[Variations in leaf C, N, P stoichiometry of Quercus acutissima provenance forests.]

In order to explore the variations in leaf stoichiometry based on the method of forest tree breeding, we determined the leaf carbon (C), nitrogen (N), phosphorus (P) stoichiometry among 29 Quercus acutissima provenances grown at 3 sites. The results indicated that the site (environment) effect was statistically significant on leaf stoichiometry, with 13.2%-66.7% of the total variations accounted for leaf C, N, P, C/N, C/P and N/P, while the provenance effect was insignificant and only accounted for 2.9%-11.0% of total variations for leaf stoichiometry. The leaf N and C/N, N and N/P, P and C/P, P and N/P were significantly correlated, and the common standardized major axis slope was also observed among three sites and two provenance groups. It could be concluded that the leaf stoichiometry of Q. acutissima, was mainly determined by its growing environment, due to the similar C, N and P biochemical pathways at species level. The stable correlation coefficients among sites and provenances implied the coupling ratios of leaf stoichiometry were independent of environment and provenance, which supported the leaf stoichiometric homeostasis.