Climate-driven constraints in sustaining future wheat yield and water productivity

Abstract

Conceptualising wheat growth, yield and water productivity (WP) relationships with future climate change is necessary for sustainable agriculture and food security. This study assessed the climate change influences on wheat yield and WP with and without CO2 enrichment under semi-arid conditions. Statically bias-corrected climate change projections were coupled with AquaCrop model v5.0 to predict the wheat growth-span, yield and WP variations in Punjab, Pakistan. Acute wheat seasonal warming, characterised by sharp Tmin increase than Tmax, and substantial rainfall drops lead to short growth-spans and prompt ample yield reductions. However, CO2 enrichment promises to offset the negative wheat yield trends. Higher wheat yield vulnerability was detected for the late-season climate warming during the grain-filling stage. Wheat yield reduction and the limited influence of beneficial CO2-enrichment caused the future WP to decline consistently. CO2 enrichment featured a noteworthy mitigation role in sustaining and improving future wheat yield and WP. In conclusion, CO2 enrichment could impart some beneficial influences to wheat yield and WP, but would not fully eliminate the negative impacts of future climate warming under semi-arid conditions of Punjab, Pakistan. The reliability of such estimates demands a further in-depth examination of crop yield responses to carbon–temperature–water interactions under various field management conditions.