RESEARCH ON THE SPECTRUM OF A TAXONOMY OF AQUATIC BIOCOENOSIS
Valerica Gîlcă, I. Gîlcă
Research goal is to determine the taxonomic spectrum of a freshwater aquatic ecosystem. Research were conducted in the resort of Research and Development Station for Aquaculture and Aquatic Ecology Iasi for a period of 48 days, starting on 1 June 2011 until 18 July 2011. Taxonomic and ecological spectrum of biocenosis is the percentage of various systematic units or environmental groups represented as ciclograme. To establish the taxonomic spectrum of a biocoenosis were collected several samples of phytoplankton, zooplankton and benthos, was done the systematic classification of species groups and then determined the abundance for each taxon or systematic group and dominance was calculated in percent. Processing samples in laboratory consists in the sedimentation for 21 days and centrifuged at 1500 rpm/min for 5 minutes. Numerical assessment and species identification was made in a laboratory using the HC 1 microscope and a counting chamber. Research conducted to determine the structure of biocenosis and drawing taxonomic spectrum of aquatic ecosystems studied in summer 2011 showed that phytoplankton species are present in highest proportion followed by zooplankton and benthonic organisms. Regarding the increased proportion of phytoplankton, whilst investigations point out that it is during the propagation, there actually is a positive correlation between phytoplankton, zooplankton and benthos.
Key words: aquatic, species, taxon, range, ecosystem