资源环境科技发展态势分析平台

The hilly red soil region in southern China is still facing serious soil erosion, even after long-term afforestation projects. This might result from structural shortcomings of the tree species chosen for afforestation. Within the Biodiversity and Ecosystem Functioning China project (BEF China), we used point cloud data from terrestrial laser scanners (TLS) and splash cups to analyze spatial leaf area index (LAI) and to predict the potential of splash erosion in subtropical forests. High LAI of Lithocarpus glaber and Schima superba was measured mainly at the middle and lower parts of the trees while for Sapindus saponaria it was found at the upper parts. LAI was decreasing from the tree stems to the edges of the canopy. Lognormal and exponential linear models were suitable to describe the vertical and horizontal LAI distribution of selected tree species, respectively. Sapindus saponaria generally had the highest values of throughfall kinetic energy (TICE) among the analyzed tree species and measured rainfall events. In the radial direction, higher LAI tended to produce lower TKE, whereas in the vertical direction, higher skewness of LAI distribution had higher TKE. LAI and its spatial distribution both were important for TKE. These findings can help to understand mechanisms of splash erosion in forest plantations related to unsuitable spatial LAI of tree species planted. It might further improve our knowledge how tree diversity may influence splash erosion by enriching the canopy layers in an early successional stage of subtropical forest plantations.