植物修复是修复金属污染土壤的有效途径。在植物修复过程中,植物通过根部固定重金属以减少流动性,金属的毒性和分散性,根系活动的变化往往伴随着根际生态系统的变化,其中根际细菌是必不可少的组成部分,并与根相互作用,以维持根际生态系统的稳定并改善土壤健康。在这项研究中,Sasaargenteostriata(Regel)E.G.的植物修复潜力。不同水平的铅锌尾矿污染揭示了Camu和根瘤菌的响应(Pb,Zn,和M1的Cd浓度分别为1197.53、3243.40和185.44mg/kg,M2的浓度分别为2301.71、6087.95和364.00mg/kg)。Sasaargenteostriata的BCF随土壤污染的增加而增加,和BCFPb,BCFZn,和BCFCd分别为0.19、0.27和0.08,在M2处理下;相比之下,TF随着土壤污染的增加而降低,和TFPb,TFZn,和TFCd分别为0.39、0.85和0.07,在M1治疗下。Pb在根际的迁移率高于Zn和Cd,根际中残留锌和镉的百分比增加,而酸溶性(Aci)Pb明显更高,导致根部明显吸收Pb。相关分析表明,根际土壤pH值的变化对根际细菌群落的影响,有机物和NRFM的含量,和细菌,如变形杆菌和MND1,它们对重金属(HM)具有高度抗性,成为群落中的优势物种。进一步的PICRUSt2分析表明,减少金属跨膜转运和提高细胞繁殖效率是细菌对HMs耐受的主要代谢机制。Sasaargenteostriata的根能够在PbZn尾矿污染的土壤中固定更多的重金属,降低HMs在土壤中的毒性,然后影响根瘤菌改变群落结构和代谢机制以适应HM污染的环境,土壤肥力增加了,它们共同促进了土壤的健康和稳定。这项研究首次说明了在PbZn尾矿的多金属污染下,Sasaargenteostriata根瘤菌群落的植物修复潜力和响应。研究结果为铅锌尾矿植物修复和土壤健康的实践提供了一定的指导。
Phytoremediation is an effective way to remediate metal-contaminated soils. During phytoremediation, plants immobilize heavy metals through the roots to reduce the mobility, toxicity and dispersal of the metals, and the changes in the activity of the roots are often accompanied by changes in the rhizosphere ecosystems, in which rhizobacteria are essential components and interact with roots to maintain the stability of the rhizosphere ecosystem and improve soil health. In this study, the phytoremediation potential of Sasa argenteostriata (Regel) E.G. Camu and the response of rhizobacteria were revealed with different levels of lead-zinc tailing contamination (Pb, Zn, and Cd concentrations of 1197.53, 3243.40, and 185.44 mg/kg for M1 and 2301.71, 6087.95, and 364.00 mg/kg for M2, respectively). The BCF of Sasa argenteostriata increased with increasing soil pollution, and the BCFPb, BCFZn, and BCFCd were 0.19, 0.27, and 0.08, respectively, under the M2 treatment; in contrast, the TF decreased with increasing soil pollution, and the TFPb, TFZn, and TFCd were 0.39, 0.85, and 0.07, respectively, under the M1 treatment. The mobility of Pb in the rhizosphere was higher than that of Zn and Cd, and the percentage of residual (Res) Zn and Cd in the rhizosphere increased, while the acid-soluble (Aci) Pb was significantly higher, leading to obvious uptake of Pb by the roots. Correlation analysis showed that Sasa argenteostriata affected the rhizobacterial community by changing the rhizosphere soil pH, the contents of organic matter and NRFM, and bacteria such as Proteobacteria and MND1, which are highly resistant to heavy metals (HMs), became the dominant species in the community. Further PICRUSt2 analysis showed that reducing metal transport across the membranes and increasing the efficiency of cellular reproduction were the main metabolic mechanisms of bacterial tolerance to HMs. Overall, the roots of Sasa argenteostriata were able to immobilize more heavy metals in PbZn tailing-contaminated soil, reducing the toxicity of HMs in the soil, and then influencing the rhizobacteria to change the community structure and metabolism mechanism to adapt to the HM-contaminated environment, and the soil fertility was increased, which together promoted the health and stability of the soil. This study is the first to illustrate the phytoremediation potential and response of the rhizobacterial community of Sasa argenteostriata under multimetal contamination of PbZn tailings. The results of the study provide some guidance for the practice of lead-zinc tailing-phytoremediation and soil health.