Study on age structure and spatial distribution pattern of Sinojackia rehderiana population

The age structrue and spatial distribution pattern of population of endangered tree species Sinojackia rehderiana in Yongxiu，Northern Jiangxi Province were studied. The results showed that the age structure of the population reveraled a "reversed J" trend，which was a increasing one. The individual survival curve of the population was Ⅰ Deevey type，just convex tpye，which showed that young individuals were more likely to survive than adult ones. The static life table showed that there was no obvious regular pattern of mortality change from young individuals to the elderly，there may be some unknown biological factors，which resulted in the phenomenon. For the samples with high population density，the spatial distribution pattern was not obvious. For the samples affected a lot by human's activities and with a low population density，the spatial distribution pattern showed obvious cluster distribution. The age structure and spatial distibution pattern of population showed that，the living condition of S.rehderiana was affected by human's activity. The human's activity was an important factor restricting the development of population. So，ignoring the inner biological factors，reducing the impact of human's action on the species were important measures to protect the species.