What was done
The authors utilized 32 open-top chambers to investigate the effects of atmospheric CO2 enrichment (from 355 to 680 ppm) on leaf carbohydrate and nitrogen status in four different species of an alpine ecosystem in the Swiss Central Alps over a period of three years.

What was learned
Two of the four species registered increases in green-leaf total non-structural carbohydrates and decreases in green-leaf nitrogen concentration.  However, none of these changes in active plant tissue translated into compositional changes in naturally-senesced litter.

What it means
With no CO2-induced changes in the chemical composition of the total mix of alpine ecosystem leaf litter, ecosystem decomposition rates would be expected to be unaffected by the ongoing rise in the air's CO2 content, resulting in a likely increase in soil carbon storage, which should act to moderate the rate of rise of the atmosphere's CO2 concentration.