TITLE:
Estimation of Tropical Forest Structural Characteristics Using ALOS-2 SAR Data
AUTHORS:
Luong Viet Nguyen, Ryutaro Tateishi, Hoan Thanh Nguyen, Ram C. Sharma, Tu Trong To, Son Mai Le
KEYWORDS:
Forest Structure, Forest Biomass, SAR, ALOS-2, Backscattering Intensity, Sensitivity Analysis
JOURNAL NAME:
Advances in Remote Sensing,
Vol.5 No.2,
June
27,
2016
ABSTRACT: The potential of ALOS-2 SAR data for the estimation of tropical forest structural characteristics
was assessed in Vietnam by collecting forest inventory data. The effect of polarization and seasonality
of the SAR data on the estimation of forest biomass was analyzed. The combination of HH,
HV, and HH/HV polarizations using multiple linear regression did not improve the estimation of
biomass compared to using the HV channel independently, as the HH and HH/HV variables were
not statistically significant. The dry season HV backscattering intensity was highly sensitive to the
biomass compared to the rainy season backscattering intensity. The SAR data acquired in the
rainy season with humid and wet canopies was not very sensitive to the biomass. The strong dependence
of the biomass estimates with the season of SAR data acquisition confirmed that the
choice of right season SAR data is very important for improving the satellite based estimates of the
biomass. The validation results showed that the dry season HV polarization could explain 54%
variation of the biomass.