SciELO - Scientific Electronic Library Online

 
vol.28 issue3Macroinvertebrates associated with bryophyta in a first-order Atlantic Forest streamMacrobenthic community structure in a Brazilian chocked lagoon system under environmental stress author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Services on Demand

Journal

Article

Indicators

Related links

Share


Zoologia (Curitiba)

Print version ISSN 1984-4670

Abstract

SOUZA, Leonardo C. e; BRANCO, Christina W. C.; DOMINGOS, Patrícia  and  BONECKER, Sérgio L. C.. Zooplankton of an urban coastal lagoon: composition and association with environmental factors and summer fish kill. Zoologia (Curitiba, Impr.) [online]. 2011, vol.28, n.3, pp.357-364. ISSN 1984-4670.  http://dx.doi.org/10.1590/S1984-46702011000300010.

Zooplankton may be regarded as a sensitive tool for monitoring environmental variations in coastal lagoons due to their ability to immediately react to changes in the water column trophic features and salinity levels. As a coastal lagoon with a broad history of anthropic influence, Rodrigo de Freitas Lagoon (Rio de Janeiro, Brazil) is widely used for water sports and artisanal fishing. The present study aimed to expand the knowledge base about zooplankton in the Rodrigo de Freitas Lagoon by assessing the composition and time-spatial distribution of the major zooplankton groups. Samples were collected fortnightly from at four distinct sampling points August 2001 to July 2002. At each point, salinity, temperature, dissolved oxygen and water transparency were measured. During the study period, the lagoon behaved as an spatially homogeneous environment in what regards the abiotic variables. However, all these variables showed significant differences along the time, mainly related to seasonality (air temperature and rainy and dry periods). The zooplankton community showed low taxonomic richness, with the predominance of species commonly found in coastal lagoons, especially with mesohaline conditions, as well as those found in estuaries. An interesting fact was the rise in zooplankton abundance at all sampling points right after a fish kill event. Such increase was caused mainly by the Brachionus plicatilis O.F. Müller 1786 species. Thus, the zooplankton community was affected by physical and chemical factors, mainly by the dissolved oxygen decline event and variations in the influx of seawater into the lagoon. In addition, phytoplankton availability and fish predation pressure were suggested as important regulating factors of the zooplankton community.

Keywords : Brachionus plicatilis; dissolved oxygen; fish mortality; mesohaline; shallow waters.

        · text in English     · English ( pdf )

 

Creative Commons License All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License