Seasonal Changes in the Vertical Distribution of Rotifers in a Eutrophic Shallow Lake with Contrasting States of Clear and Turbid Water

Monthly zooplankton samples were taken from a shallow Argentinean lake in 1997- 1998, and spatiotemporal changes in rotifers in the water column were examined. The most abundant and frequent species were Brachionus calyciflorus, B. caudatus, B. havanaensis, Keratella tropica, Filinia longiseta, and...

ver descrição completa

Detalhes bibliográficos
Autores: Claps, María Cristina, Gabellone, Néstor Adrián, Benítez, Hernán Hugo
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2011
País:Argentina
Recursos:Universidad Nacional de La Plata
Repositorio:SEDICI (UNLP)
Idioma:inglés
OAI Identifier:oai:sedici.unlp.edu.ar:10915/119655
Acesso em linha:http://sedici.unlp.edu.ar/handle/10915/119655
Access Level:acceso abierto
Palavra-chave:Ciencias Naturales
Rotifers
Vertical profile
Eutrophic shallow lake
Argentina
Clear and turbid water
Descrição
Resumo:Monthly zooplankton samples were taken from a shallow Argentinean lake in 1997- 1998, and spatiotemporal changes in rotifers in the water column were examined. The most abundant and frequent species were Brachionus calyciflorus, B. caudatus, B. havanaensis, Keratella tropica, Filinia longiseta, and Polyarthra vulgaris. These perennial species are considered to be common in eutrophic waters, are eurytopic, and are widely distributed. The phytoplankton composition, competition for food with other grazers, and predation pressure, plus the occurrence of different periods including a turbid phase, a phase with coverage of submerged macrophytes (Potamogeton pectinatus), and a flooding phase, defined the annual planktonic rotifer succession in the lake. Small-scale vertical distributions of rotifers in this homothermal lake were related to both biotic and abiotic forces. The presence of macrophytes favored an increase in planktonic-rotifer densities along with a specific richness associated with the possibility of refuge, the incorporation of littoral species, and food diversification.