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Streams (Rivers). Sci 6.1. Runoff:. H 2 0 that does not sink into ground Most ends up in streams. How much, depends on terrain + amount of precip. Assume same precipitation for both. Which place would have More runoff?. Assume same precipitation for both. Which place would have
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Streams (Rivers) Sci 6.1
Runoff: • H20 that does not sink into ground • Most ends up in streams
How much, depends on terrain + amount of precip. Assume same precipitation for both. Which place would have More runoff?
Assume same precipitation for both. Which place would have More runoff?
Assume same precipitation for both. Which place would have More runoff?
People can increase runoff by: • Removing vegetation (road building, bad farming, clear cutting)
Clear cut forest in Canada
Extra runoff can lead to: • Loss of top soil • Aquifers not being replenished (wells going dry) • Flooding downstream
Load: • Sediment carried by water • Faster moving water carries more load
3 main types of load: • Dissolved: minerals like NaCl • Suspended: silt, clay (makes water look muddy) • Bed: sand, gravel Dissolved Suspended Bed
Types of streams: • Meandering streams: on low slopes, fine sediment
Cut bank: where sediment is carried away in fast water slow fast Draw and label fast slow slow fast
Drainage basin/Watershed: • area drained by a stream
Divide: • separates basins • Ex.: Rocky Mnts. called Continental Divide
Tributary: • smaller stream that empties into a larger one
Canyon formation: • River cuts down as land is uplifted
Uplift of the Colorado Plateaus forced rivers to cut down faster
Stream Deposition: produces produces erosion load deposition
Delta: • Sediment deposition when stream reaches its base level
Alluvial fan: • deposition when a stream flattens out
Stream discharge: • Volume of water flowing in m3/s (or cfm)
Floodplain: • Land next to stream that floods periodically
1. Levees: • ridges (natural or artificial ) that contain a stream