Calculation of available water supply in crop root zone and the water balance of crops
Determination of the water supply available in soils for crops is important for
both the calculation of water balance and the prediction of water stress. An approach
to calculations of available water content in layers of the root zone, depletion of water
during growth, and water balance, with limited access to data on farms, is presented.
Soil water retention was calculated with simple pedotransfer functions from the texture
of soil layers, root depth, and depletion function were derived from observed data; and
the potential evapotranspiration was calculated from the temperature. A comparison of
the calculated and experimental soil water contents showed a reasonable fit.