Increased Carbon Dioxide Levels in Air Restrict Plants' Ability to Absorb Nutrients

The rapidly rising levels of carbon dioxide in the atmosphere affect plants' absorption of nitrogen, which is the nutrient that restricts crop growth in most terrestrial ecosystems.  Researchers at the University of Gothenburg have now revealed that the concentration of nitrogen in plants' tissue is lower in air with high levels of carbon dioxide, regardless of whether or not the plants' growth is stimulated.  The study has been published in the journal Global Change Biology.
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Significance of food quality, biodiversity and productivity
When carbon dioxide levels in the air increase, crops in future will have a reduced nitrogen content, and therefore reduced protein levels.  The study found this for both wheat and rice, the two most important crops globally.  The study also reveals that the strength of the effect varies in different species of grassland, which may impact on the species composition of these ecosystems.

"For all types of ecosystem the results show that high carbon dioxide levels can impede plants' ability to absorb nitrogen, and that this negative effect is partly why raised carbon dioxide has a marginal or non-existent effect on growth in many ecosystems," says Johan Uddling.

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