FORSTER, C. & K. J. WITTMANN, 2002: Temporal performance of the "Dynamic Daphnia Monitor" using Daphnia magna Strauß under diverse toxic loads. In N. FLEISCHMANN, G. LANGERGRABER & R. HABERL (Eds.): Proceedings International IWA Conference on Automation in Water Quality Monitoring. AutMoNet 2002; Vienna, Austria, May 21-22, 2002. University of Agricultural Sciences (BOKU), Vienna: 401-404.
The temporal patterns of swimming activity of Daphnia magna Strauß were examined under the influence of certain toxins in water. The reactions were monitored with the Dynamic Daphnia-Test-device under controlled conditions of temperature, light, and nutrition. Aqueous solutions of the heavy metal cadmium and the insecticide Lindane were tested. For the herbicide Atrazine, aqueous solutions with and without 0.5 ethanol were used. The principal temporal patterns of reaction did not vary greatly between the various toxins. Low concentrations slightly above the lower threshold level for any significant reaction induced weak hyperactivity in a number of tests, whereas higher doses caused strong or in part very strong hypoactivity with or without a preceding phase of hyperactivity. The most striking results occurred with Lindane, in accordance with previous findings that daphnids are strongly susceptible to low doses of insecticides. Waves of rising and declining concentrations of Atrazine were used to simulate pulses of toxic impact on rivers; this resulted in threshold limits for induction of significant changes in swimming activity that differed from those in a longer-lasting, more continuous exposure to the toxin. These results can help improve the interpretation of the monitor recordings and establish Daphnia magna as an appropriate test organism for continuous monitoring of low concentrations of toxic substances in water.
biosensors; alarm systems; surveillanc; quality assessment; cadmium; Lindane; Atrazine
Daphnia magna