Amendment of Minesite Acid Sulfate Soils and the Use of Vetiver Grass for Re-vegetation in Dabaoshan Mine,

Abstract: We report the preliminary results from our vetiver grass growth experiments, part of a minesite rehabilitation research project in Guangdong Dabaoshan Mine. The investigated acid sulfate soil was extremely acidic with pH as low as 2.76. Pot trials were conducted to investigate the effects of various soil treatments on the growth of a vetiver grass (Vetiveria zizanioides). These treatments involve the uses of quick- and slow-reacting acid-neutralizing agents- hydrated lime and red mud (bauxite refinery residues), biosolids, fertilizer and zeolite. The results show that treatment of the soil with “red mud ” and hydrated lime enables the establishment of vetiver grass by correcting soil acidity and eliminating metal toxicity. Over-liming affected the growth of vetiver grass but some seedlings have survived the alkaline conditions. Over-application of zeolite powder might cause detrimental effects on vetiver grass, however, further examination is needed to provide proofs. The application of chemical fertilizer additional to the above mentioned soil conditioners had worse effects on the growth of the vetiver grass