Root-sprouting ability in an evergreen and deciduous broad-leaved mixed forest

As an important way for forest regeneration, root-sprouting plays an important role in maintaining population and species diversity. Using the initial census data of Badagongshan 25-hm2 forest plot, we analyzed the relationship between root-sprouting ability and topographic factors, and tested the phylogenetic signal of root-sprouting ability. We found that there are 33039 individuals with root-sprouts which account for 17.70% of all the individuals and the total number of root-sprouts was 54184. Results of Spearman's correlation analyses with torus-translation tests showed that the root-sprouting ability significantly negatively correlated with elevation, convex, and vertical distance from channel network. However it significantly positively correlated with topographic wetness index. These may be due to that the low valley areas were disturbed by the stream flow, thus accelerating the root-sprouting ability. The root-sprouting ability of 126 common species showed significant phylogenetic signal. It showed significant phylogenetic signal for shrub species and deciduous species but not for canopy species, sub-canopy species and evergreen species in different life forms. These suggested that root-sprouting ability was a very unstable functional trait in the evolutionary history. In conclusion, the root-sprouting ability of ligneous plants at Badagongshan plot was influenced by topographic factors and phylogenetic history.