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A ictiofauna de áreas rasas do complexo estuarino baía de Paranaguá, Paraná
(Universidade Federal de São Carlos, 2004-04-15) Fávaro, Luís Fernando; Verani, Nelsy Fenerich; https://lattes.cnpq.br/1862746100743391
The present work investigated the ichthyofauna in the shallow waters of the Paranaguá Bay estuarine complex, Paraná state, Brazil, considering eight sample sites along the north-south axis. The analyses of the physical and the chemical data series of the water and the biological data monthly obtained, taking in account the sediment data series seasonally determined in each site, making possible the environmental characterization and the quali-quantitative assessment of the local ichthyofauna. The hydrological parameter values reflecting an environmental gradient defined by the increasing from the north to the south region of the estuary. The northern sample sites were characterized by higher continental water influence, lower hydrodynamic and higher fine granules amount in the sediment. The biological data analyses of the ichthyofauna in the studied area showed that the complete life cycles of some species take place in this area, emphasized by the relevant occurrence frequencies of juvenile and adult specimens. In the meantime, the highest values of the hydrological parameters were registered on the southern sample sites of the estuary, showing the influence of the marine salt water and characterized by the higher hydrodynamic forces reflected by the high amount of thick granules in the sediment. The ichthyofauna is mainly represented by juvenile fish of marine species that utilize the estuary in some periods of the year and by sporadic marine species. The shallow water ichthyofauna of the Paranaguá Bay estuarine complex is composed by 96 species with predominance of occasional species in comparison to the constant ones, indicating a dynamic environment. The quantitative data analyses of the ichthyofauna showed seasonal differences as in the species composition as in the catch proportion, resulting in a seasonal characterization of the specific richness, of the species diversity, of the eveness and of the similarity indices. The results of the present study emphasize the spatial-temporal heterogeneity of the environment, taking in account its characteristics and the ichthyofauna composition, revealing that the shallow waters of Paranaguá Bay estuarine complex constitute a highly dynamic environment.
Atropelamento de vertebrados silvestres em uma região fragmentada do nordeste do estado de São Paulo: quantificação do impacto e análise de fatores envolvidos
(Universidade Federal de São Carlos, 2004-04-15) Prada, Cristiana de Santis; Pires, José Salatiel Rodrigues; https://lattes.cnpq.br/3412204514901170
Mortality due to road kills has a great impact on natural populations. The present work had the objectives of quantifying road-killed vertebrates in a circuit of the main highways of northeastern São Paulo State, a fragmented area with several unconnected Conservation Units, and to identify factors associated with this source of mortality. For the count of road-killed animals, 52 weekly trips were performed during one year (August 19, 2002 to August 11, 2003) in a circuit of the highways SP253, SP330, SP215, SP310, SP215, SP318, SP255. The species encountered were classified in numbers of one to five, in decreasing order, according to the priority of its conservation in the area. The results from the trips were 596 animals of 81 different species: birds, 310 (52% of the total, 45 identified species); mammals, 184 (31%, 23 species); reptiles, 56 (9%, 11 species); amphibians 35 (6%, 2 species); and 11 (2%), not identified. Considering the 239,24km of the circuit 2,49 animals/km/year were killed. Considering the total effort of 12.440,48km traveled, an average of 0,048animals/km was obtained. These data were added to those supplied by other sources of information, yielding records of 746 animals: 323 birds, 266 mammals, 94 reptiles, 35 amphibians and 28 not identified. In a general way there was smaller number of road-kills in the dry period than in the rainy season, but there was great variation among some species, apparently related to their natural history. The most-frequently found species was the opossum (Didelphis albiventris), with 53 records, in other words, 28,8% of the total of mammals, 8,89% of the total of animals. The Order Carnivora had the largest number of road-killed species (4) among the mammals. There were records of threatened species at the São Paulo State such as the Maned-wolf (Chrysocyon brachyurus), Ocelot (Leopardus pardalis), Giant anteater (Myrmecophaga tridactyla) and Broad Snouted Caiman (Cayman latirostris) and of species that don't occurr naturally in the State. It was found that 70,21% of the animals of categories 1 and 2 (i.e. conservation priorities in the area) died in 47%, or 111,72km of the studied itinerary. This road segment is at a maximum distance of 10km from the nearby Conservation Units, or 5km from the river Mogí-Guaçu. Mitigatory measures were discussed, and four prioritary areas for their establishment were proposed.
A transformação de Darboux-Bianchi para superfícies isotérmicas em R³
(Universidade Federal de São Carlos, 2004-04-15) Canevari, Samuel da Cruz; Figueiredo Junior, Ruy Tojeiro de; https://lattes.cnpq.br/9930999514347198
In this work we develop the transformation theory for isothermic surfaces in Euclidean space IR3 due to Darboux and Bianchi. As a consequence, we describe a method for constructing new solutions of the nonlinear system of partial diferential equations associated to an isothermic surface in IR3 starting from a given one.