86 resultados para Brasil - Indústrias - 1972-1976


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Results are given of monthly net phytoplankton and zooplankton sampling from a 10 m depth in shelf, slope, and Gulf Stream eddy water along a transect running southeastward from Ambrose Light, New York, in 1976, 1977, and early 1978. Plankton abundance and temperature at 10 m and sea surface salinity at each station are listed. The effects of atmospheric forcing and Gulf Stream eddies on plankton distribution and abundance arc discussed. The frequency of Gulf Stream eddy passage through the New York Bight corresponded with the frequency of tropical-subtropical net phytoplankton in the samples. Gulf Stream eddies injected tropical-subtropical zooplankton onto the shelf and removed shelfwater and its entrained zooplankton. Wind-induced offshore Ekman transport corresponded generally with the unusual timing of two net phytoplankton maxima. Midsummer net phytoplankton maxima were recorded following the passage of Hurricane Belle (August 1976) and a cold front (July 1977). Tropical-subtropical zooplankton which had been injected onto the outer shelf by Gulf Stream eddies were moved to the inner shelf by a wind-induced current moving up the Hudson Shelf Valley. (PDF file contains 47 pages.)

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ENGLISH: Beginning in February 1972 the usual seasonal cooling of the surface water of the eastern Pacific Ocean in the region of the Peru Current and along the equator failed to develop. By July tropical coastal and equatorial island stations and ships crossing the equator were recording sea-surface temperatures which were 6° to 8°F (3.3°-4.4°C) above the long-term mean. The anomalies spread over most of the eastern tropical Pacific and westward into the central equatorial Pacific through September. During October surface temperatures at coastal stations along South America were returning to normal, but in November and December 1972 temperatures rose rapidly again, with a near-record temperature anomaly of 8.1°F (4.2°C) above the long-term mean recorded at Puerto Chieama, Peru (7°42'S-79°27'W). After January 1973 sea-surface temperatures began returning to normal over most of the eastern tropical Pacific, and by March 1973 the El Nino had completed its cycle. Monthly sea-surface temperature anomalies over the eastern tropical Pacific are discussed to show the extent and magnitude of warming. Annual temperature profiles at several South American coastal and equatorial island stations are compared with temperature profiles for the 1957-1958 and 1965 EI Nino years. Characteristics of the temperature anomaly profiles at Puerto Chicama during several very warm years for the 1925-1972 period are also compared. Finally, meteorological factors contributing to a relaxation of the southeast trade winds and to the decreased unwilling along the coast of South America in 1972-1973 are examined. SPANISH: A comienzos de febrero de 1972, no se registró el enfriamiento común estacional del agua superficial del Océano Pacífico oriental en la región de la Corriente del Perú y a lo largo del ecuador. En julio las estaciones tropicales, costeras y de las islas ecuatoriales, y los barcos que cruzaban la linea ecuatorial registraron temperaturas superficiales del mar de 6° a 8°F (3.3°-4.4°C) más altas que la media a largo plazo. Las anomalías se esparcieron sobre la mayoría del Pacífico oriental tropical, y al oeste en el Pacífico central ecuatorial. En octubre, las temperaturas superficiales de las estaciones costaneras a lo largo de Sudamérica volvieron a la normalidad, pero en noviembre y diciembre de 1972, las temperaturas de nuevo ascendieron rápidamente con una anomalía de temperatura que alcanzó 8.1°F (4.2°C) sobre la media a largo plazo registrada en Puerto Chicama, Perú (7°42'S-79°27'W). Después de enero 1973 las temperaturas de la superficie del mar volvieron rápidamente a la normalidad en la mayoría del Pacífico oriental tropical y en marzo de 1973 el Niño había completado su ciclo. Se discuten las anomalías mensuales de las temperaturas de la superficie del mar en el Pacífico oriental tropical para indicar la extensión y magnitud del calentamiento. Los perfiles anuales de temperatura en varias estaciones costeras y de las islas ecuatoriales sudamericanas se comparan con los perfiles de temperatura de los años en que ocurrió el Niño en 1957-1958 y 1965. Se comparan también las características de los perfiles de las anomalías de temperatura en Puerto Chicama durante varios años muy cálidos para el período de 1925-1972. Finalmente, se examinan los factores meteorológicos que contribuyen al debilitamiento de los vientos alisios del sudeste y a la reducción del afloramiento a lo largo de la costa sudamericana en 1972-1973. (PDF contains 48 pages.)

