización natural, agravado por la actividad humana, con florecimientos de algas cianobacterias (Géneros Microcystis y Anabaena) y una disminución de la productividad secundaria y en la población íctica.

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ENGLISH: Near surface nutrient distributions in the eastern tropical Pacific Ocean, using data from the EASTROPAC Expedition of 1967-68 and pre~EASTROPAC data, are described. Nutrient concentrations were maximal along the equator, in the Peru Current and its offshore extension, and in the Costa Rica Dome and westward tensions of this feature. Nutrient-poor water was found north of the equator well offshore. In this water nitrate was often undetectable (<0.1 µg-at/liter) at the surface, but phosphate and silicic acid concentrations were moderate. Enrichment experiments showed that nitrogen was the primary limiting nutrient in poor water even though large amounts of organic N were found. Half saturation constants (K s ) were determined for ammonium-supported phytoplankton growth. These data were used to calculate near-surface primary productivity values which compared favorably with 14C values. Assimilation ratio measurements indicated that algae were not extremely nitrogen-deficient. Laboratory-determined K, values for phosphate and silicic acid indicated that these nutrients were rarely limiting. In rich water, chlorophyll levels were less than expected from nutrient levels, and this anomaly may be related to limitation by nutrients other than nitrogen (N), phosphorus (P), or silicon (Si), or to grazing. SPANISH: Se describe la distribución subsuperficial de los nutrientes en el Océano Pacífico oriental tropical, empleando los datos de la Expedición EASTROPAC de 1967~68 y datos anteriores a éstos. La concentración de nutrientes fue máxima a lo largo del ecuador, en la Corriente del Perú, en su prolongación mar afuera, en el Domo de Costa Rica y en las prolongaciones occidentales de esta característica. Se encontraron aguas pobres en nutrientes al norte del ecuador y bastante mar adentro. En estas aguas el nitrato era casi imperceptible (<0.1 µg-at/litro) en la superficie, pero las concentraciones de fosfato y ácido silícico fueron moderadas. Los experimentos de enriquecimiento indicaron que el nitrógeno era el principal nutriente limitante en aguas pobres, aun cuando se encontraron grandes cantidades de nitrógeno orgánico. Se determinaron las constantes de saturación media (K s ) para el desarrollo del fitoplancton sostenido por el amonio. Estos datos se emplearon para calcular los valores de la productividad primaria cerca a la superficie que pueden compararse favorablemente con los valores del 14C. Las medidas de la proporción de asimilación indican que las algas no tenían una deficiencia extremada de nitrógeno. Los valores determinados en el laboratorio de K, para el fosfato y ácido silícico indicaron que estos nutrientes limitaron rara vez la producción. En aguas ricas, los niveles de clorofila fueron inferiores a lo esperado según los niveles nutritivos y esta anomalía puede relacionarse a la alimentación o a la escasez de otros nutrientes distintos al nitrógeno (N), fósforo (P) o silicio (Si).