Resumo em Inglês:
The seasonal and spacial distributions of dissolved oxygen, temperature and salinity of surface and bottom waters over the continental shelf south of Torres, southern Brazil, were investigated from April 1968 to March 1969. The maxima and minima values of oxygen concentration in the upper layers were observed during the winter and summer along the coast (10-35 nm), respectively. Near the bottom this characteristics changes reflecting the northward advection of low oxygen water along the coast. For the sections along the continental shelf covering distances up to 100 nautical miles, the association of high oxygen concentration with low temperatures and low oxygen concentration with higher temperatures was also observed for distances no longer than 60 ran. Further east and below the surface layer, this tendency is modified by the advection of oceanic water from tropical and subantarctic origin. Near the coast, the oxygen maxima (5.0 ml/l) is associated with salinity values ranging from 30 to 33‰ (temperature values between 12 and 15ºC), indicating that (its occurrence) is probably due to the fresh water run-off from La Plata River. Some results of the changes in the nutrient concentrations during 1972 are also described.Resumo em Inglês:
Seasonal differences in sigma-t (1.8)3 temperature (4.0ºC) and salinity (0.9‰) were observed during February/June 1976 in the vicinity of Ilha Grande off the coast of Brazil Estimates of static and dynamic stability were made through the calculation of Brunt-Vaisala frequencies and Richardson numbers, respectively. Both static and dynamic stability values were larger in February than in June for the same location and suggest a greater column stability in February than in June. Stations located in the northern and western channels of Ilha Grande, however, contained greater density reversals than to the east of the Island. Small scale dispersion studies were made using Rhomamine B dye to determine horizontal diffusion coefficients (K) east of the Island and in an embayment of the Island. The estimate for K was 9X10³ cm² s-1 east of the Island, about 2.6 times greater than the value estimated for the protected embayment.Resumo em Português:
Foram efetuadas várias medidas de excreção de matéria orgânica dissolvida (MOD), utilizando-se populações naturais de fitoplâncton, provenientes da Enseada do Flamengo - litoral Norte do Estado de São Paulo - e enriquecidas artificialmente com nutrientes. A quantidade absoluta da MOD excretada, de um modo geral, acompanhou a quantidade de carbono total assimilado. Entretanto, nas populações com deficiência de nitrogênio, ocorreu um aumento das taxas relativas de excreção, não só devido à diminuição da assimilação total de carbono, mas, efetivamente, tambem ao aumento da quantidade absoluta de MOD excretada.Resumo em Inglês:
Measurements of excreted dissolved organic matter (DOM) were carried out twice (in simmer and winter) using natural phytoplankton populations from "Enseada do Flamengo" (Lot. 23° 30'S-Long. 045°069'W) and enriched artificially with nutrients. The bioassays were carried out inoculating samples of an integral sea water in ten liters flasks, incubated "in situ". Measures were taken in populations growing in: integral " f " media, "f" - N, "f" - P, "f" - (H + P), "f" - (Vit. + Metal traces), and in a control without enrichment. The absolute amount of excreted DOM generally followed the quantity of total carbon assimilated. In the meantime, with the populations with nitrogen deficiency occurred an increase of relatives rates of excretion, not only due to the total carbon assimilation diminution, but effectively also to the absolute increase of the quantity of excreted DOM.Resumo em Inglês:
Some aspects of the procedures to measure dissolved organic matter (DOM) released by phytoplankton account for important sources of errors. These aspects include: cell damage upon filtration of samples, residual inorganic 14C in the filtrates, NaH14CO3 ampoule contaminations and the low radiation activity proper to the released samples. Some experiments on these procedural problems were carried out and their effects on the released DOM were evaluated. A procedure to use control samples to avoid errors in the technique of DOM analysis by the liquid cintillation counter is described. Experiments on the validity of stocking preserved filtrates of natural plankton populations and algal cultures were also carried out for long periods prior to the radioactivity measurements.Resumo em Inglês:
A series of experiments with natural phytoplccnkton populations was made to study the photosynthetic Pmax and a indices, under different phases of the diel cycles. By "in situ" and simulated experiments the exogenous and endogenous influences on the photosynthesis and total chlorophyll-a were studied. The results obtained indicate the diel variation can introduce a great deal of error in the determination of the primary production. The use of constant values for a and Pmax in the equation for the determination of primary production without carrying for the aspect above as well as for the seasonal variation may give results for the diurnal values, with a very lend accuracy and without ecological significance. It was also observed that the measurements of chlorophyll-a varied within the relatively short period of time, required to perform a determination of photosynthesis. It is suggested that the Pmax, a and Ik values used in primary productivity methodology should be revised, as the indices considered are based in chlorophyll concentration.Resumo em Espanhol:
