M-B Supply and Transport Limitations
Montgomery and Buffington classification is often simplified to consider the following three levels of Stream type and function:
Transport limited Streams are with sediment loads that exceed hydraulic capacity, and hence Deposition may be prevalent. Supply limited Streams have hydraulic capacity beyond supply, and hence scour and Erosion may be prevalent. The steeper channels (step-pool, cascade, and possibly bedrock) transmit high sediment loads and maintain their morphology, while flatter channels (braided, regime, riffle-pool) experience morphological adjustment with increased sediment load.
- First - determine if Valley type is Colluvial, Alluvial, or Bedrock
- Second - determine if channel is Colluvial, Bedrock, or Alluvial. If Alluvial, then determine type as Braided, Regime, Pool-Riffle, Plane-Bed, Step-Pool, or Cascade
- Third - interpret channel response to sediment on spectrum of transport limited (colluvial) to supply limited.
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