关键词: Neocheiropteris palmatopedata, 生长特性, 孢子萌发, 竞争

Abstract

Neocheiropteris palmatopedata, a rare and endangered species endemic to China, has a scattered distribution only in Sichuan, Guizhou and Yunnan provinces. Declining rapidly in population size and on the verge of extinction, it was listed as a plant of second-class protection in The List of Chinese Urgently Protected Wild Plants. To explore endangerment mechanisms of N. palmatopedata, we investigated its population and community structure, germination and growth characteristics as well as soil properties of its habitat. Our results indicated that N. palmatopedata grew in primary evergreen broad-leaved, and mixed coniferous-broad-leaved forests. It was dominated by other species in the community. Spores germinated without a dormancy period and the germination rate was high, indicating that spore characteristics are not a factor causing its endangerment. However, N. palmatopedata required a long period of time to complete its life cycle under natural conditions. During this period, it was vulnerable to stochastic events such as drought, causing a low seedling survival rate. Although the species shows strong rhizome initiation, population growth is not affected by rhizome propagation. Soil property analysis showed that organic matter, potent Ca and availability of Mg were key factors for growth and development of N. palmatopedata. In conclusion, narrow bioecological characteristics led to lowered survivorship and contribute to the endangerment of N. palmatopedata. Human-induced habitat loss and accompanying habitat fragmentation likely accelerated the endangerment process. Our results could provide a theoretical basis for the effective protection of this species.

Key words: Neocheiropteris palmatopedata, growth characteristics, spore germination, competition