Abstract:
Objective To examines the effects of cultivar and dioecy on stoichiometry of Torreya grandis, and provide references for the management of T. grandis stands.
Method 300-years-old female (T. grandis cv. 'Dielsii' and T. grandis cv. 'Merrilli') and male T. grandis in T. grandis National Forest Park located in Zhuji of Zhejiang Province were used as test materials. The plant and soil samples were collected from the field to analyze the C, N, P contents and their stoichiometric characteristics.
Result (1) There was no significant difference in C, N, P contents and stoichiometric characteristics between T. grandis cv. 'Dielsii' and male T. grandis. Dioecy had no significant effects on the stoichiometry of T. grandis. (2) The contents of C, N, P and their stoichiometric characteristics of T. grandis cv. 'Merrilli' were significantly different from T. grandis cv. 'Dielsii' and male T. grandis. Among them, the C content in T. grandis cv. 'Merrilli' leaves (533.0 g·kg-1) was significantly higher than that in T. grandis cv. 'Dielsii' (502.8 g·kg-1) and male T. grandis (502.7 g·kg-1), and the P content in T. grandis cv. 'Dielsii' roots (1.5 g·kg-1) was significantly higher than that in T. grandis cv. 'Dielsii' (0.9 g·kg-1) and male T. grandis (0.9 g·kg-1). Generally, the C:N ratio of T. grandis cv. 'Merrilli' was higher than that of T. grandis cv. 'Dielsii' and male T. grandis, while the C:P and N:P ratios were lower. (3) The contents of C, N and P in different organs of T. grandis exhibited the same trend. The content of C and P displayed in the order of leaves > branches > roots, leaves were the highest, and the content of C in root and the content of P in branch were the lowest. And N content of leaves were significantly higher than of roots and branches. The C:N and C:P ratios of different organs of T. grandis cv. 'Dielsii' and male T. grandis were roots > branches > leaves, and the N:P ratio was roots > leaves > branches. The C:N ratio of T. grandis cv. 'Merrilli' was branches > roots > leaves, the C:P ratio was roots > branches > leaves, and the N:P was leaves> roots > branches.
Conclusion Dioecy of T. grandis shows no significant effect on the stoichiometric characteristics of tree, so it can be ignored during the management. The stoichiometric characteristics of T. grandis is significantly affected by management measures.
下载: