Abstract:

Tropical rain forests are currently distributed in the southeastern Xizang, southern Yunnan, southern Guangxi, southern Taiwan, and Hainan Island in China. The ecological physiognomy, species composition and diversity of the tropical rain forests were reported in literatures, however with different terms for different regions of China, due partly to different methods, definitions and references used. In this review article, we summarize current research status and main questions on the phytosociological characteristics of the tropical rain forests in China, to provide information for further studies, protection and management. The lowland tropical rain forests in China belong to the northern marginal type of the southeastern Asian lowland rain forests, and share the similar community structure, physiognomy, and species diversity with other subtypes of the southeastern Asian lowland rain forests. Distributed in the northern edge of the monsoonal tropical zone, the lowland tropical rain forests in China are limited by seasonal drought and insufficient amount of heat, which is usually demanded by typical tropical rain forests, and therefore were given the name “tropical seasonal rain forest” by Chinese researchers. They are different from the typical humid or wet tropical rain forests in that they include a certain proportion of deciduous trees in canopy, less megaphanerophytes and epiphytes, but more lianas and microphyllous species in tree leaf sizes. The tropical rain forests in China show different floristic composition in different regions. Specifically, they contain less typical tropical floristic components, and show a transition to the tropical lower montane forests in southwestern China, and to the subtropical evergreen broad-leaved forests in south China. They show similar community structure and ecological physiognomy in Yunnan and Guangxi. Furthermore, the tropical seasonal rain forest in Yunnan contains dipterocarp trees and has the highest proportion of tropical Asian floristic components among the tropical rain forests in China and show the similar community structure characteristics as the lowland tropical rain forests in the Southeast Asia, although occurring on a higher altitude (up to 1 100 m above sea level, can reach up to 1 300 m in some certain areas). We further discuss the uncertainty and confusion in definition, classification and description of the tropical rain forests from literatures in different regions of China and propose to give a consolidated consideration on the definition and classification of the tropical rain forests in China.

Key words: tropical rain forest, classification, ecological physiognomy, ecological structure, floristic composition, species diversity, China