A SHORT-TERM DIATOM-INFERRED HISTORY OF BEARTOOTH LAKE, WYOMING

Beartooth Lake, an alpine lake of glacial origin, is located in the Beartooth Mountains to the East of Yellowstone National Park at an elevation of 2,720 m. Beartooth Lake has a maximum water depth of 28 m. Like many alpine lakes in the Rocky Mountain region, Beartooth Lake has high clarity with a deep chlorophyll maximum. In this study, we explore preliminary fossil diatom assemblage data from a short surface sediment core collected in August of 2015 and measuring 34 cm. Because of the high transparency, the system is primarily dominated by benthic diatom species, despite the collection of the core from fairly deep water. The lake is a popular location for recreation and a campground is located along the southern shore. We targeted this site to determine whether anthropogenic activity has any influence on the recent part of the record. Potential impacts include the establishment of the area for recreational use, atmospheric nitrogen deposition, as well as climatological changes in recent centuries.