Assessing Sustainable Adaptation Strategies for Water Productivity and Crop Yields Under Future Climate Scenarios in a Water-Stressed Watershed

Sustainable agriculture in water-limited regions requires understanding how future climate change may affect crop water use and productivity and whether locally feasible adaptations can offset adverse impacts. This study used an improved SWAT (Soil and Water Assessment Tool) model to simulate multiple future climate scenarios—five single-factor adaptation scenarios, including early or late sowing, long- or short-season cultivars, and crop substitution, and one integrated scenario—in the Palo Duro Watershed of the Texas High Plains. Under future climate, yields declined by 6.7–13.1% for irrigated corn (Zea mays L.) and 11.6–34.1% for irrigated sorghum (Sorghum bicolor L.), but increased by 8.0–32.8% and 8.4–33.7% for dryland and irrigated winter wheat (Triticum aestivum L.), respectively. Early sowing improved yields and water productivity (WP) for irrigated corn, irrigated sorghum, and dryland winter wheat. However, long-season cultivars increased corn and sorghum yields and WP with greater irrigation water use. Crop substitution was generally unfavorable under local conditions. A combined strategy of early sowing and long-season cultivars would increase yields and WP for irrigated corn, irrigated sorghum, and dryland winter wheat, whereas business-as-usual management remained appropriate for irrigated winter wheat. These findings support crop-specific adaptation planning for climate-resilient agriculture and water-resource management in semi-arid systems.