VARIÁVEIS FÍSICAS E QUÍMICAS DA ÁGUA SOB A ABUNDÂNCIA DAS ASSEMBLÉIAS FITO E ZOOPLANCTÔNICAS EM UM LAGO ARTIFICIAL RASO

Abstract

This research evaluated the influence of physics and chemistries
variables of the water under temporal variation in abundance of phyto and
zooplankton assemblages in an artificial shallow environment, the Diva Paim Barth Municipal Lake, Toledo, Paraná. In three sites, samplings were taken
monthly between July and December 1999. Variables analyzed included
alkalinity, turbidity, pH, electrical conductivity, dissolved oxygen, total
phosphorous (organic and inorganic), ammonia, water transparency and
temperature. Assemblage’s abundance was evaluated as density. Significant
temporal differences in the density of planktonic assemblages were observed
during the period. A canonical correspondence analysis (CCA) showed that
the distribution and abundance of phyto/zooplankton are influenced by
turbidity, alkalinity, temperature, ammonia concentration and water
transparency. Therefore, we can conclude that seasonal variations in physical
and chemical characteristics of the water significantly affect the abundance
of phyto/zooplankton assemblages in artificial shallow systems.