Over-exploitation of rare-earth elements causes cadmium (Cd)- and lead (Pb)-contamination of rare-earth mine tailings. Here, Paspalum conjugatum was used as a hyperaccumulating perennial herb to evaluate its phytoextraction potential for removing metals in a hydroponic experiment. Further, an in-situ experiment was conducted for two years (2016–2018) to investigate the potential of P. conjugatum for reducing soil metal concentrations and to assess microbiome recovery on abandoned rare-earth mining land. Pinus massoniana was used for control treatments. We found that P. conjugatum produced metal transfer coefficients of 0.85 and 0.89 for Cd and Pb, respectively. The concentrations of Cd and Pb accumulated in P. conjugatum were 98.33 mg kg⁻¹ and 137 mg kg⁻¹, respectively. Using P. conjugatum, soil Pb and Cd concentrations were significantly decreased, and Cd concentrations approached acceptable levels (0.209 mg kg⁻¹). The bacterial diversity in P. conjugatum-restored soil was higher than that in soil of P. massoniana. The bacterial genera Chloroflexi, Acidobacteria, and Actinobacteria were predominant in the restored soils. P. conjugatum was tolerant to drought and exhibited enhanced enzymatic activity. These results suggest that P. conjugatum can be used for efficient phytoremediation of Pb- and Cd-contaminated soils.

稀土元素的过度开采会导致稀土矿尾矿中的镉（Cd）和铅（Pb）污染。在这里，Paspalum conjugatum被用作多年生高积累草本植物，以评估其在水培试验中去除金属的植物提取潜力。此外，为期两年（2016-2018年）进行了原位实验，以研究共轭假单胞菌降低土壤金属浓度的潜力，并评估了废弃稀土矿区微生物组的恢复情况。马尾松用于对照治疗。我们发现，共轭假单胞菌对Cd和Pb的金属转移系数分别为0.85和0.89。镉和铅的积累共轭假单胞菌分别为98.33 mg kg ^-1和137 mg kg ^-1。使用P. conjugatum，土壤中Pb和Cd浓度显着降低，Cd浓度达到可接受水平（0.209 mg kg ^-1）。修复后的共轭土壤中的细菌多样性高于马尾松土壤中的细菌多样性。在恢复的土壤中，主要的细菌属有绿弯曲菌，酸性细菌和放线菌。P。接合处对干旱具有耐受性，并表现出增强的酶活性。这些结果表明P. conjugatum可用于对Pb和Cd污染的土壤进行有效的植物修复。