[Research Progress on Mechanism of Phytoremediation for Heavy Metal-contaminated Soil]

With increasing industrialization and agricultural activities， heavy metal pollution has emerged as a global environmental crisis， posing severe threats to soil quality， ecosystem functions， and biological health. Phytoremediation， as a green， cost-effective， and sustainable remediation strategy， demonstrates significant potential through plant-rhizosphere microbial systems to absorb， immobilize， or degrade heavy metals. This review systematically summarizes recent advances in phytoremediation technologies， with a focus on elucidating plant response mechanisms to heavy metal stress. Key aspects include： adaptive root architectural modifications and their interactions with rhizosphere microbial communities； root exudate-mediated regulation of metal mobilization； and physiological pathways governing heavy metal uptake， translocation， and hyperaccumulation， coupled with cellular compartmentalization and antioxidant defense strategies. The limitations of phytoremediation technology were analyzed from three aspects： restoration efficiency， application scope， and ecological risk. Further optimization strategies were proposed from aspects such as variety screening and improvement， elucidation of molecular mechanisms， plant-microbe synergistic remediation， and resource utilization， including technologies like gene editing， molecular breeding， and rhizosphere-enhanced phytoremediation. These findings provide theoretical foundations and technical pathways for soil heavy metal remediation while advancing innovative frameworks for ecological restoration and environmental governance.