Utilizing digital image processing and two-source energy balance model for the estimation of evapotranspiration of dry edible beans in western Nebraska

Having an accurate yet simple method to estimate crop evapotranspiration (ETC) is a vital component of reliable irrigation scheduling. In this study, two versions the two-source energy balance (TSEB) model: TSEB model with Priestley–Taylor equation (TSEB-PT) and Penman–Monteith (TSEB-PM), were used ETC dry edible beans in western Nebraska. Compared previous studies, study unique that Visual Basic software—Crop Canopy Image Analyzer (CCIA) was developed process digitally captured RGB canopy images obtain necessary cover (CC) parameters for models such as CC percentage leaf shape factor (leaf area divided by its perimeter). Software-estimated closely correlated commercial sensor-derived R2 0.96. Additionally, estimated measured 0.99. Both TSEB-PT TSEB-PM well fully irrigated root-mean-square error (RMSE) ranged from 0.95 1.63 mm day−1 2018, 0.75 1.35 2019, compared FAO56. Furthermore, soil water balance-derived RMSE 2.03 9.65 approximate 1-week period under four treatments ranging land irrigated. The proposed methods integrating digital image processing models, have great potential be automated field-scale operations various management scenarios many crops.