Representation of ecological trends in remotely sensed data: Relating the probability of class membership to canopy composition and a vegetation ordination

Continuous phenomena such as semi‐natural heathland vegetation cannot be adequately represented by conventional image classification routines. Measures of the probability of class membership derived as a by‐product of the widely used maximum likelihood classification were, however, found to be significantly correlated to heathland composition. Furthermore, ecological trends in the vegetation ground data revealed by an ordination were associated with systematic variations in the probabilities of class membership. Mapping the probabilities of class membership will therefore model the continuous character of such vegetation more appropriately than the class ificationfrom which the probabilities were dervied.