Article,
Response of rice production to elevated CO2 and its interaction with rising temperature or nitrogen supply: a meta-analysis
CLIMATIC CHANGE, (June 2015)
DOI: \%7B10.1007/s10584-015-1374-6\%7D
Abstract
We used meta-analysis to synthesize 125 studies assessing the responses of rice production to elevated atmospheric carbon dioxide concentration (CO2), and the interaction of elevated CO2 with rising temperature or N supply. Elevated CO2 significantly enhanced rice yield by 20 \%, despite no significant increase in grain size and harvest index at elevated CO2. Belowground biomass increased at elevated CO2 to a larger extent than aboveground biomass. Among the Japonica, Indica and Hybrid rice cultivars, Hybrid cultivars generally showed the greatest growth response to elevated CO2. The maximum enhancement of rice yield was observed at 600-699 ppm CO2 with less benefit in studies with lower or higher elevated CO2 levels. Rice yield responses to elevated CO2 were smaller in FACE compared with the other fumigation methods, largely associated with lower photosynthesis. Increases in rice yield at elevated CO2 were constrained by limited N supply. The detrimental effect of rising temperature on spikelet fertility and harvest index were not be fully counteracted by elevated CO2 effects. Together, the results of this meta-analysis suggest that rising CO2 and warming accompanied by low N supply are unlikely to stimulate rice production, especially with the current trajectory of emissions scenarios.
