关键词: 珙桐, 植物功能性状, 生活史, 权衡关系, 经济谱策略, 养分利用策略

Abstract: Aims Davidia involucrata Baill. is a nationally protected plant. This study investigates the functional trait differences and growth strategies of the leaves, stems, and roots at different life history stages of D. involucrata, providing scientific basis for the conservation and restoration of rare and endangered plants. Methods This study focuses on seedlings, saplings, and adult trees of D. involucrata cultivated in Yantai. Functional traits of leaves, stems, and roots were analyzed to explore the differences in these traits across different life stages, as well as the key growth strategies of each organ and their impact on overall growth. Important findings (1) Leaves, stems, and roots exhibited an "acquisitive strategy" at the seedling and sapling stages but shifted to a "conservative strategy" at the adult stage. From the seedling to adult stage, leaf chemical element concentrations decreased and leaf morphology became thicker and denser, indicating a transition from rapid growth to a stable strategy emphasizing structural reinforcement and defense. Stem dry matter content and wood density increased while chemical element concentrations declined, indicating a shift from rapid growth to enhanced structural strength and mechanical support. Specific root length, root dry matter content, and vessel density increased, with roots transitioning from rapid proliferation to a strategy characterized by structural stability and strengthened defense. (2) At the seedling stage, leaves, stems, roots, and the whole plant displayed a "P-use strategy", characterized by relatively high P concentration, C:N ratio, and specific root length, with resources preferentially allocated to the construction of fundamental biological structures and rapid expansion of organs to facilitate efficient resource acquisition. At the sapling stage, an "N-use strategy" predominated, with higher N concentration and N:P ratio, indicating increased investment in nitrogen for the synthesis of proteins, nucleic acids, and chlorophyll to enhance photosynthetic capacity and support rapid growth. At the adult stage, roots exhibited a "P-use strategy", whereas leaves, stems, and the whole plant reached a relative balance in N-P nutrient utilization. (3) The resource investment and structural construction strategies of the stem, root, and whole plant exhibit significant synergy during the seedling stage. The resource investment and structural construction strategies of the root and whole plant exhibit significant synergy during the sapling stage. The nutrient-use strategies of the stem and whole plant exhibit significant synergy during the adult stage. The results provided a scientific basis for the conservation practices of translocated D. involucrata.

Key words: Davidia involucrata Baill., plant functional trait,life history, trade-offs, plant economic spectrum, nutrient use strategy