Assessing land use change and potential environmental quality in Chandernagore Municipal Corporation, India

The study has focused on portraying the spatio-temporal changes in land use pattern from 2011 to 2019 and has tried to assess the environmental quality index (EQI) based on the classified images of Chandernagore Municipal Corporation (CMC). To conduct the present research, satellite imageries of IRS Resourcesat-2 LISS-IV Mx (November 2011) and Sentinel-2A (November 2019) have been used. Supervised image classification approach with maximum likelihood classification has been adopted for the generation of land use maps. A total of 404 sample verification points has been taken to assess the accuracy of land use classification in both cases. The verification points have been selected by purposive random sampling method throughout the images. An initial statistical analysis and detailed principal component analysis (PCA) were performed to construct the EQI for the study region. This was followed by a spatial mapping and analysis to provide a better understanding of the status of the environmental quality to the planners and policy-makers. Results reveal the consistent increase in area under built-up (+ 14%) and brick kiln/industry (81%) and continuous decrease in orchard (- 10%), forest (- 10%) and open space (- 21%). The overall classification accuracy was found 90.10% (2011) and 93.32% (2019). The total Kappa coefficient is quite satisfactory for 2011 (0.86) and is almost perfect in 2019 (0.91). With more than 85% explanation within first three components in PCA (2011 and 2019, eigenvalue > 1), the EQI map is clearly portraying that the western part of CMC is still breathing in fresh air with better environmental quality but the recent phase of expansion and process of urban sprawl has evidently swallowed up the expensive land in eastern part of the city and gradually spreading towards the west.