title: Towards understanding the stabilization process in vermicomposting using PARAFAC analysis of fluorescence spectra.
abstract: In this study, fluorescence excitation-emission matrix (EEM) combined with parallel factor analysis (PARAFAC) was employed to trace the behavior of water extractable organic matter and assess the stabilization process during vermicomposting of sewage sludge and cattle dung. Experiments using different mixing ratios of sewage sludge and cattle dung were conducted using Eisenia fetida. The results showed that vermicomposting reduced the DOC, DOC/DON ratio and ammonia, while increased the nitrate content. A three-component model containing two humic-like materials (components 1 and 2) and a protein-like material (component 3) was successfully developed using PARAFAC analysis. Moreover, the initial waste composition had a significant effect on the distribution of each component and the addition of cattle dung improved the stability of sewage sludge in vermicomposting. The PARAFAC results also indicated that protein-like materials were degraded and humic acid-like compounds were evolved during vermicomposting. Pearson correlation analysis showed that components 2 and 3 are more suitable to assess vermicompost maturity than component 1. In all, EEM-PARAFAC can be used to track organic transformation and assess biological stability during the vermicomposting process.
authors: Institute of Biofilm Technology (IBT), Key Laboratory of Yangtze River Water Environment, Ministry of Education, State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
authors: Baoyi
authors: B
authors: Lv
authors: Institute of Biofilm Technology (IBT), Key Laboratory of Yangtze River Water Environment, Ministry of Education, State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China. Electronic address: xingmeiyan@tongji.edu.cn.
authors: Meiyan
authors: M
authors: Xing
authors: Institute of Biofilm Technology (IBT), Key Laboratory of Yangtze River Water Environment, Ministry of Education, State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
authors: Chunhui
authors: C
authors: Zhao
authors: Institute of Biofilm Technology (IBT), Key Laboratory of Yangtze River Water Environment, Ministry of Education, State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
authors: Jian
authors: J
authors: Yang
authors: Institute of Biofilm Technology (IBT), Key Laboratory of Yangtze River Water Environment, Ministry of Education, State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
authors: Liang
authors: L
authors: Xiang
mesh_terms: D000818:Animals; D002417:Cattle; D004784:Environmental Monitoring / Q000379:methods*; D005163:Factor Analysis, Statistical; D005243:Feces / Q000737:chemistry*; D006812:Humic Substances / Q000032:analysis*; D009835:Oligochaeta / Q000378:metabolism*; D012722:Sewage / Q000737:chemistry*; D013050:Spectrometry, Fluorescence
chemical_list: D006812:Humic Substances; D012722:Sewage
keywords: Excitation–emission matrix (EEM); Parallel factor analysis (PARAFAC); Stabilization process; Vermicomposting; Water extractable organic matter (WEOM)