Effects of acidity on acute toxicity of aluminium-waste and aluminium-contaminated soil

Quantified the amount of Al, Cu, Zn, Mb, Pb, Ni and Cd extracted by distilled water and ammonium acetate at pH 3.8, 4.8, 5.8, 6.8 and 7.8. One bioassay, in terms of seed germination and root elongation of Brassica parachinensis, indicated that germination rates were seriously retarded by Al-waste even at neutral pH; <25% seeds were germinated in Al-waste and the toxic effect was more obvious at pH 3.8. Root growth in Al-waste and Al-soil was slower than in the control and no seedling in Al-waste had roots >2cm at the end of this study. The photosynthetic rate of Chlorella pyrenoidosa was significantly inhibited by Al-waste when compared with the control, although the pH effect was not clear. -from Authors