Integrated Environmental Assessment of Coastal Villages in Thoothukudi District: A Geospatial Approach for Sustainable Coastal Management

Abstract

Coastal environments face unprecedented environmental pressures from urbanization, climate change and anthropogenic activities necessitating comprehensive integrated assessments for sustainable management. The study presents a comprehensive integrated environmental assessment of Thoothukudi District, Southern India utilizing hybrid TOPSIS-AHP multi-criteria decision analysis integrated with Google Earth Engine cloud computing to evaluate flood hazard, groundwater potential, land surface temperature and urban heat island dynamics. Technical assessments integrated twelve hydrological, topographic, geological and environmental parameters across coastal plain. Flood hazard assessment identified 64.50% (650.91 km²) moderate hazard coverage, 32.37% (326.62 km²) low hazard zones and 3.13% (31.61 km²) high hazard clusters concentrated near coastal villages. Groundwater potential mapping revealed 41.4% (405.37 km²) very high potential zones and 39.45% (386.24 km²) good potential areas supporting water-use efficiency and ecosystem protection. Land surface temperature analysis for 2025 documented pronounced seasonal variability with monsoon LST of 51.8°C, summer 39.4°C and winter 30.8°C, with spatial extremes ranging 9-78°C. Urban heat island intensity averaged 3.26°C in summer, 3.47°C during monsoon and 2.68°C in winter, with maximum values exceeding 24.93°C in urban cores. LULC classification revealed cropland dominance (487.0 km², 48.3%), built-up areas (164.92 km², 16.35%) and scrubland (197.82 km², 19.61%). Composite vulnerability assessment identified low vulnerability zones occupying 88.14% (889.46 km²), moderate vulnerability 11.17% (112.71 km²) and high vulnerability 0.69% (6.97 km²) concentrated in coastal villages. The integrated framework provides spatially explicit evidence supporting SDGs 6, 11, 13, 14 and 15 enabling evidence-based coastal zone management, climate adaptation planning and sustainable development pathways.