kalade hukkumine
kalade järsk massiline suremine hapnikupuuduse, mürgiste ainete sisalduse suurenemise vm ebasoodsate keskkonnatingimuste tõttu, the death of a number of fish in a locality as a result of inadequate DO, excessive rate of temperature change, or the presence of a chemical at acutely toxic concentrations, durch Sauerstoffmangel bei starker Eutrophierung von Gewässern verursachtes Massensterben von Fischen