Plant flora of tropical ravine forest in Hainan Island

The tropical ravine forest of Hainan Island is rich of plant species. We investigated the plots of 5 000 m2 in Bawangling and Limushan natural reserve. 703 trees were recorded. Both areas had common species of 36 families, of which Lauraceae, Apocynaceae, Euphorbiaceae, Meliaceae, Symplocaceae and Myrtaceae occupied over 60%, indicating that the two samples had high similarity. Trees in the tropical distribution type were dominant in Bawangling and Limushan ravine forest. In Bawangling ravine forest, the tropical components of family accounted for 85.4%, components of genus accounted for 78.5%, while in Limushan ravine forest, components of family accounted for 88.9%, components of genus accounted for 92.6%. Tropical genera components of Limushan ravine forest were higher than that of Bawangling, it meant that Limushan ravine forest had stronger tropical nature.