Predictive Modeling
Coeur d'Alene Tribe Large Wood Recruitment
In this study, we used spatially referenced survey data and spatially distributed models to characterize wood-loading potential and management effects reach-by-reach in four watersheds in Northern Idaho. Comparison of wood inventory data from our surveys with other regional studies indicate that the study basins currently meet or nearly meet what are considered reasonable targets for wood abundance in terms of number per unit length (all pieces > 5" diameter can provide habitat function, although larger pieces are more likely to function than smaller pieces). The graphs below show cumulative frequency distributions for wood abundance for study reaches within each basin, starting with estimated current conditions (data for surveyed reaches and extrapolated values for reaches not surveyed), and extending through 150 years under the no management scenario. Lake, Alder, and Benewah basins all contain some study reaches with non-forested riparian zones; for these reaches, modeled wood recruitment and subsequent wood abundance are zero. Where riparian zones are forested, much of the channel length already meets regionally established targets for wood loading (e.g., 15 pieces /100m; 8.5 m3/100m), and the proportion of channel length not meeting these targets decreases over time under a no-management scenario.
