Freshwater Cyanobacterial blooms and Cyanotoxin production in Serbia in the past 25 years

Abstract

Since 1980 cyanobacterial blooms occurred in a large number of reservoirs lakes and water flows (rivers and channels) in Serbia. Among 83 water ecosystems examined, 58 were found in blooming condition almost every year during last 2 decades. All natural lakes, accumulations, rivers and canals in Vojvodina province (agricultural part) proved to be sites with frequent cyanobacterial proliferation. During the summer 2005-spring 2006 microcystin-LR survey in Vojvodina, the toxin was permanently present in all examined ecosystems and the highest value of 362.68 μgL-1 was detected in Ludoš Lake. The part of Central Serbia is very problematic for ground water supply. For that reason more than 20 reservoirs serve as drinking water suppliers. Significant and persistent cyanobacterial blooms have been recognized in 9 of them. Samples for cyanotoxin analyses were taken during and after blooms in Ćelije Reservoir and in drinking water in Kruševac town 2 days later. Concentration of microcystin-LR was 650 μgL-1 in the reservoir while the tap water contained 2.5μgL-1.