农业环境科学学报2025，Vol.44Issue(4)：919-929,11.DOI:10.11654/jaes.2024-0250
不同钝化剂对土壤镉有效性与生物可给性的对比影响研究
Comparison of effects of different amendments on availability and bioaccessibility of cadmium in soils
摘要
Abstract
A soil incubation experiment was conducted in this study to investigate the effects and mechanisms of three different passivating agents on the availability,chemical forms,and bioaccessibility of cadmium(Cd)in two distinct soils.Mercapto-palygorskite(MP),hydroxyapatite(HAP),and iron-modified biochar(FeBC)were used as passivating agents.Paddy soil(acid)collected from Xiangtan and fluvo-aquic soil(weakly alkaline)from Jiyuan were utilized as test soils.A combined experiment of in vitro digestion and sequential extraction as well as redundancy analysis(RD A)were employed to reveal the functional mechanisms of these agents on the bioaccessibility of Cd.The findings showed that MP and HAP treatments significantly reduced the available Cd concentrations in two soils,with maximal reduction rates of 82.27％and 47.88％,respectively,whereas the addition of FeBC significantly increased Cd availability.MP treatments significantly reduced the Cd bioaccessibility in the intestinal phase in Jiyuan and Xiangtan soils,with maximal reductions of 97.97％and 51.11％,respectively.HAP addition significantly decreased Cd bioaccessibility in the intestinal phase in Xiangtan soil,with a maximal reduction of 54.13％.Conversely,the addition of high-dose FeBC significantly increased Cd bioaccessibility in the gastric phase in both soils.Application of MP and HAP promoted the conversion of exchangeable Cd to Fe/Mn oxide-bound Cd in both soils,while FeBC treatments advanced the conversion of carbonate-bound Cd and Fe/Mn oxide-bound Cd to exchangeable Cd in two soils.The results of the combined experiment and RDA indicated that exchangeable Cd was the primary source of bioaccessible Cd in both soils,and the three amendments influenced Cd bioaccessibility mainly by affecting the dissolution of exchangeable Cd.MP is the most effective among the three amendments,and has promising application potential in reducing the health risks associated with soil Cd pollution.关键词
钝化修复/镉/有效性/生物可给性/化学形态Key words
immobilization remediation/cadmium/availability/bioaccessibility/chemical speciation分类
环境科学引用本文复制引用
许华强,王林,孙约兵,戴子纯,邓凯,王童玉,梁学峰..不同钝化剂对土壤镉有效性与生物可给性的对比影响研究[J].农业环境科学学报,2025,44(4):919-929,11.基金项目
国家自然科学基金项目(41571322) （41571322）
中国农业科学院科技创新工程项目(CAAS-CSGLCA-2020302)National Natural Science Foundation of China(41571322) （CAAS-CSGLCA-2020302）
Innovation Program of the Chinese Academy of Agricultural Sciences(CAAS-CSGLCA-2020302) （CAAS-CSGLCA-2020302）
