GEOG 372 Lecture Notes - Lecture 14: Salmonidae, Hydroelectricity, Sediment Transport
3 Sep 2016
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Document Summary
Natural erosion off of the slopes of mountains. Erosion zone at high altitudes with steep slope and less vegetation. Debris transport high in mountains is gravity-driven mass movement with no sorting. Slope reduction, sediment storage, banks stabilization, energy breaking effects. Downstream- wood dikes to increase friction and retain soil, floodplain tree planting. Debris flow control- widening and slope reduction of the deposition area. Sediment size (degradation if smaller, aggradation if larger) Stream slope (degradation if steeper, aggradation if flatter) Relationships between river discharge and bed load transport. Key element for channel morphology (shape, stability and evolution) Flood recurrence increased, groundwater table variability, pollution, water quality. Degradation coarsening of channel bed (spawning habitat changes) Aggradation silting-up of channel bed (changes to benthic invert communities and entombment/choking of salmonid embyros) Slope decreases downstream, while q, w, d and v tend to increase to varying degree. Q increases the most, followed by w, then d, then v.
