不同镉污染特征稻田施用土壤调理剂修复效果

摘要

A field experiment of remediation effect of "Yufeng" passivator in different Cd pollution characteristics paddy soils in Chang-Zhu-Tan area. The results suggested that both soil conditioner and lime significantly increased the pH and decreased the content of available Cd in soil , absorption and accumulation of Cd in rice. Treatment with1500 kg/hm2 lime increased soil pH by 0.35 and thus decreased Cd content in rice by 34.54％, while the soil conditioner increased soil pH 0.30 and decreased Cd in rice grain up to 46.20％. the results also suggested the effect of lime on reducing Cd content in rice was regulated by available Cd in soil. However, the soil conditioner inhibited Cd absorption and translocation via several pathways. The results demonstrated the potential effect of "Yufeng" soil conditioner in reducing Cd concentration in rice grain, which was stable and ideal for wider application.%选择长株潭地区不同镉(Cd)污染特征稻田,施用"宇丰"土壤调理剂,探明其在不同Cd污染稻田中的修复效果.结果表明:施用的石灰和土壤调理剂皆可显著提高酸性土壤pH值,有效降低土壤有效态Cd含量,显著降低水稻对Cd的吸收积累.施用石灰1500 kg/hm2平均可提高土壤pH值0.35个单位,降低稻米Cd含量34.54％;而施用土壤调理剂1500 kg/hm2则可平均提高土壤pH值0.30个单位,降低稻米Cd含量46.20％,效果优于石灰.施用石灰降低稻米Cd含量的效果主要受土壤Cd有效率的调控;而施用土壤调理剂降低稻米Cd含量是多途径抑制水稻对Cd吸收和转运的综合效果,因而"宇丰"土壤调理剂降低稻米Cd含量的效果更稳定,适应范围更广.