In order to evaluate the effects and mechanisms of flooding measures, soil conditioner, silicon mineral fertilizer and sprayed foliar fertilizer, gypsum powder, and their multiple treatments for reducing Cd accumulation in rice grown in Cd-contaminated soil. A plot experiment was conducted in three different Cd-contaminated soils. The results showed that flooding measures, a single application of conditioning agents, and combined application and flooding treatment can reduce soil-available Cd and the Cd content in various organs of rice with 6.58%-30.01% reduction in soil available-Cd and 12.64%-68.68% reduction in Cd content in brown rice, respectively. The Cd reduction decreased in the following order:comprehensive treatment (T6) > basic application of gypsum powder (T5) > base Xiangrunbang state soil conditioner (T3) > mineral silicon fertilizer and spray foliar fertilizer (T4) > flood treatment (T2). In addition, the average value of the reduction effect of the Cd content in brown rice was calculated. The five treatments in the experiment reduced the enrichment of various parts of the rice, which is a main reason for the decrease in Cd content in the brown rice. According to the field plot test, the combined application of the basic conditioning agent, mineral silicon fertilizer, and sprayed foliar fertilizer, and gypsum powder and flooding measures can be used as an effective method for Cd pollution control in Cd-contaminated cultivated rice.
Keywords: cadmium; enrichment coefficient; rice; silicon fertilizer; soil conditioner.