垫状点地梅是青藏高原最具代表性的垫状植物之一，其个体年龄的判定，对于揭示高寒生境下垫状植物的生长特征和规律具有重要意义，同时也是研究青藏高原植物种群结构及动态的基础和关键。在研究和分析垫状点地梅植株构型特征的基础上，结合其物候特性和采样时间，探索性地找到了一种判定该物种个体实际年龄的方法，并基于垫状点地梅植株的年龄研究了其生长规律。研究结果显示：垫状点地梅的各分枝每年均生长一个节间，呈辐射生长的各分枝簇在同一年生长的节间构成了垫状点地梅植株的“年轮”，垫状体任一分枝簇的单向节间数即为该植株的年龄；幂函数模型可以较好地表达植株径向生长与年龄之间的相关关系，年龄对垫状点地梅长轴长度、短轴长度和表面积变化的解释率分别为88.5%、87.5%和88.2%；垫状点地梅植株高度的年增量较小，平均年生长率仅为0.202 cm/a；其生物量积累随年龄的变化可用幂函数模型表达，年龄对地上生物量和总生物量变化的解释率分别为82.2%和83.9%。%Androsace tapete is one of the most typical cushion plants growing in the Tibetan Plateau. The establish-ment of its age is conducive to revealing the growing patterns,population structure and population dynamics of the cushion plant. By analyzing the architecture,phenological phases and sampling time of Androsace tapete compre-hensively,an exploratory method to eatablish the individual age of the cushion plant was found. Then we investiga-ted and analyzed its growing patterns based on the reliable age of 17 sampling plants. The study shows that the branching patterns of the cushions can indicate the age of the individuals which is equivalent to the number of inter-nodes in one single branchlet. The internodes which sprout in the same year constitute an annual ring. Power mod-els can properly describe and reveal the axial growth patterns with age in which 88 . 5% variation of major axis length,87. 5% minor axis length and 88. 2% surface area can be explained by the factor age seperately. As with other cushion plants,the height of Androsace tapete changes little with the mean growth rate only about 0. 202 cm/a. Moreover,correlations between biomass and age can also be revealed by power models well in which the factor age can account for 82 . 2% variation of the above-ground biomass and 83 . 9% variation of the total biomass respec-tively.
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