Spatio-Temporal Dynamics of Forest Cover and Climatic Variability in Lohit District, Arunachal Pradesh (1988–2023)

Understanding long-term forest dynamics and their climatic controls is critical for managing ecologically sensitive mountain landscapes. This study examines spatio-temporal forest cover change and associated climatic variability in Lohit District, located within the Eastern Himalayan biodiversity hotspot, over a 35-year period (1988–2023). Multi-temporal Landsat imagery was used to derive the Normalized Difference Vegetation Index (NDVI) and Land Surface Temperature (LST), which were integrated with long-term gridded rainfall data from the India Meteorological Department to assess vegetation transitions and climate–vegetation interactions. The results reveal pronounced structural degradation of forest ecosystems rather than large-scale deforestation. Dense forest cover declined sharply from 3,122.39 km² (70.05%) in 1988 to 908.35 km² (20.38%) in 2023. This loss was accompanied by substantial expansion of moderate forest and shrub–grassland classes, indicating widespread canopy thinning, fragmentation, and secondary succession. Climatic analysis shows a significant decline in precipitation, with minimum annual rainfall decreasing by approximately 67%, alongside progressive surface warming, reflected in increases in both minimum and maximum LST. Spearman’s rank correlation analysis demonstrates a strong positive relationship between NDVI and rainfall and a strong negative relationship between NDVI and LST, highlighting the coupled influence of hydroclimatic stress and land-cover change on vegetation dynamics. The interaction of declining rainfall, rising surface temperatures, and sustained anthropogenic pressures particularly timber extraction, shifting cultivation, and infrastructure expansion has constrained forest recovery and reinforced degraded forest states. The findings underscore the vulnerability of Eastern Himalayan forests to compound climatic and human pressures and emphasize the need for climate-integrated, ecosystem-based forest management. Long-term satellite-based monitoring combined with hydroclimatic assessment provides a robust framework for guiding adaptive conservation strategies and enhancing ecological resilience in climate-sensitive mountain regions.