Abstract
Organic fertilizer derived from animal manure can significantly improve soil fertility. However, limited research has investigated the capacity of exogenous organic fertilizer dissolved organic matter (DOM) to migration and transform heavy metals. In this study, the effect of chicken manure organic fertilizers with different maturity and their DOM on changes of Pb bioactivity was evaluated and the role of soil environmental factors driving the changes was determined through soil incubation, adsorption and leaching experiments. The FTIR results indicated that DOM derived from farmhouse chicken manure organic fertilizer (FCMD) contained more protein-like compounds and low maturity, while DOM from commercial chicken manure organic fertilizer (CCMD) contained more humic/fulvic acid and high maturity. FCMD and CCMD reduced the content of RES-Pb by 16.3–27.52 % and 6.66–13.98 %, respectively. And the effects of organic fertilizers and their DOM on Pb migration and activation follow the order of FCMD> CCMD> CK> commercial chicken manure organic fertilizer (CCM)> farmhouse chicken manure organic fertilizer (FCM). FTIR analysis showed that FCMD was primarily composed of aromatic unsaturated functional groups, and its adsorption capacity for Pb2+ was significantly lower than that of FCM. In addition, the application of FCMD significantly altered the physicochemical properties of soil and promoted the migration and leaching of Pb. FCMD not only causes the soil Pb2+ to be released into the effluent but also activates Pb from the stable form into the active form. In summary, animal manure with lower maturity has a risk to activate heavy metals and should be applied with cautions.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have