Abstract: Background Soil in desert regions is highly vulnerable due to its unique ecological characteristics, making it susceptible to environmental changes and human activities. As human disturbances increase, the quality of soil in these areas continues to deteriorate, with the impact of soil heavy metal pollution on microbial community structure and diversity remaining insufficiently studied and understood. MethodsThis study focuses on the transmission tower foundation disturbance area in the Qaidam Basin, systematically investigating changes in soil chemical properties, heavy metal content, and microbial community structure and diversity in the tower foundation area and its surrounding undisturbed zones. ResultsThe results showed that transmission tower construction significantly reduced the soil pH, organic carbon, total nitrogen, total phosphorus, total potassium, and available nutrient contents, with the most significant decreased in hydrolyzable nitrogen, which dropped by 51.1%. Additionally, nutrient concentrations in shallow soils were generally higher than in deeper soils, indicating a clear soil depth gradient effect. Further analysis revealed that tower construction significantly increased the concentrations of most heavy metals in the soil, particularly in surface soils. Except for Pb and Co, the concentrations of 10 other heavy metals were significantly higher in the surface soils than in the deeper layers, with the most substantial increase observed in Fe, which rose by 123.4%. Moreover, transmission tower base construction had a pronounced impact on soil microbial community structure: in the disturbed zones, the dominant phyla were Proteobacteria, Chloroflexi, and Bacteroidetes, whereas in the undisturbed zones, Actinobacteria, Firmicutes, and Proteobacteria prevailed. Tower construction also markedly reduced the taxonomic composition and stability of the bacterial co-occurrence network. Finally, Mantel analysis further revealed that soil pH, organic carbon, hydrolyzable nitrogen, available potassium, and several heavy metal elements (such as Cr, Cd, and Fe) are the key environmental factors driving changes in microbial community structure. ConclusionsIn summary, this study provides theoretical insights and technical support for soil ecological restoration and management during transmission tower foundation construction, with significant ecological and practical implications.