Food for Thought: Lower-Than-Expected Crop Yield Stimulation with Rising CO 2 Concentrations
- Resource Type
- Authors
- Donald R. Ort; Elizabeth A. Ainsworth; Stephen P. Long; Andrew D. B. Leakey; Josef Nösberger
- Source
- Science. 312:1918-1921
- Subject
- Crops, Agricultural
Nitrogen
Enclosure
Climate change
Poaceae
Zea mays
chemistry.chemical_compound
Ozone
Human fertilization
Meta-Analysis as Topic
Biomass
Photosynthesis
Fertilizers
Water content
Sorghum
Triticum
Multidisciplinary
Atmosphere
Crop yield
Temperature
Water
Stimulating environment
Carbon Dioxide
chemistry
Agronomy
Carbon dioxide
Environmental science
Soybeans
Forecasting
Field conditions
- Language
- ISSN
- 1095-9203
0036-8075
Model projections suggest that although increased temperature and decreased soil moisture will act to reduce global crop yields by 2050, the direct fertilization effect of rising carbon dioxide concentration ([CO 2 ]) will offset these losses. The CO 2 fertilization factors used in models to project future yields were derived from enclosure studies conducted approximately 20 years ago. Free-air concentration enrichment (FACE) technology has now facilitated large-scale trials of the major grain crops at elevated [CO 2 ] under fully open-air field conditions. In those trials, elevated [CO 2 ] enhanced yield by ∼50% less than in enclosure studies. This casts serious doubt on projections that rising [CO 2 ] will fully offset losses due to climate change.