The zooplankton of a hipereutrophic shallow lake of the central region of Argentina: changes after one decade
Keywords:shallow lakes, zooplankton biomass, change, one decade after
AbstractThe water bodies ecology is influenced by the contributions of nutrients from the basin. The shallow lentic ecosystems generally presents high levels of eutrophy, which allows to sustain a highly productive zooplanktonic fauna. According to the model of the alternative states of shallow lakes, zooplankton of these environments is characterized by a taxonomic composition, a spectrum of sizes and therefore a biomass that depends on the fishes present. Although in Argentina these ecosystems are abundant and of their importance given by their productivity, diversity and by their recreational and tourist interest, only recently they have begun to be studied. This contribution must by objective give information collected during 2006, by means of monthly samplings of water and zooplankton, on the factors of limnologic importance, their variation and influences on the water transparency and the abundance and zooplanktonic biomass of a shallow urban hipereutrophic lake of La Pampa province and to compare the situation registered with a similar study made between 1995 and 1996. The lagoon is characterized by low salinity and transparency and the reduction of these parameters between both periods studied. The nutrients concentration is greater than the verified in similar environments of Buenos Aires province. Although during both periods the species number was the same, it was verified changes in the taxonomic composition, registering in 2006 smaller number of cladocerans and greater of rotifers and the absence of Daphnia species, which can contribute to the reduction of the water transparency in this period. The found species were of small size, typical characteristic of zooplankton under fish predation. Between both periods a reduction in the abundance of the zooplankton community was verified, mainly between the cladocerans and rotifers.
How to Cite
Echaniz, S. A. (2008). The zooplankton of a hipereutrophic shallow lake of the central region of Argentina: changes after one decade. Biota Neotropica, 8(4). Retrieved from //www.biotaneotropica.org.br/BN/article/view/440