Influence of forest disturbances on backscatter of the airborne L-band synthetic-aperture radar in a larch forest in northern Japan
October 29th, 2011
Atsuhiro Takahashi, Hiroyuki Oguma, Masanobu Shimada, Manabu Watanabe, Yasumichi Yone and Nobuko Saigusa
Release Date: October 29, 2011
Influence of forest disturbances on backscatter of the airborne L-band synthetic-aperture radar in a larch forest in northern Japan
Atsuhiro Takahashi1), Hiroyuki Oguma2), Masanobu Shimada3), Manabu Watanabe3), Yasumichi Yone4) and Nobuko Saigusa1)
1) Center for Global Environmental Research, National Institute for Environmental Studies
2) Center for Environmental Measurement and Analysis, National Institute for Environmental Studies
3) Earth Observation Research Center, Japan Aerospace Exploration Agency
4) Faculty of Life and Environmental Science, Shimane University
(Received: June 16, 2011)
(Accepted for publication: October 5, 2011)
Abstract:
This paper is a case study on the detection of forest disturbances in airborne synthetic-aperture radar (SAR) data. We investigated changes in the L-band SAR backscattering coefficient (σ0) following thinning and a typhoon in a larch forest in northern Japan. The thinning caused changes of intermediate magnitude in the above-ground biomass (AGB), whereas the typhoon broke or uprooted most of the trees, thereby significantly changing the forest structure without changing the biomass. Thinning led to back-scattering coefficients change of less than about 1 dB; HV polarization was most sensitive to the change in AGB, and HH was insensitive to it. In the case of the typhoon, VV was sensitive to the change in forest structure, whereas HH and HV were insensitive to it, suggesting that the tree trunks, which were felled in one direction by the typhoon, enhanced the backscattering signal of the polarisation that accorded with the trunk direction.
To cite this article:
Atsuhiro Takahashi, Hiroyuki Oguma, Masanobu Shimada, Manabu Watanabe, Yasumichi Yone and Nobuko Saigusa: “Influence of forest disturbances on backscatter of the airborne L-band synthetic-aperture radar in a larch forest in northern Japan”, Hydrological Research Letters, Vol. 5, pp.64-68, (2011) .
Copyright (c) 2011 Japan Society of Hydrology and Water Resources