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About 86 species of fish have been recorded in the Lake Chad. Most of the species occurring in the lake are widespread including most of the commercially important species. Fish distribution in the lake was adversely affected by the 1972/73 and 1983/84 droughts. The commercially important species before the 1972/73 drought were; Lates, Labeo distichodus, Heterotis, Gymnarchus, Hydrocynus, Citharinus and Bagrus. Other species which had less commercial value at that time include, Clarias, Gnathanemus, Polypterus, Protopterus, Tilapia and Synodontis. Lates niloticus was the most predominant species of commercial importance comprising 50-60% of the total catches of fishermen between 1962 and 1973. Before the 1972/73 drought, occurrence of Clarias lazera was negligible and restricted to long line catches and had little commercial value. As a result of the drought of 1972/73 which resulted in near drying up to the northern sector of the lake, fish populations were confined to isolated pools and were completely scooped out. The remaining fish populations retreated to the southern basin where enough water always remained to hold the surviving representatives of the population. The effects of the drought resulted in occurrence of the little known C. lazera along with other hardy species like Tilapia and Protopterus to dominate the existing fish species composition. In 1976, C. lazera dominated the total catches of fishermen with 85.6%. An overview of the fish population in the lake, their relative abundance, changes in species composition, the effects of drought on the fauna of the lake based on the available data are discussed in this paper

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Examination of 40 time series of multidisciplinary environmental variables from the Pacific Ocean and the Americas, collected in 1968 to 1984, demonstrated the remarkable consistency of a major climate-related, step-like change in 1976. To combine the 40 variables (e.g., air and water temperatures, Southern Oscillation, chlorophyll, geese, salmon, crabs, glaciers, atmospheric dust, coral, carbon dioxide, winds, ice cover, Bering Strait transport) into a single time series, standard variants of individual annual values (subtracting the mean and dividing by a standard deviation) were averaged. Analysis of the resulting time series showed that the single step in 1976, separating the 1968-1975 period from the 1977-1984 period, accounted for 89% of variance within the composite time series. Apparently, one of the Earth's large ecosystems occasionally undergoes large abrupt shifts.

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The reaction of Mn(II) with water-dissolved oxygen, to a higher manganese hydroxide in an alkaline medium, as with the longstanding classic Winkler method, is the first step in the method described here. The assumption for faultless results by the conventional and modified Winkler method is clean water, which contains no organic substances by Mn(III) or Mn(IV). In many cases, however, eg. in river and lake-water tests, it can be seen with the naked eye that after some time the originally brown-coloured precipitate of manganese hydroxide becomes more and more colourless. Oxygen content was analysed in the water samples and evaluated by raising the amount of the leuko-base and giving the corresponding dilution of the colouring matter solution formed still higher oxygen contents can be measured.

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A modified method of the Biochemical oxygen demand (BOD)test was applied in order to find out the seasonal changing activity of the nitrifying bacteria in surface waters. Samples were taken from the River Elbe near Teufelsbrueck.

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Members of the family Gammaridae are very closely interrelated. There arises the question as to how far they also differ amongst themselves through physiological characteristics. Comparative respiratory and physiological experiments were made on the five euryhaline species Gammarus locusta, G. oceanicus, G. salinus, G. zaddachi and G. duebeni. The respiratory measurements carried out within the framework of this experiment were occupied with the relationships between oxygen consumption and body size depending on salinity. They also had the object of determing the variations in metabolic intensity after an abrupt change in the salt content of the external medium, and to establish the period of time for the process of adaptation. As the experiments were carried out polarographically in a testing plant with continuous flow-through, and the method which was applied permitted continuous recording over prolonged intervals, there could also be carried out comparisons between metabolism at rest and under activity, and the alterations of oxygen consumption during the process of moulting could be measured.

