Biodiv Sci ›› 2023, Vol. 31 ›› Issue (11): 23216.  DOI: 10.17520/biods.2023216

• Special Feature: Semi-humid Evergreen Broad-leaved Forests • Previous Articles     Next Articles

Vertical structural characteristics of a semi-humid evergreen broad-leaved forest and common tree species based on a portable backpack LiDAR

Jiesheng Rao1, Tao Yang1, Xi Tian1, Wencong Liu1, Xiaofeng Wang1, Hengjun Qian1, Zehao Shen1,2,*()   

  1. 1 School of Ecology and Environmental Science, Yunnan University, Kunming 650091
    2 Key Laboratory of MOE for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871
  • Received:2023-06-25 Accepted:2023-08-24 Online:2023-11-20 Published:2023-09-18
  • Contact: * E-mail: shzh@urban.pku.edu.cn

Abstract:

Background & AimsThe vertical structure of a forest is the vertical arrangement of aboveground vegetation elements. This feature of the forest affects plant and animal diversity and ecosystem function, and thus has been the focus of many plant ecologists. The development of portable backpack LiDAR technology allows for scanning of 3D forest structure over a large area with high precision. The purpose of this study is to explore the vertical structural characteristics of the semi-humid evergreen broad-leaved forest in Jizu Mountains on the scale of plot and individual tree.

Methods: The most important parameters of the vertical forest structure are: the canopy height (CH), the leaf area index (LAI), and the characteristics of individual tree. The CH directly reflects the biomass and the LAI represents photosynthetic capacity of plants. Based on a portable backpack LiDAR, the CH and LAI of a 20.16 ha semi-humid evergreen broad-leaved forest dynamics plot in the Central Yunnan Plateau were carefully scanned and quantitatively analyzed. On the basis of topographic correction and community classification, the vertical change and horizontal pattern of the LAI of the forest community were extracted and analyzed, and the parameters of single tree morphology and vertical structure of common tree species were surveyed quantitatively.

Results: The results showed that: (1) the distribution of CH and LAI in a 20 m × 20 m square was close to a normal distribution; (2) according to the vertical distribution of LAI, the canopy of the large plot can be divided into four layers: the upper canopy, the middle canopy, the lower canopy, and the shrub layer; (3) the vertical variation of LAI of the Castanopsis orthacantha community and the C. delavayi community showed a single-peak pattern with peak heights of 15 m and 13 m, respectively, and that of the Pinus yunnanensis community showed a double-peak pattern with peak heights of 5 m and 10 m; (4) the parameters of different tree species showed great variation, but the value of crown area/diameter was relatively uniform.

Conclusion This is the first study in China to quantitatively analyze a 3D pattern of LAI for a semi-humid evergreen broad-leaved forest with a complex structure based on LiDAR technology. This work may provide a useful database for future studies of forest biodiversity of this type and for comparative studies between different forest types.

Key words: semi-humid evergreen broad-leaved forest, vertical structure, leaf area index, canopy height, the portable backpack LiDAR, individual tree