Iron Limitation in a Eutrophic Lake

Abstract

<p>Microorganisms need a combination of nutrients and trace metals in order for primary production to occur. The iron (Fe) hypothesis proposed that Fe is a limiting nutrient in the Pacific and Southern Oceans, and since the nutrients required by marine and freshwater microbes are the same, then Fe maybe a limiting nutrient in freshwater systems. Past research in freshwater systems has focused on phosphorous (P) and nitrogen (N) limitation. Recent studies done in Lake Erie, have suggested that it maybe a colimitation of P, N, and/or Fe that limits microbial activity. Nutrients and chlorophyll concentration were collected at Crystal Lake in Clark Count, OH in order to determine nutrient limitation throughout 2009-2010. Upcoming incubation experiments in spring 2010 will be conducted to determine the limiting nutrient or nutrients for the chlorophyll maximum that occurs at a depth of six to seven meters. Examination of the N, P, and Fe nutrients profiles at the lake have shown decreases in nutrient concentrations near the maximum chlorophyll concentration for the months of May, June, and August 2009.</p><p>This presentation occurred at the Wright State University Campus-Wide Celebration of Research, Scholarship and Creative Activities on April 16, 2010</p>