Abstract: Plant community composition and species diversity were described in the different cultivation intensities of bamboo forest in Fujian Wuyishan National Nature Reserve. The data was compared with that of three types of natural vegetation(evergreen broad-leaved forest, coniferous and broad-leaved mixed forest, bamboo and coniferous/broad-leaved mixed forest). The results showed that great composition changes of the tree layer, the shrub layer and the herb layer were observed at different stages of bamboo cultivation, which involved the loss of many species in the tree layer such as Fagaceae, Lauraceae and Pinaceae. Species diversity of the tree layer decreased, while those of the shrub layer and herb layer increased differently along with the purified stages of bamboo cultivation. Species diversities of the shrub layer and herb layer were greatly influenced by the tree layer. β diversity corresponded to the change rate of species along the cultivation intensity gradient of bamboo forest. The lowest value of Sorenson index and the highest value of Cody index of the tree layer were recorded from type Ⅱ of the bamboo mixed forest(c, 25% ≤ bamboo < 50%)to type Ⅰ of the bamboo mixed forest(b, 50% ≤bamboo < 75%). Most of the tree species had lost their distribution during this stage. To this point of view, it is very important for the Reserve to take action to protect the species diversity and control the loss of tree species before the stage of occurrence.

Key words: Combined pollution, Interaction, Mechanism