Impact of Urban Expansion on Wetlands: A Case Study of Bhoj Wetland, India

Wetlands play an important role by providing multidimensional ecosystem services to the society. In recent decades, the world has experienced tremendous urban expansion, posing threats to wetland ecology. To comprehend and evaluate these threats, a study was conducted in the Bhoj wetland of Bhopal, India. In 2002, the Ramsar convention designated the Bhoj wetland, which includes Upper and Lower Lake, as a wetland of international importance. The Upper Lake serves as the city's lifeline and provides 40% of the potable water used in the city. However, this wetland has faced anthropogenic threats in recent decades. The purpose of this study was to map and monitor the vulnerable areas around the Bhoj wetland and assess the changes over a period of 30 years. Remote sensing and geographic information system methods were used in this study to identify changes in land use and land cover (LULC) patterns for the years 1990, 2000, 2013, and 2020. The maximum likelihood classifier was used in supervised classification to create the LULC maps. The result showed that Built-up, Barren land, and Marshy land increased by 16.97 percent, 4.79 percent, and 0.7 percent, respectively, while Agricultural land, Vegetation, and Water bodies decreased by 11.84 percent, 10.5 percent, and 0.13 percent, respectively, from the year 1990-2020. The outcome of this study showed the vulnerable areas in the wetland catchment by change assessment in LULC, drainage density and land fragmentation. This would guide future urban development policy for LULC management, considering the wetland protection goals.