Linear background temperature dependency of winter wheat yield across the China’s main producing areas under climate warming

Abstract

Context

Climate warming is widely anticipated to impact winter wheat yields, yet the regional disparities and uncertainties associated with its effects on these yields complicate the extrapolation of experimental findings to broader geographical areas and larger scales.

Objective

Our research aims to clarify the regional response characteristics of winter wheat yields to climate warming in China.

Methods

Our research compiled data from the literature published in recent years on warming experiments in main winter wheat-producing areas of China, as well as from our multi-year warming experiments. Our study developed a spatial projection model to forecast alterations in winter wheat yields under prospective climate scenarios. This model integrated meta-analytic approaches, advanced mathematical statistical methods, and sophisticated spatial analysis techniques.

Results

This study demonstrated that the impact of global warming on winter wheat yields exhibited significant regional heterogeneity, with effects strongly related to the initial background air temperature of the region. A diurnal continuous warming response model constructed based on meta-analysis reveals a distinct threshold characteristic in winter wheat's response to climate warming. When the background air temperature is below 10.7°C, warming can increase winter wheat yields, whereas above this threshold, it may lead to a reduction in yields. For China's main winter wheat production areas, a 1°C increase in temperature can lead to a 5.12 % increase in yield. And according to current climate scenario predictions, by 2050, climate warming is projected to result in a net increase of 6.02 % in winter wheat production.

Conclusion

The impact of climate warming on winter wheat yields exhibits a linear response relationship with the regional background temperature. A critical temperature threshold of 10.7°C divides winter wheat production areas into warming-benefit zones and warming-stress zones. This finding suggests that the simplistic assumption of "warming leads to yield reduction" may introduce systematic bias in assessing the effects of climate change. It highlights the necessity of incorporating regional temperature baselines for differentiated predictions.

Implications

This study provides decision-making support for regional winter wheat production. By identifying suitable planting areas for winter wheat based on temperature response thresholds, it guides the moderate expansion of cultivation in low-temperature potential zones and the adjustment of variety distribution in high-temperature risk zones. It offers a quantitative basis for developing differentiated adaptation strategies for winter wheat production, such as variety breeding and sowing date adjustments. Additionally, embedding temperature threshold parameters into crop models enhances the spatiotemporal precision of climate change impact assessments.