title: Speciation and transformation of heavy metals during vermicomposting of animal manure.
abstract: This work was conducted to evaluate the effects of vermicomposting on the speciation and mobility of heavy metals (Zn, Pb, Cr, and Cu) in cattle dung (CD) and pig manure (PM) using tessier sequential extraction method. Results showed that the pH, total organic carbon and C/N ratio were reduced, while the electric conductivity and humic acid increased after 90days vermicomposting. Moreover, the addition of earthworm could accelerate organic stabilization in vermicomposting. The total heavy metals in final vermicompost from CD and PM were higher than the initial values and the control without worms. Sequential extraction indicated that vermicomposting decreased the migration and availability of heavy metals, and the earthworm could reduce the mobile fraction, while increase the stable fraction of heavy metals. Furthermore, these results indicated that vermicomposting played a positive role in stabilizing heavy metals in the treatment of animal manure.
authors.affiliation: College of Ocean Science and Engineering, Shanghai Maritime University, Shanghai 201306, China; Institute of Biofilm Technology, Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
authors.forename: Baoyi
authors.initials: B
authors.lastname: Lv
authors.affiliation: Institute of Biofilm Technology, Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China. Electronic address: xingmeiyan@tongji.edu.cn.
authors.forename: Meiyan
authors.initials: M
authors.lastname: Xing
authors.affiliation: Institute of Biofilm Technology, Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Yang
mesh_terms: D000818:Animals; D001673:Biodegradation, Environmental; D002417:Cattle; D004553:Electric Conductivity; D006812:Humic Substances / Q000032:analysis; D008372:Manure; D019216:Metals, Heavy / Q000032:analysis / Q000737:chemistry*; D009835:Oligochaeta / Q000378:metabolism*; D012989:Soil Pollutants / Q000032:analysis / Q000737:chemistry*; D013552:Swine
chemical_list: D006812:Humic Substances; D008372:Manure; D019216:Metals, Heavy; D012989:Soil Pollutants
keywords: Animal manure; Heavy metal; Sequential extraction; Stabilization; Vermicomposting