Land Subsidence Susceptibility Mapping in Ca Mau Province, Vietnam Using Boosting Models

Abstract

The Ca Mau Peninsula situated in the Mekong Delta of Vietnam, features a low-lying terrain. Over recent years, the region has encountered the adverse impacts of climate change, leading to both land subsidence and rising sea levels. In this study, we assessed the land subsidence susceptibility in the Ca Mau peninsula utilizing three Boosting machine learning models: AdaBoost, Gradient Boosting, and Extremely Gradient Boosting (XGB). Eight key factors were identified as the most influential in land subsidence within Ca Mau: land cover (LULC), Groundwater levels, distance to roads, Digital Terrain Model (DTM), normalized vegetation index (NDVI), geology, soil composition, and proximity to rivers and streams.
 A dataset comprising 1950 subsidence sample points was employed for the model, with 1910 points obtained from the PSInSAR Radar method, and the remaining points derived from leveling measurements. The sample points were split, with 70% allocated to the training set and 30% to the testing set. Following computation and execution, the three models underwent evaluation for accuracy using statistical metrics such as the ROC curve, Area under the curve (AUC), Specificity, Sensitivity, and Overall Accuracy. The research findings revealed that the XGB model exhibited the highest accuracy, achieving an AUC above 0.9 for both the training and test sets. Consequently, XGB was chosen to construct a land subsidence susceptibility map for the Ca Mau peninsula.

The Potential Impact of Rising Sea Levels and Subsidence on Coastal Flooding Along the Northern Coast of Saint-Louis, Senegal

“…What's more, given its amphibious character marked above all by the presence of the river in a context of gradual return of rains in the Sahel [60][61][62], the risk of fluvial overflow exacerbated by soil subsidence and a rise in the river's water level induced by the gradual return of rains is obvious. The same observation is made by [63,64], who show that the city of Ho Chi Minh in Vietnam is subject to fluvial flooding due to the subsidence of the topography and the increased flow of the Saigon River.Our results are in line with those produced by [65,66], in the Mekong delta in Vietnam, in Spain in the Seville river by [67] ; [68] in Poland in the Chechło river; [69] in Hungary and [44] in the Ganges-Brahmaputra-Meghna delta and [70] in the Fraser River delta. Today, many factors are indexed by the scientific community as being the cause of subsidence.…”