INVESTIGADORES
O'FARRELL Ines
artículos
Título:
Variation in phytoplankton composition and limnological features in a water-water ecotone of the Lower Paraná Basin (Argentina).
Autor/es:
IZAGUIRRE I.; O'FARRELL I.; TELL, G.
Revista:
FRESHWATER BIOLOGY (PRINT)
Editorial:
Oxford
Referencias:
Año: 2001 vol. 46 p. 63 - 74
ISSN:
0046-5070
Resumen:
1. Structure and dynamics of phytoplankton were studied at six sites in a reach of the
Lower Parana´ River floodplain, from the main course to a marginal shallow lake,
connected through a stream. This system is defined as a waterwater ecotone and
thus, the aim of this work is to analyse the spatial changes of phytoplankton along the
transitional system.
2. Temporal fluctuations in number of species and phytoplankton density were more
pronounced in the river than in the shallow lake. Even though most species were
ubiquitous, there was a clear segregation of the most abundant populations across the
ecotone. Aulacoseira granulata var. granulata and other centric diatoms decreased towards
the lentic system.
3. Transparency varied according to river discharge, being higher in the lake during
high water phases, while the opposite behaviour was observed during dry periods.
These fluctuations were related to precipitation and resuspension processes.
4. Nitrate concentration diminished towards the lake while soluble reactive phosphorus
remained fairly homogeneous across the ecotone.Aulacoseira granulata var. granulata and other centric diatoms decreased towards
the lentic system.
3. Transparency varied according to river discharge, being higher in the lake during
high water phases, while the opposite behaviour was observed during dry periods.
These fluctuations were related to precipitation and resuspension processes.
4. Nitrate concentration diminished towards the lake while soluble reactive phosphorus
remained fairly homogeneous across the ecotone.