Effects of specific nitrogen and phosphorus addition on root and leaf functional traits of Cinnamomum camphora (L.)

This study used one-year-old Cinnamomum camphora seedlings as the research object to examine the effects of nitrogen and phosphorus ratios on the growth of C. camphora seedlings in acidic red soil. The goal of the study was to provide a scientific foundation for the high-efficiency cultivation of C. camphora plantation forests by observing the phenotypes of C. camphora seedlings and the functional indexes of roots and leaves with varying concentrations of nitrogen and phosphorus at the nitrogen-phosphorus ratio of 5:6 in the potting experiments.The results showed that: (1) in accordance with the precise ratios and concentrations, the growth indexes (ground diameter, seedling height, and chlorophyll content) in the treatments with nitrogen and phosphorus addition were significantly higher than in the other treatments; (2) compared with the control (no nitrogen and phosphorus added, CK), the nutrient additions significantly promoted the weight of the leaves and leaf phosphorus content;(3) under the first level of root sequences, there was a significant difference between the N1P1 treatment and CK in terms of average diameter, specific surface area, and tissue density, with increases of 52.05%, 57.73%, and 53.66%, respectively; (4) In the secondary root sequence, N1P1 treatment resulted in significantly greater mean diameter and tissue density compared to CK, with increases of 49.59% and 25.31%, respectively; (5) In different root sequence, N2P2 treatment resulted in significantly greater mean diameter compared to CK, with increases of 49.30% and 46.60%; and (6) fertilizer treatments, sequential levels, and their interactions had significant effects on nutrients and morpho-functional traits of the root system.in summary, The results indicated that nitrogen and phosphorus added in effective doses at specific stoichiometric ratios could significantly affect the root and leaf functional traits and promote the growth of C. camphora seedlings.