title: Influence of humic substances on bioavailability of Cu and Zn during sewage sludge composting.
abstract: Influence of humic substances (HS) on bioavailability of Cu and Zn was characterized during 120 days co-composting of sewage sludge and maize straw. At the initial stage of composting, Cu and Zn in sewage sludge were released as organic matter was degraded, and water soluble Cu and Zn increased markedly. Water soluble Cu and FA content decreased after 21 days whereas water soluble Zn increased during the whole process. Both HA-Cu and HA-Zn were significantly and positively correlated with HA and H/F, respectively. At the end of composting, the distribution coefficients of HA-Cu and HA-Zn reached 27.50% and 3.33% respectively with HA-Cu/HA-Zn ratio increased from 1.29 to 2.73. The results suggest that Cu combined with HA more strongly than Zn, and composting treatment could decrease bioavailability of Cu markedly.
authors: College of Resources and Environment, Northwest A&F University, Yangling, Shaanxi Province 712100, PR China.
authors: Jun
authors: J
authors: Kang
authors: Zengqiang
authors: Z
authors: Zhang
authors: Jim J
authors: JJ
authors: Wang
mesh_terms: D001682:Biological Availability; D003300:Copper / Q000493:pharmacokinetics*; D006812:Humic Substances; D012722:Sewage; D012987:Soil; D015032:Zinc / Q000493:pharmacokinetics*
chemical_list: D006812:Humic Substances; D012722:Sewage; D012987:Soil; D003300:Copper; D015032:Zinc