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为了解贵阳青桐种群生命过程,对贵阳市云岩区相宝山青桐树林进行调查和数据统计,编制相宝山青桐种群的生命表,分析其的生存率、危险率、积累死亡率和死亡密度等生存函数的曲线变化,进而得出青桐种群动态趋势,研究结果表明:青桐种群10年以前存活数急剧下降,死亡率达97.5%后期趋于稳定,存活曲线趋于DeeveyⅢ型。生存函数分析表明,青桐树林的生存率为单调下降,而积累死亡率为单调上升,其整体的变化幅度为后期低于前期。死亡率曲线与损失度曲线变化一致,青桐种群生长过程中出有两次死亡高峰期。
In order to understand the life process of M. involucrata population in Guiyang, the life table of Xiangtongbaqingbaotong in Xiangbaoshan was prepared through surveys and statistics on the Xiangbaoshan shady trees in Yunyan district of Guiyang, and its survival rate, risk rate, accumulated mortality and death density were analyzed The results showed that the survival rate of M. chinensis population dropped sharply 10 years ago, the mortality rate reached 97.5%, the latter tended to be stable, and the survival curve tended to Deevey Ⅲ type. Survival analysis showed that the survival rate of M. alba forest decreased monotonically, while the cumulative mortality rate increased monotonically. The overall variation range was lower than the previous period. Mortality curve and loss curve changes consistent with the growth of M. involutic population there are two death peaks.