THE ROLE OF DHANMONDI LAKE IN ENHANCING ENVIRONMENTAL QUALITY AND SUSTAINABLE RECREATIONAL TOURISM IN DHAKA

Abstract

Rapid urbanization in tropical megacities has intensified environmental degradation, leading to deteriorating air quality, altered microclimates, and declining green cover, all of which directly affect the environmental comfort and recreational suitability of urban leisure spaces. Dhaka, where particulate matter levels frequently exceed World Health Organization guidelines and green cover has significantly declined, represents a critical case of environmental stress in a high-density tropical setting. This study examines urban green–air interactions and their implications for environmental quality, atmospheric health, and visitor experience around Dhanmondi Lake, a prominent urban recreational landscape in Dhaka, over a decadal period (2015–2025). A mixed-methods framework was adopted, integrating geospatial analysis of NDVI, NDWI, and NDBI derived from Sentinel-2 imagery across 100 m, 200 m, and 300 m buffer zones, alongside high-resolution field measurements of PM1, PM2.5, PM10, temperature, and humidity. Additionally, visitor perception surveys (n=150) were conducted to assess recreational satisfaction, perceived environmental quality, and the site’s usability as an urban leisure destination. Results indicate increasing built-up expansion and declining vegetation cover, contributing to localized thermal stress and elevated pollutant concentrations. Constructed zones recorded temperatures up to 5°C higher and poorer air quality, whereas vegetated and blue-green areas exhibited cooler microclimates and improved atmospheric conditions, enhancing visitor comfort. The study underscores the diminishing yet critical role of urban green-blue recreational spaces in regulating microclimate, improving environmental health, and supporting sustainable urban tourism and visitor well-being in tropical megacities.