Differential responses by stream and riparian biodiversity to in-stream restoration of forestry-impacted streams

1. Forestry can have detrimental impacts on stream ecosystems, particularly via excessive sedimentation. A key challenge to stream management is therefore to identify the best restoration practices to mitigate the harmful impacts of fine sediments on stream biodiversity and ecosystem functioning. 2. We studied the effects of restoration of sediment-impacted headwater streams on the habitat structure, hydrologic retention, biodiversity (microbes, bryophytes, benthic macroinvertebrates, riparian plants) and ecosystem functions (periphyton accrual rate and leaf breakdown) by comparing four treatments: wood-restored, boulder-restored, impacted (by fine sediments) and near-natural streams. The restored streams were sampled three to seven years post restoration. Restoration by wooden or boulder structures aimed to reduce deposited sediments and increase channel heterogeneity and hydraulic retention. 3. Wooden structures were ineffective in removing fine bed sediments and did not induce posi...