Disturbances in Steep, Forested Basins.

Geomorphic response to watershed disturbances commonly results in alterations of landforms. Subsequent geomorphic recovery is dependent on the ability of flows to entrain, transport, and organize inorganic and organic material on hillslopes and in channels. This research analyzed changes in sediment production, channel structure, and channel organization following disturbances in steep, forested terrain. Examining a range of channel environments following sediment pulses permitted the development of a conceptual model predicting trajectories of channel change. Extensive road construction and timber harvest on steep, forested hillslopes in the Redwood Creek basin, north coastal California, caused increased sediment yields to streams. This study examined the effectiveness of erosion control efforts on these disturbed hillslopes following a 12-year storm. The erosional response of treated logging roads was strongly related to their geomorphic setting: roads on gentle, convex, upper hillslopes contributed much less sediment than roads on steep, lower hillslopes (10 and 550 m3 of sediment/kilometer of treated road, respectively). Since 1980, 300 km of Redacted for Privac