新疆濒危野生樱桃李的种群结构与动态"

Population structure and its dynamics of wild Prunus divaricata in Xinjiang,Northwest China

为了解野生樱桃李种群结构和种群生态现状,采用"空间序列代替时间变化"的方法,对新疆天然分布区内的野生樱桃李不同种群的径级结构、冠幅结构及株高结构进行了分析,运用静态生命表描述了野生樱桃李种群年龄结构的动态变化规律。结果表明,樱桃李天然种群的株高和冠幅结构呈现为一定的衰退趋势,冠幅在总体呈现为近乎对数型的衰减趋势;种群的径级结构趋于稳定型,但种群结构表现出较强的波动性,种群衰退风险较高;同时,不同样地种群因所处微环境等的差异,在径级、株高和冠幅结构上表现出一定差异。野生樱桃李种群的存活曲线接近于B1型(台阶型),说明幼龄的死亡率较高,且不同生活史时期的死亡率差异较大。新疆的野生樱桃李天然种群表现出一定的不稳定性,亟待补充低龄级的个体,并减少对成年树的砍伐破坏,从而为种群的保育和恢复提供保障。

In order to understand the structure of the wild population and analyze its current survival situation, an investigation was conducted in the natural distribution region of Prunus divaricata population. Adopting space as a substitute for time, a comparative analysis was made on the ageclass, heightclass, and crown widthclass of the population, and the dynamics of the age structure of the population was described according to the static life table. The results showed that the structure of the crown widthclass and heightclass showed a certain degree of decline, and there was an overall logarithmic decline in crown widthclass. Due to the effects of different microenvironments among the plots, the population structure had definite difference. The survival curve fitted the B1 type （steptype curve）, indicating that the seedlings had a high mortality rate, and there were significant differences in the death rate at different life stages. The natural population of wild P. divaricata in Xijiang showed some unstable characteristics. Therefore, it is urgently needed to supplement seedlings or young individuals and to prohibit felling adult individuals so as to provide guarantee for the conservation and recovery of wild P. divaricata population.