Quantifying the spatiotemporal patterns of forest degradation in a fragmented, rapidly urbanizing landscape: A case study of Gazipur, Bangladesh

The rapidly growing population of Bangladesh is significantly influencing forest degradation. Recent economic development and industrialization in Gazipur, a district adjacent to the capital, Dhaka, has further aggravated this situation. Therefore, the purpose of this study was to understand the causes of forest degradation in Bangladesh using Gazipur as a case study. The forest land conversion was evaluated in this district using supervised classification with the Random Forest algorithm based on Landsat images from 2002, 2007, and 2015. This data was used to conduct a land conversion analysis to study the relative changes in the defined classes. In the study, built-up areas, trees outside forest, and cropland areas increased by 654.38%, 87.44%, and 40.71%, respectively, while forest, waterbody, and fallow land areas decreased by 62.67%, 54.10%, and 46.95%, respectively. The land cover change analysis revealed that forest areas, particularly those dominated by the threatened sal tree (Shorea robusta), were converted into other land-use classes. Bangladesh-specific development indicators from the World Bank were also incorporated into the study to better understand the underlying situation. The results support the formation of policies and planning to reverse forest degradation as per the Paris Climate Agreement and Sustainable Development Goals. Such environmental degradation should be considered by the government and development agencies as a critical issue in Bangladesh, where more sustainable forest resource management is needed to achieve forest degradation neutrality.