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Particle Transport and Movement. Transport of sediment involves 2 steps:Erosion and entrainment of sediment from the bedDowncurrent movementFollowed by:Settle out and deposition. Entrainment. Process involved in lifting resting grains from the bedThreshold of particle movementFunction of Cr
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1. Sediment Transport Stream Ecosystems
2. Particle Transport and Movement Transport of sediment involves 2 steps:
Erosion and entrainment of sediment from the bed
Downcurrent movement
Followed by:
Settle out and deposition
3. Entrainment Process involved in lifting resting grains from the bed
Threshold of particle movement
Function of Critical Boundary Shear Stress
4. Particle Entrainment Critical threshold for grain movement
Direct function of:
Boundary shear stress
Fluid viscosity
Particle size, shape, and density
Indirect function of:
Flow velocity
Varies as log of distance above bottom
5. Particle Entrainment F drag + F lift must overcome F gravity + F friction to initiate grain movement
6. Forces Initiating Grain Movement