摘 要 ：生物量分配是植物净碳获取的重要驱动因素，当年生小枝内部的生物量分配是植物生活史对策研究的一个重要内容。本文采用标准化主轴估计(Standardized major axis estimation，SMA)和系统独立比较分析(Phy1ogenetica11y independent contrast analysis,PIC)的方法，研究了贡嘎山常绿和落叶阔叶木本植物当年生小枝内各组分生物量分配之间的关系。结果显示：小枝干重与茎干重、叶(含叶柄)干重和叶片(不含叶柄)干重，以及茎干重与叶(含叶柄)干重之间均呈极显著的等速生长关系，表明分配到叶或者叶片中的生物量独立于小枝生物量；叶柄干重与叶片(不含叶柄)干重和小枝干重呈极显著的异速生长关系，显示叶柄对小枝内的生物量分配具有重要的影响；在某一给定的小枝干重或叶片干重时，常绿物种比落叶物种具有更大的叶柄干重，即更大的支撑投资。这些结果表明叶柄作为叶片生物量最大化的一个不利因素，影响了小枝内的生物量分配，并且叶片与其支撑结构之间的异速生长关系随叶片生活型的变化而变化。
Abstract:Biomass allocation in current-year shoots (twigs) is an important parameter categorizing plant life history strategies, and it is an important driving factor for plant net carbon obtaining. In this study, the scaling relationships of biomass allocation within twigs of evergreen and deciduous species at Gongga mountain were estimated using standardized major axis estimation(SMA) and the phylogenetically independent contrast analysis(PIC) methods. The results indicated: Isometric relationships were found between twig mass and stem mass, leaf mass and lamina mass, as well as between stem mass and leaf mass, suggesting that the biomass allocation to either leaves or laminas were independent of twig mass; allometric relationships were found between petiole mass and leaf mass, as well as between petiole mass and twig mass, indicating the importance of leaf petioles to the within-twig biomass allocation; evergreen species tended to have a greater petiole mass at a given twig or lamina mass than deciduous species. Our results indicate that petioles serve as an adverse forcing on the maximization of lamina biomass and the allometric relationship between lamina and lamina support varies with species type.