Repositório RCAAP

The diatom Cyclotella caspia Grunow, isolated from surface waters of the Ubatuba region (São Paulo State, Brazil) was submitted to different light spectral distributions for examination of its adaptative response. Growth rate and the photosynthetic pigments chlorophyll a, chlorophyll c, carotenoids and phaeopigments were measured under white, blue and red light of the same intensity (8 and 20 µE.cm-2.s-1). Growth rate increased under blue light while red light increased chl a concentration. The relative proportion of chl a and carotenoids did not change, demonstrating the absence of complementary chromatic adaptation.

P. tricornutum was grown in batch cultures under 21ºC temperature and continuous irradiance of 183 µE.m-2 . s-1, provided by fluorescent light tubes. Cultures growth were followed by cell countings, "in vivo" fluorescence and cellular protein, carbohydrate and chlorophyll-α content. The maximum value of protein/carbohydrate ratio was found at the exponential phase and the minimum value at the stationary phase. This ratio characterizes the physiological stage of the culture. Cell uptake rates for nitrate, ammonium and phosphate from the media were higher during the lag-phase. Nitrite excretion by the cells were detected following nitrate uptake.

Ascidians coloniais são muito comuns nas comunidades incrustantes crípticas no Canal de São Sebastião, São Paulo, Brasil. Elas colonizam, com sucesso, substratos artificiais tão logo estes são imersos. Neste trabalho, placas de cerâmica de 225 cm² foram utilizadas como substrato para o estudo do recrutamento e do processo inicial de sucessão de ascidias coloniais. Os resultados apresentados referem-se às cinco espécies mais abundantes e freqüentes. Diplosoma listerianum caracterizou-se como uma espécie inicial de sucessão, dominando as placas durante os primeiros dois meses. Trata-se de uma espécie oportunista, com reprodução contínua ao longo do ano, alta taxa de crescimento e ciclo devida curto. Symplegna brakenhielmi também apresentou maiores procentagens de cobertura durante o início da sucessão. Didemnum speciosum foi a espécie mais abundante logo após a imersão das placas, mas devido a uma taxa de crescimento mais lenta, somente após alguns meses é que esta espécie passou a dominar o espaço sobre as placas. Clavelina oblonga caracterizou-se como uma espécie tardia típica, com recrutamento pouco intenso, crescimento vertical e a presença de estruturas de proteção como, por exemplo, uma túnica grossa e resistente. Botryltus niger foi uma espécie menos abundante que desaparecia freqüentemente de todas as placas, reaparecendo geralmente através de recrutamento sobre outras espécies. Recobrimento de uma espécie pela outra não foi um tipo de interação freqüente entre ascidias durante a sucessão e parece mais provável que a substituição de espécies tenha ocorrido em função da morte dos indivíduos que colonizaram primeiro e que pertenciam a espécies de ciclo de vida curto. O espaço, que desta forma se tornava disponível, era ocupado pelo crescimento de espécies mais persistentes que haviam garantido sua presença sobre as placas através de recrutamento e da alta sobrevivência das jovens colonias.

An incubator is described which automatically simulates fluctuations of natural irradiance by coupling a photocell to a lightbank in the ship's laboratory. Design details are given.

No summary/description provided

As part of upwelling ecosystem project of the Cabo Frio region, 653 female of E. longimanus were obtained by monthly sampling from November 1986 to October 1988. Histological analyses were done in order to verify the type of spawning. Mean size at first spawning and the spawning season was determined The results indicate that mean size at first maturation is 75 mm standard length and all females were ready for reproduction at 95 mm Multiple spawning for the species was estimated, occurring from end of spring until the beginning of Fall, with peak spawning summer at water temperature between 13.2 and 18.7ºC (upwelling period in the region).

Diel vertical migrations of the marine dinoflagellate A excavatum were followed in a laboratory water column, and the effects of temperature stratification and nitrogen depletion on patterns of migration were examined. It was found that A. excavatum is a vertical migrator aggregating at surface during daylight, and descending at night. A six-degree thermocline did not restrict its migration but delayed the vertical movements. Nitrogen depletion in the culture was correlated with earlier downward migration in the day, and nitrate assimilation in the dark was confirmed. In another essay, with a nitrogen deficient culture, nocturnal nitrate uptake per cell was measured. It is suggested that the ability of A. excavatum to take up nitrate in the dark working together with diurnal vertical migration could be important mechanisms regulating bloom developments.

