特有濒危植物长柄双花木濒危原因及其保护对策

长柄双花木为我国特有二级重点保护濒危植物，主要分布于江西、湖南、浙江和广东等省的部分区域。本研究综合分析了长柄双花木的自然地理分布特征、群落学特征、生物学特性、繁殖生态学特征及其濒危的可能原因。导致长柄双花木濒危的原因主要有：（1）在有性生殖过程中，由于花粉和资源限制、花粉竞争、传粉昆虫缺乏以及有机养分积累不足等，导致其有性繁殖能力差，结实率和结籽率低。（2）自然条件下种子萌发困难，萌发率、成苗率。（3）克隆繁殖能力有限，自然种群中克隆个体稀少。（4）生境片段化导致种群缩小，更新困难。（5）严重人为干扰直接导致种群锐减。此外，本研究还从强化科学研究和和保护途径等方面探讨了其保护对策。

ENDANGERING REASONS AND CONSERVATION STRATEGY OF DISANTHUS CERCIDIFOLIUS VAR. LONGIPES,AN ENDEMIC PLANT TO CHINA

Disanthus cercidifolius vat. longipes, a plant species that only occurs in a few counties in Hunan, Jiangxi, Zhejiang and Guangdong Provinces and with relatively small numbers of individuals, is recorded as the 2nd Class endangered species for conservation in China. In this paper, the geographical distribution, community features, biological traits, reproductive ecology features and the endangering reasons of D. cercidifolius var. longipes are reviewed and analyzed. The endangering reasons of this species may be summarized as follows： Firstly, pollen and resource limitations to lifetime seed production, pollen competition, shortage of pollinators, and deficiency of organic nutrient may be the major factors leading to the endangered status of D. cercidifolius var. longipes. Secondly, there exist some barriers of its seed germination in natural conditions, which lead to the low germination rate and few seedlings. Thirdly, there are few ramet in its natural populations, because the clonal reproduction ability of this species is limited. Additionally, habitat loss, fragmentation and serious human disturbance lead to the number of populations declines directly and the individuals are difficult to regenerate. Moreover, some effective strategies for conservation of this species are discussed from the aspects of scientific research and conservation approach.