A comparative analysis of urban environmental quality of developing cities of India: A geospatial approach

Excessive growth in the global human population and eventually urbanisation has become a serious threat to the environment. These situations arise especially in the rapidly developing nations, India being one of them. A higher population naturally poses a high pressure on the environment directly or indirectly, which is a threat for the sustainable development of the country. Most Indian cities face environmental sustainability challenges. Most cities in India are presently going through rapid urbanization and industrialization which leads to environmental degradation of the city. The objective of this study is to analyse the environmental quality of the selected developing cities and also compare the intensity to which they are affected by urbanisation. The study is performed using satellite-based remote sensing data. Initially, Landsat data is used for the years 2001 to 2021 and is utilized for studying the LULC (land use land cover) transformations. MODIS data products are used at 1 km resolution to extract the biophysical indicators (BI) such as normalized difference vegetation index (NDVI) and land surface temperature (LST). MODIS data for PM2.5 is also utilised and finally, an index is calculated to represent the comprehensive environmental quality of the selected cities (CEQI). The yearly and decadal changes in the values of this index is mapped. The LULC transformations depicted a phenomenal decay in the greenness and an increase in the urban built-up area of the city. The CEQI variations and temporal trends reveal the significant deterioration of the overall environmental conditions in most of the cities. This is due to the change in gentrification patterns and also the change in urbanization and the greenness of the city. The study suggests that emission control strategies and urban greening can significantly contribute to enhancing urban environmental quality, especially in rapidly developing cities. The measures suggested to improve the environmental quality can help the policy-makers in the sustainable planning of the city.