Fire is a major form of disturbance that influences the composition, structure, and distribution of vegetation. Fire frequency is affected by climate, and as climates change, so does the way that fires shape and maintain spatial patterns of vegetation. Past changes in fire frequency have been shown to accelerate and amplify effects of climate change, thereby producing more rapid shifts in vegetation composition and distribution than would have otherwise occurred. The specific links among long-term changes in climate, vegetation, and fire regimes are not well understood, however. This doctoral dissertation research project will analyze charcoal, magnetic susceptibility, and pollen from sediment cores taken from lakes in three different biogeographic provinces in Yellowstone National Park in order to reconstruct the fire history of the area over the last 14,000 years. These analyses will elucidate fire regimes for different kinds of vegetation and will address the role of regional climatic change as an influence on fire frequency. This project will provide information and insights of value from a number of different perspectives. Although focusing on change in Yellowstone National Park, the data gathered through analyses in this project will complement data gathered from numerous other sites in the northwestern U.S. thereby advancing knowledge of regional climate and vegetation change since the last glacial advance. The study also will contribute to deeper understandings of the complex involvement of fires in climatic and vegetational processes. This type of knowledge may have increasingly significant utility for resource managers in the park and in other environments if climatic changes forecast for future decades occur. As a doctoral dissertation improvement award, this award also will provide support to enable a promising student to establish a strong independent research career.
