浙江天目山苦槠种群结构和动态研究

Structures and Dynamics of Castanopsis sclerophylla Population in Tianmu Mountain of Zhejiang Province

选取了6个代表性样地对浙江天目山的苦槠种群结构和动态进行了研究,研究结果表明:苦槠种群的结构为衰败型:种群结构存在着幼龄种苗数量较少,部分样地有缺失现象。种群结构总体分布格局为随机型,不同阶段幼苗—幼树—中树—大树动态格局趋势表现为聚集—聚集—随机过渡—随机型。造成这种现象的原因一方面是由于大量的结实种子易被啮齿类捕食所致;另一方面也与苦槠的生物学特性和生境密切相关。苦槠种群维持和更新繁殖方式的适应性特点表现为无性萌生繁殖贡献率远远大于有性繁殖,种群主要通过萌生的方式来维持种群的更新和存活,并在一定程度上影响了演替的方向。衰败型苦槠种群的生态恢复可通过控制鼠害和移栽幼苗的策略。

The population structures and dynamics of Castanopsis sclerophylla were studied from six sampling plots in Tianmu Mountain in Zhejiang province. The results showed that all the populations of C. sclerophylla were spindle type. The age of structure of populations was declining due to lacking seedling and sapling. The overall population distribution followed a random type. Population dynamics analysis showed the spatial distribution pattern changed from aggregate type to random type during the course of population growth. One reason is that scores of seeds from populations were eaten by rodents, the other reason is that the patterns were not only closely related to the ecological and biological characteristics of each species and the relationships of competitive exclusion among them, but also to the environment. The characteristics of population reproductive mode are that the contribution rate of asexual reproduction is far greater than sexual reproduction. Maintenance and natural regeneration of C. sclerophylla populations adopted mostly sprout regeneration. To a certain extent, it affects the direction of succession. C. sclerophylla populations should restore the ecological balance through controlling rodents and transplanting seedling.