Ecological studies in the bay of Paranaguá: I. horizontal distribution and seasonal dynamics of the phytoplankton

Five stations were sampled monthly in the Bay of Paranaguá during one year cycle (1983-1984) to measure basic environmental parameters, phytoplankton biomass and photosynthesis with the purpose of understanding the principal factors that regulate the phytoplankton growth and distribution throughout the year. Surface temperature varied from 17 to 30ºC. The yearly average values for salinity, dissolved oxygen and pH ranged from 9.38 to 32.00, 5.17 to 5.53 ml/l and 7.46 to 8.18, respectively. Average concentrations of total inorganic nitrogen, phosphate and silicate varied from 3.31 to 8.48, 0.38 to 0.97 and 27.68 to 98.36 µg-at/l, respectively, with increasing concentrations toward the inner bay. Chlorophyll-a at the surface varied between 2.86 and 13.99 mg/m³ with high concentrations in the inner bay associated with high nutrient contents and lower salinities. Low photosynthetic rates were measured at the surface, varying from 0.01 to 7.36 mgC/m³/h. Phytoflagellates and Skeletonema costatum dominated the phytoplankton population during the study period. The temporal fluctuations in the inner bay are associated with the rainfall regime. High amounts of precipitation increase the concentrations of nutrients and consequently improve the phytoplankton growth. This is however limited by nitrogen deficiency (as indicated by the low N to P ratios observed) and turbidity.Foram feitas coletas mensais na Baia de Paranaguá (Paraná) em 5 estações fixas durante um ano (1983-1984) para se medir parâmetros ambientais básicos, biomassa e fotossíntese do fitoplâncton durante um período sazonal. A temperatura na superfície variou de 17 a 30ºC. As médias anuais de salinidade, oxigênio dissolvido e pH variaram de 9,38-32,00, 5,17-5,53 ml/l e 7,468,18, respectivamente. As concentrações médias do nitrogênio inorgânico total, fosfato e silicato variaram de 3,31-8,48, 0,38-0,97 e 27,68-98,36 µg-at/l, respectivamente, com os máximos obtidos na parte mais interna da baia. A clorofila-a na superfície variou entre 2,86 e 13,99 mg/m³ com máximos na parte mais interna da baía associadas às altas concentrações de nutrientes e salinidades mais baixas. As taxas de fotossíntese obtidas na superfície variaram entre 0,01 e 7,36 mgC/m³/h, com máximos na região mais interna da baía. Fitoflagelados e Skeletonema costatum dominaram a populaçao fitoplanctonica durante o período estudado. As variações temporais no interior da baía foram associadas ao regime de chuvas. A alta pluviosidade aumenta a concentração de nutrientes e conseqüentemente, estimula o desenvolvimento do fitoplâncton que é, no entanto, limitado pela deficiência em nitrogênio e pela turbidez da água

Roland Barthes in Brazil, by translations

This article studies the reception to the work of Roland Barthes in Brazil through the translations of his books and essays. More specifically, and according to the Theory of Literary Polysystem, by Itamar Even-Zohar, it retraces the history of Barthes trans-lations in its relations with the most important Brazilian intellect-tual scenarios for his work, the 70’s and 2000’s: at first, the works of the French writer that best met the desire of Brazilian intellect-tuals for theories came from linguistic studies, versatile enough to serve as an analytical basis for the reading of the most varied objects; in a second moment, interest in Barthes found in the canonization imposed by the postmodernity thought the justifica-tion for a review of his work. Both in the first and the second moments, the translations of Barthesian texts reflect different images of the French writer, built by Brazilian intellectuals, which show the characteristics of each of these historic cultural mo-ments.Este artículo analiza la recepción de la obra de Roland Barthes en Brasil a través de las traducciones de sus libros y ensayos. Bajo la perspectiva de la Teoría literaria de los Polisistemas de Itamar Even-Zohar, este estudio reconstruye la historia de las traduccio-nes de Barthes relacionándolas con los más importantes escena-rios intelectuales brasileños para su obra, los años 70 del siglo XX y los años 2000. En este primer periodo se observa que fueron traducidas las obras del escritor francés que mejor corresponden a los anhelos de los intelectuales brasileiros por las teorías prove-nientes de los estudios lingüísticos, suficientemente versátiles para basar analíticamente la lectura de los más variados objetos.Ya en el segundo periodo, el interés en la obra de Barthes se fundamenta en la canonización impuesta por la postmodernidad. Tanto en el primero como en el segundo momento, las traduc-ciones de textos barthesianos reflejan diferentes imágenes del escritor francés, construidas por los intelectuales brasileños, que muestran las características de cada uno de esos momentos de la historia cultural del país de acogida

Diatom associations in shelf waters off Paraná State, Southern Brazil: annual variation in relation to environmental factors

