Navegando por Palavras-chave "Billings reservoir"

Agora exibindo 1 - 2 de 2
  • Imagem de Miniatura
    Item
    Acesso aberto (Open Access)
    O fitoplâncton como ferramenta para o monitoramento das águas no Reservatório Billings (Diadema/SP)
    (Universidade Federal de São Paulo, 2016-02-05) Moutinho, Fellipe Henrique Martins [UNIFESP]; Nordi, Cristina Souza Freire [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    The Billings Complex is a strategic reservoir of the Metropolitan Region of São Paulo (MRSP), which waters are destined for multiple uses: from the generation of electricity to the public supply. Facing one of the biggest water crisis in the State of São Paulo, which lasted from 2013 to the beginning of 2016, the Billings reservoir was considered a promising alternative to public water supply. The characterization and the use of methods to monitor the water quality of the reservoir waters are needed, such as the use of biological indicators as phytoplanktonic community. This study aimed to monitor the physical, chemical and biological parameters, using the phytoplanktonic community to evaluate water quality. The samples were collected monthly, from June 2014 to July 2015, at one Billings Reservoir point (EMI ? UNIFESP). The profiling of four variables (temperature, pH, electrical conductivity and dissolved oxygen) were analyzed in situ using multi-parameters probes. The transparency and the depth of the water column were measured with a Secchi disk. The water samples for nutrient analysis, total solids, chlorophyll-a and phytoplankton density were taken at three different depths. A plankton net was used in order to gather samples for phytoplankton qualitative analysis. 135 taxa were identified, which are distributed in 10 classes: Cyanophyceae, Chlamydophyceae, Chlorophyceae, Zygnemaphyceae, Dinophyceae, Euglenophyceae, Cryptophyceae, Xanthophyceae, Chrysophyceae and Bacillariophyceae. The total phosphorus, chlorophyll-a and cyanobacteria biovolume concentrations were above the limit established by CONAMA (Class II) Resolution n° 357/2005 in the majority of the months sampled. Based on these results the point of Billings Reservoir studied was classified as hypereutrophic. Among the fitoplankton species analysed 20 descriptor species (relative biovolume > 1%) was determined. During the most part of the established time the cyanobacteria were dominant, including among them some potentially toxigenic as: Aphanocapsa annulata, Cylindrospermopsis raciborskii, Dolichospermum planctonicum, Microcystis aeruginosa, M. panniformis, M. protocystis, Planktothrix agardhii, P. isothrix and Raphidiopsis brookii. The dinoflagellate Ceratium furcoides, species considered as invasive in Billings Reservoir, presented well-defined seasonal behavior. The use of biovolume to calculate the diversity index best reflected the water quality. The Multiple Linear Regression tested showed satisfactory preliminary results predicting cyanobacteria variation based on the obtained data, highlighting the ammoniacal nitrogen concentration and temperature as the most relevant factors to the model. The monitoring of water quality of the studied site in the Billings Reservoir revealed a great historical deterioration of water quality. The phytoplanktonic groups Euglenophyceae, Bacillariophyceae, Dinophyceae and Cyanobacteria proved to be great bioindicators for the water quality because of their specific responses to certain environmental changes.
  • Imagem de Miniatura
    Item
    Acesso aberto (Open Access)
    Níveis de concentração de elementos terra raras em sedimentos do Rio Pinheiros, São Paulo
    (Universidade Federal de São Paulo, 2014-09-15) Moura, Rodrigo Reis de [UNIFESP]; Silva, Ivone Silveira da [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    This research had as main objective evaluating the concentrations of Rare Earth Elements (REE) in sediments of the Pinheiros River and Billings Reservoir, SP, correlating the determined concentrations of these elements to their origin as natural sources Rocks Local geological context or were a result of anthropogenic inputs. The sediment samples studied were obtained in two sampling campaigns (one in the dry season and another in the rainy) in 05 (five) collection points along the Upper Canal Pinheiros River, between the Traição and Pedreira pumpings plants, and 01 (one) point in the Billings Reservoir, with short testimonies from 25 cm depth. For chemical analysis, the samples were previously dried at 80°C for 48 hours, and subjected to a digestion procedure with HNO3 and HCL concentrated and H2O2. The extracts were diluted and the determinations of the levels of REE were performed on an ICP-AES. The Rare Earth Elements, also identified as lanthanides (La to Lu) plus Sc and Y are elements that have similar chemical behavior. Order to data interpretation, was made a grouping of REE in Light (La, Ce, Pr, Nd, Pm), Medium (Sm, Eu, Gd, Tb) and heavy (Dy, Ho, Er, Tm, Yb, Lu, Sc, Y). These elements are mainly associated with the mineral group of bastnaesita (CO3F), monazite (PO4) and xenotímio (YPO4). The obtained results highlighted a marked characteristic in REE patterns for sedimentary processes is that the uniformity of the abundance patterns observed in several rock types along the study area that may have a major influence on unit schists of the Embu Complex. Comparing the two sampling campaigns in distinct periods (dry and rainy) showed an increase of the concentration values in the rainy season campaign, especially REE-Light. Several references describe the distinct patterns to REE, which indicate the deposition of these elements in arid conditions, whereas under humid conditions there is a slight tendency for not fractionation due to preferential mobility of REE-light in those conditions. The average values of concentration to REE determined ranged from 0,1 a 15,55 mg.kg-1, especially La, Ce, Pr and Nd with a higher concentration than the other elements of the series. Even so, these levels show a very much close levels of crustal rocks and sediments analyzed in comparative studies. We must also mention the anthropogenic inputs, once the ?flúvio-lacustre? environment has raised a record of physical modifications and severe contamination processes physico-chemical according to the urban and industrial development in the area plain of inundation which contributes to potential sources of REE.