Macroinvertebrates on Eichhornia crassipes roots in two lakes of the Paraná River floodplain

摘要: Changes in the abundance, biomass and relativeproportions of functional feeding groups ofmacroinvertebrates were studied for 17 months duringlow high water periods two floodplain lakeswith indirect connections to Parana River.At low water, Eichhornia crassipes root clusterswere colonized by comparatively densities ofmacroinvertebrates, especially lake moredistant river. Collector-gatherers andpredators most abundant feedinggroups, but different taxa these dominatedin lakes during water.At macroinvertebrates increasedas a result increased flow through roots. Inthis period, collector-filterers dominated at bothlakes constituted over 34% themacroinvertebrates. Four independent variables(conductivity, hydrological periods, dissolved oxygenand site) explain 87% variability inmacroinvertebrates density expressed as number ofindividuals per m2. No significant relationshipwere found between macroinvertebrate anyof variables.