Lately in the lake Sevan was discovered growth of Anabaena (Lat. Anabaena) blue-green algae. In the lake Sevan Anabaena blue-green alga was first recorded in the 40 s of the last century. The first algae bloom was recorded in 1964 and in various time was periodically repeated in different volumes. A large-scale algae bloom was observed in 2018. As to the experts several factors have contributed to the growth of blue-green algae. The wastewater flowing...