In order to evaluate the effect of flyash on chemical speciation, total content, DTP A extractable content of Cu and Zn, and potherb mustard seed germination during aerobic composting, a composting study was conducted in a pilot reactor. Swine manure was mixed with com stalk powder as a bulking agent, and the mixtures were amended with flyash at 0% , 2.5%, 5.0%, 7.5% and 10% (w/w) and composted for 90 days in the experiment. The results showed that total Cu and Zn concentration in compost piles increased during the composting process, while the percentages of DTP A extractable Zn and Cu in compost piles decreased and showed more significant in treatment with 5 % flyash . The Sposito' s chemical speciation analysis showed that the fractionation was in the order of Cu - NaOH > Cu -HNO3 > Cu - EDTA > Cu - Residue > Cu - KNO3 > Cu - H2O and Zn - HNO3 > Zn - EDTA > Zn - NaOH > Zn -rnResidue > Zn - KNO3 > Zn - H2O for Cu and Zn respectively. The Cu - KNO3, Cu - H20, Zn - KNO3 and Zn - H2O content decreased with the composting time prolong, while there was no significant difference among the treatments. The potherb mustard seed germination was strongly influced by the flyash adding, especially when the addition amount exceeded 5 % . The results implicated that the DTPA extractable Zn and Cu could be greatly decreased by adding flyash during the swine manure composting and the suitable addition would be 5 % of flyash, according to the potherb mustard seed germination test results.%以猪粪为堆肥原材料,以玉米秸秆粉为调理剂,并添加干质量比为0％、2.5％、5.0％、7.5％和10％的粉煤灰进行90d好氧堆肥,研究了不同用量粉煤灰对猪粪堆肥过程中Cu、Zn总量、有效态含量、化学形态和雪里蕻种子发芽的影响.结果表明:随着堆肥时间的延长,堆体Cu和Zn总量的浓度水平逐渐增加,但DTPA提取态Cu和Zn在其总量浓度水平中所占的比例则逐渐降低,且以添加5％粉煤灰最为明显.Sposito法形态分析显示,堆体中Cu的各种形态比例为Cu-NaOH＞ Cu-HNO3＞ Cu-EDTA＞ Cu-Residue＞ Cu-KNO3＞ Cu-H2O,Zn各种形态比例为Zn-HNO3＞ Zn-EDTA＞ Zn-NaOH＞ Zn-Residue＞ Zn-KNO3＞ Zn-H2O,随着堆肥时间的延长,Cu-KNO3、Cu-H2O、Zn-KNO3和Zn-H2O在总量中所占的比例则逐渐降低,但Cu和Zn的不同形态所占比例在不同处理之间差异不大.雪里蕻种子萌发指数表明,增加粉煤灰用量会对雪里蕻种子萌发产生抑制,尤其是当粉煤灰用量超过5％时更是如此.研究认为,虽然猪粪和粉煤灰好氧混堆可以降低Cu、Zn的生物有效性,但考虑到粉煤灰对雪里蕻种子萌发产生抑制,添加5％粉煤灰是较合适的添加比例.
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