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Abstract. Elevated surface ozone (O3) concentrations can negatively impact growth and development of crop production by reducing photosynthesis and accelerating leaf senescence. Under unabated climate change, future global O3 concentrations are expected to increase in many regions, adding additional challenges to global agricultural production. Presently, few global process-based crop models consider the effects of O3 stress on crop growth. Here, we incorporated the effects of O3 stress on photosynthesis and leaf senescence into the Decision Support System for Agrotechnology Transfer (DSSAT) crop models for maize, rice, soybean, and wheat. The advanced models reproduced the reported yield declines from observed O3-dose field experiments and O3 exposure responses reported in the literature (O3 relative yield loss RMSE <10 % across all calibrated models). Simulated crop yields decreased as daily O3 concentrations increased above 25 ppb, with average yield losses of 0.16 % to 0.82 % (maize), 0.05 % to 0.63 % (rice), 0.36 % to 0.96 % (soybean), and 0.26 % to 1.23 % (wheat) per ppb O3 increase, depending on the cultivar O3 sensitivity. Increased water deficit stress and elevated CO2 lessen the negative impact of elevated O3 on crop yield, but potential yield gains from CO2 concentration increases may be counteracted by higher O3 concentrations in the future, a potentially important constraint to global change projections for the latest process-based crop models. The improved DSSAT models with O3 representation simulate the effects of O3 stress on crop growth and yield in interaction with other growth factors and can be run in the parallel DSSAT global gridded modeling framework for future studies on O3 impacts under climate change and air pollution scenarios across agroecosystems globally.
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This content will become publicly available on January 10, 2026
Development of the DO 3 SE-Crop model to assess ozone effects on crop phenology, biomass, and yield
Abstract. A substantial body of empirical evidence exists to suggest that elevated O3 levels are causing significant impacts on wheat yields at sites representative of highly productive arable regions around the world. Here we extend the DO3SE model (designed to estimate total and stomatal O3 deposition for risk assessment) to incorporate a coupled Anet–gsto model to estimate O3 uptake; an O3 damage module (that impacts instantaneous Anet and the timing and rate of senescence); and a crop phenology, carbon allocation, and growth model based on the JULES-crop model. The model structure allows scaling from the leaf to the canopy to allow for multiple leaf populations and canopy layers. The DO3SE-Crop model is calibrated and parameterised using O3 fumigation data from Xiaoji, China, for the year 2008 and for an O3-tolerant and sensitive cultivar. The calibrated model was tested on data for different years (2007 and 2009) and for two additional cultivars and was found to simulate key physiological variables, crop development, and yield with a good level of accuracy. The DO3SE-Crop model simulated the phenological stages of crop development under ambient and elevated O3 treatments for the test datasets with an R2 of 0.95 and an RMSE of 2.5 d. The DO3SE-Crop model was also able to simulate O3-induced yield losses of ∼11 %–19 % compared to observed yield losses of 12 %–34 %, with an R2 of 0.68 (n=20) and an RMSE of 76 g m−2. Additionally, our results indicate that the variance in yield reduction is primarily attributed to the premature decrease in carbon assimilation to the grains caused by accelerated leaf senescence, which is brought forward by 3–5 d under elevated O3 treatments.
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- Award ID(s):
- 2424399
- PAR ID:
- 10638975
- Publisher / Repository:
- Copernicus
- Date Published:
- Journal Name:
- Biogeosciences
- Volume:
- 22
- Issue:
- 1
- ISSN:
- 1726-4189
- Page Range / eLocation ID:
- 181 to 212
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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