Natural Terrain Landslide Risk Mitigation

Dominica is a geologically young, volcanic island in the eastern Caribbean. Due to its rugged terrain, substantial rainfall, and distinct soil characteristics, it is highly vulnerable to landslides. The dominant triggers of these landslides are hurricanes, tropical storms, and heavy prolonged rainfall events. These events frequently lead to loss of life and the need for a growing portion of the island’s annual budget to cover the considerable cost of reconstruction and recovery. For disaster risk mitigation and landslide risk assessment, landslide inventory and susceptibility maps are essential. Landslide inventory maps record existing landslides and include details on their type, location, spatial extent, and time of occurrence. These data are integrated (when possible) with the landslide trigger and pre-failure slope conditions to generate or validate a susceptibility map. The susceptibility map is used to identify the level of potential landslide risk (low, moderate, or high). In Dominica, these maps are produced using optical satellite and aerial images, digital elevation models, and historic landslide inventory data. This study illustrates the benefits of using satellite Interferometric Synthetic Aperture Radar (InSAR) to refine these maps. Our study shows that when using continuous high-resolution InSAR data, active slopes can be identified and monitored. This information can be used to highlight areas most at risk (for use in validating and updating the susceptibility map), and can constrain the time of occurrence of when the landslide was initiated (for use in landslide inventory mapping). Our study shows that InSAR can be used to assist in the investigation of pre-failure slope conditions. For instance, our initial findings suggest there is more land motion prior to failure on clay soils with gentler slopes than on those with steeper slopes. A greater understanding of pre-failure slope conditions will support the generation of a more dependable susceptibility map. Our study also discusses the integration of InSAR deformation-rate maps and time-series analysis with rainfall data in support of the development of rainfall thresholds for different terrains. The information provided by InSAR can enhance inventory and susceptibility mapping, which will better assist with the island’s current disaster mitigation and resiliency efforts.

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Landslide Characteristics and Evolution: What We Can Learn from Three Adjacent Landslides

Remote Sensing ◽

10.3390/rs13224579 ◽

2021 ◽

Vol 13 (22) ◽

pp. 4579

Author(s):

Dongdong Yang ◽

Haijun Qiu ◽

Yaru Zhu ◽

Zijing Liu ◽

Yanqian Pei ◽

...

Keyword(s):

Time Series ◽

Risk Mitigation ◽

Landslide Risk ◽

Significant Heterogeneity ◽

Interferometric Synthetic Aperture Radar ◽

Antecedent Precipitation ◽

Surface Time ◽

Field Investigations ◽

Landslide Processes ◽

Slow Moving

Landslide processes are a consequence of the interactions between their triggers and the surrounding environment. Understanding the differences in landslide movement processes and characteristics can provide new insights for landslide prevention and mitigation. Three adjacent landslides characterized by different movement processes were triggered from August to September in 2018 in Hualong County, China. A combination of surface and subsurface characteristics illustrated that Xiongwa (XW) landslides 1 and 2 have deformed several times and exhibit significant heterogeneity, whereas the Xiashitang (XST) landslide is a typical retrogressive landslide, and its material has moved downslope along a shear surface. Time-series Interferometric Synthetic Aperture Radar (InSAR) and Differential InSAR (DInSAR) techniques were used to detect the displacement processes of these three landslides. The pre-failure displacement signals of a slow-moving landslide (the XST landslide) can be clearly revealed by using time-series InSAR. However, these sudden landslides, which are a typical catastrophic natural hazard across the globe, are easily ignored by time-series InSAR. We confirmed that effective antecedent precipitation played an important role in the three landslides’ occurrence. The deformation of an existing landslide itself can also trigger new adjacent landslides in this study. These findings indicate that landslide early warnings are still a challenge since landslide processes and mechanisms are complicated. We need to learn to live with natural disasters, and more relevant detection and field investigations should be conducted for landslide risk mitigation.

