9405933 Hubbell Previous research has measured the strength of density- and frequency-dependence in regulating individual tree species populations and in maintaining tree species diversity in Barro Colorado Island forests. The results of these analyses were restricted to trees >1 cm in diameter, yet this age class is likely to miss the important interactions that occur in the seedling and sapling layers of the forest. The empirical nature of this study will capitalize on a 50 ha plot of tropical forest that has previously been mapped and censused in 1982, 1985, and 1990. This study will provide the 1995 recensus of the 50 ha plot and begin a long-term analysis of seedling and sapling populations. %%% This study will provide the first comprehensive analysis of density- and frequency-dependence in seedling and sapling populations of a tropical forest. The detailed analyses of the dynamics of seedlings and saplings of tropical tree species will provide valuable empirical data on the mechanisms that maintain tree species richness in tropical forest ecosystems.
