Below-ground crop yields respond twice as strongly as above-ground crop yields to greenhouse CO2 enrichment

Key Points

• The study aims to compare the yield responses of below-ground and above-ground crops to increased CO2 levels in greenhouses.
• Global meta-analysis conducted with 466 observations from 156 greenhouse studies examining CO2 effects.
• Yield gains for below-ground and above-ground crops quantified and compared under enriched CO2 conditions.
• Trends for different crop groups analyzed based on CO2 levels.
• Below-ground crops showed a 55.0% yield increase, compared to a 29.1% increase in above-ground crops.
• Significant variation in yield response to CO2 was observed among different crop types.
• Need for further greenhouse studies on below-ground crops at CO2 levels exceeding 650 ppm.