青藏高原露蕊乌头不同海拔居群的开花持续期与繁殖分配

对青藏高原东部3个不同海拔居群的露蕊乌头(Aconitum gymnandrum)(毛茛科)开花持续期和繁殖分配进行了野外观察和检测试验。结果表明:(1)随着海拔的升高,露蕊乌头的开花持续期时间延长,且不同居群间存在显著差异。(2)露蕊乌头的植株个体越大,繁殖投入越高。(3)露蕊乌头的繁殖分配在地上总生物量中所占的比例随海拔升高而增加。研究认为,露蕊乌头在高海拔地区较高的繁殖分配比例强调了有性繁殖在高山恶劣环境中的重要性,而高海拔地区开花持续期的延长补偿了传粉昆虫的减少并增加了对传粉昆虫的吸引能力。

Flower Duration and Reproductive Allocation in Different Altitudinal Populations of Aconitum gymnandrum (Ranunculaceae)

We studied the flower duration and reproductive allocation of Aconitum gymnandrum in different altitudinal populations on the Northeast of the Qinghai-Tibetan Plateau.Our results showed that:(1)The duration of individual flower in the high altitudinal population was remarkably longer than those in low altitudinal populations,and there was significant difference in flower duration between populations.(2)The biomass of flowers increased with plant size in the three populations.(3)The proportion of flowers in the total above ground biomass (reproductive allocation) increased along the altitude gradient.Consequently,we concluded that the importance of sexual reproduction in alpine environment was emphasized by the increased allocation of biomass to flowers,and prolonged floral longevity of A.gymnandrum along the altitude gradient suggested the mechanisms of compensation for the reduced pollinator availability and attraction to pollinators.