Remote sensing-based assessment of forest loss and fragmentation in Bhawal National Park, Bangladesh

Abstract

Bhawal National Park (BNP), located in central Bangladesh, is a key ecological region that has experienced significant degradation over recent decades due to industrial expansion and increasing human settlement. This study uses geospatial analysis of Landsat satellite imagery from 1990 to 2020 to investigate patterns of deforestation, forest degradation, and fragmentation within the park. A post-classification comparison approach, incorporating a random forest algorithm, was applied, followed by a forest fragmentation assessment using the Landscape Fragmentation Tool. The results reveal substantial changes in land cover over the study period. Dense forest area decreased by 225.45 hectares (24.9%), and medium forest by 485.01 hectares (31.6%), while industrial and urban areas expanded dramatically, surging from 18 ha (0.19%) in 1990 to 1,329 ha (13.97%) in 2020, reflecting an extraordinary annual growth rate of 240.46%. Although the park gained 762.21 hectares of forest, it simultaneously lost 1,655.73 hectares of other forest types. Forest fragmentation intensified, with the number of forest patches nearly doubling, leading to significant changes in patch distribution, edge conditions, and perforated forests, further impacting the park’s ecological stability. The study integrates a Socio-Ecological Systems (SES) framework to inform restoration and conservation planning. The results might help inform policy action and strategic management to protect the park’s ecological integrity, providing essential guidance for sustainable forest conservation in Bangladesh.