Dry-heat climate impacts on greenhouse gas emission intensity in wheat production: insights and mitigation strategies

Authors: SHI, YU - Northwest A&f University; PAN, SHUFEN - Boston College; YOU, YONGFA - Boston College; Prior, Stephen; TIAN, DI - Auburn University; YU, HUIQIAN - Auburn University; YU, QIANG - Northwest A&f University; TIAN, HANQIN - Boston College

Submitted to: Global Change Biology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/28/2025
Publication Date: N/A
Citation: N/A

Interpretive Summary: Our study indicated that the effects (positive or negative) of tillage practices (CT and NT) on the sensitivity of yield and GHGs vary across the US wheat region. Appropriate tillage strategies are required to partially offset climate shock from dry-heat extremes since strong spatial heterogeneity of tillage effects is closely associated with local environments. Under unfavorable tillage management, soil C will generally decrease over time, leading to increased C sensitivity to EDHs. Efforts to implement smart agricultural practices (genetic improvement, automation and robotic farming, and ecological agriculture) will be needed to minimize extreme weather impacts. Uncertainty in yield and GHGs prediction will be amplified under future warming due to rapidly increasing sensitivity of crop GHGI to EDHs. Findings highlighted the urgent need to consider differences in GHGI sensitivity to dry-heat stress among crop types and its long-term dynamics in climate-smart agriculture practices.

Technical Abstract: Extreme dry-heat conditions (EDHs) threaten agricultural production and stimulate greenhouse gas (GHG) emissions, increasing the climate cost of food production. However, the long-term sensitivity and its dynamics of cropland GHG emissions intensity (GHGI, emissions per unit food production) to EDHs, as well as the mitigation potential of climate-smart practices, remain uncertain. Using a model-data integration framework that couples an advanced agricultural ecosystem model with multiple in situ observations revealed that EDHs increased GHGI in over 80% of U.S. wheat-growing regions over six decades. The sensitivity of GHGI to EDHs in spring wheat increased by 130% (80.3–241.3%) from the 1979s to 2018s, while the sensitivity of GHGI in winter wheat spiked sharply after the 2008s, reaching a 607% increase (191.8–1325.2%). The sensitivity hotspots are widely distributed in the US Northern and Central Plains. Implementation of climate-smart tillage schemes effectively decreased dry-heat sensitivity in about one-third of wheat regions, leading to a notable 9.8% reduction (5.8–17.7%) in GHGI sensitivity for spring wheat and a 13.3% reduction (8.0–20.9%) for winter wheat across the U.S. Our findings emphasize the urgent focus on increased climate cost during food production and mitigation potential of climate-smart management in a warming climate.