Abstract:The present hermatypic coral community is in fact composite of sites at different successional age.Based on the data collected from systematic sampling on the community, the composition of species,α-, β-diversity,their variations along envirgnmental gradients and the dynamics of species diversity were analyzed.Major conclusions from this research are:1.Sites in middle depth(2.5~5.0m)have significantly higher species diversity than other areas,which indicates that area in this depth is the optimum habitat fo...