1.1 The drainage basin system Flashcards
In the drainage basin, what are the outputs?
evaporation, evapotranspiration, river discharge
What are the stores?
interception, soil water, surface water, ground water, channel storage
What are the flows?
above ground = throughfall, stemflow, overland flow, channel flow
below ground = infiltration, percolation, throughflow, ground water, baseflow
What is the hydrological cycle?
The way that water moves from the sea, through the air and back into the sea.
What is precipitation?
Water falling from the sky
What is interception?
The rain which is intercepted before it reaches the ground, usually by vegetation.
What is throughfall?
In a long rainstorm, leaves become saturated and water begins to drip on the ground.
What is stem flow?
Water moves from tree to ground flowing down the outside of the trunk.
What is runoff/overland flow?
When the soil is saturated and rain continues to fall, the rain will have surface run off.
What is discharge?
The amount of water flowing down a river at any one time
What is infiltration capacity?
How much water can be taken into the ground before the water begins to sit on the surface and not be absorbed
What is throughflow?
The flow of water through the ground rather than on top of the ground soil layer
What is percolation?
Water that flows down into the bedrock
What is baseflow?
Water flowing from ground water into lakes or rivers
What is groundwater?
Storage of water in the ground e.g. water in rocks
What is a water table?
Imaginary line which is where ground water is stored below and through flow is above level of saturation
What is evapotranspiration?
Moisture from transpiration and evaporation put together in the atmosphere. Water evaporates from leaves etc. while trees transpire.
What is the guaging system?
Measures discharge
What is hydrostatic pressure?
Force exerted by groundwater flow against the rock above it until the water finds a crack and rises to the surface. Often basements flood upwards
What is porosity?
The percentage of void space in a rock, and how easy it is for liquid to pass through the material
What is permeability?
How much water the ground can absorb
What is an aquifer?
Underground store of water which fell as rain 1000s of years ago
What is surface storage?
Total volume of water held on Earth’s surface in lakes etc.
What is velocity?
Refers to speed (in a direction) at which a river is flowing
What is a regime?
Term given to the difference in discharge of a river throughout the year
What is antecedent moisture?
Amount of moisture in the soil before rainfall
