16 terms

Drainage Basins

STUDY
PLAY
Drainage basin
Area that supplies a river with its supply of water, this includes water found below the water table as well as soil water and any surface flow.
Evapotranspiration
The total output of water from the drainage basin directly back into the atmosphere from evaporation and transpiration
Evaporation
The process by which liquid water changes to a gas. This requires energy, provided by the sun and aided by wind.
Groundwater flow
The slow movement of water through underlying rocks
Infiltration
The downward movement of water from the surface into the soil
Overland flow
The tendency of water to flow horizontally across land surfaces when rainfall has exceeded the infiltration capacity of the soil and all surface stores are full
Interception storage
The precipitation that falls on the vegetation surfaces or human-made cover and is temporarily stored on these surfaces
Throughflow
The movement of water down slope through the subsoil under the influence of gravity
Run-off
All of the water that enters a river channel and eventually flows out of the drainage basin
Percolation
The downward movement of water within the rock under the soil surface. Rates vary depending on rock.
Water balance
The balance between inputs and outputs in a drainage basin
Stemflow
The proportion of precipitation intercepted by the canopy that reaches the ground by flowing down stems, stalks or tree bole.
Soil storage
The amount of water stored in the soil.
Vegetation storage
Most plants remove water from the soil and store it in the structure of a plant
Infiltration capacity
Is exceeded when rainfall intensity is greater than the infiltration rate
Channel Flow
Transfers of water within a river or stream