CO₂ fertilization of crops offsets yield losses due to future surface ozone damage and climate change

Abstract

Tropospheric ozone (O3) is harmful to plant productivity and negatively impacts crop yields. O3 concentrations are projected to decrease globally in the optimistic Representative Concentration Pathway of 2.6 W m–2 (RCP2.6) but increase globally following the high-emission scenario under the RCP8.5, with substantial implications for global food security. The damaging effect of O3 on future crop yield is affected by CO2 fertilization and climate change, and their interactions for RCP scenarios have yet to be quantified. In this study, we used the Joint UK Land Environment Simulator modified to include crops (JULES-crop) to quantify the impacts, and relative importance of present-day and future O3, CO2 concentration and meteorology on crop production at the regional scale until 2100 following RCP2.6 and RCP8.5 scenarios. We focus on eight major crop-producing regions that cover the production of wheat, soybean, maize, and rice. Our results show that CO2 alone has the largest effect on regional yields, followed by climate and O3. However, the CO2 fertilization effect is offset by the negative impact of tropospheric O3 in regions with high O3 concentrations, such as South Asia and China. Simulated crop yields in 2050 were compared with Food and Agriculture Organisation (FAO) statistics to investigate the differences between a socioeconomic and a biophysical process-based approach. Results showed that FAO estimates are closer to our JULES-crop RCP8.5 scenario. This study demonstrates that air pollution could be the biggest threat to future food production and highlights an urgent policy need to mitigate the threat of climate change and O3 pollution on food security.

Towards diverse agricultural land uses: socio-ecological implications of European agricultural pathways for a Swiss orchard region

“…Eventually, other climate change effects could have a considerable influence on yield patterns. For example, CO 2 fertilisation effects might at least partially compensate for potential reductions in plant growth and net primary production (Leung et al 2022 ). Nonetheless, it seems exceedingly optimistic to posit that the effects of increased ambient CO 2 may completely manifest as yield improvements (Long et al 2004 , 2006 ; Wang et al 2020 ).…”

Crop models and their use in assessing crop production and food security: A review

“…As such, it helps identify and quantify detrimental events to the environment. When coupled with atmospheric models, it is also a good method to predict how land use and climate change influence carbon and hydrological cycles (Buechel, 2021), determine climate change effects on ecosystems, allowing mitigation and restoration (Littleton et al, 2021), identify drought occurrence and its impact on soil moisture (Zeri et al, 2022) find the effects from climate and greenhouse gases on crop production (Leung et al, 2022) compare the evaluation of anthropogenic and climatic impacts on crop production (Leung et al, 2022) and create an index to food security stability from JULES outputs of productivity (Singh et al, 2022).…”