Spatial Distribution of Riparian Zone Coarse Woody Debris in a Managed Northern Temperate Watershed

Abstract

ABSTRACT Coarse woody debris is an important structural component of both terrestrial and aquatic ecosystems. We investigated coarse woody debris size-structure, decay class composition and distribution within the interface between second growth mixed conifer-hardwood forests and perennial streams in a catchment of the Lake Superior watershed on the Keweenaw Peninsula, Michigan. Down dead wood accumulation was nonlinearly distributed along transects perpendicular to streams and reached a peak between 30 and 50 m away from the wetted stream channels. Variability in the abundance of standing snags displayed a significant increase with distance. The coarse wood accumulations we observed were consistent with levels reported for upland, second-growth forests and were low compared to old-growth forest remnants in the region. Large (>40 cm diam) down dead wood will probably be the slowest pool to recover from logging and land clearing activities that occurred in the watershed prior to the turn of the 19th Centur...