Effects of Applying Pig Manure on Immobilization Remediation of Cadmium Contaminated Soil with Clay Minerals

Xu Yi; Wang Yongxin; Qin Xu; Wang Lin; Xu Yingming

doi:10.14083/j.issn.1001-4942.2017.1.016

Abstract：A pot experiment was conducted to evaluate the effects of adding pig manure on immobilization remediation of cadmium contaminated soil with sepiolite and attapulgite.The results showed that adding pig manure under sepiolite remediation resulted in the decrease of Lactuca sativa L.biomass,but the attapulgite remediation coupled with high dose of pig manure (15 g/kg) could increase the Lactuca sativa L.biomass by 6.6％.Under clay mineral remediation,applying pig manure did not significantly change the nitrite content in Lactuca sativa L.except that the treatment of sepiolite (10 g/kg) + pig manure (15 g/kg) significantly decreased the nitrite content in Lactuca sativa L..The decrease of soil pH value was not obvious after adding pig manure under clay mineral remediation.Single applying pig manure had not obvious decreasing effect on soil available Cd but even activation effect,which resulted in the soil available Cd increased slightly.Under clay mineral remediation,applying pig manure could slightly decrease the soil available Cd content,but the difference was not significant.The Cd content in edible part of Lactuca sativa L.decreased by 7.1％ and 14.3％ respectively under sepiolite and attapulgite immobilization remediation.Only adding pig manure could reduce Cd content in Lactuca sativa L.by 10.7％～ 25.0％.Under sepiolite and attapulgite remediation,applying pig manure could induce Cd content in Lactuca sativa L.by 32.1％～35.7％ and 35.7％～39.3％ respectively.Under sepiolite remediation,adding pig manure could increase the soil available nitrogen,phosphorus and potassium content and nutrition level of plants,but the effect was not obvious.Attapulgite remediation had no significant effect on soil available nitrogen,but adding medium and high amount of pig manure could significantly increase the concentration of soil available phosphorus,and the concentration of soil available potassium could be obviously increased by adding low and medium amount of pig manure.