Comparison of methods

The differences that exist between what is described as homogenous 'bare ground' in the CSIRO model of pattern and what is recorded in the autocorrelation model as being highly variable can be explained by the results of field investigations.

These showed that the bare ground class is actually a mixture of tussocks of grass or small, close to the ground patches of grass species interspersed with bare ground. Therefore, the spectral response from remote sensing is expected to be mixed for this area. KS1 was also shown to have more intermixing of annuals and perennials than KS5 making boundaries between patches very difficult to determine in the field and producing a heterogeneous effect at the fine scale.

The results show that the autocorrelation approach is capable of describing the pattern at each of the sites as being much more heterogeneous than the CSIRO classification (constructed by drawing boundaries round landscape types) allows for. Given that in reality the landscapes exhibit continuous variation, modelling by autocorrelation appears to give a more accurate reflection of the truth.

This method breaks away from procedures that impose structure prior to analysis. This is important as currently available procedures are failing to describe landscapes adequately in northern Australia. The autocorrelation approach therefore has potential to be one possible way of dealing with these landscapes in the future (Pearson, 2000).