The landcover change information required is that which results from landuse, and not climate or season. The latter driving forces produce changes in the physiological functioning of the vegetation, and these changes in activity and phenology can be successfully monitored using - a greenness index - the NDVI.

Landuse principally transforms the structure and floristic composition of landcover, with consequent changes in functioning. Therefore to detect and monitor landuse-driven landcover changes, satellite data must be converted into some index of structure or composition. A measure of functioning, such as the NDVI greenness index, will be unable by itself to separate landuse from season or climate as the causal factor.

The simplest but most powerful and widely applicable approach is to use two relationships simultaneously. The first is greenness. The second is to use a simple index of cover, the proportion of the landcover that is plant cover.

The greenness index is based on the contrast in reflectance in the red and near infrared wavebands shown by green actively growing vegetation. This greenness can be demonstrated in a False Colour Composite (FCC image) without computing the NDVI index.

The cover index is based solely on the contrast in reflectance in the visible wavebands of vegetation and the underlying soil. Most but not all soils found in Australia are more reflective (brighter) in the visible wavebands than vegetation, which is usually darker: this relationship holds whether the vegetation is green or dry. Thus, if the landcover of a pixel is cleared or reduced in biomass or cover, that pixel will increase in brightness in the visible wavebands. Depending on the amount of vegetation loss, it may or may not decline in greenness.