Danxia Mountain in Guangdong Province was investigated to inquire into the special ecological effects in ravines of Danxia Landform. The results showed that its geomorphologic ecological effects can be manifested in the following two aspects. Firstly, multitudinous ridgy stone peaks and hollow ravines were shaped in the forming process of Danxia Landform. Ecological factors were different between its ravines and other open regions. Relatively close microclimate and high moisture condition in ravines could provide suitable living environment for the tropical species which preferred to hot and humid environment. Ravine geomorphologic environment, like smooth degree of surrounding cliffs, would affect light intensity reflecting into ravines. All the aspects had influence on the temperature and humidity in ravines. Secondly, the special ravine ecological effects in Danxia Landform provided possibility for gestating a group of taxa with greater tropical characteristics. There tropical plant flora was markedly increased in compare with other vegetations on similar latitude. Tropical plant distributions were obvious in most ravines of Danxia Landform. Its proportion was 10% more than that of other regions on the similar latitude. The ravines in Danxia Landform were rich in liana, ferns and other high waterlogging resistance plants. Collectively the phenomena that some typical species in south subtropics appeared in midsubtropics revealed latitudinal shift of plant distribution. This kind of climax communities, which were coordinated and balanceable with their geomorphologic environments due to the special ravine ecological effects in Danxia Landform, could be called geoclimax communities.