Ms Amber Bateman1, Dr Todd Erickson1, Dr Erik Veneklaas1, Dr David Merrit2, Dr Miriam Munoz-Rojas3
1The University Of Western Australia, Perth, Australia, 2The Department of Biodiversity,Conservation and Attractions, Perth, Australia, 3The University of New South Wales, Randwick, Australia
In the arid Pilbara region in the north-west of Western Australia the disturbance footprint caused by large-scale mining practices exceeds 230,000 ha and has contributed to the loss of soil quality and functional ecosystems. Soils used in mine site rehabilitation are physically, chemically and biologically different to natural topsoil and lack the soil nutrients, organic matter and biological life necessary to support plant life and sustainable ecosystems. As such, the rehabilitation of these landscapes is challenging. Here, we present case studies based on the Pilbara region that examines the effect of organic and inorganic soil amendments (gypsum, urea, mulches and biochar) on plant establishment and soil quality in the context of mine site rehabilitation in an arid landscape. In addition, we discuss the role of native plant communities to improve soil quality. This research sought to test the effectiveness of soil amendments to promote soil recovery and the recruitment of plants used in dryland rehabilitation. Our results showed that although the use of inorganic amendments increased plant growth, the effects on soil quality is limited. However, the use of mulches as an amendment in rehabilitation increased soil organic matter and soil microbial activity. The soil quality of mine soils increased through the successful establishment of a diverse native plant community that increased litter quality and quantity. However, water was the predominant driver for determining the effectiveness of the soil amendments with changes in soil and plant indicators significantly decreasing as water became scarce. These studies contribute to understanding how soil amendments effect soil quality and plant recruitment in post-mining rehabilitation in arid regions and their role in reinstating functioning ecosystems.
I am a third- year PhD student at the University of Western Australia and Kings Park Botanic Gardens in Perth. My project involves working with mining industry partners to develop methods for improving the soil quality of soil substrates used in mine site rehabilitation in the Pilbara. Through this research I hope to find ways of increase soil physical, chemical and biological health using a various organic and inorganic soil amendments and diverse native plant communities to encourage the establishment of sustainable native ecosystems on mine rehabilitation sites.