Effects of litter thickness on leaf litter decomposition and enzyme activity of three trees in the subtropical forests Nutrient resorption in the leaves of two leguminous species widely planted in South China The Mossflora of Mt. Jiuwan, Guangxi and Its Significance in Dividing the Boundary Line Between Tropical and Subtropical Regions in China (To be continued) Litter decomposition of six common tree species at different rainy periods in the subtropical region The influence of acid rain on the leaf litter decomposition of three dominant trees in the subtropical forests