TY - JOUR
T1 - Toxicity evaluation of weathered coal fly ash-amended manure compost
AU - Lau, S. S.S.
AU - Wong, J. W.C.
N1 - Funding Information:
This research was supported by a grant from the Rockefeller Brothers Fund. The authors would like to thank Mr. K. K. Ma for his excellent technical assistance.
PY - 2001
Y1 - 2001
N2 - The general use of manure compost is limited by its residual toxicity, and hence a study was performed to evaluate the use of weathered coal fly ash (lagoon ash) to alleviate the toxicity of manure compost. Mature and immature manure compost were amended with lagoon ash at 0, 5, 10 and 20% (w/w dry weight basis), and their phyto-toxicity was evaluated by germination and root length growth of lettuce seed. The immature manure compost had significantly higher contents of NH4-N, PO4-P, and acid- and water-extractable Cu and Zn contents than those of mature manure compost. Ash amendment caused a significant increase in electrical conductivity (EC), but a decrease in NH4-N, PO4-P, and DTPA-, CaCl2- and water-extractable Cd, Cu, Pb and Zn contents of both manure compost. Addition of lagoon ash at a rate of 5% for immature manure compost and 10% for mature manure compost resulted in a higher seed germination rate and root length growth. The germination index demonstrated significant negative correlations with EC, NH4-N and DTPA extractable Cd, Cu, Pb and Zn contents. The present study supports the use of lagoon ash for amending manure compost to reduce the availability of trace elements and NH4-N.
AB - The general use of manure compost is limited by its residual toxicity, and hence a study was performed to evaluate the use of weathered coal fly ash (lagoon ash) to alleviate the toxicity of manure compost. Mature and immature manure compost were amended with lagoon ash at 0, 5, 10 and 20% (w/w dry weight basis), and their phyto-toxicity was evaluated by germination and root length growth of lettuce seed. The immature manure compost had significantly higher contents of NH4-N, PO4-P, and acid- and water-extractable Cu and Zn contents than those of mature manure compost. Ash amendment caused a significant increase in electrical conductivity (EC), but a decrease in NH4-N, PO4-P, and DTPA-, CaCl2- and water-extractable Cd, Cu, Pb and Zn contents of both manure compost. Addition of lagoon ash at a rate of 5% for immature manure compost and 10% for mature manure compost resulted in a higher seed germination rate and root length growth. The germination index demonstrated significant negative correlations with EC, NH4-N and DTPA extractable Cd, Cu, Pb and Zn contents. The present study supports the use of lagoon ash for amending manure compost to reduce the availability of trace elements and NH4-N.
KW - Coal fly ash
KW - DTPA
KW - Germination index
KW - Heavy metals
KW - Manure compost
UR - http://www.scopus.com/inward/record.url?scp=0035038332&partnerID=8YFLogxK
U2 - 10.1023/A:1010332618627
DO - 10.1023/A:1010332618627
M3 - Journal article
AN - SCOPUS:0035038332
SN - 0049-6979
VL - 128
SP - 243
EP - 254
JO - Water, Air, and Soil Pollution
JF - Water, Air, and Soil Pollution
IS - 3-4
ER -