Impact of physical factors

• Climate


  • Mainly impacts on the inputs and outputs
  • Climate has a role in influencing the type and amount of precipitation overall and the amount of evaporation (i.e. the major inputs and outputs)
  • Climate also has an impact on vegetation type
• ​Soils


  • Largely affect the relative importance of the different flows within the system (of these flows perhaps the most important is surface runoff)
  • Soils determine the amount of infiltration and throughflow, and indirectly, the type of vegetation
• Geology


  • Largely affects the relative importance of the different flows within the system (of these flows perhaps the most important is surface runoff)
  • Geology can impact on subsurface processes such as percolation and groundwater flow (and, therefore, on aquifers)
  • Indirectly, geology affects soil formation.
• Relief


  • ​Largely affects the relative importance of the different flows within the system (of these flows perhaps the most important is surface runoff)
  • Relief can impact on the amount of precipitation. 
  • Slopes can affect the amount of runoff. 
• Vegetation


  • Largely affects the relative importance of the different flows within the system (of these flows perhaps the most important is surface runoff)
  • The presence or absence of vegetation has a major impact on the amount of interception, infiltration and occurrence of overland flow, as well as on transpiration rates.