Spectral characterization of fire affects in Savanna Woodland, Northern Australia
Typically, classification of a landscape phenomenon such as the severity with which fire affects the vegetation is mapped through acquiring a satellite image from specific satellite based sensors and attempting to discern sub-classes of that phenomenon. Firstly by discriminating patches of fire affected areas and then by looking for spectral variation within these patches to describe the type of severity.
A ground based approach measures variation within the phenomenon to be described, in the case of fire severity, it measures the degree to which fire has affected the vegetation, and correlates this with a measurement of the spectral output from this same area by using a spectro-radiometer positioned, in the case of measuring fire severity, above the fire affected area, in a cherry picker or helicopter.
In this methodology, a ground sampling technique has been employed that describes the affects of recent fire on the vegetation by measuring the proportions of green, scorched and charred leaves, the woody material, bare soil and ash, in each of the strata and the overall scorch and char heights of tropical savanna woodland sites in northern Australia. Spectral reflectance, from 400 to 2500 nm, is measured from a helicopter and cherry picker over the same sites to determine indices, within the atmospheric windows of the electromagnetic spectrum, that discern the various fire affects, which may then be applied to any satellite sensor capable of sensing the appropriate wavelengths