Fragmentation Analysis to Quantify the Changes in Forest Cover after the Massive Rohingya Refugee Influx in Bangladesh

Abstract

Abstract This study aims to quantify the changes in forest cover in the Rohingya refugee camp areas after the highest influx of refugees. Rohingya refugee migration in 2017 broke the previous records when hundreds of thousands of people fled to Bangladesh with the hope of saving their lives. To respond to this humanitarian emergency, densely populated Bangladesh had few choices other than to clear a forest area to make temporary shelters for Rohingya refugees. Hence, this study applied land use land cover classification techniques, and fragmentation analysis to detect and quantify the changes occurred because of sudden migration. Sentinel 2 images for 2016 and 2022 were classified into four classes: Forest, Water, Agriculture/Open field, and Settlement. Moreover, considering spatial aspects, landscape patterns were analyzed based on seven class-level metrics and two landscape-level metrics. From 2016 to 2022, results showed a decline in total forest areas from 1581 to 737.01 hectares, whereas settlement areas increased (3.71 to 63.09%) dramatically after the establishment of new camps. An increase in the number of patches (804 to 2642), patch density (32.2 to 105.83), and division index (0.81 to 0.99) for the Forest class indicates that the forest area became more fragmented in 2022 than in 2016. In addition, landscape-level metrics revealed an increase in the number of patches, and patch densities also exhibited fragmented landscape in 2022. Over the last six years, the establishment of refugee camps has noticeably changed the landscape and created adverse effects on agriculture, water resources, and ecosystem balance.