Parâmetros ambientais que influenciam a distribuição de populações do meiobentos litorâneo foram estudados em uma praia arenosa moderadamente exposta, localizada na Ilha Anchieta (23º32'S - 45º04'W), Brasil. Areias média a grossa, probremente selecionadas, com valores baixos de porosidade, teor de água e saturação ocorreram principalmente na porção superior da praia, de declive acentuado. Areias muito finas, bem selecionadas, com os mais altos valores de porosidade, teor de água e saturação, e menor teor de matéria orgânica, estiveram na porção inferior da praia, de declive suave. Os domínios refletivo e dissipativo puderam ser reconhecidos. No primeiro os sedimentos, mais grosseiros, podem ser, em parte, relictuais; os poros, mais amplos, são adequados à vida intersticial; o hidrodinamismo, mais brando, provavelmente condiciona maior estabilidade relativa e maior isolamento do sistema marinho adjacente. Neste domínio, as temperaturas do estrato superficial do sedimento podem alcançar valores altos. O domínio dissipativo, aqui só parcialmente amostrado, tem areias finas bem selecionadas sujeitas a forças hidrodinámicas mais vigorosas; as temperaturas tendem a apresentar valores menos extremos e mais uniformes.

Durante o período de outubro de 1985 a julho de 1987, foram coletados 722 ofíuróides pertencentes às espécies Ophioderma januarii e Ophioplocus januarii, na costa do Estado de São Paulo. Realizou-se medidas do diâmetro do disco dos exemplares e estas variaram entre 10,5 e 21,5 mm para Ophioderma januarii e entre 2,6 e 21,5 mm, para Ophioplocus januarii. Foram efetuadas observações das características morfológicas externas dos indivíduos e posteriormente, organizadas séries de crescimento, com o intuito de evidenciar possíveis alterações. Verificou-se para Ophioderma januarii, variações na forma dos escudos, no número de papilas orais e de espinhos braquiais, na coloração da superfície dorsal do disco e das placas braquiais dorsais e para Ophioplocus januarii variações nas escamas primárias, na série de escamas maiores da região interradial dorsal do disco, no número de escamas entre a centro-dorsal e a margem do disco, na forma dos escudos radiais e orais, no número de papilas orais, na coloração da superfície dorsal do disco e das placas braquiais dorsais. O resultado das análises de parâmetros ambientais dos locais de coleta, mostrou que as duas espécies ocorreram em áreas com condições ambientais distintas. Ophioderma januarii foi amostrada na região costeira até 36 m de profundidade e Ophioplocus januarii entre 30 e 100 m.

No presente trabalho estudaram-se a distribuição e a abundância de larvas de peixes da família Carangidae da costa sudeste do Brasil, entre Cabo Frio (23ºS) e Cabo de Santa Marta Grande (29ºS). As amostras foram coletadas com rede Bongô (malhagens de 0,505 mm e 0,333mm) em arrastos oblíquos, durante dez cruzeiros oceanográficos com o N/Oc. "Prof.W.Besnard", do Instituto Oceanográfico da USP e com N/Oc. "Cruz dei Sur", da PDP-SUDEPE. Foram identificados cinco táxons ao nível de espécie (Trachurus lathami, Chloroscombrus chrysurus, Decapterus punctatus, Selene setapinnis e Selene vomer), além de quatro ao nível de gênero (Oligoplites, Caranx, Serioia e Trachinotus). A espécie mais abundante foi T lathami (58,44% do total de larvas da família Carangidae), seguida por C. chrysurus (15,22%) e D. punctatus (12,17%). T. lathami e D. punctatus apresentaram distribuição ampla por toda a região nerítica, enquanto que C. chrysurus restringiu-se apenas às regiões mais próximas da costa. As larvas de carangídeos foram encontradas durante todas as épocas do ano, mas na primavera e no verão observou-se a maior abundância, o que caracteriza maior intensidade de desova durante estas estações. Esse período de pico de desova relaciona-se, aparentemente, à variação da estrutura hidrográfica da região.

