geography

• Hydraulic impact
• Attrition


  Collision of rock fragments suspended in water
• Abrasion


  Grinding of rock fragments carried by a river against the bed and banks of that river. This action causes the river channel to widen and deepen. This grinding is most powerful during a flood
• Solution


  Process by which river water dissolves minerals in rocks and chemically reacts with soluble minerals
• Hydraulic action


  Form of mechanical weathering caused by the force of moving water, which can force air into cracks and undermine or erode the outside of a river bank, especially in waterfalls
• Transportation

  The movement of material by rivers, which need energy to transport material and levels of energy change from the source to the mouth of the river
• Deposition


  The laying down of material previously transported by a river when the velocity of the river is reduced, causing the river to drop its load
• The river has more energy to transport material by Suspension
• This material Beats the Queside bank by Corros fabrauts
• The bank will be undercut, Calinese and retreut leaving a Small River cliff
• On the inside bend there is an increase in friction and a decrease in velocity
• Inside bend Characteristics

  • Reduction in friction
  • Increase in velocity
  • Increase in erosion
• Outside bend Characteristics

  • Fastest flow
  • Reach fat
  • Ba lum
• Reduction in friction, increase in velocity, increase in cangy, increase in erosion when bank is undercut
• Flood plains


  • The area of land on either side of a river which is flooded during times of flood
• At times of high discharge the river has a long way to transport material by Suspension
• Each time a river floods, a layer of sediment is deposited
• The coarsest/smallest drop first close to the bank to form a levee
• The fine material deposited on the floodplain increases the fertility of the soil
• Impacts of flooding on people and environment


  • People and animals can become homeless
  • Buildings can be damaged or destroyed
  • Crops can be lost
  • Positive - Replenishes drinking water
  • Provides sediment
  • Fish benefit as they feed on insects washed in
  • Can encourage innovative solutions
• Wild animals may drown or lose their habitat
• Flood management includes hard engineering methods and soft engineering methods
• Hard engineering methods are not sustainable
• Soft engineering methods

  • Afforestation
  • Land use Zoning
  • Wash lands
• The hydrological cycle is the continual transfer of water between the land, sea, and atmosphere
• Definitions related to rivers

  • Drainage Basin: An area of land drained by a river and all its tributaries
  • Tributary: A stream which flows into a larger river
  • Watershed: Boundary between drainage basins, often a ridge or high bank
  • River Channel: Where the tributaries meet
  • Source: The starting point of a river
  • Confluence: The point where two rivers meet
  • Mouth: The end of a river where it flows into the sea or lake
• Precipitation: Any form of water falling from the sky
• Surface runoff: Water moving over the land surface
• Through-flow: Water flowing through the soil
• Percolation: Water sinking down through the soil
• Groundwater flow: Water flowing slowly underground
• River discharge: Water flowing out early in the river to the sea or lake
• Evaporation: The transfer of water from the sea to the air
• Vapour: Water in the form of gas
• Long Profiles of rivers may be directed upstream or downstream
• Long Profiles are concave in shape but different rock types make them irregular
• Bradshaw model: Shows how characteristics of rivers change along their course
• Interlocking Spurs: Energy used to transport large boulders along the river bed through vertical erosion
• River downstream towards the mouth flows over flatter land and develops large bends called meanders
• Lateral erosion occurs in the middle course of the river