SAPROBIEN SYSTEM

(Water Quality) A European system of classifying organisms according to their response to organic pollution in slow-moving streams. Classifications include: (1) Alpha-Mesaprobic Zone: Area of active decomposition, partly Aerobic, partly Anaerobic, in a stream heavily polluted with organic wastes; (2) Beta-Mesaprobic Zone: That reach of a stream that is moderately polluted with organic wastes; (3) Oligosaprobic Zone: That reach of a stream that is slightly polluted with organic wastes and contains the mineralized products of self-purification from organic pollution, but with none of the organic pollution remaining; (4) Polysaprobic Zone: That area of a grossly polluted stream that contains the complex organic wastes that are decomposing primarily by anaerobic processes.