Earth Sciences Commons^™

The Role Of Logmat Biofilm In The Spirit Lake Ecosystem After The Eruption Of Mt. St. Helens, Emma Sevier

Summer Research

Spirit Lake, on the flanks of Mount St. Helens, was dramatically altered as a result of the eruption in 1980, and over the past 37 years the lake ecosystem has recovered in a rapidly evolving volcanic landscape. While Spirit Lake is similar in many ways to other alpine oligotrophic lakes, it is unique because approximately 20% of the lake’s surface remains covered with floating log mats from trees felled during the eruption. The undersides of the logs provide a substrate for biofilm (periphyton) that is primarily comprised of algae, diatoms, and cyanobacteria. Due to the sheer amount of log-based surface …