39 research outputs found

    Noticias y experiencias

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    La producción de la Universidad española en Física, reflejada en las publicaciones españolas y extranjeras

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    The scientific productíon of Spanish Universities in the field of Physics for the period 1986-88 is analyzed with data obtaincd from two databases: INSPEC, whích covcrs publications in foreign journals and also, but only in a selective way, those published in a certain numbcr of Spanísh journals; and ICYT, which covcrs comprehcnsively ali original papcrs published in Spanish journals. Comparison of the two series of data Ieads to ccrtain conclusions as rcgards the trends to publish in foreign journals. A further comparison is made betwcen the periods 1982-85 and 1986-88, with thc data obtained from INSPEC.Se analiza la producción científica de la Universidad española en el campo de la Física, y en el período 1986-88, a través de dos bases de datos: INSPEC, que recoge lo publicado en revistas extranjeras y también, aunque de modo selectivo, en cierto número de revistas españolas; e ICYT, que recoge exhaustivamente todos los trabajos originales publicados en revistas españolas. La comparación entre ambas series de datos permite deducir tendencias de publícación en el extranjero. Asimismo se analizan comparativamente los periodos 1982-85 y 1986-88, con los datos obtenidos de INSPEC

    Fisheries and Oceanography off Galicia, NW Spain: Mesoscale Spatial and Temporal Changes in Physical Processes and Resultant Patterns of Biological Productivity

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    The Galician shelf off NW Spain (43N degrees 9W degrees) exhibits mesoscale spatial and temporal changes in biological productivity associated with upwelling. Spatial heterogeneity results from local geomorphic and land-sea interactions superimposed on the large scale atmospheric processes that produce upwelling. Wind-induced upwelling events, commonly of short (i.e., week) duration, are more common in the summer than in the winter. A Series of cruises, including some time series sampling, and satellite imagery analysis showed that surface upwelling was more common and persistent on the northern coast compared with the western coast off the coastal embayments, the Rias Bajas. Nearshore off the rias, coastal runoff, which is greater in the rainy winter/spring versus the dry summer, affected upwelling. In early summer, upwelling less often reaches the surface because of increased water column stratification associated with lower surface salinities and thus upwelling is not detected by satellite imagery. Conversely, in late summer, upwelling more often reaches the surface because coastal runoff is reduced during the dry summer months and the water column tends to be less stratified. Plankton biomass and rate processes along the Galician shelf reflected both ambient hydrographic conditions as well as prior history of upwelling or downwelling. Phytoplankton and bacterioplankton were in greatest abundance during upwelling conditions (June through August); in contrast, both zooplankton and fish larvae exhibited highest abundances in March, when there were upwelling conditions prior to our cruise. Spatial differences in the duration and frequency of upwelling events, in combination with advection of water masses, are critical to the patterns of water column productivity and sardine fisheries production off the Galician coast. More persistent upwelling at this NW corner of the Iberian peninsula Supports large sardine fisheries because zooplankton and larval fish populations have time to respond to the higher primary production. Farther down the western Galician coast, the episodic upwelling and resultant intermittent primary production does not support a stable food supply needed to support fisheries. Times series sampling revealed mean response times of bacteria, phytoplankton, and zooplankton to be on the order of a day, days, and weeks, respectively. Sardines showed no spawning response in the relatively short time series sampling. The observed distributional patterns of fish eggs and larvae showed some offshore transport of fish larvae that were spawned inshore during upwelling periods and aggregation of larvae in a convergence zone northwest of Cabo Villano

    Enobrecimento, trajetórias sociais e remuneração de serviços no império português: a carreira de Gaspar de Sousa, governador geral do Estado do Brasil

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    Recent trends in plankton and upwelling intensity off Galicia (NW Spain)

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    The mean intensity of the NE Atlantic upwelling system at its northern limit (Galicia, NW Spain) decreased during the last 40 years. At the same time, warming of surface waters was detected. Plankton biomass and composition are expected to reflect such changes when integrated over large time and space scales. In this study, biomass, abundance and species composition of phyto- and zooplankton were analysed to search for significant patterns of annual change and relations with upwelling intensity. Regionally integrated, mostly offshore, data were obtained from the Continuous Plankton Recorder (since 1958) whereas coastal data from Vigo and A Coruña came from the Radiales program (since 1987). No significant trends were found in phytoplankton biomass at either regional or local scales. However, there was a significant decrease in diatom abundance at regional scales and also of large species at local scales. Zooplankton abundance (mainly copepods) significantly decreased offshore but increased near the coast. Biomass of zooplankton also increased near the coast, with the fastest rates in the south. Warm-water species, like Temora stylifera, were increasingly abundant at both regional and local scales. Significant correlations between upwelling intensity and plankton suggest that climatic effects were delayed for several years. Our results indicate that the effects of large scale climatic trends on plankton communities are being effectively modulated within the pelagic ecosystem in this upwelling region
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