Data/hora: 06/06/2024 08:24:24

Provedor de dados: | Acta Botanica Brasilica
País: | Brazil
Título: | Spatial-temporal variation in coiled and straight morphotypes of Cylindrospermopsis raciborskii (Wolsz) Seenayya et Subba Raju (Cyanobacteria)
Autores: | Dantas,Ênio Wocyli; Bittencourt-Oliveira,Maria do Carmo; Moura,Ariadne do Nascimento.
Data: | 2010-06-01
Ano: | 2010
Palavras-chave: | Cylindrospermopsis raciborskii; Semi-arid; Diel variation; Vertical variation.
Resumo: | This study reports the spatial and temporal behavior of straight and coiled morphotypes of C. raciborskii in a reservoir in Brazil's semi-arid region as well as the main factors responsible for the variability. Two set of samples were collected from the subsurface and bottom in the central region of a reservoir in two seasonal periods (dry - January 2005; rainy - June 2005) over 20-hour sampling periods during daylight (8 am, 12 pm and 4 pm) and dark (8 pm, 12 am and 4 am) hours. Measurements of abiotic parameters were determined concurrently to the sampling of biotic variables. Two C. raciborskii morphotypes were found in the reservoir: straight and coiled. There was no difference in density of the straight and coiled C. raciborskii morphotypes between the different sampling times for either season. Vertical differences were found in the distribution of both morphotypes in both seasons, with greater densities recorded at the subsurface. Densities of the two C. raciborskii morphotypes were greater in the dry season, with the density of the coiled morphotype at the surface two-fold greater than that of the straight morphotype and that found in the rainy season. The ecological success of the coiled morphotype was due to thermal stratification, whereas a mixed condition was determinant in the success of the straight morphotype.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062010000200028
Editor: | Sociedade Botânica do Brasil
Relação: | 10.1590/S0102-33062010000200028
Formato: | text/html
Fonte: | Acta Botanica Brasilica  v.24 n.2 2010
Fonte: | info:eu-repo/semantics/openAccess