Water Resources Research Act Program

Principal Investigators: John Peckenham

Abstract: Phosphorus (P) is often the limiting macronutrient in freshwater ecosystems. Eutrophication is a problem affecting many Maine lakes, especially in the Belgrade Lakes region. Bjorn is focusing his dissertation on P cycling between the sediment and water column of Salmon and Lovejoy ponds. He is using a passive sampling technique involving hydrogels to measure the P porewater concentration gradients in both ponds. Each pond develops large P concentration gradients in the hypolimnion during the summer stratification period. Preceding the release of P from the sediment to the water column, Bjorn’s hypothesis is the P porewater concentration depth profiles change dramatically and characteristically in each pond based on sediment properties. He is measuring the porewater in both ponds at four times during the winter, spring and summer. Based on his literature search, this will be the first time P porewater profiles will be examined temporally using hydrogel technology. This research will augment his knowledge of these systems and provide the data needed to complete the final chapter of his dissertation.