| Title | Retrieving the gap fraction, element clumping index, and leaf area index of individual trees using single-scan data from a terrestrial laser scanner |
| Authors | Li, Yumei Guo, Qinghua Su, Yanjun Tao, Shengli Zhao, Kaiguang Xu, Guangcai |
| Affiliation | Chinese Acad Sci, Inst Bot, State Key Lab Vegetat & Environm Change, Beijing 100093, Peoples R China. Univ Chinese Acad Sci, Beijing 100049, Peoples R China. Univ Calif Merced, Sch Engn, Sierra Nevada Res Inst, Merced, CA 95343 USA. Peking Univ, Coll Urban & Environm Sci, Dept Ecol, Beijing 100871, Peoples R China. Peking Univ, Minist Educ, Key Lab Earth Surface Proc, Beijing 100871, Peoples R China. Ohio State Univ, Sch Environm & Nat Resources, Ohio Agr Res & Dev Ctr, Wooster, OH 44691 USA. |
| Keywords | Destructive sample Extinction coefficient Single scanning Terrestrial laser scanning Riegl VZ-400 GROUND-BASED LIDAR HEMISPHERICAL PHOTOGRAPHY ANGLE DISTRIBUTION FOREST STRUCTURE PLANT CANOPIES BOREAL FORESTS STANDS ARCHITECTURE DERIVATION DENSITY |
| Issue Date | 2017 |
| Publisher | ISPRS JOURNAL OF PHOTOGRAMMETRY AND REMOTE SENSING |
| Citation | ISPRS JOURNAL OF PHOTOGRAMMETRY AND REMOTE SENSING.2017,130,308-316. |
| Abstract | Terrestrial laser scanning (TLS) is a promising tool for estimating leaf area index (LAI). However, very few studies have considered the effect of clumping index Omega in the calculation of "true" LAI. In this study, we developed a new point cloud slicing method based on different incident zenith angles 0 and retrieved the gap fraction using multiple-return information to obtain more accurate "true" LAI estimations. In addition, we described a new Omega retrieval method based on the gap size analysis theory to correct the effect of foliage occlusion. Ground validation data were collected by destructively sampling 35 trees and measuring all their leaves. Results show that the TLS-based "true" LAI estimations based on a single TLS scan are strongly correlated with the destructively sampled LAI measurements (R-2 = 0.76, RMSE = 0.47). Moreover, our Omega retrieval method can effectively correct the effect of foliage occlusion. Other factors, such as the slicing resolution, percentage of laser beams with multiple returns, and scanning distance, have little effect on the final LAI estimation. (C) 2017 International Society for Photogrammetry and Remote Sensing, Inc. (ISPRS). Published by Elsevier B.V. All rights reserved. |
| URI | http://hdl.handle.net/20.500.11897/471738 |
| ISSN | 0924-2716 |
| DOI | 10.1016/j.isprsjprs.2017.06.006 |
| Indexed | SCI(E) |
| Appears in Collections: | 城市与环境学院 地表过程分析与模拟教育部重点实验室 |
