畜禽粪便堆肥溶解态有机质三维荧光光谱特征及Cu络合

畜禽粪便中溶解态有机质（DOM）易与Cu发生络合，从而促进其向土壤溶液和地表水体中迁移。该文对比分析堆肥前后猪粪和牛粪DOM三维荧光光谱特征变化，并通过荧光猝灭滴定法研究了堆肥对猪粪和牛粪中DOM与Cu络合的影响。研究发现，未经堆腐的猪粪和牛粪DOM中均存在较强的类蛋白荧光峰，包括类酪氨酸峰和类色氨酸峰；除了类蛋白峰，牛粪DOM中还出现了类腐殖质荧光峰。经过堆肥后，猪粪DOM中类酪氨酸峰和类色氨酸峰强度显著减弱，并在可见光激发区域出现类腐殖质峰；与猪粪堆肥类似，牛粪堆肥后类酪氨酸峰和类色氨酸峰也隐没不现，在紫外激发区域出现类腐殖质峰，同时可见光激发区的类腐殖质峰荧光强度减弱，位置发生红移。荧光猝灭试验结果显示，猪粪和牛粪堆肥后与Cu络合容量显著降低。因此，堆肥后改变了畜禽粪便DOM组成，生成大量胡敏酸和富里酸物质，从而降低畜禽粪便中DOM-Cu络合物的迁移性和生物可利用性。

Change of three-dimentional excitation emission matrix fluorescence spectroscopic characterization of manure dissolved organic matter after composting and influence on its complexation with Cu

Dissolved organic matter (DOM) in animal manure may complex with Cu and facilitate its transmission to the soil solution and groundwater. The aim was to investigate the spectroscopic characterization of DOM isolated from pig, cattle manure and their composts using 3DEEM technology (the three-dimentional excitation emission matrix fluorescence), and to reveal the influence of composting process on DOM complexation with Cu by fluorescence quenching titration. The results showed that protein-like fluorescence peaks, including tyrosine-like and tryptophan-like peaks, were present in all DOM of pig and cattle manure. In addition to protein-like fluorescence peaks, humic-like fluorescence peak was also observed in cattle manure DOM. The fluorescence of tyrosine-like and tryptophan-like peak in DOM extracted from pig manure declined significantly after composting, at the same time, the humic-like fluorescence peak was observed in the compost although it did not exist in fresh pig manure. Similar to the pig manure, tyrosine-like and tryptophan-like peaks of cattle manure were not distinguishable after composting, meanwhile, the intensity of humic-like fluorescence peak stimulated by UV excitation had significantly increased. Moreover, subtle decrease in fluorescence of humic-like peak stimulated by visible excitation and a red shift of peak position were observed in comparison with the fresh cattle manure. Fluorescence quenching experiment indicated that the manure composts were characterized by the smaller binding capacities compared to the fresh manure. It was suggested that composting process may change compositions of manure DOM, with an elevated concentration of humic acid and fulvic acid, therefore may decrease the mobility and availability of DOM-Cu in animal manure.