File:Hood 2022 large wood distribution--MS.pdf

Large wood influences river geomorphology and ecology, so similar function is presumed in estuarine tidal channels. Consequently, restoration ecologists and engineers often recommend large wood supplementation for tidal marsh restoration, but there is no guidance on how much large wood is appropriate or where it should be located. GIS analysis of high-resolution aerial photos was used to map the distribution of individual tree logs greater than 2-m length in reference tidal marshes of eight Puget Sound river deltas. Statistical analysis showed that distributary networks, channel size, marsh size, fetch, topography, and woody vegetation affect large wood distribution on the marsh surface and in tidal channels. Large wood densities were 28 to 50 times lower in Puget Sound tidal channels than in Western Washington streams. These results provide an initial foundation for further studies on the ecological and geomorphological significance of large wood in tidal marshes, and some initial guidance to engineers and planners for large wood placement in marsh restoration projects.