High nutrient supply and interspecific belowground competition enhance the relative performance of Picea mariana (Mill). B.S.P seedlings over Picea glauca [Moench] Voss. under elevated CO2

Table 4 P values from ANOVA on the effects of CO₂, belowground competition (BGC), nutrient supply (N), and species (S) on foliar nutrient concentration, nutrient (N, P, and K) use efficiency, total root length (TRL), mean root diameter (MRD), and root length density (RLD) and of black spruce and white spruce seedlings. The seedlings were exposed to two CO₂ concentrations (380 and 720 µmol mol⁻¹) with and belowground competition at two nutrient levels. Probabilities ≤ 0.05 were underlined and bold-faced

Factor	N	P	K	NUE	PUE	TRL	MRD	RLD
CO₂	0.96	0.36	0.29	0.01	0.00	0.105	0.956	0.105
BGC	0.23	0.14	0.21	0.06	0.01	0.164	0.014	0.164
CO₂*BGC	0.57	0.54	0.74	0.05	0.01	0.385	0.029	0.385
N	0.00	0.02	0.01	0.09	0.99	0.568	0.811	0.568
CO₂*N	0.27	0.89	0.36	0.08	0.40	0.549	0.083	0.549
BGC*N	0.13	0.87	0.04	0.04	0.37	0.249	0.217	0.249
CO₂BGCN	0.34	0.95	0.20	0.21	0.89	0.341	0.885	0.341
S	0.01	0.00	0.00	0.00	0.00	< .001	0.612	< .001
CO₂*S	0.59	0.84	0.15	0.11	0.00	0.035	0.983	0.035
BGC*S	0.16	0.04	0.58	0.72	0.20	0.294	0.236	0.294
N*S	0.14	0.24	0.52	0.16	0.00	0.005	0.410	0.005
CO₂BGCS	0.01	0.01	0.77	0.05	0.04	0.040	< .001	0.040
CO₂NS	0.18	0.11	0.81	0.17	0.01	0.001	0.016	0.001
BGCNS	0.94	0.08	0.25	0.43	0.04	0.631	0.220	0.631
CO₂BGCN*S	0.07	0.63	0.07	0.21	0.01	0.627	0.916	0.627

ISSN: 1297-966X