Comparison of surface resistance‐based models for estimating maize evapotranspiration in a humid region of China

Abstract Accurate simulation of evapotranspiration (ET) is essential to enhance efficient irrigation management in the maize field. Here, we evaluated performance four mathematical models for estimating ET maize. The based on surface resistance calculate from different vapor sources, which are Penman‐Monteith (PM) through “big leaf” model, Shuttleworth‐Wallace (SW) model distinguishing between soil and canopy, clumping (C) soils under canopy bare soil, seasonal (Cj) dividing into transpiration sunlit leaves shaded leaves, evaporation surface, gap fraction, surfaces. were calibrated by measured a weighing lysimeter, sap flux method, micro‐lysimeters 2014, 2015, 2017. Results showed that daily was 3.32 mm/day during full‐grown stage maize, mean 1.46 mm/day. flow plus micro‐lysimeter method consistent with large‐weighted lysimeter measuring ET. For simulating versus hourly transpiration, Cj performed better than C slope 0.94, determination coefficient ( R 2 ) 0.85, absolute error (MAE) 0.08 mm/h, modified agreement index d 0.81. In evaporation, also had higher less MAE SW models. Nevertheless, yielded increased decreased simulated most sensitive environmental factor temperature. With 50% increase temperature, ET, 45%, 36%, 69%, respectively. summary, improved accuracy helped separate plant thus giving an available approach precision water planting systems.