为探究不同钝化剂对Cd污染农田土壤的钝化修复效果，以轻度Cd污染农田土

In order to explore the passivation and remediation effect of different passivating agents on Cd-contaminated farmland soil, two mild-Cd-contaminated farmland soils were selected as research objects, two rice varieties with different Cd accumulation capacity were selected, and control (CK), lime (S) and Foam (H), lime + sepiolite (SH), lime + sodium metasilicate + magnesium sulfate heptahydrate (SNM), lime + humic acid (SF), straw biochar (W) and foliar spray Eight treatments of 0.2% chelated iron fertilizer (T) were used for in-situ passivation field trials to explore the effects of applying different passivation agents on the basic physical and chemical properties of soil and Cd morphology. The results show that, compared with the control, the passivator treatment has no significant effect on soil pH, CEC, and nutrient content. Among them, SF treatment can increase the content of available phosphorus and available potassium, and W treatment can increase the content of alkali-decomposed nitrogen and available potassium. S treatment, H treatment, and SH treatment will reduce soil fertility; each passivation treatment will increase the total amount of soil Cd, reduce the proportion of acid-soluble Cd, and promote heavy metal Cd to a more stable reducible and oxidizable state And residue state transformation, thereby reducing its mobility and bioavailability, of which SH treatment has the best passivation effect and T treatment has the worst. Therefore, it is recommended to combine the application of lime and sepiolite to repair mild Cd contaminated soil, and the application of organic fertilizer at the same time, in order to have a better passivation stabilization effect and soil fertilizer supply capacity

In order to explore the effect of different passivation agents on the passivation repair effect of Cd-contaminated farmland soil, 2 different Cd-accumulative rice varieties were selected, and control (CK), lime (S), sea foam (H), lime and sea foam (SH), lime were selected. Sodium sodium silicate, magnesium sulfate sulfate (SNM), lime and humus (SF), straw biochar (W) and leaf spray 0.2% chelated iron fertilizer (T) were tested in the field in situ passivation field, To explore the effects of applying different passivators on the basic physical and chemical properties of soil and cd morphology. The results showed that the passivation agent treatment had no significant effect on soil pH, CEC and nutrient content compared with the control, in which SF treatment could improve the content of effective phosphorus and quick-acting potassium, The W treatment could improve the content of alkali nitride and quick-acting potassium, and s treatment could be improved. H treatment, SH treatment will reduce soil fertility, each passivation treatment will increase the full amount of soil Cd, reduce the proportion of acid-soluble Cd, promote the heavy metal Cd to a more stable reduced state, oxidation state and residual state transformation, thereby reducing its transportability and biological effectiveness, Among them, SH treatment passivation effect is the best, T treatment is the worst. Therefore, it is recommended that lime and sea foam are used to repair mild Cd-contaminated soil, and organic fertilizer is applied at the same time, so as to have better passivation and stability and soil fertility capacity.

In order to explore the effect of different passivators on the remediation of Cd Contaminated Farmland Soil, two rice varieties with different Cd accumulation capacity were selected, including CK, s, h, SH, SNM, SF, W and so on Eight treatments of 0.2% chelated iron fertilizer (T) were sprayed on the leaves to carry out field experiments of in-situ passivation. The results showed that compared with the control, the passivator treatment had no significant effect on the pH value, CEC and nutrient content of the soil, in which SF treatment could increase the content of available phosphorus and available potassium, w treatment could increase the content of alkali hydrolyzed nitrogen and available potassium, while s treatment, h treatment and sh treatment could reduce the fertility of the soil; each passivation treatment could increase the total content of Cd in the soil, reduce the proportion of acid soluble CD, and promote the heavy metal CD The results show that sh treatment has the best passivation effect and t treatment has the worst. Therefore, it is recommended that lime and sepiolite should be combined to repair the soil with mild Cd pollution, and organic fertilizer should be applied at the same time, so as to have better passivation and stability effect and soil fertility<br>