Objective  Passivator were applied on cadmium-contaminated yellow-brown dryland soil to determine the antipollution efficiency.

  Method  In an indoor culture experiment, a typical Cd-contaminated soil collected from a strictly controlled yellow-brown dryland in Guizhou was treated with cow manure (NF), corn biochar (SWT), lime (SH), apatite (LHS), bentonite (PRT), calcite (FJS), sepiolite (HPS), Bacillus megaterium (JDYB), or B. glialis (JZYB) as the deactivation agents. After 70 d of the treatments, the soils were tested for pH, organic matters, alkaline hydrolysable nitrogen, effective variation characteristics of phosphorus and available potassium, as well as total and available Cd.

  Result  (1) The various agents raised the soil pH by 0.03–0.88 with the greatest 14.94% increase induced by SH. And all of them, aside from SH, PRT, FJS, and HPS, significantly raised the organic matter content with the greatest increase of 31% over control by NF. NF also exerted the most increases on the available nutrients, such as 25.16% on alkaline-hydrolysable nitrogen , 31.89% on available phosphorus and 65.11% on available potassium. (2) FJS escalated the Cd in soil, but all other deactivation agents reduced the content by 0.1–0.26 mg·kg⁻¹, with LHS and HPS rendering the largest reduction. (3) Compared to the control, SH reduced the available Cd most by 30.56%. The efficacies of the tested agents ranked SH (36%)＞LHS (35%)＞SWT (28%)＞NF (26%)＞FJS (23%)＞PRT (22%)＞JDYB (20%)＞HPS (18%)＞JZYB (14%).

  Conclusion   Among the deactivation agents studied, NF exhibited the greatest improvement on the nutrient indices of the yellow-brown dryland soil and SH on Cd mitigation.