Modelling of urban land-use and land-cover and urban sprawl in the Siliguri Urban agglomeration: a geospatial analysis

Abstract

The largest urban agglomeration in North Bengal is in Siliguri, which has experienced fast peri-urban expansion and a steady loss of natural environment due to the city’s rapid urbanization and migrant influx over the past three decades. This study examines the relation between built-up area and population in the Siliguri Urban Agglomeration as well as the spatiotemporal dynamics of landuse/landcover changes during for 2031, 2041, 2051, and 2100 using a number of driving variables. Additionally, to illustrate urban sprawl, Shannon’s entropy approach has been used to estimate built-up expansion, and the integrated cellular automata (CA)-Markov model was used to predict future land use/land cover scenarios. The results indicate that vegetation and agricultural land would decrease as a result from 1991 to 2100, from 9.19 km2 in 1991 to 73.62 km2 in 2100. Over the next 110 years, a large increase is anticipated in the built-up area, from 7.43% of the total land use area to 61.62%. In addition, the results suggest that between 1991 and 2021, the built-up area significantly increased from 9.63 km2 to 49.25 km2, while agricultural land and vegetation cover decreased by 13% and 50%, respectively. The percentage growth of intra-district in-migration to the Siliguri urban agglomeration was also observed to increase by 170% from 31% between 1991 and 2021, which put a lot of pressure on urban land and transformed agricultural and vegetated land into built-up areas. According to the gain and loss technique, agriculture and vegetation suffered the greatest losses, at 36.16 km2 and 29.79 km2, respectively. The population in 1991 was estimated to be 364,000 according to census statistics and Landsat pictures, although the built-up area was just 9.19 km2. The predicted population increase within 30 years was 1,050,000, and the built-up area was 49.25 km. As a result, in the next days, this city may turn into an urban heat island. The results of this study will assist policymakers in creating management strategies for environmentally friendly and orderly urban expansion.