River environments

• Transfers

  The movement of water between stores in the hydrological cycle
• Groundwater


  Water contained within the soil or underlying rocks, derived mainly from percolation of rainwater and meltwater
• Stores


  Features that receive, hold, and release water (RHR)
• Hydrological cycle


  The global movement of water between the air, land, and sea
• Aquifer


  Permeable rock capable of holding and transferring underground water
• Evapotranspiration is the combined process in which water moves from the earth’s surface into the atmosphere
• Open system

  A set of interrelated objects where there are both inputs and outputs
• Percolation is the downward movement of water from the soil to the rock beneath
• Permeable


  Allowing liquids or gases to pass through
• Flows


  Steady streams of movement from one point to another
• Storm hydrographs show the change in river discharge after a storm event
• Transfers within water cycle

  1. Evaporation

  2. Condensation

  3. Transpiration

  4. Evapotranspiration

  5. Precipitation

  6. Overland flow

  7. Infiltration

  8. Percolation

  9. Throughflow

  10. Groundwater flow
• Parts of a drainage basin include Source, Tributary, Confluence, Estuary, and Watershed
• Channel network is the collection of all the channels in a given drainage basin
• Infiltration is the process in which water on the ground surface enters the soil
• Lag time is the delay between peak rainfall and peak discharge
• Storm flow is the additional discharge of the river after a storm event
• Factors affecting river regimes include Temperature, Climate, and Precipitation
• Hydrograph is a graph showing the discharge of a river over a given period of time
• Outputs of drainage basins include the river’s discharge and water that evaporates and transpires from the basin and eventually lands in another drainage basin
• Drainage basin is an area that is drained by a river and its tributaries; it is an open system
• Groundwater flow is the underground transfer of water to rivers, lakes, and seas (water bodies)
• Abstraction is the removal of water from rivers, lakes, and from below the water table (R,L,BW)
• Reservoirs


  An area where water is collected and stored for human use
• Closed system


  A system that has no inputs or outputs
• Meltwater


  Water formed by the melting of snow and ice
• Interception


  The retention (holding) of water by plants and soil which is then evaporated and sent to the atmosphere or absorbed by vegetation
• Throughflow is when water moves slowly through the soil between the ground surface and the top of the groundwater store until it reaches a stream/river
• Overland flow occurs when precipitation hits the ground, moves due to gravity, and eventually reaches a water body
• River Discharge is the quantity of water flowing in a river channel at a particular location and time
• Dams are large structures built across a river to hold back a large body of water (reservoir) for human use
• Inputs of drainage basins include energy from the sun, precipitation, and water from tributary drainage basins
• Base flow is the ‘normal’ discharge in a river
• River regime is the seasonal changes of discharge in a river
• Climate - High temps

  More evaporation → reduce discharge
• Vegetation - Trees/plants


  Intercept and delay water reaching the ground → reduce overland flow → reduces discharge
• Rock type - Permeable rocks


  Slows delivery of water to river
• Land use - Turmac & concrete in urban areas


  Impermeable → speeds up run off and reduces lag time
• Deposition - The dropping off of material by river when it doesn’t have the energy to carry them
• Vertical erosion - Increases depth of river and is dominant in the upper course of the river