3-D mapping of a multi-layered Mediterranean forest using ALS data

详细信息	查看全文 | 推荐本文 |

• 作者：Antó ; nio Ferraz^a ; ^b ; ^c ; ^{antonio.ferraz@ign.fr} ; Fré ; dé ; ric Bretar^d ; Sté ; phane Jacquemoud^b ; Gil Gonç ; alves^c ; ^e ; Luisa Pereira^f ; Margarida Tomé ; ^g ; Paula Soares^g
• 关键词：Airborne laser scanning ; LiDAR ; Multi-layered forest ; Unsupervised segmentation ; Mean shift algorithm ; Fuel mapping ; Vertical stratification ; Tree crown ; 3-D mapping ; Ground vegetation ; Understory ; Overstory
• 刊名：Remote Sensing of Environment
• 出版年：2012
• 期刊代码：79_00344257
• 类别：ear
• 出版时间：June, 2012
• 卷：121
• 期：Complete
• 页码：210-223
• 文件大小：2838 K

摘要

This study presents a robust approach for characterization of multi-layered forests using airborne laser scanning (ALS) data. Fuel mapping or biomass estimation requires knowing the diversity and boundaries of the forest patches, as well as their spatial pattern. This includes the thickness of the main vegetation layers, but also the spatial arrangement and size of the individual plants that compose each stratum. In order to decompose the ALS point cloud into genuine 3-D segments corresponding to individual vegetation features, such as shrubs or tree crowns, we apply a statistical approach based on the mean shift algorithm. The segments are progressively assigned to a forest layer: ground vegetation, understory or overstory. Our method relies on a single biophysically meaningful parameter, the kernel bandwidth, which is related to the local forest structure. It is validated on 44 plots of a Portuguese forest, composed mainly of eucalyptus (Eucalyptus globulus Labill.) and maritime pine (Pinus pinaster Ait.) trees. The number of detected trees varies with the dominance position: from 98.6%for the dominant trees to 12.8%for the suppressed trees. Linear regression models explain up to 70%of the variability associated with ground vegetation and understory height.