Abstract: Dacrydium pectinatum is one of the symbolic species in tropical mountain rain forest in Hainan Island and one of the key species to maintain the natural communities in that region. Based on the survival theory and point pattern analysis, we analyzed the demographic structure, spatial distribution characteristics and interspecies relationships of D. pectinatum. The results showed that: 1) The tree number for each age class of the D. pectinatum population showsed that the mortality in the first period of life stage is high, and the population is relatively stable in the middle period, after which the mortality increases gradually. 2) The survival curve of D. pectinatum population changes greatly. The population mortality and disappearance rate are higher in Ⅰ~Ⅴ age classes, showing the form of DeeveyⅢ; in the Ⅶ~ⅩⅦ age classes, the survival curve shows the form of Deevey-Ⅰ. 3) In the range of the study scale, there is an obvious difference in the spatial distribution of D. pectinatum at different life stages. The individuals perform aggregation distribution at small and medium scales in the early and middle periods of life stages, however, the aggregation intensity gradually is weakened with the increase of scale and age, from a clumped to a random pattern as trees grow from young to middleaged to old trees. In the later period of life stage, individuals show random distribution at the entire study scale. 4) The spatial association among different life stages is not significant, and most of them exhibit no correlation.

Key words: Pinus tabuliformis, net primary productivity, climate change., LPJ-GUESS model