Flowering and Fruiting Phenology of Woody Trees in the Tropical-Seasonal Rainforest, Southwestern China

The reproductive phenology of tropical plants is potentially driven by a number of abiotic and biotic factors. However, it is still unclear as to which climatic factors and biotic interactions drive the reproductive phenology of woody trees in the tropical seasonal rainforest of Xishuangbanna region in Southwest China. We conducted observations on woody plants (including trees and shrubs) phenology between November 2004 and October 2007 at biweekly intervals in the one hectare permanent plot of tropical seasonal rainforest in Southwest China. A total of 357 individuals of 76 species (70 genera, 37 families), comprising of 59 (78%) woody trees and 17 (22%) shrub species were observed. Our results demonstrate that flowering and fruiting frequencies show slight temporal variation between years. Flowering was significantly correlated with day-length, temperature and rainfall and fruiting was significantly correlated with rainfall and temperature. This finding indicates that woody tree reproductive phenology was primarily associated with temperature and rainfall and to a lesser extent with day-length. Reproductive phenology is also linked to seasonal patterns with flowering peaking in the late dry season and fruiting peaking in the late wet season. Moreover, reproductive phenology is also significantly associated with reproductive ecological guilds such as pollination types and dispersal modes. Community reproductive phenology is associated with climatic seasonality and biotic interactions. It also suggests that seasonal phenology patterns may play a fundamental role in community reproductive success in the tropical seasonal rainforest of Xishuangbanna region of Southwest China.