Resistance and Resilience of Vegetation and Microclimate along the Subtropical Expressway via Remote Sensing

Evaluating vegetation resistance and resilience is key to understanding ecosystem responses to human disturbances such as road construction and to guiding ecological restoration. This study systematically assessed the resistance and resilience of vegetation and microclimate along the Hangrui Expressway in southwestern China using remote sensing techniques. Landsat imagery from 10 representative years between the preconstruction period (1993) and the recovery period (2021) was analyzed, with indicators such as the normalized difference vegetation index, surface temperature, and evapotranspiration used to characterize vegetation and microclimate. The study area was divided into 200-m buffer zones, and resistance–resilience indicators were developed to reveal spatial distribution patterns. In addition, an optimized “forest–grassland ratio” was proposed to guide vegetation configuration strategies, effectively promoting the enhancement of both vegetation and microclimate resilience. Structural equation modeling identified the key factors influencing roadside vegetation resistance and resilience. The results showed that most areas exhibited strong resistance and resilience, enabling rapid recovery after disturbances. Vegetation typically required about 4 years to recover, while surface temperature and evapotranspiration required 7 and 2 years, respectively, to return to predisturbance levels. Topographic factors were significantly positively correlated with microclimate resilience, while climate factors were positively correlated with microclimate resilience but negatively correlated with vegetation resilience. Climate and topography were the main influencing factors. The optimal forest–grassland ratio varied across different regions. These findings underscore the importance of considering local climatic and topographic conditions in road planning and ecological restoration to improve restoration outcomes and promote ecosystem stability.