title: Microbial enzyme and biomass responses: Deciphering the effects of earthworms and seasonal variation on treating excess sludge.
abstract: This paper reports on a seasonal pattern comparison of microbial enzymatic activities and biomass responses based on a conventional biofilter (BF, without earthworm) and a vermiﬁlter (VF, with earthworm, Eisenia fetida) for excess sludge treatment. The volatile suspended solids (VSS) reduction, viable cell number and enzyme activities were assayed to probe what made the VF operate stably. The results indicated that the earthworm activities can polish the VSS reduction with 27.17% more than the BF. Though the VF had a lower level in the viable cell number compared with the BF, the earthworm strongly improved the microbial enzymatic activities such as INT-dehydrogenase, protease, β-glucosidase and amylase, which can explain the excellent performance of VSS reduction. The correlation analysis documented that the VSS reduction was positively correlated with microbial enzyme activities. More importantly, the earthworm enabled the VF to avoid the detrimental influence of temperature, which guaranteed a stable performance during seasonal variations.
authors: The Institute of Biofilm Technology, Key Laboratory of Yangtze River Water Environment, Ministry of Education, 1239 Siping Road, Shanghai, China; College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Urban Constitution Designed & Research Institute, Shanghai 200011, China.
authors: Xiaojie
authors: X
authors: Ma
authors: The Institute of Biofilm Technology, Key Laboratory of Yangtze River Water Environment, Ministry of Education, 1239 Siping Road, Shanghai, China; College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China. Electronic address: xingmeiyan@tongji.edu.cn.
authors: Meiyan
authors: M
authors: Xing
authors: The Institute of Biofilm Technology, Key Laboratory of Yangtze River Water Environment, Ministry of Education, 1239 Siping Road, Shanghai, China; College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
authors: Yin
authors: Y
authors: Wang
authors: The Institute of Biofilm Technology, Key Laboratory of Yangtze River Water Environment, Ministry of Education, 1239 Siping Road, Shanghai, China; College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
authors: Zhe
authors: Z
authors: Xu
authors: The Institute of Biofilm Technology, Key Laboratory of Yangtze River Water Environment, Ministry of Education, 1239 Siping Road, Shanghai, China; College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
authors: Jian
authors: J
authors: Yang
mesh_terms: D000818:Animals; D001419:Bacteria / Q000201:enzymology*; D018533:Biomass; D019149:Bioreactors; D005374:Filtration; D006801:Humans; D006868:Hydrolysis; D009835:Oligochaeta / Q000502:physiology*; D010088:Oxidoreductases / Q000737:chemistry; D012722:Sewage; D012988:Soil Microbiology; D013696:Temperature
chemical_list: D012722:Sewage; D010088:Oxidoreductases
keywords: Dehydrogenase activity; Excess sludge treatment; Hydrolyses activity; Temperature; Viable cell number