My name is Galina Stulina. I have been calculate  in water consumption, requirement  of crops in Uzbekistan for many years. I advise you to read FAO issues 24 and 56. Estimated evapotranspiration of crops with CROPWAT program ( FAO) _ is the most common method that is used is determined by the potential evapotranspiration ETo depending on climate and estimated ETc based crop coefficients determining the evapotranspiration for each crop. The disadvantage of this program is that it does not take into account recharge from groundwater in the balance. This way you will get the amount of water consumption required for each plant and will be able to calculate the irrigation efficiency knowing the actual water supply. That is, you can say that the plant needed so much water , but was served on the field of water more or less. This will be the efficiency of irrigation management. Another question is to evaluate the actual evapotranspiration of the ETa . This can be done in two ways - by installing lysimeters with plants on the field and periodically weighing them to find out the actual evapotranspiration The second method is to determine the ETa from satellite images using the leaf surface index NDVI.

Published February 21, 2020 08:01 by Galina Stulina, SIC ICWC - Researher