Abstract: The season structure of tropical rain forest regions in Southern Yunnan has a significant difference with the climate structure of typic tropical rain forest. It has five season stages with different combinations of drought, humidness, cold and hotness. Therefore, tropical forest in Southern Yunnan although has the fundamental characteristics of tropical rain forest, yet exhibits significant variances and distinct season phases in particular. Such a kind of rain forest with seasonal features is called chinese type seasonal rain forest. Under the influence of this climate rhythm, the introduced Brazilian rubber tree exhibits some new characteristics.

Key words: Community, Biomass, Net production