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The use of outdoor freshwater pond microcosms. III. Responses of phytoplankton and periphyton to pyridaben

January 1, 2001

An outdoor freshwater microcosm study was conducted in which pyridaben, an insecticide-miticide, was directly applied to water to determine its biological effects on phytoplankton and periphyton. Twenty-four microcosms (24 m3 each) were monitored for 11 months, then four treatments of pyridaben were applied two times at three concentrations (0.34, 34.0 ??g/L), including an untreated control. The succession of algal groups observed and the major genera found in microcosms during the baseline phase of the study were typical of oligo-mesotrophic systems in Florida. Following application of pyridaben, the most remarkable effect was a positive correlation of phytoplankton abundance with pyridaben concentrations in water; indicating increased abundance as a result of exposure. Both Chlorophyta and Pyrrophyta exhibited a significant increase (p=0.05) in population abundance at 3.4 and 34.0 ??g/L pyridaben. Chrysophyta also elicited a trend of increased abundance at 34.0 ??g/L, although the effect was not significant. The effects on phytoplankton populations were associated with the decline of zooplankton populations as a result of a direct effect of pyridaben exposure. There were no effects of pyridaben on periphyton communities or on functional endpoints. ?? 2001 by John Wiley & Sons, Inc.

Publication Year 2001
Title The use of outdoor freshwater pond microcosms. III. Responses of phytoplankton and periphyton to pyridaben
DOI 10.1002/1522-7278(2001)16:1<96::AID-TOX110>3.0.CO;2-U
Authors R. M. Ross, W. F. Krise, Lori A. Redell, R. M. Bennett
Publication Type Article
Publication Subtype Journal Article
Series Title Environmental Toxicology
Index ID 70023528
Record Source USGS Publications Warehouse