College of Environment Science and Engineering, Central South University of Forestry and Technology, Changsha, 410004, China.
Environ Sci Pollut Res Int. 2018 Mar;25(9):8608-8619. doi: 10.1007/s11356-017-0921-2. Epub 2018 Jan 9.
A pot experiment was carried out to investigate the remediation of paddy soils contaminated with both Cd and As. The effects of a soil additive (HZB: hydroxyapatite + zeolite + biochar) on the chemical speciation of Cd and As in the soil and on the accumulation and translocation of these two elements in rice plants were studied. The application of HZB decreased the concentration of acid-extractable Cd in the soil by 7.3-32.6% by promoting the transformation of soil Cd from soluble to insoluble species; as a result, the concentration of organically bound Cd in the soil increased by 6.8-49.5%. The application of HZB also promoted the transformation of soil As from soluble to insoluble species, thus increasing the concentration of Ca-bound As by 34.1-93.4% and reducing the concentration of soil-exchangeable As by 12.2-55.1%. However, when the application rate of HZB was greater than 4.0 g kg, the concentration of soil-exchangeable As increased again. It was found that the application of HZB decreased the Cd and As bioaccumulation capacity of rice root, and among various rice organs, rice husk was the highest in Cd transferring capacity, whereas rice root was the highest in As transferring capacity. When the amount of HZB applied was 0.05-0.2%, the Cd and As concentrations in the various parts of the rice plants decreased significantly.
采用盆栽试验研究了土壤添加剂（HZB：羟基磷灰石+沸石+生物炭）对 Cd 和 As 复合污染稻田土壤中 Cd 和 As 化学形态及在水稻植株体内积累和迁移的影响。HZB 的施用可促进土壤 Cd 从可溶态向难溶态转化，使土壤中酸提取态 Cd 浓度降低 7.3%-32.6%，有机结合态 Cd 浓度增加 6.8%-49.5%。HZB 的施用也可促进土壤 As 从可溶态向难溶态转化，使土壤中 Ca 结合态 As 浓度增加 34.1%-93.4%，土壤交换态 As 浓度降低 12.2%-55.1%。但当 HZB 施用量大于 4.0 g kg-1时，土壤交换态 As 浓度又有所增加。HZB 的施用降低了水稻根的 Cd 和 As 生物积累能力，在各水稻器官中，稻壳的 Cd 迁移能力最强，而稻根的 As 迁移能力最强。当 HZB 用量为 0.05%-0.2%时，水稻植株各部位的 Cd 和 As 浓度均显著降低。
