不同矿物调理剂对Cd污染水田土壤性质及水稻Cd含量的影响.

[Objective] The present paper aimed to investigate the effects of different mineral conditioners on the soil properties of cadmium (Cd)-contaminated paddy fields and the Cd content of rice in Guangxi, so as to provide a reference basis for the utilization of paddy fields to produce safe rice. (Method) Calcium-magnesium-silicon conditioners A and B, calcium-silicon conditioner C and calcium-magnesium conditioner D(set up as treatments A, B, C and D, respectively) were selected to carry out Cd-contaminated field remediation and treatment experiments in a Cd-contaminated paddy field in Guangxi, and no n-conditioner was applied as control (CK). The pH, cation exchange capacity (CEC), total Cd and soil available Cd content, Cd content of rice roots, stems, leaves and seeds were determined at the rice maturity stage after the treatment to analyze the remediation and treatment effects of different mineral conditioners on Cd-contaminated paddy soils and the residual status of Cd in various parts of rice, and to analyze the correlation between soil total Cd content, CEC and pH and available Cd content. [Result] The application of mineral conditioner could significantly increase soil pH and CEC of Cd-contaminated paddy fields (P<0.05, the same as below), both of which were increased by 15.0% 16.6% and 20.4% -23.8% respectively compared with those of CK; And it could significantly reduce the Cd content in the available state of soil in Cd-contaminated paddy fields, which was decreased by 14.0%-19. 3% compared with that of CK. The soil available state Cd content of the paddy field after the application of mineral conditioners showed a significantly negative correlation with pH, and the correlation coefficient between the log In(pH) value of pH and the soil available state Cd content was 0. 4053; It showed a highly significantly negative correlation with CEC(P<0.01), and the correlation coefficient was 0.6326; With the increase in soil pH and CEC, the soil available state Cd content continuously decreased. The applications of mineral conditioners were all available in reducing the Cd content of rice roots, stems, leaves and seeds as well as the enrichment factor of Cd in the aboveground part of rice, in which the total Cd content of rice seeds was decreased by 35.9% 50.2%, and the enrichment factor of Cd in the aboveground part of rice (stems, leaves and seeds) was decreased by 19.5% -33.5%,32.1%-44.9% and 38.6%-52.6%, respectively. [Conclusion] The application of different mineral conditioners can significantly increase the pH and CEC of paddy soils, thereby reducing the Cd content in the active state of the soil, inhibiting the migration of Cd from the soil to the roots, stems, leaves, and seeds of rice, decreasing the Cd content in rice, and reducing the enrichment of Cd in the aboveground parts of rice (stems, leaves and seeds). [ABSTRACT FROM AUTHOR]