Evaluation of an empirical equation to compute the nonlinearity parameter of a root water uptake model

Abstract

AbstractThe study evaluates an empirical equation to compute the nonlinearity parameter ‘β’ of a root water uptake (RWU) model for a variety of crops. A numerical model for simulating the soil moisture dynamics incorporating the RWU model was used to evaluate the efficacy of the empirical equation. Field experiments on seven crops, namely maize, pea, wheat, sorghum, Indian mustard, guar and potato, were conducted at Hamirpur, India. The soil moisture depletion and moisture status at different depths in the crop root zone predicted by the numerical model reflected satisfactory agreement with the experimentally observed values. The qualitative and quantitative comparative analysis establishes the efficacy of the empirical nonlinearity parameter‐based RWU model in predicting moisture uptake in the root zone for different varieties of crops. The nonlinearity of moisture extraction in the root zone varies for different crops as well as during different growth stages in the same crop.