53 research outputs found

    Dissolved inorganic nutrients and chlorophyll on the narrow continental shelf of Eastern Brazil

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    The eastern Brazilian continental shelf is narrow and subject to the influence of a western boundary current system, presenting lower biological productivity than other regions. In this study, the distribution of water masses, dissolved inorganic nutrients, chlorophyll-a and total suspended solids (TSS) on the inner shelf (< 35 m depth), between Itacaré and Canavieiras, eastern Brazil, is presented. Sampling surveys were carried out in March and August 2006 and March 2007. Tropical water (TW) prevailed during March 2006 and August 2007 with the lower salinity waters (< 36) found in most samples taken in March 2007, reflecting the influence of continental outflow and rain in coastal waters. Low concentrations of dissolved inorganic nutrients and Chl-a found were typical of TW and results suggested that the inner shelf waters were depleted in dissolved inorganic nitrogen in August 2006 and March 2007, and in phosphate in March 2006, potentially affecting phytoplankton growth. Stratification of the water column was observed due to differences in dissolved nutrient concentrations, chlorophyll-a and TSS when comparing surface and bottom samples, possibly the result of a colder water intrusion and mixing on the bottom shelf and a deep chlorophyll maximum and/or sediment resuspension effect. Despite this stratification, oceanographic processes such as lateral mixing driven by the Brazil Current as well as a northward alongshore drift driven by winds and tides transporting Coastal Water can lead to an enhanced mixing of these waters promoting some heterogeneity in this oligotrophic environment

    Standing-stock and potential of phytoplankton production in the Bay of Santos, Brazil

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    Phytoplankton primary production and the maximum photo synthetic index (Pb m) from the region of Bay of Santos were measured every two months during 1976 by simulated incubations using 14C method and incandescent lamps (737 µE.m-2 .s-140 klux) . The results obtained for production rates (maximum of 204.6 mgC.m-3.hr-1 in winter and 488.3 mgC m-3.hr-1 in summer) are among the highest recorded for tropical marine environments. A high capability of light adaptation under high temperatures was also verified. The photo synthetic indexes obtained were also very high and seems to be due to the high nutrient level of the region. The eutrophic state is supported by the high nutrient and chlorophyll-a concentrations and by the phytoplankton cells number

    Serum acute phase proteins in cows with SARA (Subacute Ruminal Acidosis) suspect

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    The aim of this study was to evaluate the variations of Acute Phase Proteins (APPs) and other blood constituents during the onset of the sub-acute ruminal acidosis (SARA) pathological status. A total of 108 cows from 12 dairy herds were randomly selected and divided into three Groups of 36 animals each. All animals were subjected to a rumenocentesis. Group A was composed by subjects with a rumen pH>5.8, Group B was composed by subjects with a rumen pH ≤5.5≤5.8 and Group C was composed by subjects with a rumen pH<5.5. Blood samples were collected by jugular venipuncture and Haptoglobin (Hp), Serum Amyloid A (SAA), Total Proteins, Albumin and White Blood Cells (WBC) were determined. One-way ANOVA showed a statistical significance on Rumen pH, Hp, SAA. SARA seems not stimulate the APPs production from liver

    Review Of Ecotoxicological Studies Of The Marine And Estuarine Environments Of The Baixada Santista (São Paulo, Brazil)

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    The aim of the present study was to identify, through ecotoxicological assays, the most critical areas in the Baixada Santista area by compiling scientific papers and technical reports of the state environmental agency. Sediment samples were assessed employing Tiburonella viscana, Leptocheirus plumulosus, Nitokra sp., and embryos of Lytechinus variegatus and Perna perna. Water column samples were assessed by using Vibrio fischeri and Lytechinus variegatus. A total of 217 samples were compiled. It was found that the frequency of acute toxicity was higher in integral sediment samples from the Santos Channel (70.68%) and the lowest frequency was obtained for Bertioga beach samples (15%). Sediment from the Santos and São Vicente Channels, Santos Bay and the area for the disposal of dredged material are the places most affected, whereas the beaches of Guarujá and Bertioga presented low levels of toxicity. No ecotoxicological studies were found in Mongaguá, Itanhaém or Peruíbe cities

    Dilatação dos confins: caminhos, vilas e cidades na formação da Capitania de São Paulo (1532-1822)

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    Este ensaio analisa a formação da rede urbana das capitanias de São Vicente e Santo Amaro, depois unidas na Capitania de São Paulo. Discute o processo de apropriação do sertão, a pulsação e dilatação dos confins ao sabor dos deslocamentos humanos e de interesses políticos. Interpreta o papel de capelas, freguesias, vilas e cidades no controle e produção de territórios metropolitanos em solos ultramarinos.This essay analyzes the development of urban networks in the Captaincies of São Vicente and Santo Amaro, later merged into the Captaincy of São Paulo. It discusses the process of appropriation of the sertão (backcountry), the commotion and expansion beyond the confines to the tune of population movements and political interests. The paper also interprets the role of chapels, parishes, villages and towns in initiatives to create and control metropolitan areas on overseas soil
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