Companhia Energetica de Sao Paulo

Castilho, Brazil

Companhia Energetica de Sao Paulo

Castilho, Brazil
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Garcia C.C.,Companhia Energetica de Sao Paulo | Reis M.G.F.,Federal University of Viçosa | dos Reis G.G.,Federal University of Viçosa | Pezzopane J.E.M.,Federal University of Espirito Santo | And 2 more authors.
Ciencia Florestal | Year: 2011

The current study aimed to analyse the tree species natural regeneration floristic composition in a Mountain Seasonal Semideciduous Forest fragment in the domain of the Atlantic Forest, in southeastern Brazil (20°45'S, 42°55'W) in order to subsidize secondary natural forest management. Ten sites were selected based on their aspects, slopes and topographic positions. Natural regeneration indexes were estimated for each tree species per size classes to obtain the Total Natural Regeneration Index (TNR) for each species. It was sampled a total of 3,516 individuals of 140 tree species varying from 10 cm to 5 m height with diameter at the height of 1.3 m (DBH) smaller than 5 cm. The largest numbers of individuals were sampled in the families Rubiaceae, Fabaceae Mimosoideae, Monimiaceae, Fabaceae Papilionoideae, and the richest families were Fabaceae Caesalpinoideae, Fabaceae Papilionoideae, Euphorbiaceae, Lauraceae, Myrtaceae and Rubiaceae. Psychotria sessilis, Siparuna guianensis, Anadenanthera peregrina and Piptadenia gonoacantha presented the largest TNR. The comparison of the actual regeneration study with that of prior evaluations suggests a continuous substitution of species from initial to more advanced stages. These results indicate that the protection of the remaining forest fragments is important to maintain or improve the biodiversity in this region.

Bianchini I.,Federal University of São Carlos | Cunha-Santino M.B.,Federal University of São Carlos | Milan J.A.M.,Federal University of São Carlos | Rodrigues C.J.,Companhia Energetica de Sao Paulo | Dias J.H.P.,Companhia Energetica de Sao Paulo
Journal of Aquatic Plant Management | Year: 2015

The development of an aquatic community can reflect the anthropogenic influence on adjacent areas of a freshwater system. The understanding of growth rates of a key species is useful for planning management activities. In this study, we used a kinetics model to evaluate growth of three submerged macrophytes: Brazilian elodea (Egeria densa Planch.), narrowleaf elodea (Egeria najas Planch.), and coontail (Ceratophyllum demersum L.) under laboratory conditions that simulate the in situ condition in a Neotropical, constructed lake ecosystem (Jupia Reservoir, Brazil). Incubations were prepared with healthy apical tips of Brazilian elodea, narrowleaf elodea, and coontail (N = 40; 5.0 cm long) in 40 polystyrene pots filled with sediment from the reservoir. A set of 10 pots were placed in a glass tank with 6.5 L of water from the reservoir. The fitting of the data indicated that the growth of macrophytes exhibited an average doubling time (td) between 11.6 (Brazilian elodea) and 23.9 d (coontail) and yields varied between 8.6 (= 52.9 mg; Brazilian elodea) and 19.6 cm (= 217.8 mg; coontail). The growth parameters suggest that these plants have a close niche; however, in Neotropical aquatic systems, these species coexist and compete with other native and aliens submerged species. The floating genus can also present a td with the same order of magnitude as that presented by Egeria and Ceratophyllum. In this case, the floating plants have an advantage in that light is not a limiting factor nor is the shadowing effect that is imposed on submerged species.

Zambon R.C.,University of Sao Paulo | Barros M.T.L.,University of Sao Paulo | Barbosa P.S.F.,University of Campinas | Francato A.L.,University of Campinas | And 3 more authors.
World Environmental and Water Resources Congress 2013: Showcasing the Future - Proceedings of the 2013 Congress | Year: 2013

The Brazilian hydrothermal system consists of a completely linked network of 143 medium and large hydropower plants, 888 small hydropower plants, and 1,602 thermal and 82 wind power plants, with a total installed capacity of 128,570 MW. The hydropower plants produce, on average, 91% of the total electricity consumed in the country, while the complementary thermal system is dispatched mainly during periods of drought. In our previous studies, we developed a nonlinear programming model, HIDROTERM, to optimize the management and operation of the hydrothermal system, considering individual hydropower plants, thermal generation and exchange, multiple uses of the water, and system expansion. The model is deterministic. In this paper, we develop a new version of HIDROTERM to incorporate the stochasticity of the inflows in the formulation. Additionally, hourly load variation is represented by three levels: peak, base, and low. The proposed approach is based on two-stage stochastic programming with recourse. In the first stage (first time period) the system passes from its initial state to the final state based on deterministic inflow forecasts. From the second time period on (the second stage), the state of the system branches out according to inflow scenarios. The branching can be scaled up gradually until the end of the planning horizon. New developments are made in the formulation, interface, database, and the underlying simulation model. The newly developed integrated decision support system is being tested on the entire Brazilian hydrothermal system. © 2013 American Society of Civil Engineers.

Sanches E.A.,Paulista University | Okawara R.Y.,Institute Pesca | Caneppele D.,Companhia Energetica de Sao Paulo | Toledo C.P.R.,West Parana State University | And 2 more authors.
Journal of Applied Ichthyology | Year: 2015

The objective of this study was to assess the effect of storage temperature on the fresh sperm quality of Steindachneridion parahybae over 112 h of storage. Semen collected from five males was tested in a 12 × 4 factorial experimental design using the sperm storage times of: 0 (control), 1, 2, 4, 8, 16, 24, 36, 48, 64, 88, and 112 h after collection. Temperatures tested were (mean ± SD): 5.2 ± 3.4, 12.9 ± 1.6, 24.4 ± 1.7 and 34.9 ± 1.1°C. Sperm parameters were motility rate (MOT), curvilinear velocity (VCL), average path velocity (VAP), straight line velocity (VSL), straightness (STR), sperm normality (NOR) and survival rate (SUR). The parameters VCL, VAP and VSL were grouped by principal component analysis to create the sperm velocity (VS). The parameters assessed exhibited effects (P < 0.05) of the exposure time and temperature. Interactive effects between temperature and time (P < 0.05) were observed for STR, NOR and SUR, and quadratic effects for factors MOT and VS (P < 0.05). Pearson's linear correlation was verified between the parameters studied (P < 0.05), indicating MOT, VCL and STR as good indicators of sperm quality. Chilling at temperatures around 5°C and heating at around 35°C were harmful to S. parahybae spermatozoa. It is suggested that short-term (up to 8 h) semen storage - if necessary - should be within a range of 15-25°C. © 2015 Blackwell Verlag GmbH.

Honji R.M.,University of Sao Paulo | Caneppele D.,Companhia Energetica de Sao Paulo | Moreira R.G.,University of Sao Paulo
Pesquisa Agropecuaria Brasileira | Year: 2013

The objective of this work was to describe the morphology of the gonads of surubim-do-paraíba (F1) during induced breeding in captivity. Thirty females were induced to reproduction using carp pituitary extract and human chorionic gonadotropin. Twenty-eight females responded to the induction, releasing 238.80 g of oocytes (fertilization rate: 24.337plusmn;8.35%). After stripping of gametes, the animals were euthanized for the morphological analysis of the gonads. Testicles did not present morphological alteration after induction. Among ovaries, 63.31% showed malformation (uneven, not uniform development or "narrowing"), and the number of released oocytes was below the obtained in wild broodstock of this species.

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