Impacts of meteorological factors and ozone variation on crop yields in China concerning carbon neutrality objectives in 2060.

Carbon neutrality objectives affect meteorology and ozone (O 3) concentration in China, both of which would influence crop yields, thus food security. However, the joint impact of these two factors on crop yields in China is not clear. In this study, we investigated future trends in China's maize, rice, soybean, and wheat yields under a carbon-neutral scenario considering both regional emission reduction and global climate change in 2060. By combining a process-based crop model (Agricultural Production Systems sIMulator, APSIM) with O 3 exposure equations, the impacts of regional emission reduction and global climate change were studied. The results suggest that regional emission reduction dominated the increase in yield by reducing the O 3 concentration, whereas global climate change led to yield loss mainly through meteorological factors. The national yield decreases for the four crops ranged from 1.0% to 38.0% owing to meteorological factors, while O 3 reduction resulted in additional yield increases ranging from 2.8% to 7.0%. The combined effect of carbon neutrality, which included both meteorological factors and O 3 concentration, resulted in changes to the yields of maize, rice, soybean, and wheat of +4.3%, -7.3%, -24.0%, and -31.7%, respectively. It seems that crop production loss caused by meteorological factors in 2060 would be mitigated by the O 3 reduction. Given the advantages of declining O 3 concentration, regional emission reduction would likely benefit crop growth. However, global climate change may offset the benefits and threaten food production in China. Therefore, more strict emission reduction policies and global climate change mitigation actions are necessary to ensure food security in China. [Display omitted] • Low carbon emissions would lead to increased crop yields in China. • Crop yield loss is mitigated owing to ozone decreases induced by emission reduction. • Global climate change would cause yield loss mainly through meteorological factors. [ABSTRACT FROM AUTHOR]