Ecological–microbiological studies of lake Beloe in winter and spring with the use of innovation test-systems

Chlorophyll a concentration, the total abundance of bacteria, the number of bacterial cells with active metabolism, and the abundance of saprotrophic bacteria were studied in the surface and bottom water layers of Lake Beloe in winter and spring 2015–2016. The abundance of sanitary-indicator microorganisms was determined for the first time with the use of Petrifilm test-systems (3MTM Petrifilm™). In most cases, Lake Beloe water in spring and winter was found to correspond to eutrophic level (in terms of chlorophyll a concentration in water) and polysaprobic status (in terms of microbiological indices). By its sanitary-microbiological characteristics, the lake is clear—the values of the total microbial count, determined with the use of test-systems 3M™ Petrifilm™ Aqua (AQHC), were <1000 CFU/mL, and the abundance of coliform bacteria, determined with the use of test-systems 3M™ Petrifilm™ Aqua (AQСC), varied from 20 to 135 CFU/100 mL. Coliform bacteria were mostly found in the bottom water layer. It was shown that, in the organization of ecological–microbiological studies, special attention is to be paid to the bottom horizons of water bodies.