Sediment Phosphorus and Release Rates Daniel White Department of Environmental Science and Biology SUNY Brockport

27 August 2003 Two sediment cores collected from deepest part of the South Basin Sediment cores collected from the mouths of the following streams: –Cottonwood –Sand Point –North McMillan –Sutton Point –Long Point –Graywood

Also Collected Dredge samples collected from: –North Gully –Sand Point –Long Point –Graywood

Anoxic Release Rate Methods Nurnberg, G Prediction of Phosphorus Release Rates from Total and Reductant-Soluble Phosphorus in Anoxic Lake Sediments. Can. J. Fish. Aquat. Sci. v. 45, p Top of sediment core tube fitted with manifold Filled with anoxic lake water –Lake water purged with N 2 and Na 2 SO 3 Sample collected daily for 15 days –Soluble Reactive Phosphorus (SRP) –Dissolved Oxygen (DO) –pH

Anoxic Release Rate Results Avg. Release Rate: 4.1 mg P/m2/day

Sediment Phosphorus Methods Stream mouth and deep water cores dissected in 1 cm intervals Dried at 30ºC overnight 0.1 g of dry sediment was digested with nitric and sulfuric acid, filtered, neutralized, and diluted to 100 ml of volume Analyzed using ascorbic acid method on a Technicon II Autoanalyzer