DEM

Geological

Historical Riparian

Internet Map Server

Land Use/Cover

Stream Networks

The Port Gamble S'Klallam Tribe has proposed to produce comparative maps of the historical riparian land cover for the Hood Canal basin. This may be an important part of the low oxygen issue for Hood Canal. For instance, one change in the riparian zone has been the replacement of fir and cedar trees with red alder. Alder trees fix nitrogen from the soil, meaning that water flowing through an alder forest will have more nitrogen dissolved in it than water flowing through fir or cedar forests. Perhaps this is "fertilizing" the nutrient-starved marine algae in Hood Canal, leading to their overgrowth and eventual demise, which draws down oxygen concentrations. Is this significant in Hood Canal? Is it part of the problem?

The Port Gamble S'Klallam Tribe will produce the maps and then the results will be used by the HCDOP-IAM modelers to answer these questions. You can learn more about this historical riparian comparison by downloading their HCDOP-IAM study proposal here.