The water balance Flashcards
What is the formula for precipitation?
P = Q + E +/- S
- P = precipitation
- Q = river run off
- E = evapotranspiration
- S = storage in soil and rocks
What is soil moisture recharge?
The previously depleted soil store begins to refill, as precipitation exceeds evapotranspiration and plant use.
What is soil moisture utilisation?
When saturated soil water stores are being used by growing plants during the growing season.
What is soil moisture deficit?
Is when all moisture has been absorbed by plants and removed by evapotranspiration, there is also little precipitation to recharge.
What is soil moisture surplus?
Occurs when the soil water store is completely saturated due to high rainfall and low evapotranspiration as well as low usage.
What is field capacity?
When the soil store is unable to absorb anymore water and every gap/ pore is filled.
What is run off?
The proportion of total precipitation that makes its way into streams and rivers.
What is the water balance?
This is the balance between inputs (precipitation) and outputs (run-off, evapotranspiration, soil and ground water storage).
- The character of the drainage basin will affect this.
What is the soil water/ moisture budget?
This is how the store of water in the soil is affected by processes of precipitation and evapotranspiration.
