Sustainable urban expansion and land use dynamics in North Bengal's urban and peri-urban areas: A trajectory-based forecasting approach

Rapid urbanisation is reshaping landscapes worldwide, with peri-urban areas facing especially intense pressure as cities expand outward. According to the United Nations' World Urbanisation Prospects, the global urban population is projected to rise from 30 % in the 1950s to 66 % by 2050, underscoring the urgent need to understand and sustainably manage urban land transformations. This research examines the spatial and temporal patterns of land use and land cover (LULC) changes in Siliguri, the largest urban agglomeration in North Bengal, focusing on the interaction between urban and peri-urban expansion and the decline of agricultural land. The CA-Markov Chain model was used to forecast LULC patterns up to 2100 with over 90 % accuracy. The study first assessed the urban extent of Siliguri Urban Agglomeration (SUA) and, using a 12.5 km buffer from the urban centroid, identified 110 adjacent villages across Darjeeling and Jalpaiguri districts. From these, four representative peri-urban villages Mahanbhita, Araji Binnaguri, Bataliguri, and Kadmi were selected for detailed spatial analysis, ensuring a comprehensive understanding of peri-urban transformation patterns. Our findings reveal dramatic increases in built-up areas—rising from 12.98 % to 43.19 % within Siliguri Urban Agglomeration—and a steep decline in agricultural land, which fell from 34.76 % to 17.26 %. Peri-urban zones showed even more rapid shifts, with built-up land surging from 1.30 % to 20.81 % and agricultural areas shrinking from 39.98 % to 13.59 %. Vegetation and tea gardens also experienced notable changes, particularly in key transition zones like Binnaguri and Chakiabhita. By identifying the specific spatial directions and hotspots of expansion, this research offers critical insights into the sustainability challenges posed by unplanned urban growth. The study highlights the urgent need for integrated land management and urban planning strategies to balance development pressures with the preservation of agricultural and ecological resources. Our results provide policymakers and urban planners with a science-based framework to guide sustainable city expansion, protect peri-urban ecosystems, and enhance climate resilience. • A CA-Markov Chain model accurately forecasted land use change in Siliguri Urban Agglomeration and peri-urban areas up to 2100 with over 90 % accuracy. • Built-up area in Siliguri increased sharply from 12.98 % to 43.19 %, while agricultural land declined from 34.76 % to 17.26 % between 1990 and 2022. • Peri-urban zones experienced rapid transformation, with built-up land rising from 1.30 % to 20.81 % and agricultural land shrinking from 39.98 % to 13.59 %. • Transition zones such as Binnaguri and Chakiabhita showed significant changes in vegetation and tea garden land use, indicating ecological stress. • The study identifies urban expansion hotspots and provides a spatially-informed framework for sustainable land management and climate-resilient urban planning.