Remediation effect of cadmium contaminated soil by the combination of Lactobacillus plantarum and red mud

Bioaugmentation has been receiving much attention recently as an in-situ technology for the remediation of heavy metal polluted soils. To study the effects of the application of different dosages of Lactobacillus plantarum, red mud, and their mixture on cadmium-contaminated soil, the pot experiment was conducted to study the content of cadmium in garlic bolt, plant biomass, soil available Cd concentration, and soil physico-chemical property response. The results showed that: compared with the control, the application of Lactobacillus plantarum resulted in increase of available nitrogen, phosphorus and potassium in soils, while the addition of red mud only increased the content of soil available potassium. However, the biomass of garlic bolt was promoted by the application of Lactobacillus plantarum, red mud and their mixtures to different extend. Lactobacillus plantarum and red mud were applied alone or in combination could effectively reduce the contents of available Cd in the soil and Cd contents in plants, which was32.4%∼ 59.4% and 17.0%∼ 44.3% lower as compared to the control, respectively, the combination of Lactobacillus plantarum and red mud with high dose could obtain best effect on the solidification of cadmium.