On the estimation of above ground biomass from ALOS PALSAR backscatter data for forests and woodlands in Australia

Focusing on woody vegetation in Queensland, Australia, a recent study (Lucas et al., 2010) established that the relationship between Advanced Land Observing Satellite (ALOS) Phased Array L-band SAR (PALSAR) HH and HVbackscattering coefficient (gamma0;γo) and above ground biomass (AGB)varied as a function of surface moisture conditions and vegetation structure. Inthis paper, the implications of the study for mapping AGB across Queenslandusing these data are discussed and a preliminary statewide map of AGB basedon a single equation for all structural types is presented. However, options forproviding a more robust estimate of AGB from these data are proposed, forQueensland but also for the other States. These include giving consideration todifferent forest structural types, the use of multi-annual ALOS PALSAR dataacquired during relatively dry conditions, inclusion of Landsat-derived FoliageProjected Cover (FPC) and/or ICESat GLAS data and non-linear inversion. Inall cases, reference to other ancillary information (e.g., climate datasets andsoils, geology and urban layer datasets) is essential. The use of ALOS PALSARand Landsat FPC is also advocated for detecting change in AGB because of theavailability of these data sets on at least an annual basis