Adaptation of MOPECO for water management decisions in the Texas High Plains

Authors: Schwartz, Robert; DOMINGUEZ, ALFONSO - University Of Castilla-La Mancha(UCLM); PARDO, JOSE JESUS - University Of Castilla-La Mancha(UCLM); Baker, Trinity; Klopp, Hans; PARKER, DAVID - West Texas A & M University; BELL, JOURDAN - Texas A&M Agrilife; GUERRERO, BRIDGET - West Texas A & M University; Baumhardt, Roland - Louis; Colaizzi, Paul

Submitted to: Meeting Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 9/5/2022
Publication Date: 9/5/2022
Citation: Schwartz, R.C., Dominguez, A., Pardo, J., Baker, T.J., Klopp, H.W., Parker, D., Bell, J.M., Guerrero, B., Baumhardt, R.L., Colaizzi, P.D. 2022. Adaptation of MOPECO for water management decisions in the Texas High Plains. In: Proceedings for the International Conference for Dessemination of PRIMA Project Results and Interregional Conference of CIGR Section 1, September 5, 2022, in Albacete, Spain. Virtual.

Interpretive Summary: The High Plains aquifer is an important source of water for irrigation throughout the U.S. Great Plains. Approximately 32% of groundwater used for irrigation in the U.S. is pumped from the High Plains Aquifer. This irrigation water generates 10% of the crop sales in the United States. In the Texas High Plains and western Kansas, the aquifer is slowly being depleted resulting in reduced well yields. Inability to meet peak water demands of corn and other crops under limited irrigation reduces yield and profitability, especially in years with below normal precipitation. Crop models can provide guidance to growers in selecting appropriate management interventions required to maximize profitability when irrigation water is limited. For example, reducing the area irrigated may increase or decrease net returns, depending on crop yields in the irrigated area and costs of production. Crop models can generate how profitability changes with irrigated area so that growers can make informed decisions. This paper summarizes the necessary model adaptations required to simulate center pivot irrigation of corn and provide realistic results under the climate and constraints typical of the Texas High Plains.

Technical Abstract: The High Plains aquifer is an important source of water for irrigation throughout the U.S. Great Plains. Approximately 32% of groundwater used for irrigation in the U.S. is pumped from the High Plains Aquifer which generates 10% of the crop sales in the United States. In the Texas High Plains and western Kansas, the aquifer is slowly being depleted resulting in reduced well yields. Inability to meet peak water demands of maize and other crops under constrained irrigation capacities (flow rate per unit land area) decreases yield and profitability, especially in years with below normal growing season precipitation. The MOPECO crop model was adapted to simulate maize water use and yield under center pivot irrigation and evaluate water allocation strategies under limited irrigation capacities. This paper summarizes some of the modifications and adaptations of the MOPECO model that were necessary to provide realistic results under the climate and constraints typical of the Texas High Plains. It is hoped that the model adaptations of MOPECO implemented to address the climate and irrigation constraints in this region can provide helpful insight and guidance for model adaptation in other zones.