重金属锌对猪粪堆肥过程中氧化还原类酶活性的影响

以猪粪和秸秆为主要试验材料,添加不同浓度重金属Zn,采取发酵罐处理方法,在好氧高温条件下研究了重金属Zn对猪粪堆肥过程中多酚氧化酶、脱氢酶活性的变化,以及堆腐过程堆体温度、堆料pH值、胡敏酸E4/E6值的变化。结果表明：（1）低量重金属Zn处理（L）较不添加重金属Zn（CK）和添加高量重金属Zn（H）堆料升温快、温度高、高温持续时间长。（2）重金属Zn的加入对堆料的pH值影响不大,不是影响堆肥进程的直接原因。（3）H处理在整个堆肥过程中E4/E6值均高于L和CK,表明高浓度Zn处理抑制腐殖质的缩合和芳构化。（4）L处理的多酚氧化酶活性大多数时间高于H处理的活性,说明低量重金属Zn更好地促进了木质素的降解及其产物的转化。（5）从整个堆肥过程来看,3个不同处理的脱氢酶活性表现出一定的不稳定性,可能是重金属对脱氢酶活性有抑制作用的同时发生＂抗性酶活性＂现象。

Effects of Heavy Metals Zn on Oxidoreductase Activity During Co-composting of Pig Manure and Straw

The changes of polyphenoloxidase and dehydrogenase activities,and the changes of composting temperatures,pH and humic acid E4/E6 of composting materials during aerobic fermentation in thermophilic aerobic state were studied in this paper.Pig manure and straw were used as the main experimental materials.There were three treatments in this experiment,one was with adding low content heavy metals Zn（L）,one was with adding high content heavy metals Zn（H）,another one was without adding exogenous heavy metals Zn（CK）.The results showed that：（1）The temperature of the treatment L increased more quickly compared with CK and H,with higher temperature and longer high temperature duration.（2）Heavy metals Zn had little effect on the pH of stacking,it was not the direct cause of composting process.（3）The E4/E6 value of the treatment H was higher than treatment L and CK,which indicated that adding high content heavy metals Zn inhibited condensation and aromatization of humus.（4）The polyphenoloxidase activity of treatment L were higher than the H,which indicated that low content of heavy metals Zn facilitated the decomposition of lignin and conversion of products.（5）Dehydrogenase activities of the three different treatments exhibited certain instability in the whole composting process,maybe heavy metals Zn had inhibitory effect on dehydrogenase activity meanwhile occurred resistive enzyme activity phenomenon.