Geospatial Assessment of Soil Salinity in an Urban Coastal Environment: A Case Study of Chennai Metropolitan Region, Southern India

作者：Sridhar Sundaramoorthy, P. Moorthy, Ahamed Ibrahim Abdul Rahim, L. Chokkalingam · 发表于：Disaster Advances · 年份：2025 · DOI：10.25303/1812da059070

Soil salinization is a growing environmental issue in coastal urban regions, impacting land productivity, vegetation health and infrastructure. This study provides a geospatial assessment of soil salinity across the Chennai Metropolitan Region using multi-temporal Landsat 8 OLI imagery and spectral salinity indices. Thirteen indices including SI, SI1–SI4, SR, RSI, MSR, NDSI, NDVI, GNDVI, SAVI, DVI, VSSI and EVI were used to capture surface reflectance and vegetation degradation. An integrated machine learning-based overlay analysis using Random Forest (RF) classified salinity into five categories: very low, low, moderate, high and very high. Results indicate that the northern coastal belt of Chennai, especially areas near the Bay of Bengal, falls under high to very high salinity due to tidal intrusion, urbanization and inadequate drainage. Inland zones like Madhavaram, Ambattur, Alandur, Guindy, Velachery and Sholinganallur showed low to moderate salinity levels. Landuse Land Cover (LULC) data for 2025 was incorporated to examine spatial correlations between salinity and urban expansion. This study highlights the effectiveness of combining spectral indices with machine learning to identify salinity hotspots and support informed urban planning and sustainable land management in vulnerable coastal megacities.