In an incubation study, impacts of applying different organic materials (pig manure, chick manure, peat and active carbon) , lime and combined uses of these materials on dynamical changes in soil pH and available Cd contents were investigated in order to offer applicable techniques to effectively reduce Cd availability in the td-polluted soil. The results showed that soil pH and available Cd contents were significantly affected by the treatments in the study. Soil pH was increased with an increase in rates of pig manure or lime, but decreased with incubation time till end of the incubation period (60 d). Lime + organic materials affected soil pH relatively more in the first 15 d than thereafter. Soil available Cd contents were negatively related to soil pH changes caused by different treatments and rates of pig manure and/or lime, that was, the higher the rate of pig manure or lime, the lower the soil available Cd contents. Compared with CK, the application of peat and active carbon also significantly reduced soil available Cd. Combined use of pig manure and lime reduced Cd availability far more than that of another one. All the treatments reduced soil available Cd as the incubation proceeded, particularly for the highest rate of lime, and followed by the highest rate of pig manure and active carbon. After 60 d incubation, soil available Cd contents of these three treatments reduced from 0.063, 0. 112 and 0. 105 to 0.044, 0.061 and 0.075 mg/kg, respectively.%本文采用土壤培养实验,探讨了不同有机物料(猪粪、鸡粪、泥炭和活性炭)、石灰及其有机物料与石灰配合施用对镉(Cd)污染土壤的pH和Cd有效性的影响,旨在为土壤Cd污染治理提供有效的方法和技术.结果表明:不同处理对土壤pH和Cd的有效影响显著.土壤pH随猪粪或石灰用量增加而增加,随培养时间而逐渐降低,60 d后趋于稳定；石灰+有机物料在0～5 d对土壤pH的影响较大,15 d后趋于稳定.土壤有效Cd含量与不同处理引起的土壤pH变化呈负相关,也与猪粪或石灰用量呈显著负相关,即二者用量越高,对土壤Cd有效性效的抑制效果越好.与对照相比,活性炭和泥炭处理能显著降低土壤Cd的有效性.石灰与猪粪配施比单施石灰对降低土壤有效Cd的效果更优.所有处理的土壤有效Cd含量都随时间的增加而降低,特别是高量石灰处理,其次为高量猪粪和高量活性炭处理.培养60 d后,这3个处理的土壤有效Cd含量分别从0 d时的0.063、0.112和0.105mg/kg降至0.044、0.061和0.075 mg/kg.
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