Nitrogen and Carbon Cycling in a Grassland Community Ecosystem as Affected by Elevated Atmospheric CO₂

Table 1

Effect of atmospheric CO₂ concentration on soil N mineralization during a 60-day soil incubation at three soil depth increments^†.

CO2 level	0–20 days			0–60 days
	Depth
	0–20 cm	20–50 cm	50–80 cm	0–20 cm	20–50 cm	50–80 cm
(μmol mol^−1)	(mg kg^−1)
385	6.86 a	1.91 a	1.37 a	7.51 a	4.01 a	4.54 a
690	2.91 b	0.59 a	0.69 a	7.85 b	3.86 a	4.89 a
980	3.52 c	2.91 a	0.46 a	10.04 c	3.30 a	3.89 a

^†Values represent means of three replications. Means within a column for each sampling date followed by the same letter do not differ significantly (𝛼=0.1).