Restoring the Soils of Nauru: Plants as Tools for Ecological Recovery
The restoration of Nauru’s mined areas is fundamental to the future wellbeing of the people and ecosystems of Nauru. Extensive open cast phosphate mining on Nauru over the last 100 years has led to soil losses and landscape degradation to the extent that over 70% of this South-Western Pacific island state is now uninhabitable and almost all productive land has been lost. Significant landscape degradation has occurred and as a consequence the soils that remain are insufficient in volume and quality to achieve the Government’s restoration goals which support the long-term development of Nauru and the well-being of its people. The aim of this research is to evaluate aspects of cover-crop use as a means for soil restoration in Nauru. This research evaluates biomass production, phytoremediation potential, and germination success for a range of species in Nauruan soils. Field trials exploring biomass production and cadmium phytoextraction were performed, as was an experiment assessing the effects of cadmium on germination success. It was found that, in the circumstances assessed, biomass productivity was significantly determined by species, mulch use, soil type, and to a small degree – cadmium. Phytoextraction was significantly determined by tissue type. Germination success was not determined by soil cadmium, but soil type was a significant factor.