Hidden shift of the ionome of plants exposed to elevated CO2 depletes minerals at the base of human nutrition
Abstract
Mineral malnutrition stemming from undiversified plant-based diets is a top global challenge. In C3 plants (e.g., rice, wheat), elevated concentrations of atmospheric carbon dioxide (eCO2) reduce protein and nitrogen concentrations, and can increase the total nonstructural carbohydrates (TNC; mainly starch, sugars). However, contradictory findings have obscured the effect of eCO2 on the ionome - the mineral and trace-element composition - of plants. Consequently, CO2-induced shifts in plant quality have been ignored in the estimation of the impact of global change on humans. This study shows that eCO2 reduces the overall mineral concentrations (-8%, 95% confidence interval: -9.1 to -6.9, p<0.00001) and increases TNC:minerals > carbon:minerals in C3 plants. The meta-analysis of 7,761 observations, including 2,264 observations at state of the art FACE centers, covers 130 species/cultivars. The attained statistical power reveals that the shift is systemic and global. Its potential to exacerbate the prevalence of 'hidden hunger' and obesity is discussed.
Article and author information
Author details
Reviewing Editor
- Ian T Baldwin, Max Planck Institute for Chemical Ecology, Germany
Publication history
- Received: January 8, 2014
- Accepted: April 25, 2014
- Accepted Manuscript published: May 7, 2014 (version 1)
- Accepted Manuscript updated: May 13, 2014 (version 2)
- Version of Record published: May 27, 2014 (version 3)
Copyright
© 2014, Loladze & Baldwin
This article is distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use and redistribution provided that the original author and source are credited.
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