Phytoplankton community of Reis Lake in the Brazilian Amazon.
An Acad Bras Cienc
; 85(2): 649-63, 2013.
Article
em En
| MEDLINE
| ID: mdl-23828365
Reis Lake is located in the municipality of Caracaraí, state of Roraima (Brazil) and is subject to fluctuations in water level. The aim of this study was to analyze the structure of the phytoplankton community on the nictemeral and seasonal scales and determined the influence of limnological variables. Sampling was performed in the rainy season (June/2006) and dry season (November/2006), considering two nictemeral cycles. The phytoplankton community was assessed with regard to composition and density, abiotic variables were analyzed simultaneously. The lake had low concentrations of oxygen, clinograde profile and water stratified during the day and homogenous at night, with low concentrations of nutrients and waters ranging from slightly acidic to alkaline. The phytoplankton was represented by 43 taxa, 35 species in the dry season and 29 species in the rainy season. Low densities of phytoplankton occurred in both nictemeral cycles, with accentuated vertical gradient. The highest densities were recorded in the dry season. Reis Lake exhibits characteristics that classify it as a polymythic and oligotrophic environment. The variability in the data was more important seasonally than on the nictemeral scale, supporting the hypothesis of the influence of the hydrological cycle on the dynamics of phytoplankton communities in floodplain lakes.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Fitoplâncton
/
Lagos
País/Região como assunto:
America do sul
/
Brasil
Idioma:
En
Revista:
An Acad Bras Cienc
Ano de publicação:
2013
Tipo de documento:
Article
País de afiliação:
Brasil
País de publicação:
Brasil