Drainage basins

Drainage basin

The area of land drained by a river and its tributary’s functioning as an open system where water is stored and flows between inputs,outputs and stores

Features of a drainage basin

Source,floodplain,watershed,mouth,tributary,confulence

Floodplain

Flat area alongside a river channel that is periodically flooded when the river overflows its banks

Conflulence

The point where two rivers meet

Inputs

Precipitation, which can vary and is influenced by climate and season

Stores

Interception storage

surface storage

vegitation storage

Groundwater storage

channel storage

soil water storage

Interception storage

Water temporarily held on a plant surface such as leaves after precipitation before it evaporates and touches the ground

Surface storage

Includes water in puddles

Soil water storage

Includes moisture in the storage

Vegitation storage

Water stored withing plants and trees

Groundwater storage

Water stored within the ground, either in soil or rocks, beneath the water table

Channel storage

Water held within the river channel itself

Flows

Stemflow

infiltration

perlocation

surfacerunoff

throughfall

channelflow

riverurnoff

Stemflow

Water running down plant stems and branches into the soil

Infiltration

Water on the ground surface soaks into the soilP

Perlocation

Downward movement of water from the soil into the underlying rock

Surface runoff

Movement of water across the ground surface into channels

Throughfall

Water dripping off leaves during or after rainfall

Channel river

Movement of water within the channel

River runoff

Water flowing out of drainage basin

Outputs

Evaporation and transiration

Soil moisture recharge

Precipitation is higher than evapotranspiration after a dry period.Water refills the soil store that plants had previously used up

Soil moisture surplus

The soil is fully saturated and precipation continues to exceed evapration.More water than the soil can hold

Soil moisture utilisation

Stored water is used by plants when percipitatio cannot meet their  needs

Soil mositure deficit

Evapotranspiration exceeds precipitation.The soil has been used up, and there is not enough for plants

Positive water budget

When precipitation is greater than evapotranspiration. kWater is added to the soil store, leading to soil moisture recharge or surplus