亚热带森林蕨类植物生物量分配策略的海拔适应性

Altitudinal Adaptation of Biomass Allocation of Ferns in Subtropical Forests

为揭示蕨类植物生物量分配策略,本文以浙江金华山蕨类植物为研究对象,沿海拔梯度进行取样,分析蕨类植物在不同器官(根、根状茎、叶)的生物量分配特征,并进一步探讨各器官生物量分配权衡的海拔变化规律以及温度、光照适应性。结果显示:1) 生物量在不同器官的分配格局表现为根状茎 > 叶 > 根,根状茎生物量占比最大,是叶与根的2~7倍;2) 随着海拔上升,叶、根以及根状茎生物量没有发生显著变化;3) 随海拔上升和温度下降,根状茎生物量占比逐渐增大,叶、根的生物量占比逐渐减小;生物量分配权衡与林冠层盖度(光照)没有关系。以上结果表明,蕨类根状茎的储存功能可能是蕨类植物适应海拔环境变化的重要策略。

This study takes ferns from Jinhuashan in Zhejiang as the research object, and reveals the biomass allocation strategy and the environ-mental adaptability of underground storage organs of ferns. Sampling was carried out along the al-titude gradient to analyze the biomass allocation characteristics of ferns in different organs (roots, rhizomes and leaves), and to further explore the altitude variation patterns of biomass allocation and temperature and light adaptations of each organ. The results showed that: 1) The patterns of biomass allocation in different organs showed that rhizomes > leaves > roots, and rhizome biomass accounted for the largest proportion, which was 2~7 times that of leaves and roots. 2) Biomass of roots, leaves and rhizomes did not change significantly with increasing altitude. 3) With the in-crease of altitude and the decrease of temperature, the biomass proportion of rhizomes gradually increased, and the biomass proportions of leaves and roots gradually decreased. The biomass allo-cation strategy was not related to canopy cover (light). The storage function of fern rhizomes may be an important strategy for ferns to adapt to altitude changes.