Is 37 years sufficient for full return on the ant biota following restoration?

Abstract

To provide an assessment of ecosystem recovery in 1975-bauxite mined areas, the ant fauna of one area to be planted with Corymbia calophylla, one to be seeded with mixed native species, one to be topsoiled but unrehabilitated, and a forest control was sampled monthly, and latterly annually, between 197 6 and 1989.1n this 'long-term' study, it was concluded that although composition of the ant fauna had converged on that of the forest over the 14-year period, differences still persist. A companion 'short-term' study was performed in 1979 in 30 bauxite mines of different ages and rehabilitated by a range of different methods, plus three forest controls. As with the long-term study, the rate of fauna return, and the type of ants present, varied with the methods of rehabilitation used and no plots had converged on the forest in terms of the ants present. In order to examine the assertion that the observed differences between rehabilitated areas and forest controls will lessen with time, both sampling programs have been repeated in 20 12, using identical sampling methods, although only four of the rehabilitated areas from the short-term study were resampled. This presentation compares the current fauna with that observed in the original surveys to see whether differences in outcomes between the different rehabilitation prescriptions persist and whether the passage of considerable periods of time is an effective means of ensuring that fauna recovery does take place.