Abstract: Based on data from nine plots, we analyzed the population structure of Rhododendron taishunense, a plant endemic to East China, the niche characteristics and interspecific associations of the dominant species, aiming to provide a basis for effective protection and scientific management. The results showed that population age structure of R. taishunense generally exhibited a growing pattern. Some plots showed generational gaps due to digging or habitat destruction. In the tree layer, some species, such as R. taishunense, Castanopsis eyrei and Schima superba, showed clear advantages in niche breadth. In the shrub layers, C. eyrei, R. taishunense, and Lindera aggregata had relatively large niche breadths, indicating strong adaptability. R. taishunense overlapped with 17 species in the tree layer and 15 species in the shrub layer. The niche overlap values of dominant species in the tree and shrub layers were 0.17 and 0.15, respectively, indicating a high degree of niche differentiation, and potential competitive relationships. The tree layer showed no significant association, while the shrub layer showed a significant negative association. Association coefficients, co-occurrence percentages, Pearson and Spearman correlation coefficients showed that the proportion of species pairs with negative associations or no co-occurrence ranged from 60.8% to 76.6%, indicating strong interspecific competition. Although R. taishunense had strong ecological adaptability, its community was in a successional stage with poor stability. It is necessary to establish special protection areas and implement scientific management of seedlings to promote population development.

Key words: Rhododendron taishunense, population structure, ecological niche, interspecific association