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Research article - Peer-reviewed, 2000

Estimation of forest parameters using CARABAS-II VHFSAR data

Fransson JES, Walter F, Ulander LMH


The use of airborne CARABAS-II VHF (20-90 MHz) SAR data for retrieval of forest parameters has been investigated, The investigation was performed at a test site located in the southwest: of Sweden consisting mainly of Norway spruce forests. Regression models predicting forest parameters from radar backscattering amplitude were developed and evaluated. The results showed a linear relationship between backscattering amplitude and forest stem volume, stem diameter, and tree height. The analysis also showed that the radar signal is strongly affected by ground slope conditions. The root mean square errors from the regression analysis, restricted to forest stands on near-horizontal ground, were found to be 66 m(3) ha(-1), 3.2 cm, and 2.3 m for stem volume, stem diameter, and tree height respectively. No saturation of the backscattered signal was observed up to the maximum stem volume of 625 m(3) ha(-1), corresponding to a biomass of 375 tons ha(-1). The results imply that VHF SAR data have significant potential for operational use in forestry


CARABAS; SAR; VHF; forest parameter estimation

Published in

IEEE Transactions on Geoscience and Remote Sensing
2000, volume: 38, number: 2, pages: 720-727

Authors' information

Fransson, Johan
Swedish University of Agricultural Sciences, Department of Forest Resource Management
Walter, Fredrik
Ulander, Lars

UKÄ Subject classification

Forest Science

Publication Identifiers


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