Mar 7, 2014

Relative effects of climate change and wildfires on stream temperatures: a simulation modeling approach in a Rocky Mountain watershed

Lisa Holsinger, Robert E. Keane, Daniel J. Isaak, Lisa Eby, Michael K. Young
Climatic Change
  • States that freshwater ecosystems are warming globally from the direct effects of climate change on air temperature and hydrology and the indirect effects on near-stream vegetation
  • Holds that vegetative change may be especially rapid in fire-prone landscapes, causing significant local stream temperature increases
  • Links a spatially explicit landscape fire and vegetation model (FireBGCv2) to an empirical regression equation that predicted daily stream temperatures to explore how climate change and its impacts on fire might affect stream thermal conditions across a partially forested, mountainous landscape in the western U.S.
  • Uses the model to understand the roles that wildfire and management actions such as fuel reduction and fire suppression could play in mitigating stream thermal responses to climate change
  • Results indicate that air temperature increases associated with future climates could account for a much larger proportion of stream temperature increases (as much as 90 % at a basin scale) than wildfire
  • Finds, however, at finer spatial and temporal scales stream temperatures were sensitive to wildfire
  • Concludes that although wildfires will continue to cause local, short-term effects on stream temperatures, managers of aquatic systems may need to find other solutions to cope with the larger impact from climate change on future stream warming that involves adapting to the increases while developing broad strategies for riparian vegetation restoration