Abstract: [Objective] Interspecific associations of dominant plant populations respectively in the layers of tree, shrub and herb in communities of secondary natural forest of Syzygium odoratum in tropical coast were studied to reveal the inherent linkages of interactions among different populations during the process of community development, and to clarify the natural rules of community development in relation to the succession and interspecific association, as well as to provide a theoretical basis for the recovery of coastal forests in China.[Method] Typical communities of secondary natural forest of S. odoratum in Hainan Island were selected for the study. 2×2 contingency tables of species presence/absence data were used as the basis for the analysis of overall interspecific associations among dominant plant populations in different layers of tree, shrub and herb by using the variance ratio method.χ2 test and Ochiai index were used to characterize interspecific associations.[Results] Interspecific association in the tree layer was not significantly positive. For the 171 tree species, although there were collocation at some degrees, but a stable and harmonious collocation was not found. S. odoratum was not associated with other tree species. It was strongly independent. The inter-specific association of Casuarina equisetifolia and Pittosporum tobira were in significant positive correlation. The shrub layer displayed significant positive correlation in the inter-specific association (P<0.05). Compared with the tree layer, inter-specific association in the herb layer was strongly negative.[Conclusion] In the tropical coastal forest community, dominant species of displayed significant interspecific association and there existed a certain degree of independence between species and overall trend of stable development. In order to speed up the process of succession of the tropical coast secondary forest, the species with strong coupling should be protected in practice.

Key words: tropical coast, interspecific association, variance ratio, dominant population, secondary forest, Syzygium odoratum