how can coastal landscapes be viewed as systems?

  • Created by: beaw18
  • Created on: 24-04-19 12:13

introduction

  • system - a set of interrelated objects comprising of components (stores) and processes (links)
  • coastal landscape systems store and transfer energy and material on varying time scales 
  • energy may be kinetic (movement), thermal (heat), potential (energy due to position)
  • material is typically sediment - found on beaches, estuaries, nearshore zones (shallow water area at beach)
1 of 4

open system

  • coastal landscapes recognised as open systems - energy and matter can be transfered from neighbouring systems as an input 
  • can also be transfered in neighbouring systems as an output
  • coastal landcape has: 
    • inputs: kinetic energy from wind and waves, thermal energy from sun, potential energy from position of material on slopes, marine deposition weathering and mass movement from cliffs 
    • outputs: marine and wind erosion of beaches and rock surfaces, evaporation 
    • throughputs: stores; beach and near shore sediment accumulations, flows; transfers of sediment such as longshore drift 
2 of 4

system feedback in coastal landscapes

  • equilibrium - when a systems inputs and outputs are equal
    • could occur when rates of sediment added to beach are equal to sediment removed from beach 
  • dynamic equilibrium - inputs and outputs are no longer equal, and so the system undergoes self-regulation to restore equilibrium 
    • this is an example of negative feedback - decreases amount of change by reducing some of the inputs 
3 of 4

sediment cells

  • sediment cell - stretch of coastline where sediment movement is self contained 
  • regarded as a closed system - no sediment moves from one cell to another
    • unlikely that cells are completely closed, as variations in wind directions and global currents will cause a little movement of sediment between cells  
  • 11 sediment cells around coast of England and Wales
    • examples include St Abbs Head, Flamborough Head and Land's end 
  • boundaries determined by topography (shape of the landscape) and shape of coastline
    • large physical features act as natural barriers, that prevent the transfer of sediment to other cells
  •  sub-cells also exist in major cells 
4 of 4

Comments

No comments have yet been made

Similar Geography resources:

See all Geography resources »See all Coastal environments resources »