ABSTRACT
The Kolkata Municipal Corporation has been undergoing the process of rapid urbanization over the last few years to meet the needs and demands of the people. With change over time, there has been large-scale change within the municipal area with increasingly built up and residential areas. However, this increasing trend of urbanization has also brought about an increase in the urban heat island effect and a decrease in the health of vegetation of the study area. An attempt has been made in this paper to analyze the relationship between urbanization, urban heat island, and vegetation health of the study area through Markov chain analysis and the geospatial technique on a temporal scale for the years 1999, 2009, 2019, and 2022. In the present paper, computation of normalized difference vegetation index (NDVI), normalized difference built-up index (NDBI) and land surface temperature (LST) values have been done using Landsat 5 TM and Landsat 7 ETM+ satellite images for the years under investigation. The Markov chain model also focused on the probable trend of urban concentration in the study area for the time period of the last 24 years, i.e., from 1999 to 2022. The study reveals that there has been a continuous decline in the NDVI values from 1999 to 2019 and a slight improvement in 2022 owing to lower pollution levels due to the lockdown in 2020 and 2021 for COVID-19 pandemic. However, the trend of vegetation health has exhibited a declining trend from 1999 to 2022. There has also been a rise of NDBI values for the subsequent years indicating an increase in urbanization along with an increase in urban heat island phenomena. The study also highlights that there exists a negative relationship between urbanization and vegetation health, a positive relation between urbanization and urban heat island effect, and a negative relation between vegetation health and urban heat island effect. To mitigate the problem of urbanization, there is a need for proper balanced planning within the municipal corporation area for the creation of a better city for the future generations.
