Objective Scientifically evaluating vegetation growth and human disturbances in nature reserves is crucial for assessing regional sustainable development. This evaluation is important for ensuring the sustainable development of nature reserves and strengthening the national ecological security barrier.

Methods This study focused on three national nature reserves in Xinjiang (Hanas, West Tianshan, and Tomur Peak). Using indicators such as Fractional Vegetation Cover (FVC), Net Significant Growth Rate (NSGR) of vegetation, and Human Disturbance (HD), we employed trend analysis and driving force analysis to comprehensively analyze changes in vegetation and human disturbances within the reserves from 2001 to 2020. Additionally, a driving force analysis of the changes in vegetation coverage was conducted.

Results The results indicated that: (1) Regarding FVC, from 2001 to 2020, all reserves exhibited higher FVC compared to the surrounding regions, with more stable FVC within the reserves. The West Tianshan reserve had the highest average FVC (0.77±0.04), followed by Hanas and Tomur Peak, with Tomur Peak showing the most rapid growth. (2) In terms of NSGR, the reserves exhibited higher rates in comparison to the surrounding regions, with Tomur Peak having the highest NSGR at 37.87%, followed by the Hanas and West Tianshan reserves. (3) For HD, all three reserves showed significant declines, with Hanas having the least HD throughout, while Tomur Peak experienced the most pronounced reduction, with an 86.98% decrease over the twenty years. (4) The alteration in vegetation coverage within the reserves and surrounding areas were jointly influenced by the concentrations of CO₂, the phenomenon of climate change, and the modifications in land cover. Vegetation cover change was the primary factor affecting coverage changes in both the reserves and surrounding areas (contributing over 50% in all areas).

Conclusions Overall, vegetation growth in the three nature reserves has either increased significantly or remained stable, indicating good ecological protection effectiveness. However, a few areas have shown significant declines in FVC, necessitating enhanced monitoring and management.