Stomach contents of seven cartilaginous fish species were analysed with the aim to detect trophic groups. Sampling was effectuated between October/85 and July/87 off the coast of Ubatuba (São Paulo, Brazil) in waters up 50 m depth. The relative importance of different components of the diet was expressed as a percentage frequency of occurrence and percentage number. The seven species were grouped in: fish feeders - Squalus cubensis; benthonic crustacean and fish feeders - Raja castelnaui, Raja cyclophora, Raja agassizi; benthonic invertebrate feeders - Rhinobatos horkelii, Zapteryx brevirostris, Psammobatis glansdissimilis.

Cathorops sp has the diploid number of 54 chromosomes. The karyotype comprises lm + sm, 6m, 6sm and 14st pairs. This result is compared with those of other species of Ariidae, mainly Ariopsis felis and Arius dussumieri, found in literature.

The diet of Sagitta friderici off Ubatuba region, São Paulo State, was studied in March, 1989. Specimens were collected with a closing-net during three days at six hours' intervals (00:00; 06:00; 12:00; 18:00 h), at a fixed station of 38 m depth. The population was composed basically by young stages (O-II). A total of 3175 specimens were examined but only 760 contained preys in their guts. Copepods were the main constituent of food eaten (79.86%). There was a preference for the genera Paracalanus, Oncaea, Corycaeus and for crustacean nauplii. Other zooplanktonic groups such as Annelida, Urochordatha, and Mollusca were also found in the gut. Cannibalistic behavior occurred in 2.66% of the samples. In S. friderici the food was selected by size and was a direct function of the predator size. Younger stages (O-I) selected small prey, whereas older stages (II) preferred larger preys. Specimens collected above the thermocline exhibited higher feeding intensity (FCR) during the night periods.

The Brazilian sardine (Sardinella brasiliensis) and anchoita (Engrautis anchoita) inhabit the southeastern Brazilian Bight. The former spawns at night (21:00-03:00) in coastal region during late-spring and summer, meanwhile, the latter spawns all year-around, mainly in coastal region during summer and in neritic region during winter. The spawning time of E. anchoita was observed all day long, but more intensively at night. During summer there occurs a strong vertical stratification of water masses. The spawning of S. brasiliensis occurs in surface mixed layer, while that of E. anchoita occurs beneath the thermocline inside the cool South Atlantic Central Water which occupies the bottom layer during late spring and summer. However, the sardine and anchovy egss and larvae were found inside both the upper tropical and lower cold water masses, but predominantly above thermocline in this region

The inner continental shelf in front of the Massambaba beach, an East-West striking, 48 km long, double barrier beach, located between the towns of Saquarema and Arraial do Cabo presents a monotonous topography with only few outcrops of crystaline rocks, patches of beach rocks and a sediment cover of mainly relict quartz sand. The topographic gradient, steeper as expected for a passive shelf, reaches the 60 m isobath at a distance of about 4 nautical miles from the shoreline. A large outcrop of beach rock occurs at depths between 48 to 60 m, corresponding to the position of the shoreline of possibly 10,000 years ago. A small outcrop, near the profile S-4, at a depth of 4 m and distant 50 m from the beachface, is a good indication of shoreline retreat. The pattern of grain size shows a decreasing gradient both toward the East as also toward deeper waters. Input of continental sediments to the shelf is almost absent. Consequently the pattern of sediment distribution must primarily be due to the introduction of sediments trough an ancient Pleistocene drainage system, interrupted by the construction of a barrier beach, and to the reworking of sediments due to waves and currents. The interpretation of existing current measurements, as also of the grain size distribution parameters, indicate that net sediment movement is directed to the East.

