Simulating the climate change impacts and evaluating potential adaptation strategies for irrigated corn production in the Northern High Plains of Texas

Authors: KOTHARI, KRITIKA - University Of Kentucky; ALE, SRINIVASULU - Texas A&M Agrilife; Marek, Gary; MUNSTER, CLYDE - Texas A&M University; SINGH, VIJAY - Texas A&M University; CHEN, YONG - China Agricultural University; MAREK, THOMAS - Texas A&M Agrilife; XUE, QINGWU - Texas A&M Agrilife

Submitted to: Climate Risk Management
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/10/2022
Publication Date: 7/16/2022
Citation: Kothari, K., Ale, S., Marek, G.W., Munster, C.L., Singh, V.P., Chen, Y., Marek, T.H., Xue, Q. 2022. Simulating the climate change impacts and evaluating potential adaptation strategies for irrigated corn production in the Northern High Plains of Texas. Climate Risk Management. 37. Article 100446. https://doi.org/10.1016/j.crm.2022.100446.
DOI: https://doi.org/10.1016/j.crm.2022.100446

Interpretive Summary: Declining well capacities and potential climate change have led to concerns about the future of irrigated crop production in the Texas High Plains. Although the effects of climate change on agriculture are largely unknown, simulation modeling can be useful for evaluating crop adaptation strategies under future climate scenarios. An ensemble of future climate projections for precipitation, temperature, and CO2 were used to simulate irrigated corn production using a widely accepted crop growth model. Overall, grain yield was reduced in all scenarios without alteration of plant growth parameters. Lengthening of the period from silking to maturity resulted in increased yield but also increased irrigation requirements. However, adjustments of increased radiation use efficiency, delayed planting, and increased kernels per plant all resulted in increased yield with only minor effects on irrigation. These findings may aid plant breeders in developing maize hybrids that maintain yields under projected climate change conditions.

Technical Abstract: Sustaining irrigated corn (Zea mays L.) production under changing climate and reduced irrigation water availability presents a key challenge for producers in the Northern High Plains (NHP) of Texas. We assessed climate change impacts on corn production and suggested potential adaptations for weather conditions at Bushland in the NHP region using the CERES-Maize model under 36 future climate scenarios. These scenarios included nine Coupled Model Intercomparison Project Phase 5 (CMIP5) global climate models (GCMs), two representative concentration pathways (RCPs) 4.5 and 8.5, and two future time periods 2050s (2036–2065) and 2080s (2066–2095). Simulated grain corn yield decreased, under all scenarios in the future, by approximately 31% on average in the 2050s and by approximately 55% in the 2080s, under RCP 8.5, mainly due to reduced unit grain weight and biomass, and shorter crop cycle. The seasonal irrigation water requirement, on average, declined but depended on the precipitation projections. Adaptation strategies considered in this study included using ideotypes with a longer maturity, higher yield potential, and greater heat tolerance than the reference cultivar, and shifting of planting dates. By increasing the reproductive period by 13 days, grain yield could increase by 40%, but that could increase seasonal irrigation water requirement by 10%. Grain corn yield increased by 13% on average when the maximum number of kernels per plant or radiation use efficiency (RUE) were increased by 15%, with minor changes in seasonal irrigation water requirement. Heat tolerant ideotypes showed yield advantage over the reference cultivar without much change in irrigation. Delayed planting increased grain yield in the future. Overall, our results indicated that the producers could see grain yield declines under climate change without adaptation. Ideotypes with greater silking to maturity period, potential number of kernels per plant, RUE, and heat tolerance during grain filling, showed yield benefits in the future. Delaying planting was effective in reducing seasonal irrigation water requirement and increasing grain yield.