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By the industrial cultivation of blue-green algae, there very much appears the important question about their carbon nutrition. Spirulina grows within the range of pH value of medium of 8.5 - 11.0. In this range of pH value in the culture medium CO2 is present in the form of bicarbonate and carbonate, which serves as principal source of carbon for the present type of algae. There is little information yet about the influence of the pH of the medium, and the form of carbon components of the medium, on the rate-increase of Spirulina. Investigations were conducted into the influence of some pH values of medium on the rate-increase of the alga Spirulina platensis.

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Experiments were undertaken with the purpose to find out the tolerance of different species of salmon fish in acid hatching water and if different strains of the same species differ in their response. The study was made in the Fins-river hatchery, Marnardal and the assumption tested that the salmon and trout stock from Sorland are adapted to the more acid milieu, and thus more robust in acid water than are comparable fish stocks from areas where the water is only a bit acid or neutral.

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A description of the algal genus Cladophora from Vol 10 of the ”Freshwater Flora of Poland”. Illustrations are included.

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The Goggausee, a small, shallow, meromictic lake(700m long, 150m wide, max. depth=12m, mean depth=6m), was the site of a week long study (19-26 May 1974) of the limnology department of the University of Vienna. The study comprised pollen analysis and palaeolimnological studies on the one hand, as well as a stock- taking of physiochemical factors, primary production, bacteria, zooplankton, zoo benthos and fish on the other. This paper studies the zooplankton of the lake. The Goggausee is a meromictic lake, with its anoxic deep water, that restricts the vertical distribution of most zooplankton. The aim of the study was to pursue the vertical distribution of the rotifers and Crustacea. Density of individuals, biomass, percentages of zooplankton together and crustaceans and rotifers as groups. Special consideration is given to the the Dipteran Chaoborus flavicans.

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The river perch (Perca fluviatilis L.) is most active in the daytime hours, and displays seasonal changes of diel rhythm with a break of the rhythm in spring and autumn. In the present work data were obtained on the motor activity of 3 perch measuring l8-20 cm, caught by net in the littoral of a reservoir and spawned under laboratory conditions. The degree of intensity of movement of perch was judged by special experiments. The results are summarised in this short paper.

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Species of Pithophora occasionally appear in Europe and are associated mostly with the tropical, higher water plants, cultivated in numerous botanical gardens. In June 1973 pale green, branched threads were discovered in the pond of the Wroclaw Botanical Garden, amongst filaments of Spirogyra crassa (Kutz.) Czurda emend. and Cladophora glomerata (L.) Kutz. floating on the water surface. They were maintained for several weeks in crude cultures and produced numerous, dark akinetes tightly packed with reserve material. This collected material was found to be a member of the family Pithophora, Wittr. Further examinations identified the material as Pithophora oedogonia. The findings point out that it is probable, that species of Pithophora Wittr. can become acclimatized in Europe, primarily in ponds of botanical gardens, where consequently they are able to tangle easily with higher tropical plants.

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In a slow flow, on a smooth uniform substratum, a limited bed allows the existence of currents slow enough for benthic invertebrates. These conditions rarely occur naturally. The investigations carried out in this work aimed, on an intermediary scale, to define the influence of irregularities in the substratum on flow near the bottom. The substrata used were made of glass marbles. The investigations were carried out in a transparent channel of 70 cm in length and a rectangular section 10 x 5 cm. The data was analysed to study the general evolution of flow in terms of average speeds and the appearance of the turbulence near the bottom.

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The identification of fish zones in western and central Europe has been the objective some major studies. This paper concerns a stream in Normandy specially studied by the author in 1969 and 1970 in the framework of a study on the role of the mean temperature in fish zoning. The paper propounds the comparative study of the morphodynamic and occasionally physico-chemical characteristics, as well as the results of previous sampling by electric fishing of the fish populations of two other streams of the higher Cretaceous layer and supplied by ”chalky” water in Normandy and Picardy.