Aspergillus Tubingensis Reduces the pH of the Bauxite Residue (Red Mud) Amended Soils
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Bauxite residue (red mud), a poor substrate for plant growth because of very high pH, salinity and sodicity, is required to be revegetated. The possibility of using Aspergillus tubingensis (AT1), a phosphate solubilizer in red mud amended soils to reduce the alkalinity of the red mud was studied in the present study. A. tubingensis was tested for its ability to grow at high pH and in different concentrations of aluminium (Al), iron (Fe) and sodium (Na). The results showed that A. tubingensis was able to grow at high pH and reduce the alkalinity of the nutrient medium and also to accumulate different metals in the mycelium. The pH values of the red mud amended soils were also significantly reduced (by 2–3 units) by A. tubingensis, which resulted in maize growth improvement. These results suggest that A. tubingensis plays an important role in reducing the pH of the red mud and also helps in promoting the plant growth in it.
KeywordsAspergillus tubingensis bauxite residue bioremediation red mud
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- Fuller, R. D. and Richardson, C. J.: 1986, ‘Aluminate toxicity as a factor controlling plant growth in bauxite residue’, Env. Tox. Chem. 5, 905–915.Google Scholar
- Hunt, N. and Gilkes, B.: 1992, Land Monitoring Handbook. University of Western Australia, Nedlands, Western Australia.Google Scholar
- McArthur, W.: 1991, References soils of south Western Australia, Western Australia's Department of Agriculture, Western Australia.Google Scholar
- Valarie, Ee.: 1999, Bioremediation of Bauxite Residue Using Indigenous Bacteria. Mineral Council of Australia Environmental Workshop, 311p.Google Scholar
- Wong, J. W. C. and Ho, G. E.: 1991, ‘Effects of gypsum and sewage sludge amendment on physical properties of fine bauxite refining residue’, Soil Sci. 152, 326–332.Google Scholar