"International Journal of Geography, Geology and Environment"
2025, Vol. 7, Issue 7, Part A
Mapping urban stress and green depletion in Shimla using remote sensing: A step towards sustainable urban future
Author(s): Paritosh Thakur and Sunil Jaswal
Abstract: The tracking of vegetation dynamics and urban growth is necessary for ecologically sound environmental planning, especially in ecologically vulnerable areas such as Himachal Pradesh. This paper provides a detailed examination of the seasonal correspondence between NDVI (normalized difference vegetation index) and NDBI (normalized difference Built-up index) from 2019 to 2024 based on Sentinel-2 imagery, chosen for its high spatial resolution and regular availability from 2019. A total of 50,000 spatially distributed but fixed points were analyzed across all districts of Himachal Pradesh. Karl Pearson's correlation coefficient was calculated season-wise by Python to reflect the relationship between NDVI and NDBI, which indicated a persistent negative correlation pattern, mainly in urbanizing areas. Time series and trend analysis were undertaken to evaluate long-term vegetation and built-up pattern changes, with a linear regression model used to project trends up to 2030. Findings show an evident seasonally related reduction in vegetation cover that parallels urban growth in major districts. Further, a heatmap of correlations was created to display spatial variation in the relationship between NDVI-NDBI, emphasizing ecological hotspots as well as zones of significant transition. This research offers policy-relevant findings for policymakers and urban planners in that it maps out regions most impacted by anthropogenic pressure and climatic variability in the Western Himalayan environment.
Paritosh Thakur, Sunil Jaswal. Mapping urban stress and green depletion in Shimla using remote sensing: A step towards sustainable urban future. Int J Geogr Geol Environ 2025;7(7):32-39. DOI: 10.22271/27067483.2025.v7.i7a.383
