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Roots of Norway Spruce Trees Growing in CO2-Enriched Air
Pokorny, R., Tomaskova, I. and Marek, M.V. 2013. Response of Norway spruce root system to elevated atmospheric CO2 concentration. Acta Physiologiae Plantarum 35: 1807-1816.

What was done
In a study of Norway spruce (Picea abies) trees designed to evaluate much more than what meets the eye - such as what happens to their root systems when the CO2 concentration of the air about them is increased from the ambient concentration (AC = 375 ppm) to a double-ambient elevated concentration (EC = 750 ppm) - the authors grew 11-year-old saplings inside glass domes at a site in the Beskydy Mountains in the northeast part of the Czech Republic for an additional eight long years, while they measured several plant physiological properties and processes, both above- and below-ground.

What was learned
The three researchers report that the above-ground biomass of the Norway spruce saplings rose by about 12% in response to the doubling of the atmosphere's CO2 concentration, while their below-ground biomass rose by a more-than-three-times-larger 37%. Interestingly, none of this growth enhancement occurred in primary roots. Instead, it all occurred in secondary and fine roots.

What it means
As for the significance of their findings, Pokorny et al. write that "the finest roots showed the highest positive growth stimulation under elevated CO2 conditions," and they note that this phenomenon leads to a "larger root absorbing area per tree," which in turn leads to "better tree water supply under elevated CO2," with its attendant "higher chance to survive dry periods." And, of course, a larger root-absorbing area per tree also results in more nutrients being absorbed by the trees, which enables them, in the words of a famous Vulcan, to live long and prosper.

Reviewed 18 September 2013