SS4.11 Water and Society - Science and Management in a Social and Economic Context
Date: Thursday, June 13, 2002
Time: 10:30:00 AM
Location: Sidney
 
Barlow-Busch, L, , Department of Biology, University of Waterloo, Waterloo, Canada, barlowbusch@sympatico.ca
Baulch, H, M, Department of Biology, University of Waterloo, Waterloo, Canada, hbaulch@ualberta.ca
TaylorWD, Department of Biology, University of Waterloo, Waterloo, Canada, wdtaylor@sciborg.uwaterloo.ca
 
PHOSPHATE UPTAKE AND REGENERATION BY SESTON AND EPILITHON IN THE EUTROPHIC GRAND RIVER, ONTARIO.
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Gross uptake of phosphate uptake by seston and epilithon was measured using 33PO4 as a tracer in the eutrophic Grand River in southern Ontario during the summer for 3 seasons. Uptake of phosphate by epilithon was measured using ceramic tiles incubated in the river for at least 6 weeks. Epilithon contributed much more to gross PO4 uptake than seston on an areal basis throughout the season, although on a mass basis the two compartments were more similar. Uptake rates for both seston and epilithon were highly variable; increased discharge was associated with increased phosphate concentrations and uptake velocities for the epilithon. Seston uptake varied with biomass. Variation also occurred within a day, although there was not a consistent daily pattern. Estimates of net uptake of PO4 by epilithon and seston were generally lower than estimates of gross uptake, indicating that phosphate regeneration was also occurring, particularly in the seston.