Contemporary monitoring alone is not always sufficient to answer important management questions, so we aim to put modern conditions in a longer-term context. Paleolimnology uses fossil materials in aquatic sediments to infer past conditions and uncover trends in environmental quality. These retrospective data are needed to distinguish natural from human trends, and to reveal the causes and magnitudes of environmental insults that inform management matters regarding climate change, pollution and invasive species.

The cornerstone of many of these studies has been the use of diatoms, known powerful indicators of environmental change. Diatom algae have been calibrated to nutrients, and a diatom-based models are used in paleolimnological investigations to reconstruct its trophic history, such as that for the St. Louis River Estuary. Investigations are continuing to describe the anthropogenic history of degradation and remediation so that we can address the many environmental issues that require long-term data in order to make remedial decisions.

Two instructional videos are available below on paleolimnology: