Stream Nutrient Responses to Forest Harvest and Disturbance: Lessons From Long-Term Research at USFS Experimental Forests
Event Website
http://www.nafew2009.org/
Start Date
6-22-2009 12:00 AM
End Date
6-25-2009 12:00 AM
Description
Both land management and natural disturbance can dramatically affect the water quality of headwater streams and downstream rivers. For decades, researchers have studied stream hydrology and solute chemistry in disturbed and undisturbed watersheds at Experimental Forests - a continental-scale research platform that spans gradients of precipitation, atmospheric deposition, nutrient limitation, biomes, topography, and soil types. To increase our understanding of water quality responses to disturbance, we examine: 1) How the short and long-term responses of stream nutrients to forest harvest and various disturbance types differ across North America; and 2) Which biotic and abiotic factors explain variability in the magnitude, timing and duration of stream solute responses within and among sites. Following whole catchment clearcutting, concentrations and fluxes of stream nitrate increased dramatically at most sites. However, the duration of elevated streamwater nitrogen varied from years to decades and appears to reflect the role of recovering vegetation on nutrient demand and turnover and spatial patterns of ecosystem nutrient limitation. Fire, beetle outbreak and hurricanes all stimulate nitrogen release associated with short-term changes in plant nutrient and water uptake and longer-term processes that influence changes in vegetation structure and recovery and watershed nutrient dynamics. Efforts to synthesize long-term watershed biogeochemistry research conducted at the Experimental Forest and Range network will advance understanding of the roles of management and disturbances on in-stream biotic communities and downstream water users.
Stream Nutrient Responses to Forest Harvest and Disturbance: Lessons From Long-Term Research at USFS Experimental Forests
Both land management and natural disturbance can dramatically affect the water quality of headwater streams and downstream rivers. For decades, researchers have studied stream hydrology and solute chemistry in disturbed and undisturbed watersheds at Experimental Forests - a continental-scale research platform that spans gradients of precipitation, atmospheric deposition, nutrient limitation, biomes, topography, and soil types. To increase our understanding of water quality responses to disturbance, we examine: 1) How the short and long-term responses of stream nutrients to forest harvest and various disturbance types differ across North America; and 2) Which biotic and abiotic factors explain variability in the magnitude, timing and duration of stream solute responses within and among sites. Following whole catchment clearcutting, concentrations and fluxes of stream nitrate increased dramatically at most sites. However, the duration of elevated streamwater nitrogen varied from years to decades and appears to reflect the role of recovering vegetation on nutrient demand and turnover and spatial patterns of ecosystem nutrient limitation. Fire, beetle outbreak and hurricanes all stimulate nitrogen release associated with short-term changes in plant nutrient and water uptake and longer-term processes that influence changes in vegetation structure and recovery and watershed nutrient dynamics. Efforts to synthesize long-term watershed biogeochemistry research conducted at the Experimental Forest and Range network will advance understanding of the roles of management and disturbances on in-stream biotic communities and downstream water users.
https://digitalcommons.usu.edu/nafecology/sessions/posters/3