Evaluating a surface energy balance model for partially wetted surfaces: Drip and micro-sprinkler systems in hazelnut orchards (Corylus avellana L.)

Authors: SOUTO, CAMILO - University Of Concepcion; LAGOS, OCTAVIO - University Of Concepcion; HOLZAPFEL, EDUARDO - University Of Concepcion; RUYBAL, CHRISTOPHER - University Of Concepcion; Bryla, David; VIDAL, GLADYS - University Of Concepcion

Submitted to: Water
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/5/2022
Publication Date: 12/8/2022
Citation: Souto, C., Lagos, O., Holzapfel, E., Ruybal, C., Bryla, D.R., Vidal, G. 2022. Evaluating a surface energy balance model for partially wetted surfaces: Drip and micro-sprinkler systems in hazelnut orchards (Corylus avellana L.). Water. 14(24). Article 4011. https://doi.org/10.3390/w14244011.
DOI: https://doi.org/10.3390/w14244011

Interpretive Summary: Knowing the exact amount of water required by a crop is essential for irrigation planning and for improving the efficiency of irrigation water use. In collaboration with faculty at the University of Concepcion in Chile, an ARS researcher in Corvallis, Oregon evaluated a new model for estimating the water requirements in hazelnut. The model was evaluated for three growing season in orchards irrigated by drip or micro-sprinklers. Results were highly correlated with measurements obtained from nearby weather stations and indicated the model accurately calculated daily and seasonal water use under a variety of growing conditions. This model will be handy for optimizing irrigation in hazelnut and other perennial cropping systems.

Technical Abstract: A multi-layer surface energy balance model, referred to as SEB-PW, was developed to estimate soil evaporation (E) and crop transpiration (T) in orchards partially wet by micro-irrigation systems. The main goal of this work was to evaluate the ability of the model to estimate actual evapotranspiration (ETa) and analyze the diurnal and seasonal dynamics of E and T in two hazelnut (Corylus avellana L.) orchards irrigated by drip or micro-sprinkler systems. The model was evaluated for three growing seasons (2017-2018, 2018-2019, and 2020-2021) in the southern Central Valley of Chile. The assessment showed that simulated hourly ETa was highly correlated with estimates from nearby weather stations and with measurements from micro-lysimeters. Within a day after irrigation, E accounted for 28-46% of ETa, depending on the year and method of irrigation. Cumulatively, E represented 15-19% of total ETa in the orchard irrigated by drip and 24-28% of total ETa in the orchard irrigated by micro-sprinklers. On average, nightly E was equal to approximately 5-10% of daily E. In accordance with the obtained results, the proposed SEB-PW model improves estimates of soil E by allowing the wetted and non-wetted areas to be estimated separately, which could be useful for optimizing irrigation methods and practices in hazelnut and other perennial cropping systems.