Object & Deliverables
The primary goal of this project was to investigate the ecological links between natural disturbances in riparian forests and temporal changes in large woody debris (LWD), including the processes of log recruitment, persistence, decay, and transport in streams. Multiple lines of evidence were used to investigate lodgepole pine- and spruce-dominated forests surrounding streams in the Rocky Mountain foothills of western Alberta. Field surveys determined the abundance, quality, and function of logs in 56 different sizes that had been burned by fires at different times in the past: <5, 50, 100, and >150 years. A combination of data from permanent sample plots and tree-ring analysis of living and dead trees allowed for the reconstruction of forest histories and LWD dynamics. Several discoveries were revealed as a result. Specifically, these findings:
- Emphasized the importance of natural disturbances in riparian forests as a key driver of in-stream LWD dynamics.
- Illustrated that fire and harvesting impact LWD dynamics differently, providing opportunities for innovative silviculture.
- Confirmed the value of buffer zones surrounding streams, particularly as sources for LWD recruitment in harvested and burned landscapes.
- Provided ecosystem-specific baseline data to ensure long-term success of forest management and stream restoration through action and monitoring.
The complete findings of this project are contained in a report entitled “Temporal dynamics of Large Woody Debris in the Foothills of Alberta,” dated January 2011.