El estúdio inicial de la fauna y distribución de cefalópodos de Brasil se convirtio en una revisión de la zoogeografía de la región Tropical-Subtropical del sur del Brasil. Observaciones iniciales sobre zoogeografía marina brasileña tuvieron lugar en la primera parte del siglo XIX por naturalistas franceses, principalmente d'Orbigny, trabajando en cefalópodos. Posteriormente, el primer patrón global de provincias zoologicas, definidas por James Dana en 1853 y basadas en zonas de temperaturas oceanicas, colocan el extremo meridional de la fauna tropical del Atlántico Occidental en una latitud de 30ºS, incluyendo una zona de transición (São Paulo) entre Rio de Janeiro y Porto Alegre. El análisis detallado de numerosos estúdios subsecuentes en esta región lleva a la confirmación de la validez conceptual de los puntos de vista de d'Orbigny, Dana, Forbes, Woodward y algunos mas durante el siglo pasado. En su tratado zoogeográfico de 1953, Ekman no tuvo a su disposición información adecuada sobre Brasil y señaló vagamente a Rio de Janeiro como el extremo sur de la fauna tropical, basado en la aparente ausencia de manglares y de arrecifes de coral. Este punto de vista ha sido fuente de confusión y debate, especialmente en el siglo XX. Toda la información oceanógrafica, geológica, sedimentaria y faunística acumulada y estudiada hasta el presente señala a la región entre Rio Grande do Sul y Rio de la Plata, como la barrera ecológica fundamental (principalmente debido a cambios de temperatura), en la distribución sur de organismos tropicales. Entre Espirito Santo y Rio Grande do Sul existe una zona de transición faunística caracterizada por complejas variaciones medioambientales estacionales, bajo la influencia alterna y combina de las Corrientes del Brasil y Falkland, en la margen occindetal de la Convergencia Subtropical/Subantartica. Esta zona de transición constituye una provincia biogeografica, designada "Paulista", que contiene una proporcion significativa de elementos endemicos y algunos miembros de las faunas adjacentes, Caribe y Patagónica, ademas de organismos circuntropicales. Los límites de la provincia Paulista se hallan, en el norte en la isoterma de los 23ºC, y en el sur, en la isocrima (temperaturas mas frías durante 30 días consecutivos, definidas por Dana, 1853) de los 23ºC.Resumo em Inglês:
The zoogeography of the Tropical/Subtropical region of Southern Brazil is reviewed through a detailed analysis of numerous studies by different authors. Transition zones are established in the global patterns of zoological provinces (Dana, 1853). The Province "Paulista" is proposed between the States of Espírito Santo and Rio Grande do Sul, limited north and south by the 23ºC isotherm.Resumo em Inglês:
The southern boundaries of Tozeuma serratum A. Milne Edwards, Salmoneus ortmanni (Rankin) and Processa profunda Manning & Chace, previously known only from the northwestern Atlantic, have been extended to São Paulo, Paraná and Uruguay, respectively. Latreutes parvulus (Stimpson), previously not known beyond São Paulo has been found to as far south as the Province of Buenos Aires. A systematic account of these four species is furnished, based mainly on material collected by the R/V "Prof. W. Besnard". The 16 species of Alpheoidea whose southern boundaries occur in warm-temperate shelf waters of eastern South America belong to two distinct faunal assemblages: (1) Tropical species - Alpheus floridanus Kingsley, A. intrinsecus Bate, A. normanni Kingsley, Salmoneus ortmanni (Rankin) Synalpheus longicarpus (Herrick), Ogyrides alphaerostris (Kingsley) (= O. occidentalis(Ortmann)), Exhippolysmata oplophoroides (Holthuis), Latreutes parvalus (Stimpson), Processa bermudensis (Rankin) and P. hemphilli Manning & Chace - which are largely restricted to coastal and inshore shelf waters less than 50 m deep; and (2) Subtropical species - Alpheus pouang Chris toffersen, A. puapeba Christoffersen, Merhippolyte americana Holthuis, Tozeuma serratum A. Milne Edwards, Processa guyanae. Holthuis and P. profunda Manning & Chace - which are largely restricted to the outer portion of the continental shelf within the studied area. Considering the temperature and distributional data available for each species, it is suggested that the poleward boundaries of O. alphaerostris are set by maximum summer temperatures of about 20ºC required for the reproduction of the species, while the poleward boundaries of most of the tropical and subtropical species are set by minimum winter temperatures critical for their survival: about 15ºC for A. floridanus, about 11ºC for E. oplophoroides, about 9ºC for A. pouang, L. parvulus, P. guyanae., P. guyanae and P. hemphilli, and P. profunda and about 8ºC for A. puapeba and M. americana. It is further suggested that the shoreward boundaries of some of the subtropical species are set by maximum summer temperatures critical for their survival: about 20-22ºC for A. puapzba and about 17-18ºC for A. pouang and M. americana.