Urbanization, Ecological Impact, and Air Quality: Insights from LULC Dynamics in Gandhinagar Using Satellite Data and Geospatial Analysis

Abstract

Urbanization is a critical driver of environmental change, significantly impacting air quality and Land Use/Land Cover (LULC) dynamics. This study aims to investigate the relationship between LULC changes and air quality in Gandhinagar, India, utilizing satellite-based datasets from Landsat-8 and Sentinel-5P. The key pollutants, including carbon monoxide (CO), nitrogen dioxide (NO2), methane (CH4), sulphur dioxide (SO2), and formaldehyde (HCHO) were monitored over the years 2018, 2020, 2022, and 2024. The research employs Google Earth Engine (GEE) for comprehensive spatial-temporal analysis, revealing fluctuating pollutant concentrations: CO levels ranged from 0.03432 to 0.04075 mol/m2, NO2 varied between 0.0000709 and 0.0001346 mol/m2, CH4 increased from 1847.42 to 1945.85 ppb, SO2 fluctuated between 0.0000425 and 0.0004961 mol/m2, and HCHO levels ranged from 0.0001352 to 0.0002511 molecules/cm2. Notably, the COVID-19 lockdown in 2020 led to a temporary but significant reduction in pollutants compared to pre-lockdown levels: CO dropped by ~7.2%, NO₂ by ~21.4%, SO2 by ~64%, and HCHO by ~16.8%. These reductions are attributed primarily to decreased human activity rather than changes in LULC, which is validated by the minimal LULC transformation observed during the same period. The results highlight the socio-economic implications of air quality degradation, particularly concerning public health and urban sustainability, aligning with the United Nations Sustainable Development Goals (SDGs), specifically Goal 11 (Sustainable Cities and Communities) and Goal 3 (Good Health and Well-being). The work emphasizes the need for integrated urban planning strategies that incorporate green infrastructure and stricter emission controls. By establishing correlations between LULC dynamics and air quality, this paper provides actionable insights for policymakers and urban planners, contributing to sustainable land management practices and enhancing the resilience of rapidly urbanizing regions like Gandhinagar. This study serves as a model for similar assessments in other urban contexts, promoting a data-driven approach to address the challenges of urbanization and climate change to stabilize the ecological balance.