Geospatial driven machine learning approach for flood susceptibility mapping in southeastern region of Bangladesh
摘要
Floods are a major threat to life, infrastructure and livelihoods in Bangladesh, especially in low-lying and rapidly urbanising coastal areas. This study assesses the effectiveness of Random Forest (RF) and Maximum Entropy (MaxEnt) models in mapping flood susceptibility in the Fens district in southeastern Bangladesh, using 14 flood control factors, including topographic, hydroclimatic, soil and spectral variables, embedded in Google Earth. Flood and non-flood inventory points were randomly allocated to the training (80%) and validation (20) datasets. All predictor variables had a tolerance value above 0.20, which indicates a low multilinearity. The performance of the model was evaluated by using accuracy, precision, recall, F1 score, and metrics ROC-AUC. Both models had strong predictive power: MaxEnt had a superior discriminative capability (AUC = 0.98) and a higher recall, while RF had a higher overall accuracy (0.93), a precision (0.92), and a F1 score (0.95). The models differed in the distribution of sensitivity classes: RF predicted the highest suitability in medium (329.08 km²) and low (324.35 km²), while MaxEnt predicted the lowest suitability in medium (365.86 km²) and low (337.0 km2), with a minor (17.11 km2) and very high suitability in the middle class. These findings demonstrate the value of machine learning-based flood susceptibility mapping in data-poor environments, providing critical information for disaster preparedness, spatial planning and early warning systems, but underline that areas close to the threshold should be interpreted with caution because of possible uncertainties in classifications.