TY - JOUR
T1 - Evaluation of major constraints to revegetation of lead/zinc mine tailings using bioassay techniques
AU - Ye, Z. H.
AU - Shu, W. S.
AU - Zhang, Z. Q.
AU - Lan, C. Y.
AU - Wong, Ming Hung
N1 - Funding Information:
The authors would like to thank the Lechang Lead/Zinc Mine Company for supplying tailings materials and Professor A. D. Bradshaw of the School of Biological Sciences, University of Livepool, for his invaluable comments. Financial support from the Research Grant Council of University Grants Committee, Hong Kong (HKBC117/94M) and Chinese Natural Science Fund (no. 39770154) is gratefully acknowledged.
PY - 2002/6
Y1 - 2002/6
N2 - The residues from the extraction of lead/zinc (Pb/Zn) ores of most Pb/Zn mines are permanently stored in tailings ponds, which require revegetation to reduce their environmental impact. This can only be done if the main constraints on plant establishment are evaluated. This can readily be done by field and greenhouse studies. To test this, the properties of different tailings from Lechang Pb/Zn mine located at the north of Guangdong Province in southern China have been studied. Physical and chemical properties including concentrations of metals (Pb, Zn, Cd and Cu) in the tailings and soils collected from different sites have been measured. The results showed that tailings contain low nitrogen (0.016-0.075%), low-organic matter (0.58-1.78%), high salt (3.55-13.85 dS/m), and high total and diethylene-tetramine-pentaacetic acid (DTPA)-extractable metal concentrations (total: 1019-1642 μg g-1 Pb, 3078-6773 μg g-1 Zn, 8-23 μg g-1 Cd, and 85-192 μg g-1 Cu; DTPA-extractable: 59-178 μg g-1 Pb, 21-200 μg g-1 Zn, 0.30-1.5 μg g-1 Cd, and 4.3-12 μg g-1 Cu). Aqueous extracts of tailings/soils (10%, 20% and 30%, w/v) from different sites were prepared for testing their effects on seed germination and root elongation of a vegetable crop Brassica chinensis and a grass species Cynodon dactylon. It was found that root elongation provided a better evaluation of toxicity than seed germination. The ranking of toxicity using root elongation was: high-sulfur tailings > tailing dam > sparsely vegetated tailings > densely vegetated tailings > mountain soil for both plants. This order was consistent with DTPA-extractable Pb contents in the tailings and soils. B. chinensis seedlings were then grown in the mixtures of different proportions of tailings and farm soil for 4 weeks, and the results (dry weights of seedlings) were in line with the root elongation test. All these demonstrated that heavy metal toxicity, especially available Pb, low content of nutrient, and poor physical structure were major constraints on plant establishment and colonization on the Pb/Zn mine tailings.
AB - The residues from the extraction of lead/zinc (Pb/Zn) ores of most Pb/Zn mines are permanently stored in tailings ponds, which require revegetation to reduce their environmental impact. This can only be done if the main constraints on plant establishment are evaluated. This can readily be done by field and greenhouse studies. To test this, the properties of different tailings from Lechang Pb/Zn mine located at the north of Guangdong Province in southern China have been studied. Physical and chemical properties including concentrations of metals (Pb, Zn, Cd and Cu) in the tailings and soils collected from different sites have been measured. The results showed that tailings contain low nitrogen (0.016-0.075%), low-organic matter (0.58-1.78%), high salt (3.55-13.85 dS/m), and high total and diethylene-tetramine-pentaacetic acid (DTPA)-extractable metal concentrations (total: 1019-1642 μg g-1 Pb, 3078-6773 μg g-1 Zn, 8-23 μg g-1 Cd, and 85-192 μg g-1 Cu; DTPA-extractable: 59-178 μg g-1 Pb, 21-200 μg g-1 Zn, 0.30-1.5 μg g-1 Cd, and 4.3-12 μg g-1 Cu). Aqueous extracts of tailings/soils (10%, 20% and 30%, w/v) from different sites were prepared for testing their effects on seed germination and root elongation of a vegetable crop Brassica chinensis and a grass species Cynodon dactylon. It was found that root elongation provided a better evaluation of toxicity than seed germination. The ranking of toxicity using root elongation was: high-sulfur tailings > tailing dam > sparsely vegetated tailings > densely vegetated tailings > mountain soil for both plants. This order was consistent with DTPA-extractable Pb contents in the tailings and soils. B. chinensis seedlings were then grown in the mixtures of different proportions of tailings and farm soil for 4 weeks, and the results (dry weights of seedlings) were in line with the root elongation test. All these demonstrated that heavy metal toxicity, especially available Pb, low content of nutrient, and poor physical structure were major constraints on plant establishment and colonization on the Pb/Zn mine tailings.
KW - Brassica chinensis
KW - Cynodon dactylon
KW - Pb/Zn mine
KW - Root elongation
KW - Toxicity
KW - Yield
UR - http://www.scopus.com/inward/record.url?scp=0035986256&partnerID=8YFLogxK
U2 - 10.1016/S0045-6535(02)00054-1
DO - 10.1016/S0045-6535(02)00054-1
M3 - Journal article
C2 - 12137044
AN - SCOPUS:0035986256
SN - 0045-6535
VL - 47
SP - 1103
EP - 1111
JO - Chemosphere
JF - Chemosphere
IS - 10
ER -