The Effects of a Sublethal Dose of Copper Sulfate on the Colonization Rate of Freshwater Protozoan Communities

Abstract

Whether a sublethal dose of CuCO4 would affect the colonization rate of freshwater protozoan [flagellate and ciliate] communities established on polyurethane foam units, and whether a correlation exists between the length of initial colonization of an artificial substrate epicenter in the lake and the extent of the toxicant''s effects on the colonization process in the laboratory are studied. Observed colonization rates for the systems under stress were compared to those of the control systems at the same stage of community development. A sublethal dose of CuSO4 significantly decreased the colonization rate of both the mature and immature communities (P < 0.05); the effects were greater on the immature systems.