Based on GPS and InSAR data, it is known that there is land subsidence in the Bandung Basin of 1.1 - 16.9 cm/year (GPS) and 0.9 - 1.7 cm/year (InSAR). Several types of land subsidence can be expected to occur in the Bandung Basin. However, the detailed characteristics and exact mechanism of land subsidence from a geological perspective in the Bandung Basin are still unknown. Two factors that can cause land subsidence are groundwater extraction and natural consolidation. It is known that there has been a significant decrease in groundwater levels in Bandung since the 1970s due to the very high intensity of groundwater extraction. It is also known that the Bandung Basin comprises one of them, the Kosambi Formation, which consists of organic clays with very high compressibility and undergoes a natural consolidation. Based on these facts, we determine the distribution of land subsidence rates due to groundwater extraction and natural consolidation, along with the percentage of their respective contributions in the Bandung Basin. Research materials include groundwater level depth data and organic clay consolidation data from previous studies. The results showed that the average land subsidence rate due to groundwater extraction was 1.85 cm/year, with a contribution percentage of 44.30%. In comparison, the average land subsidence rate due to natural consolidation was 0.92 cm/year, with a contribution percentage of 15.76%.

Earthquakes and rainfall can trigger landslides in many regions of Indonesia. Rock slopes of andesite outcrops in Gunung Batu and Graha Puspa areas coincide with the Lembang active fault zone in West Java. The region is also subjected to high-intensity rainfall. Thus, the rock slopes are prone to failure during earthquake shaking and heavy rainfall. To mitigate the hazards associated with slope failure in residential areas close to the rock slopes, it is necessary to assess the slope failure hazard at the andesite hill slopes. The study presented in this paper aims to analyse the stability of the andesite slopes using the pseudostatic limit equilibrium method and evaluate the effect of variations of regional seismicity and water content on the stability of the slopes. Pseudostatic analysis considered the peak ground acceleration (PGA) and the calculated horizontal seismic coefficient (kh). The limit equilibrium method was focused on toppling and wedge failure cases. Based on the analysis, the andesite slopes in Gunung Batu and Graha Puspa are stable (FoS ≥ 1.1) in factual conditions (dry-static). In contrast, all slopes have the lowest FoS values (less stable-unstable) under the saturated-pseudostatic conditions. The threshold values of kh and %w (percent water fill) for the slopes’ instability were obtained by varying the regional seismicity and water content conditions. It is recommended that numerical slope stability modeling (i.e., finite element method) be conducted to improve the accuracy of the models.

Earthquake-induced landslides represent a critical threat to transportation infrastructure in tectonically active mountainous regions, particularly in tropical volcanic settings where weak, highly weathered geomaterials dominate. This study develops an integrated framework that directly links physically based seismic threshold modelling with real-time landslide monitoring and operational early warning. The approach is demonstrated in the Cugenang area of Cianjur Regency, West Java, Indonesia, which was severely impacted by the moment magnitude (Mw) 5.6 earthquake in 2022. Slopes composed of highly weathered pyroclastic deposits [Plasticity Index (PI) = 54–68%; porosity > 60%] exhibit low shear strength and high sensitivity to seismic loading. Limit equilibrium analysis using the Morgenstern–Price method that combines the influence of seismic loading and groundwater conditions suggests that a horizontal seismic coefficient (kh) of approximately 0.06, corresponding to a Peak Ground Acceleration (PGA) of about 0.12 gravitational acceleration (g), is a critical threshold for initial landsliding. This comparatively low threshold challenges commonly reported values and demonstrates that slope failure in tropical volcanic terrains can occur under moderate ground shaking, reinforcing the need for site-specific hazard characterisation. The derived thresholds are operationalised within a multi-sensor early warning system integrating Micro-Electro-Mechanical Systems (MEMS) accelerometers and inclinometer measurements. Three hazard levels—Normal (<0.06 g), Alert (0.06–0.12 g), and Emergency (≥0.12 g)are combined with deformation thresholds [30 mm] to capture progressive failure processes and minimise false alarms. By coupling geotechnical modelling and real-time monitoring, this study provides a transferable and scalable framework for enhancing infrastructure resilience in landslide-prone regions.

Based on GPS and InSAR data, it is known that there is land subsidence in the Bandung Basin of 1.1 - 16.9 cm/year (GPS) and 0.9 - 1.7 cm/year (InSAR). Several types of land subsidence can be expected to occur in the Bandung Basin. However, the detailed characteristics and exact mechanism of land subsidence from a geological perspective in the Bandung Basin are still unknown. Two factors that can cause land subsidence are groundwater extraction and natural consolidation. It is known that there has been a significant decrease in groundwater levels in Bandung since the 1970s due to the very high intensity of groundwater extraction. It is also known that the Bandung Basin comprises one of them, the Kosambi Formation, which consists of organic clays with very high compressibility and undergoes a natural consolidation. Based on these facts, we determine the distribution of land subsidence rates due to groundwater extraction and natural consolidation, along with the percentage of their respective contributions in the Bandung Basin. Research materials include groundwater level depth data and organic clay consolidation data from previous studies. The results showed that the average land subsidence rate due to groundwater extraction was 1.85 cm/year, with a contribution percentage of 44.30%. In comparison, the average land subsidence rate due to natural consolidation was 0.92 cm/year, with a contribution percentage of 15.76%.

Based on GPS and InSAR data, it is known that there is land subsidence in the Bandung Basin of 1.1 - 16.9 cm/year (GPS) and 0.9 - 1.7 cm/year (InSAR). Several types of land subsidence can be expected to occur in the Bandung Basin. However, the detailed characteristics and exact mechanism of land subsidence from a geological perspective in the Bandung Basin are still unknown. Two factors that can cause land subsidence are groundwater extraction and natural consolidation. It is known that there has been a significant decrease in groundwater levels in Bandung since the 1970s due to the very high intensity of groundwater extraction. It is also known that the Bandung Basin comprises one of them, the Kosambi Formation, which consists of organic clays with very high compressibility and undergoes a natural consolidation. Based on these facts, we determine the distribution of land subsidence rates due to groundwater extraction and natural consolidation, along with the percentage of their respective contributions in the Bandung Basin. Research materials include groundwater level depth data and organic clay consolidation data from previous studies. The results showed that the average land subsidence rate due to groundwater extraction was 1.85 cm/year, with a contribution percentage of 44.30%. In comparison, the average land subsidence rate due to natural consolidation was 0.92 cm/year, with a contribution percentage of 15.76%.

Landslides pose a significant natural hazard requiring cost-effective, sustainable mitigation strategies. Nature-based solutions utilizing vetiver (Chrysopogon zizanioides) demonstrate considerable potential due to its deep, dense root system, which enhances soil reinforcement. This study examines the effects of growth medium composition and NPK fertilization on the root mechanical properties, biomass accumulation, and vegetative growth of vetiver under controlled greenhouse conditions. The planting medium comprised landslide-affected soil mixed with compost in varying proportions, combined with different NPK fertilizer levels. Root tensile strength was measured to assess mechanical performance, while biomass and vegetative parameters were evaluated to determine growth responses. Results indicate that both growth medium composition and fertilization significantly influence biomass production, root diameter, and tensile strength. The highest biomass (178.33 g) was recorded under T80P20N7.5, while the greatest root diameter (1.47 mm) and tensile strength (21.9 MPa) were observed under T100P0N0. These outcomes suggest a trade-off between biomass production and mechanical reinforcement. Overall, optimizing soil amendments and nutrient inputs enhances vetiver’s bio-reinforcement capacity, supporting its application in sustainable slope stabilization and landslide mitigation.