Between June 1982 and February 1983 a survey of the marine molluscs of the Channel of São Sebastião, State of São Paulo, was carried out A total of 195 species were found: 103 gastropods, 87 bivalves, 4 chitons, and 1 scaphopod. 140 species belong to the Caribbean fauna, 22 are circumtropical or worldwide in distribution, 13 are endemic to the Brazilian coast, and 10 belong to the Patagonian fauna. Most species (77,6 %) were found in the intertidal zone. 142 species, recorded for the region by other authors and not found in the present survey, are also listed. A reduction in the number of species was also observed comparing the present data (1982-1983) with more recent data from other authors (1987-1989). This situation is probably due to chronic pollution and other environmental impacts.

A survey for bivalves (Teredinidae) at several sites in the Escuro River and Comprido River at mangrove regions in Praia Dura , Ubatuba, SP was conducted. Nausitora fusticula was the most abundant species found in all collection sites at the border of Comprido River meaning that the species was well adapted to the intertidal regions and to the large variation in salinity (0 to 33 S). N. fusticula was found with Bankiafimbriatula, Bankiagouldi and Bankia rochi at the mangrove region in contact with the water. At the regions less influenced by the tides N. fusticula occurred with Neoteredo reynei and few specimens of the genus Banida already cited. The species of Teredinidae was found at the maximum limit of penetration of the sea water during the high tides. When the salinity was lower neither Banida species nor Neoteredo reynei occurred, but Psiloteredo healdi and AC fusticula were found.

The aim of this study was to establish the importance of the macrofauna as food for young fish species that inhabit the infralittoral adjacent to the lower marsh. The sampling site is located at Arrozal, Cananéia lagoon estuarine region (25º02'S and 47º56'W) and the collectings were realized monthly, during a year. The results suggest that the studied area could be considered as a nursery ground for young fish species. The local macrofauna is composed mainly by several groups of crustaceans and has a marked temporal variation. Mysids were dominant in Spring, copepods in Summer, mysids and bivalves were co-dominants in the Autumn and amphipods in Winter. Mysids, copepods, ostracods, tan aids and other epifaunal crustaceans were more consumed than other items. According to the trophic habits, the twelve fish species could be divided into three groups: the first and the third as mysids and copepods eaters respectively, and the second group with a balanced diet reflecting more than the other groups the seasonal variation of the macrofauna collected by the dredge. Benthonic and benthopelagic organisms were considered the major food source, being consumed by 75% of the analysed fish species, in Cananéia infralittoral.

Samples of Antarctic krill, Euphausia superba, collected from 18 locations in the Drake Passage, Bransfield Strait and on the west coast of the Antarctic Peninsula were analyzed for protein variation using enzyme electrophoresis. Of 19 enzyme loci studied, 14 (73,6%) exhibit allelic variations. Average heterozigosity for a station varies from 0,129 to 0,157. Five loci are with null alleles. Differences in allelic frequency related to sex and size of animal were not observed. No significant deviations from random mating expectation according to the Hardy-Weinberg principle were found in any locus at any station except Aph-1 at the stations 8 and 18; Est-1 at the station 9 and 11, and Mdh-1 at the station 18. These deviations are likely due to the difficulty in .analysing the enzyme pattern or to the small sample sizes. Analysis of allele distribution indicate that samples from all locations are homogeneous in all polymorphic loci. Genetic distances between samples vary from 0.000 to 0.002. These results suggest that specimens from all locations of the investigated region belong to a single genetically homogeneous population. The contribution of physical and biological factors to the homogeneity of krill in the region and the necessity of a detailed study utilizing not only electrophoresis but also another techniques were discussed.

Density and diversity patterns of the polychaetous annelids from the northern continental shelf of São Paulo State, Brazil, were studied. Polychaetous densities were higher in the inner shelf, mainly in the southern transect. Temporal variations were observed at the northern and central transects in the 20 and 35 m isobaths, with higher summer values. Diversity values were lower in summer and higher during winter in the outer shelf. The inner shelf presented more complex diversity patterns with seasonal fluctuations in lower depths. Muddy sediments presented higher densities; diversity and richness were higher in fine sand sediments. Coarser sediments presented the highest values of evenness but low diversity. The higher diversity values in the shallowest stations were due to the higher number of species and in the deepest stations to the great evenness.