Presenter/s: Stephen Bennett
Symposium Session: 2024 - 07 Key Results from Intensively Monitored Watersheds: Incorporating Lessons into Restoration Programs and Project Design
Topics covered: adaptive management and monitoring, fish-salmon, fish-steelhead, and lessons learned
ABSTRACT
Growing awareness among stream restoration practitioners that biology (e.g., beaver and wood) can govern stream morphology and evolution, has resulted in an explosion of interest and implementation of low-tech process-based stream restoration techniques (e.g., beaver dam analogues). However, these techniques may not produce the expected outcomes if the appropriate sequence of processes have not been identified, or if expectations are not based on an understanding of the geomorphic and biological context that constrain what is possible. Therefore, clear examples of how to plan and implement low-tech restoration are needed, accompanied by effectiveness documentation. Results from a long-term experiment testing the effectiveness of post-assisted log structures (PALS) at increasing riverscape complexity and juvenile steelhead productivity will be presented. The experiment used an adaptive management framework to explicitly link restoration actions with specific, required processes to achieve increased geomorphic complexity and floodplain connection. Maintenance, wood movement, adjustments to restoration actions, disturbance, and time all played a role in increasing the frequency of bar, pool, and side-channel habitat which led to an increase in steelhead production (g/km/Season) and productivity (smolts) in treatment sections compared to control sections.