Aqa as Geography Uni 1
Rivers, Flood and Management
The draining basin hydrological cycle:
The drainage basin is the area of land that is drained by a river and its tributaries. Also; the catchment area from which a river system obtains its water.
Drainage basin largely ‘closed’ system- watershed – boundary of a water basin- generally follows a ridge of high land.
Movement of water in a drainage basin-Drainage Basin Hydrological Cycle- open system with inputs and outputs
LOOK AT PAGE 9 IN NEW TEXTBOOK FOR DIAGRAM
Definitions:
Evaporation-Process by which liquid water is transformed into water vapour.
Evapotranspiration-The total amount of moisture removed by evaporation and transpiration from a vegetated land surface.
Base Flow-Slow transfer of water through rocks.
Infiltration-The passage of water into the soil. Takes place relatively quick at the beginning of a storm but as the soil becomes saturated infiltration rates fall rapidly.
Interception-When vegetation intercepts some precipitation on its way to the ground. Water is then lost back to atmosphere by evapotranspiration. Plants also use some water for growth; vegetation reduces and slows down waster transfer to river.
Percolation-The deeper transfer of water into permeable rock under the soil surface.
Precipitation-Water in any form that falls from the atmosphere onto the surface of the Earth.
Overland Flow-Rapid transfer of waster over surface of the ground- most likely to occur during periods of very heavy rainfall or when soil has become completely saturated.
Through Flow-Downhill transfer of water through soil layer to the river. Particularly effective when impermeable rocks prevent percolation.
Water Balance:
Water balance helps give understanding of unique hydrological characteristics of an individual drainage basin. Also known as the balance between inputs and outputs.
Precipitation (P) = Streamflow (Q) + Evapotranspiration (E) +/- Changes in storage (S)
P=Q + E +/- S
Factors affecting
The draining basin hydrological cycle:
The drainage basin is the area of land that is drained by a river and its tributaries. Also; the catchment area from which a river system obtains its water.
Drainage basin largely ‘closed’ system- watershed – boundary of a water basin- generally follows a ridge of high land.
Movement of water in a drainage basin-Drainage Basin Hydrological Cycle- open system with inputs and outputs
LOOK AT PAGE 9 IN NEW TEXTBOOK FOR DIAGRAM
Definitions:
Evaporation-Process by which liquid water is transformed into water vapour.
Evapotranspiration-The total amount of moisture removed by evaporation and transpiration from a vegetated land surface.
Base Flow-Slow transfer of water through rocks.
Infiltration-The passage of water into the soil. Takes place relatively quick at the beginning of a storm but as the soil becomes saturated infiltration rates fall rapidly.
Interception-When vegetation intercepts some precipitation on its way to the ground. Water is then lost back to atmosphere by evapotranspiration. Plants also use some water for growth; vegetation reduces and slows down waster transfer to river.
Percolation-The deeper transfer of water into permeable rock under the soil surface.
Precipitation-Water in any form that falls from the atmosphere onto the surface of the Earth.
Overland Flow-Rapid transfer of waster over surface of the ground- most likely to occur during periods of very heavy rainfall or when soil has become completely saturated.
Through Flow-Downhill transfer of water through soil layer to the river. Particularly effective when impermeable rocks prevent percolation.
Water Balance:
Water balance helps give understanding of unique hydrological characteristics of an individual drainage basin. Also known as the balance between inputs and outputs.
Precipitation (P) = Streamflow (Q) + Evapotranspiration (E) +/- Changes in storage (S)
P=Q + E +/- S
Factors affecting