摘要
狭叶坡垒(Hopea chinensis)是我国热带季节性雨林的代表性树种之一,目前仅零散分布于广西十万大山,但由于人类生产活动及乱砍滥伐而遭到严重破坏。作者对十万大山狭叶坡垒的生存环境、分布状况、种群结构及分布格局进行了调查,并对迁地保存的狭叶坡垒定期观测其物候及生长特征,采集种子进行了繁育研究,并在此基础上分析了狭叶坡垒的致濒原因。结果表明:(1)狭叶坡垒种群结构整体上为增长型,有些样地为稳定型;空间分布格局表现为集群分布,随着径级增大,其分布格局由集群分布向随机分布过渡;(2)个体间以种内竞争为主,幼苗幼树之间竞争高于成年树之间的竞争,种内竞争高于种间竞争;(3)狭叶坡垒生长缓慢,且主要集中在夏季,不同栽培地区的植株开始开花结果时间也不同。(4)种子无休眠期且寿命短,保湿及低温条件可以延迟种子的萌发时间。人类活动导致的种群数量下降和生境丧失是致濒的主要原因之一,种子寿命短及生长缓慢是其遭破坏后难以恢复的主要原因。
Hopea chinensis, an important species of seasonal rainforests, is well-known for its timber quality and has a scattered distribution only in Shiwandashan Mountain of Guangxi. To obtain basic information of H. chinensis, we carried out field surveys on the geographic distribution, population structure, and biological characteristics related to phenology. Meanwhile, seeds of H. chinensis were collected for germination and growth experiments. In addition, we briefly discussed the factors causing this species to be endangered and put forward likely conservation strategies. The results indicated that H. chinensis showed a population growth form in general, but being stable in some studied sites. The size distribution of the natural population presented a clumped pattern and shifted to a random pattern with the increase of size classes. The competition in seedlings and saplings of H. chinensis was more intensive than that in adults. And intraspecific competition contributed higher to the total competition index （CI） than interspecific competition. The seedlings of H. chinensis growed slowly and the fast growth rate occurred in the rainy season. Moreover, the onset for seedlings to begin flower and set fruits was different in different cultivated sites. Seeds of 14. chinensis are not easily to be preserved because of germination in a short time after maturity. We concluded that suitable habitat loss and accordingly decrease of the population size and scale resulted from human activity were the main factors responsible for the endangerment of H. chinensis. Intensively, short seed life span and slow growth could account for low restoration rate of H. chinensis once degraded.
出处
《生物多样性》
CAS
CSCD
北大核心
2008年第1期15-23,共9页
Biodiversity Science
基金
中国科学院知识创新工程项目
广西科学基金项目(桂科自0728168)