A variação sazonal das diatomáceas em águas neríticas do estado do Paraná, Sul do Brasil, foi investigada para analisar sua dinâmica temporal e detectar as principais forçantes ambientais da comunidade planctônica. Picos de biomassa ocorreram de Maio a Agosto e de Dezembro a Março. As espécies dominantes foram Cerataulina pelagica, Chaetoceros spp., Dactyliosolen fragilissimus, Guinardia striata, Lauderia annulata, Leptocylindrus spp., Pseudo-nitzschia cf. delicatissima, P. australis, Rhizosolenia spp., Skeletonema costatum e Thalassionema nitzschioides. Representantes de Naviculaceae, Nitzschia spp., Thalassiosira spp. e Chaetoceros cf. tenuissimus dominaram as diatomáceas nanoplanctônicas. As concentrações da maioria das espécies decresceram durante e logo após as florações de Phaeocystis pouchetii em Setembro, e de Coscinodiscus wailesii em Abril. Com base na análise de cluster e interpretações dos parâmetros ambientais monitorados, seis associações de diatomáceas foram discernidas. Quatro fatores ambientais principais foram atribuídos como determinantes para o grupamento: (a) influência mais forte de águas oligotróficas da Corrente do Brasil na Primavera/Verão, (b) alternância entre as estações chuvosa (rica em nutrientes) e seca, (c) influência de águas subantárticas enriquecidas misturadas às costeiras no Outono e Inverno, trazendo espécies de águas frias, além de promover o crescimento de autóctones, e (d) florações de espécies nanoplanctônicas (Phaeocystis) e microplanctônicas (C. wailesii).The seasonal variation of diatoms in the inshore waters off Paraná State, Southern Brazil was investigated to analyse their temporal dynamics and to detect the main environmental constraints of the planktonic community. Biomass peaks occurred from May to August and from December to March. Among the microplanktonic diatoms, Cerataulina pelagica, Chaetoceros spp., Dactyliosolen fragilissimus, Guinardia striata, Lauderia annulata, Leptocylindrus spp., Pseudo-nitzschia cf. delicatissima, P. australis, Rhizosolenia spp., Skeletonema costatum and Thalassionema nitzschioides were dominant species. Nanoplanktonic diatoms were dominated by Naviculaceae, Nitzschia spp., Thalassiosira spp. and Chaetoceros cf. tenuissimus. Concentrations of most of the species decreased during and just after the blooms of Phaeocystis pouchetii in September and of Coscinodiscus wailesii in April. Based on cluster analysis and interpretations of the environmental parameters monitored, six diatom associations were discerned. Four main environmental factors were attributed as the determinants for the grouping: (a) the stronger influence of the tropical oligotrophic waters of the Brazil Current in spring/summer, (b) the alternation between dry and rainy (nutrient-richer) seasons, (c) the influence of subantarctic waters mixed with coastal ones in fall/winter, bringing cold species and promoting the growth of autochthonous species, and (d) the blooms of nanoplanktonic (Phaeocystis) and microplanktonic (C. wailesii) species

Latitudinal patterns and interannual variations of spring phytoplankton in relation to hydrographic conditions of the southwestern Atlantic Ocean (34°-62°S)

In the present study, the distribution and abundance of microphytoplankton were assessed in the southwestern Atlantic Ocean from subtropical to polar waters (34°–62°S) in two austral springs with contrasting hydrographic conditions. Vertical profiles of open-ocean (ca. 54°W) samples (≥ 18 L filtered water) were performed in 20 stations (0–100 m) in 1994 and in 17 stations (0–50 m) in 1995. The latitudinal patterns of microphytoplankton groups, chlorophyll a, and diatom and silicoflagellate species were analyzed and compared with our previous study carried out in spring 1993 (30°–61°S). In the three springs, 197 diatom species, 173 of which showed mean relative density lower than 1 %, were identified. A consistent diatom biogeographic pattern emerged in the three consecutive springs, defining the Transitional (corresponding to the Brazil–Malvinas Current Confluence), Subantarctic and Antarctic Zones; and the Subantarctic and Polar Fronts, as their boundaries. This zonation reflects persistent features of this hydrographically heterogeneous region. The Polar Front was a weaker biogeographic boundary for diatom species than the Subantarctic Front. Interannual changes in diatoms (mainly in species richness, dominant species and degree of dominance of species with different ecological affinities) were detected. The Transitional Zone, which is one of the most hydrographically variable regions of the world ocean, showed the highest changes in the diatom assemblage, reflecting a colder spring in 1995 and a warmer spring in 1994 than normal (1993). These changes agreed with differences reported for 1993–1995 in large-scale hydrographic conditions, including a widespread diversity decrease in 1995 due to a weaker influence of subtropical waters.Fil: Olguin Salinas, Hector. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales ; ArgentinaFil: Brandini, Frederico. Universidade de Sao Paulo; BrasilFil: Boltovskoy, Demetrio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales ; Argentin