PHYTOPLANKTON DYNAMICS IN A FRESH WATER AQUATIC BASIN
Valerica Gîlcă, I. Gîlcă
In order to determine the composition of phytoplankton in fish tank in the village Ezareni were first established sampling stations. For this purpose, samples were collected in three ways: in the upstream and downstream and in the central area. Were established the sampling periods depending on algae biomass dynamics. For detailed qualitative and quantitative study of phytoplankton samples were collected monthly (three months). To determine plankton were collected, each time, samples per liter of water. The materials that were used to determine the quality of phytoplankton were plantonic net, batometric glass, bottle with glass stopper or PVC bottles, fixing solution (formalin, IIK), microscope, glass slides, dyes, determination. Sampling was done differently depending on where and how the sample collection. Thus, samples were taken directly into the sample bottle, from water surface or from batometric glass when water was collected at various depths. Fixation tests aimed at preserving planktonic organisms able morphological state at the time of collection. Fixation was done with 4% formalin solution at a rate of 25 ml to 1 liter of water or withn solution of iodine in potassium iodide in the range of 5 ml per 1 liter of water. Samples were analyzed under a microscope and noted species were found. Finally was pepared a list of species of algae exist in the ecosystem, called abstract floral list. The research results showed that in May there was the largest number of idividuals of phytoplankton (5557), and the lowest number of individuals was determined in April (5580). On taxonomic group found that in April the bacilarioficee were most abundant, followed by cloroficee, and cianoficee were the least abundant. In May all bacilarioficee were most numerous, followed by cloroficee and cianoficee. In June, clorofite were very abundant, cianofite abundant and less abundant were bacilarioficee.
Key words: pool, phytoplankton, dynamics, water