Rivers Flashcards
Describe the upper course of a river
Narrow, steep - sided due to vertical erosion as well as weathering
Transporting larger boulders due to high energy
Waterfalls, interlocking spurs, gorges
Describe the middle course of a river
Wider valley floor due to lateral erosion, gentle slope sides
Meanders, ox bow lakes, levees, floodplains
Describe the lower course of a river
Wide, flat valley floor,wide floodplain, meandering river
Low energy, small sediment
Meanders, ox - bow lakes, levees, floodplains
Hydraulic Action
The power of the flowing water erodes the rivers banks and bed. Usually at the base of waterfalls or on the outside of meanders
Abrasion
Scraping of sandpapering of a rivers bed or banks by rock particles carried by the river
Attrition
The gradual rounding and smoothing of rock particles as they knock/rub against each other in the river
Solution
Dissolving of soluble chemicals in the water, particularly affecting limestone and chalk
Traction
Large particles rolled along the river bed by the force of the water
Saltation
A bouncing or hopping motion by particles to heavy to be suspended
Suspension
Particles suspended within the water
Solution
Chemicals dissolved in the water
Example of a river valley in the UK to identify its major landforms of erosion and deposition
Physical factors affecting flood risk
Precipitation, geology, relief
Human factors affecting flood risk
Climate change, deforestation, land use
Hard engineering strategies to reduce flood risk
Dams, reservoirs, straightening, embankments, flood relief channels