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Towards A Geo-Hydro-Mechanical Characterization of Landslide Classes: Preliminary Results

Applied Sciences ◽

10.3390/app10227960 ◽

2020 ◽

Vol 10 (22) ◽

pp. 7960

Author(s):

Federica Cotecchia ◽

Francesca Santaloia ◽

Vito Tagarelli

Keyword(s):

Risk Mitigation ◽

Mitigation Strategies ◽

Slope Instability ◽

Mitigation Measures ◽

Economic Losses ◽

Landslide Risk ◽

Multidisciplinary Analysis ◽

Risk Mitigation Strategies ◽

Landslide Mechanisms

Nowadays, landslides still cause both deaths and heavy economic losses around the world, despite the development of risk mitigation measures, which are often not effective; this is mainly due to the lack of proper analyses of landslide mechanisms. As such, in order to achieve a decisive advancement for sustainable landslide risk management, our knowledge of the processes that generate landslide phenomena has to be broadened. This is possible only through a multidisciplinary analysis that covers the complexity of landslide mechanisms that is a fundamental part of the design of the mitigation measure. As such, this contribution applies the “stage-wise” methodology, which allows for geo-hydro-mechanical (GHM) interpretations of landslide processes, highlighting the importance of the synergy between geological-geomorphological analysis and hydro-mechanical modeling of the slope processes for successful interpretations of slope instability, the identification of the causes and the prediction of the evolution of the process over time. Two case studies are reported, showing how to apply GHM analyses of landslide mechanisms. After presenting the background methodology, this contribution proposes a research project aimed at the GHM characterization of landslides, soliciting the support of engineers in the selection of the most sustainable and effective mitigation strategies for different classes of landslides. This proposal is made on the assumption that only GHM classification of landslides can provide engineers with guidelines about instability processes which would be useful for the implementation of sustainable and effective landslide risk mitigation strategies.

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Application of FLaIR model for early warning system in Chibo Pashyor, Kalimpong, India for rainfall-induced landslides

10.5194/nhess-2017-295 ◽

2017 ◽

Cited By ~ 2

Author(s):

Abhirup Dikshit ◽

Neelima Satyam

Keyword(s):

Early Warning ◽

Early Warning System ◽

Risk Mitigation ◽

Warning System ◽

Landslide Risk ◽

Rainfall Forecasting ◽

Landslide Occurrence ◽

Mobility Function ◽

Hourly Rainfall ◽

Rainfall Model

Abstract. The development of an early warning system for landslides due to rainfall has become an indispensable part for landslide risk mitigation. This paper explains the application of the hydrological FLaIR (Forecasting of Landslides Induced by Rainfall) model, correlating rainfall amount and landslide events. The FLaIR model comprises of two modules: RL (Rainfall-Landslide) which correlates rainfall and landslide occurrence and RF (Rainfall-Forecasting) which allows simulation of future rainfall events. The model can predetermine landslides based on identification of mobility function Y(.) which links actual rainfall and incidence of landslide occurrence. The critical value of mobility function was analyzed using 1st July 2015 event and applying it to 2016 monsoon to validate the results. These rainfall thresholds presented can be improved with intense hourly rainfall and landslide inventory data. This paper describes the details of the model and its performance for the study area.

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Assessment of landslide susceptibility for civil protection purposes by means of GIS and statistical analysis: lessons from the Province of Modena, Italy

Revista de Geomorfologie ◽

10.21094/rg.2017.009 ◽

2017 ◽

Vol 19 (1) ◽

pp. 29-43

Author(s):

LIBERATOSCIOLI Elena ◽

VAN WESTEN Cees J. ◽

SOLDATI Mauro

Keyword(s):

Landslide Susceptibility ◽

Risk Mitigation ◽

Mass Movement ◽

Critical Issue ◽

Weight Of Evidence ◽

Slope Position ◽

Landslide Risk ◽

Civil Protection ◽

Multi Temporal ◽

Position Index

This paper is focused on the analysis of landslide susceptibility for civil protection purposes. A methodology was developed and applied to support measures aiming at landslide risk mitigation. It is based on GIS and the Weight of Evidence (WofE) method, which was preferred among several other statistical approaches because it is suitable for large areas, easy to interpret and simple to program. The latter feature is important for implementing a GIS tool aimed to facilitate Civil Protection in the updating of susceptibility maps. An application of the methodology was performed in a mountainous and hilly area of the Northern Apennines (Italy) located in the Province of Modena where landslides are a critical issue in terms of civil protection due to the recurrent damages to buildings, roads and infrastructures. According to the Region Emilia-Romagna Landslide Inventory Map (RER LIM), shallow slides and earth flows are by far the most widespread mass movement types. Hence, the susceptibility assessment concerned these two types of movements. The choice of the training set, based on active landslides, took into account possible limitations of the input data. The predisposing factors were lithology, slope, curvature, Slope Position Index, aspect, land use, distance from roads. The validation was conducted through the PRC and SRC curves, and direct checking (comparison with past occurrences, multi-temporal orthophotos and field surveys). The resulting models predicted the location of landslides in an acceptable manner. One map for each type of landslides was produced and afterwards they were combined in a single document to improve their intelligibility in a civil protection framework.

