Abstract: In order to reduce the damage of heavy metals to soil, the tolerance and the enrichment effect of heavy metal Hg²+ on Elymus sibiricus and Poa crymophila under different mass concentrations were studied. In this study, pot experiments were conducted at room temperature, different concentrations of Hg²+ (HgCl₂, 0, 25, 50, 75 and 100 mg/L) and Hoagland aqueous solution were used to treat plant. The results showed that under different concentrations of heavy metal stress, Poa crymophila showed strong tolerance ability, while Elymus sibiricus showed weak tolerance. In addition, the enrichment ability of heavy metals in Poa crymophila was significantly higher than that in Elymus sibiricus, and the enrichment ability of heavy metals in intercropping Poa crymophila was higher than that in monoculture Poa crymophila. There was no significant difference in enrichment ability between monoculture Poa crymophila and intercropping Elymus sibiricus, but they all showed different degrees of enrichment ability. On the whole, Poa crymophila can be used as a preferred plant for remediation of heavy metal contaminated soil, especially intercropping Poa crymophila has the most significant enrichment effect on heavy metals, and can also improve the soil ecological environment.

Key words: heavy metal enrichment;Poa crymophila;Elymus sibiricus, tolerance, monocropping and intercropping