Kisand, Veljo, juhendajaTenno, Taavo, juhendajaFurkan, KaradenizTartu Ülikool. Loodus- ja täppisteaduste valdkondTartu Ülikool. Tehnoloogiainstituut2023-06-202023-06-202023https://hdl.handle.net/10062/90777Phosphate-accumulating organisms (PAOs) are diverse bacteria that retain phosphate as polyphosphate. These bacteria play an essential role in various water treatment plants beca- use they are used effectively to remove a proportion of the phosphorus in wastewater. Was- tewater treatment plants (WWTPs) are vital in today's world, and the significance of phosp- hate in our lives and its relationship with these bioorganisms formed the main idea of this project. These plants use physical, chemical or biological methods to treat wastes in the water, and the abundance of these organisms will differ as each treatment plant has different management and environmental conditions. Therefore, in this study, biological detection of these organisms and a comparison of their abundance in several different wastewater treat- ment plants were carried out. Comparisons using a confocal microscope showed the same results trend when samples that had already been chemically measured were observed under the microscope stained with DAPI (4',6-Diamidino-2-phenylindole). The confocal micros- cope was successfully utilized to detect these organisms in the sludge in the wastewater. The comparison of these treatment plants regarding the abundance of these organisms and flow cytometry data was successfully performed.engopenAccessAttribution-NonCommercial-NoDerivatives 4.0 Internationalphosphate accumulating organismswastewater treatment plantsDAPIdetectionmagistritöödThesis