Jr. Baker et al., RELATIONSHIPS BETWEEN PHYSICAL CHARACTERISTICS AND POLARIMETRIC RADARBACKSCATTER FOR CORSICAN PINE STANDS IN THETFORD FOREST, UK, International journal of remote sensing, 15(14), 1994, pp. 2827-2849
Global monitoring of forest extent and changes of extent with time are
vital not just to provide a continuous assessment of a renewable reso
urce essential to mankind but also to give an input to models of the g
lobal carbon cycle and of climate change. Microwave remote sensing is
a potential means to accomplish this objective. However, to determine
the optimum characteristics of a satellite synthetic aperture radar (S
AR) for reliable forest monitoring it is first necessary to validate m
odelled microwave backscatter relationships in studies of relatively s
mall areas using data from aircraft SAR systems and from detailed grou
nd survey. The Maestro 1 Campaign provided fury polarimetric SAR data
in three wavelengths together with a large set of ground data for Thet
ford Forest. Calibrated microwave responses were averaged for more tha
n 300 stands, primarily of Corsican pine. A georeferenced database for
the test site was built up from these mean responses combined with in
formation on planting date, species and, for those stands fully sample
d, characteristics such as height and timber volume. The radar backsca
tter at P and L bands, expecially the cross-polarized responses, corre
late well with volume. An analysis is made of the accuracy with which
regression models can be used to predict timber volume over larger are
as around the test site. The precision of this prediction can be impro
ved by fuller use of the information contained within the measured dat
a, specifically in the correlation between the HH and VV returns, and
by the fuller use of theoretical models, which consider more comprehen
sively the complete polarimetric backscatter mechanisms relevant to th
e response of stands.