The BEF- China experiment provides the opportunity to study the effects of tree layer diversity and composition on herb layer species richness, composition and invasibility in subtropical China. SP 11 studied the interaction between tree layer diversity, herb layer diversity and invasibility in highly diverse subtropical forests. Using observations and experimental approach, we investigated the impact of tree species richness on herb layer assembly and invasibility and quantified feedback effects of herb layer on growth and survival of trees. We use measurements of functional traits of herbaceous species and indices of functional diversity of the herb layer to predict invasibility by other plant species with particular functional traits and test if invasions will be complementary, i.e. increasing functional diversity in the herb layer. Additionally we focused on herb layer characteristics to use these variables as response variables to tree layer richness.

To characterize functional traits of the herb layer community, 5-10 individuals per species were randomly selected from the full area of Site A in Xingangshan. 100 common herb layer species could be recorded. For these individuals, the height, number of leaves, flowers / seeds were recorded during the period from 2010-08-20 to 2010-08-30. In addition, the dry weight of the aboveground biomass of the shoots and leaves were taken. From each of the three individuals, fully developped leaves were randomly sampled and fresh weight and dry weight were determined, separately for each leaf. SLA was determined by means of the program WinFOLIA PRO 2008; the C / N ratio of the leaves was calculated following measurements on the vario EL elemental analyzer at the Institute of Biology / Geobotany and Botanical Garden in Halle. Mean values were calculated for each individual and afterwards for each species.

Main experiment, Site A, no shrub VIPs 29°08'-29°11'N 117°90'-117°93'E

functional traits were recorded from 2010-08-20 till 2010-08-30

woody and herbaceous species of the herb layer community on Site A

Recorded functional traits are: individual height, number of flowers / seeds, number of leaves, SLA, LDMC, LMR and C / N ratio of leaves. For details see data group description.