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The effect of elevated carbon dioxide concentration ((CO2]) on fertilizer nitrogen (N) recovery in wheat grown under open-air conditions in the North China Plain has not been reported. Winter wheat (Triticum aestivum L cv. Zhongmai 175) was grown to maturity under ambient (415 +/- 16 mu mol mol(-1)) and elevated (550 +/- 17 mu mol mol(-1)) [CO2] at the free-air carbon dioxide enrichment (FACE) facility in a semi-arid region in northern China. We applied N-15-enriched (10.22 at.%) granular urea to microplots at either 25 or 95 kg N ha(-1) at the stem elongation stage of wheat. Elevated [CO2] increased wheat biomass (29%) and grain yield (23%), but had no significant effect on grain protein concentration. The [CO2]-induced N demand (19%) was satisfied mostly by increased uptake of indigenous N (19%). Elevated [CO2] had no significant effect on the recovery of fertilizer N-15 (applied at stem elongation) by the plant or on the amount that remained in the soil. Of the fertilizer N-15 assimilated by the whole plant, the allocation to grain increased from 62% under ambient [CO2] to 72% under elevated [CO2]. High N application did not increase wheat biomass, grain protein concentration, or fertilizer N recovery in the plant, irrespective of [CO2]. The results suggest that current fertilizer practice in a wheat cropping system such as in the North China Plain will have to be adjusted in a CO2-rich world. (C) 2012 Published by Elsevier B.V.