Understanding the Role of Sediment Waves and Channel Conditions Over Time and Space
Lisle TE. 1997. Understanding the Role of Sediment Waves and Channel Conditions Over Time and Space. Pages 57-67. In Proceedings of the Sixth Biennial Watershed Management Conference. University of California, Davis
Abstract: "Dynamic equilibrium in stream channels has traditionally been applied on the reach scale, where fluxes of water and sediment into a reach result in rapid but minor adjustments of channel dimensions, hydraulics or roughness (equilibrium), or aggradation and degradation (disequilibrium). Such an essentially one-dimensional spatial approach to sediment-channel interactions implicitly avoids a longstanding and difficult problem: how do large inputs of sediment travel through channel systems and thereby distributethe fluxes to which channels respond at any time scale? Not much is known about sediment waves because they aredifficult to observe and model and have highly variable behaviors. Passage of sediment waves may or may not be marked by (fynamic disequilibrium but, nevertheless, can have influences on aquatic and riparian ecosystems that should concern land managers. Rapidly propagating, high amplitude waves can cause measurable aggradation, degradation, and charmel instability. Probably more often, however, waves disperse rapidly, translate slowly, and coalesce, and thereby inflict long-term widespread effects on channels and associated ecosystems. Such adjustments may go undetected or fall within the domain of dynamic equilibrium."
- Type
- Conference Proceeding Paper
- Authors
- Lisle, Thomas
- Units
- REDW
- Keywords
- channel conditions, dynamic equilibrium, sediment movement