Header

UZH-Logo

Maintenance Infos

Forest canopy gap fraction from terrestrial laser scanning


Danson, F M; Hetherington, D; Morsdorf, F; Koetz, B; Allgöwer, B (2007). Forest canopy gap fraction from terrestrial laser scanning. Geoscience and Remote Sensing Letters, 4(1):157-160.

Abstract

A terrestrial laser scanner (TLS) was used to measure
canopy directional gap fraction distribution in forest stands in the Swiss National Park, eastern Switzerland. A scanner model was derived to determine the expected number of laser shots in all directions, and these data were compared with the measured number of laser hits to determine directional gap fraction at eight sampling points. Directional gap fraction distributions were
determined from digital hemispherical photographs recorded at the same sampling locations in the forest, and these data were compared with distributions computed from the laser scanner data.
The results showed that the measured directional gap fraction distributions were similar for both hemispherical photography and TLS data with a high degree of precision in the area of overlap of orthogonal laser scans. Analysis of hemispherical photography to determine canopy gap fraction normally requires some manual data processing; laser scanners offer semiautomatic measurement of directional gap fraction distribution plus additional threedimensional
information about tree height, gap size, and foliage
distributions.

Abstract

A terrestrial laser scanner (TLS) was used to measure
canopy directional gap fraction distribution in forest stands in the Swiss National Park, eastern Switzerland. A scanner model was derived to determine the expected number of laser shots in all directions, and these data were compared with the measured number of laser hits to determine directional gap fraction at eight sampling points. Directional gap fraction distributions were
determined from digital hemispherical photographs recorded at the same sampling locations in the forest, and these data were compared with distributions computed from the laser scanner data.
The results showed that the measured directional gap fraction distributions were similar for both hemispherical photography and TLS data with a high degree of precision in the area of overlap of orthogonal laser scans. Analysis of hemispherical photography to determine canopy gap fraction normally requires some manual data processing; laser scanners offer semiautomatic measurement of directional gap fraction distribution plus additional threedimensional
information about tree height, gap size, and foliage
distributions.

Statistics

Citations

104 citations in Web of Science®
127 citations in Scopus®
Google Scholar™

Altmetrics

Downloads

116 downloads since deposited on 27 May 2009
18 downloads since 12 months
Detailed statistics

Additional indexing

Item Type:Journal Article, refereed, original work
Communities & Collections:07 Faculty of Science > Institute of Geography
Dewey Decimal Classification:910 Geography & travel
Language:English
Date:2007
Deposited On:27 May 2009 12:10
Last Modified:06 Dec 2017 19:38
Publisher:IEEE
ISSN:1545-598X
Additional Information:© 2007 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.
Publisher DOI:https://doi.org/10.1109/LGRS.2006.887064

Download

Download PDF  'Forest canopy gap fraction from terrestrial laser scanning'.
Preview
Filetype: PDF
Size: 1MB
View at publisher