Ecotoxicological Impacts of Heavy Metals on Medicinal Plant Quality and Rhizosphere Microbial Communities

With the rapid expansion of industrial activities, the accumulation of heavy metals in the environment has become a serious threat to ecological security and public health. Rhizosphere microorganisms play a crucial role in supporting the growth and quality of medicinal plants by facilitating nutrient uptake and regulating hormonal balance. However, medicinal plants can absorb heavy metals from contaminated soils during growth, resulting in toxic metal accumulation in plant tissues and reduced efficacy of active compounds. At the same time, excessive heavy metal levels suppress rhizosphere microbial growth and activity, disrupt community structure and function, and weaken their beneficial interactions with plants. These processes collectively lead to soil fertility decline, hindered plant development, and compromised safety and quality of medicinal materials. This review systematically summarizes the mechanisms by which heavy metals affect medicinal plants and their rhizosphere microbiota, and highlights that future research should focus on elucidating these interactions, developing advanced remediation technologies, and establishing comprehensive monitoring systems for the quality and safety of medicinal plants, thereby providing a scientific basis for their safe utilization and quality improvement.