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Lira,Giulliari A. S. T.; Araújo,Elcida L.; Bittencourt-Oliveira,Maria Do Carmo; Moura,Ariadne N.. |
The present study reports the phytoplankton abundance, dominance and co-existence relationships in the eutrophic Carpina reservoir, Pernambuco, Brazil. Sampling was carried out at six different depths bimonthly at a single reservoir spanning two climatic periods: dry season (January, September, and November 2006) and rainy season (March, May, and July 2006). Density, abundance, dominance, specific diversity and equitability of the community were determined, along with chlorophyll a, and physical and chemical variables of the environment. Eight species were considered abundant, and their densities corresponded to more than 90% of the total phytoplankton community quantified. Cyanobacteria represented more than 80% of this density. Cylindrospermopsis... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Carpina reservoir; Cylindrospermopsis raciborskii; Cyanobacteria; Limnological characteristics; Phytoplankton structure; Vertical distribution. |
Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652011000400018 |
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Pedrozo,Catarina da Silva; Rocha,Odete. |
The purpose of the present work was to evaluate the environmental quality of Marcelino, Pinguela, Peixoto, Palmital, Malvas and Do Passo lakes, interconnected by canals and located in the district of Osório, RS. In this context, 29 physical and chemical variables were analyzed with sampling carried out in January, May, July and October 1997 to verify the environmental quality of the system and the existence of a gradient of quality. Canonical Analysis was applied to the data of all environmental variables measured, and showed that the lakes had different characteristics as a consequence of the organic pollution received. Marcelino lake received continuous input of organic matter from the sewage treatment works in the town of Osório, whereas Peixoto,... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Castal lakes; Water quality; Environmental variables; Limnological characteristics. |
Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132007000400013 |
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SIPAÚBA-TAVARES,L. H.; FREITAS,A. M.; BRAGA,F. M. S.. |
Due to the increasing use of artificial aerators in fish ponds, and to the lack of studies on this subject, this work studied some of the aspects associated with their use. The influence of a diffuser type aerator (AR 120) on the biotic and abiotic variables was evaluated in a fish pond. Three points of the pond were marked for the taking of samples: 5, 10 and 23 m from the aerator. Samples were taken every day for 15 consecutive days: 5 days before the use of the aerator, 5 days with the aerator functioning and 5 days with it not functioning. The limnological variables studied did not show significant differences (P > 0.05) when the three sampling points were compared, but regarding the use of the aerator, variables such as water temperature,... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Mechanical aeration; Limnological characteristics; Pond. |
Ano: 1999 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0034-71081999000100005 |
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