Toward Nutrient Solution Composition Control in Hydroponic System

Abstract

The concept and method for estimating the uptake rate of water and ions by hydroponically grown plants based on the water and ion balance in the culture beds are proposed. The method is also used to estimate the transpiration rate and the increase in fresh weight of plants. The concept of estimating the ion concentration of NH4+, Mg2+, Cl-, PO43- (H2PO4-), and SO42-using the measured data on NO3, K+, Ca2+, Na+, EC(electric conductivity), and pH is described. EC of the nutrient solution is related to the total sum of the Eq (equivalent) concentration of all types of ions.