Sarkar Showmitra Kumar, Saroar Mustafa, Chakraborty Tanmoy
Department of Urban and Regional Planning, Khulna University of Engineering & Technology (KUET), Khulna, 9203, Bangladesh.
Heliyon. 2023 Jul 13;9(7):e18255. doi: 10.1016/j.heliyon.2023.e18255. eCollection 2023 Jul.
The Rohingya crisis in Myanmar's Rakhine state has resulted in a significant influx of refugees into Cox's Bazar, Bangladesh. However, the ecological impact of this migration has received limited attention in research. This study aimed to address this gap by utilizing remote sensing data and machine learning techniques to model the ecological quality (EQ) of the region before and after the refugee influx. To quantify changes in land use and land cover (LULC), three supervised machine learning classification methods, namely artificial neural networks (ANN), support vector machines (SVM), and random forests (RF), were applied. The most accurate LULC maps obtained from these methods were then used to assess changes in ecosystem service valuation and function resulting from the land use changes. Furthermore, fuzzy logic models were employed to examine the EQ conditions before and after the Rohingya influx. The findings of the study indicate that the increased number of Rohingya refugees has led to a 9.58% decrease in forest area, accompanied by an 8.25% increase in settlement areas. The estimated total ecosystem services value (ESV) in the research area was $67.83 million in 2017 and $67.78 million in 2021, respectively. The ESV for forests experienced a significant decline of 21.97%, equivalent to a decrease of $5.33 million. Additionally, the reduction in forest lands has contributed to a 13.58% decline in raw materials and a 14.57% decline in biodiversity. Furthermore, utilizing a Markovian transition probability model, our analysis reveals that the EQ conditions in the area have deteriorated from "very good" or "good" to "bad" or "very bad" following the Rohingya influx. The findings of this study emphasize the importance of integrating ecological considerations into decision-making processes and developing proactive measures to mitigate the environmental impact of such large-scale migrations.
缅甸若开邦的罗兴亚危机导致大量难民涌入孟加拉国的科克斯巴扎尔。然而,这一移民潮对生态的影响在研究中受到的关注有限。本研究旨在通过利用遥感数据和机器学习技术,对难民涌入前后该地区的生态质量(EQ)进行建模,以填补这一空白。为了量化土地利用和土地覆盖(LULC)的变化,应用了三种监督式机器学习分类方法,即人工神经网络(ANN)、支持向量机(SVM)和随机森林(RF)。然后,使用从这些方法中获得的最准确的LULC地图来评估土地利用变化导致的生态系统服务估值和功能的变化。此外,还采用模糊逻辑模型来研究罗兴亚人涌入前后的EQ状况。研究结果表明,罗兴亚难民数量的增加导致森林面积减少了9.58%,定居面积增加了8.25%。研究区域的估计生态系统服务总价值(ESV)在2017年为6783万美元,在2021年为6778万美元。森林的ESV大幅下降了21.97%,相当于减少了533万美元。此外,林地的减少导致原材料减少了13.58%,生物多样性减少了14.57%。此外,利用马尔可夫转移概率模型,我们的分析表明,罗兴亚人涌入后,该地区的EQ状况已从“非常好”或“好”恶化到“差”或“非常差”。本研究结果强调了将生态因素纳入决策过程以及制定积极措施以减轻此类大规模移民对环境影响的重要性。