Özet:
As the benthic diatom communities respond quickly even in the minor changes of the nature of water, they are used as an indicator of aquatic systems very commonly. Although there are numerous studies widely used in the determination of eutrophication, their reactions to herbicides have been studied recently. For this reason, in order to contribute to these studies, the doses of 10, 25, and 50 ppm were applied on epilithic diatoms based on the estimated transition doses to the aquatic system after using ECHO-5 very commonly utilized in agriculture. As a result, the total organism changes and pigmentation differences were examined. Totally 23 species were identified, the total organism amount decreased rapidly depending on the concentration increase. The species included in Cyclotella, Navicula and Nitzschia were dominant genera and Cyclotella meneghiniana (Katz.), Nitzschia palea (Kiitzing) W. Smith and Navicula cryptocephala (Katz.) species showed variabilty. The average chlorophyll contents became 40.5 mu g/l in the control group, they fell to 23.6 mu g/l in the application with 10 ppm, to 23.5 mu g/l in the application with 20 ppm and to 12.6 mu g/l in the application with 50 ppm.