Abstract
The research underway focuses on the vegetational history of the Greater Yellowstone Ecosystem and the response of plant communities to environmental changes of varying intensity and duration. Four studies are in progress and at different stages of completion. In two investigations, processes operating on time scales of centuries and millennia are being studied to reconstruct the long-term environmental changes of the last 14,000 years. In a third study, a time scale of decades or less helps to clarify the nature of Yellowstone's northern range prior to and since the establishment of the Park. Finally, focusing on a time scale of years or less, we are investigating the sedimentary inputs in the aftermath of the 1988 fires to determine the processes by which lake sediments record fire events. An examination of the paleoecologic record on these different time scales provides information on the relative sensitivity of plant communities and lake systems to long-term and short-term disturbances, and adds to our knowledge of the postglacial history of the northern Rocky Mountains.