River Landscapes Flashcards
River Landforms
V-shaped valleys
Vertical erosion is dominant in the upper course of the river
This cuts down into the river bed and deepens the river channel
Weathering and mass movement leads to material from the valley sidWith distance downstream the size of the meanders increase
The erosion on outside bends can eventually lead to the formation of a meander neck
At a time of the flood, the river may cut through the neck of the meander forming a straighter course for the water
The flow of water at entry and exit from the meander will be slower, leading to deposition
The meander becomes cut off from the main river channel, forming an oxbow lakees collapsing into the river forming a steep v-shaped valley
Vertical erosion is dominant in the upper course of the river
This cuts down into the river bed and deepens the river channel
Weathering and mass movement leads to material from the valley sides collapsing into the river forming a steep v-shaped valley
Interlocking spurs
Meanders
Ox bow lakes
With distance downstream the size of the meanders increase
The erosion on outside bends can eventually lead to the formation of a meander neck
At a time of the flood, the river may cut through the neck of the meander forming a straighter course for the water
The flow of water at entry and exit from the meander will be slower, leading to deposition
The meander becomes cut off from the main river channel, forming an oxbow lake
Hard engineering flood management
Dams and Reservoirs
Controls the river flow by blocking the river and letting water in a controlled way. This creates a reservoir behind the dam
Straightening Channels
Straightening the river channel by removing meanders
Soft engineering
Afforestation
Planting of trees to increase interception and infiltration. Trees also use up large quantities of water
Flood warnings
Monitoring of rivers to provide people with warnings when flooding may occur
River restoration- Restores the river to its natural state with meanders and wetland areas
