Colonisation of rehabilitated lands by termites (Dictyoptera),\ud Rio Tinto Alcan Gove bauxite mine, Northern Territory, Australia

The pattern of termite colonisation and the production of termite constructs are reported from a 26-year age\ud series of sites rehabilitated after bauxite mining in northern tropical Australia. Initial colonisation probably\ud occurs at the time of profile reconstruction and termites were active within eight months of seeding in wood\ud decomposing on the surface and partially buried in the profile. Termite activity, as determined by consumption of paper baits, was observed at sites rehabilitated for three or more years after seeding and rapidly reached levels approaching that in adjacent unmined native forest ecosystems. Termites colonising rehabilitated sites are predominantly those that feed on decomposing wood or are\ud polyphagous; some litter-feeding species are transitorily present but disappear near the time of canopy closure. Common local species not observed so far in rehabilitated environments included Coptotermes acinaciformis and certain soil (humus)-feeding species. Termite galleries were almost ubiquitous in the developing upper A horizons of sites rehabilitated for eight or more years and had penetrated to 40–50 cm at sites rehabilitated for 16 years. Surface mounds of woodand litter-feeding species were apparent at sites rehabilitated for three or more years. Evidence of termite feeding was universal in dead plant materials although damage to living plants was minimal, sporadic and of little ecological consequence, except at one site rehabilitated after the deposition of red mud. Forest development and the changing availability of food materials had a critical role in enabling colonisation of the rehabilitated environments by key termite groups. Colonisation in turn interplayed with soil development because of the increasingly diverse termite activities occurring in the rehabilitated environments with time. This emphasises the important roles termites play in decomposition and soil formation processes