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The SafeLand Compendium of Landslide Risk Mitigation Measures

Landslide Science and Practice ◽

10.1007/978-3-642-31319-6_87 ◽

2013 ◽

pp. 683-689 ◽

Cited By ~ 5

Author(s):

Giovanni Vaciago

Keyword(s):

Risk Mitigation ◽

Mitigation Measures ◽

Landslide Risk

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APPLICATION OF AHP METHOD FOR MAPPING SLOPE GEOMORPHIC PHENOMENA

10.31219/osf.io/69xc5 ◽

2017 ◽

Author(s):

Florin Constantin MIHAI

Keyword(s):

Risk Mitigation ◽

Characteristic Curve ◽

Confusion Matrix ◽

Predictive Performance ◽

Landslide Risk ◽

Good Correspondence ◽

Topographic Features ◽

Digital Elevation ◽

Elevation Model ◽

Hierarchy Process

Landslides are common and frequent geomorphic phenomena for the plateau regions in Romania having important consequences, especially economic ones, that needs designing scientific and technical plans for landslide risk mitigation. For this, an important preliminary step is assessing and mapping the landslide susceptibility. This paper examines a plateau zone in eastern Romania providing such a map, based on the landslides inventory, the digital elevation model (DEM) and the thematic layers of several factors thought to be potential predictors of landslides occurrence: topographic features, land use, and lithology. The methodological framework is based on the analytical hierarchy process (AHP) principles and factors weights attributed based on frequency of landslides. The predictive performance of the model was assessed using the confusion matrix, the ROC (receiver operating characteristic) curve and the AUC (area under curve) parameter. The results indicate a good correspondence between the susceptibility estimated for the test samples and for the validation samples

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Methodologies of Economic Measurement and Vulnerability Assessment for Application in Landslide Risk Analysis in a Highway Domain Strip: A Case Study in the Serra Pelada Region (Brazil)

Sustainability ◽

10.3390/su11216130 ◽

2019 ◽

Vol 11 (21) ◽

pp. 6130 ◽

Cited By ~ 1

Author(s):

Ellen Felizardo Batista ◽

Larissa De Brum Passini ◽

Alessander Christopher Morales Kormann

Keyword(s):

Vulnerability Assessment ◽

Risk Mitigation ◽

Indirect Costs ◽

Direct Costs ◽

Mitigation Strategies ◽

Economic Losses ◽

Landslide Risk ◽

Total Cost ◽

Landslide Occurrence ◽

Serra Do Mar

Landslides are one of the main causes of death caused by disasters in the world. In this study, methodologies to measure landslide costs and to assess vulnerability are presented, with the objective of applying them to landslide risk analyses. The methodologies were applied in a region of Serra do Mar, which is crossed by a highway. The analyses and mappings were implemented in a Geographic Information System (GIS). Through the application of the methodology that considers both direct and indirect costs in the composition of total cost, it was established how much an m2 of a landslide would cost. The composition of direct costs encompassed the damages related to restoration or construction of the highways, infrastructures, unpaved roads, residential and commercial buildings, vegetal cover and agricultural areas. In indirect costs, the economic losses by victims, highway interdiction, and agricultural area profitability were calculated. In the methodology for vulnerability assessment, bodily injuries, structural damages, and functional disturbances resulted from landslides were analyzed. The risk assessment was performed through the junction of the maps of total cost, vulnerability and susceptibility. The results indicate that indirect costs were predominant in cost composition, corresponding to 87% of total costs, in comparison to 13% of the direct costs, stressing the importance of considering indirect costs in economic measurement studies. As a result, it is possible to conclude that studying landslide consequences as economic parameters supports the increasing need of performing risk quantitative analyses. It is also prudent to add that these studies help decision makers in projects of disaster risk mitigation strategies, by allowing the identification of regions with greater economic impacts in case of landslide occurrence.

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