Abstract:Ion-adsorption type rare earth ore is rich in valuable strategic resources of mid-heavy rare earths, and ammonia nitrogen pollution caused by its industrial mining process has long attracted attention. Column leaching using magnesium sulfate, calcium chloride and ammonium sulfate were employed to prepare simulated ion-adsorption rare earth tailings, and Zhonghuang 13 soybean was used as experimental crop. Outdoor pot experiments were conducted to explore ecological impact on the soil in ion-adsorption rare earth mining area. The results show that compared to soybean planted in ammonium-leached tailings, the soybeans planted in magnesium-leached or calcium-leached tailings grow quite or higher in plant height, chlorophyll content of their leaves is higher or equivalent, and their root system grows normally with obvious axial root and vigorous lateral roots. This may be attributed to the fact that magnesium and calcium can directly involve in synthesis of chlorophyll, accelerate transportation of sugar, and improve soil hardness. Leaching of ion-adsorption type rare earth ore using magnesium sulfate and calcium chloride has less ecological impact on the soil in mining area compared to that using ammonium sulfate. The development direction of green mining and pollution prevention for ion-adsorption rare earth mining area were pointed out.