Wildfires transform and transport large amounts of organic carbon across landscapes at regional to continental and even global scales. The burning of vegetation and soil organic matter, followed by increased runoff of water and erosion, can have big effects on lakes. In addition, smoke plumes from wildfires may even influence lakes much farther away indirectly through what are called teleconnections. The 2013 Rim Fire was the third largest fire ever in California and presents an opportunity to examine these different types of movements of carbon and their impacts on lakes. This project rallies a team of experts from across the country to apply advanced optical and acoustic technology in order to examine the responses of lakes in the Sierra Nevada Mountains to changes in the quality and quantity of dissolved organic carbon (that colors water) and the consequences for the biology of the lakes. Two main questions are: What characteristics of lakes respond to changes in organic matter due to fires within their watersheds, and can such responses also be detected in lakes in distant watersheds through teleconnections? To address these questions, eight larger lakes and a suite of smaller lakes will be sampled over one year. The watersheds of two of the larger lakes have been extensively burned and influenced by smoke plumes from the Rim Fire. Three other larger and several smaller lakes are located about 150 miles north of the Rim Fire itself, but were still under the smoke plume from the fire. Finally, three lakes are outside of both the smoke and burn areas and will serve as control sites. Intensive sampling of the lakes themselves, data from satellite remote sensing, and detailed chemical analyses will be used to determine the exposure of all the lakes to either fire in the watersheds or just the smoke, as well as the effects on lake ecology.
This project will provide support for two postdoctoral fellows and three graduate students, who will study various aspects about tracing the flow of carbon from the land and air into and through lakes. Collaborations will enable the exchange of information between the research team and managers of the San Francisco water supply and reservoirs, as well as the general public. Other outreach opportunities will happen through collaborations with the Tahoe Environmental Research Center.
