Abstract:

Samples of zooplankton were taken from Hoşrük Stream between March 2104 and February 2015 at 3 stations on a monthly basis. Water temperature, dissolved oxygen and pH values are determined from the stream by portable measuring devices. Shannon Wiever (H'), Simpson (D) and Margalef (M) index values are calculated monthly using the relevant formulas. A total of 28 zooplankton species were identified during the survey. There are 18 species of Rotifera, 8 species of Cladocera and 2 species of Copepoda. Rotifers took the first place in terms of both number of taxa, number of individuals and frequency of occurrence. Polyarthra dolichoptera from rotifers has been detected in 10 samples and is the most common species among all zooplankton species. Cyclops vicinus from Copepoda was the second dominant species observed for 9 months. May was the month in which the maximum number of taxa (20 species) was recorded, least taxa (2 species) was recorded in January. Shannon Wiever species richness index value (H') reached the highest value of H' = 1.51 in July. The Margalef index value was also calculated as M = 2.22 at the highest at May, Simpson index value D = 0.89 calculated in its highest level at March. Determination of low H' index values were indicating that stream is poor in terms of species diversity.

Keywords: