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1

Identifying Landslides Prone-Areas Using GIS-based Fuzzy Analytical Hierarchy Process Model in Ziz Upper Watershed (Morocco)

Sadiki Mohamed, Manaouch Mohamed, Aghad Mohamed, Batchi Mouhcine, Al Karkouri Jamal

Ecological Engineering & Environmental Technology

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2023

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Vol. 24, iss. 1

67--83

EN

Landslides cause massive damage to human lives, infrastructure, and property in many regions of the world. These disasters arise on unstable slopes in mountainous regions. The recent increase in these incidents in many regions, including Morocco, has attracted more attention to their study. In this paper, a combination of GIS techniques, fuzzy analytical hierarchy process (FAHP) were integrated to model landslide susceptibility in the upper Ziz catchment, south-eastern Morocco. The data used for this purpose included several geo-environmental and climatic factors affecting susceptibility to landslides. The results of this modeling showed that 16.7% of the studied area has a high susceptibility to landslides, and that the upstream western part is considered the most susceptible. Evaluation of the resulting map’s accuracy using the inventory of 148 landslide events showed that the FAHP model has an important performance, as the value of the area under the curve was about 0.885.

2

Analyzing landslide susceptibility, health vulnerability and risk using multi criteria decision-making analysis in Arunachal Pradesh, India

Rehman Sufa, Azhoni Adani

Acta Geophysica

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2023

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Vol. 71, no. 1

101--128

EN

Landslides being a widespread disaster are associated with susceptibility, vulnerability and risk. The physical factors inducing landslides are relatively well-known. However, how landslide susceptibility will be exacerbated by climate change, impede the attainment of the sustainable development goals and increase health vulnerability is relatively less explored. We present an integrated assessment of landslide susceptibility, health vulnerability and overall risk to understand these interconnected dimensions using Arunachal Pradesh, India, as a case study, which is susceptible to landslides due to its topography and climate conditions. Landslide susceptibility was examined using twenty landslide conditioning parameters through the fuzzy analytical hierarchy process (FAHP). The susceptibility map was validated using the area under the ROC curve (AUC). National Family Health Survey (NFHS 4) data were used to analyze the health vulnerability, while the overall risk was computed through the integration of susceptibility and vulnerability. Landslide susceptibility analysis indicated that nearly 22% area of the state is characterized by moderate susceptibility followed by high (17%) and very high susceptibility (13%). High elevation, slope, rainfall, SPI, drainage density and complex geology were identified as the causative factors of landslides. In the case of health vulnerability, East Kameng and Lohit districts were found to be very highly vulnerable, while Papum Pare, Changlang and Tirap districts experience high health vulnerability due to high degree of exposure and sensitivity. Overall risk analysis revealed over 16.8% area of the state is under moderate risk followed by high (9.8%) and very high (4.2%) risk. Linking this analysis with the climate change projections and SDG goals attainment revealed that Papum Pare, Upper Subansiri, Tirap and West Kameng require priority for lessening susceptibility, vulnerability and risk for achieving sustainable development. A strong correlation (99%) between HVI and risk further demonstrates the need for lessening health vulnerability and risk in the study area. Furthermore, our study contributes additional insights into landslide susceptibility by considering heal vulnerability and risk which may help in planning sustainable development strategies in a changing climate.

3

Podatność osuwiskowa obszaru Krakowa

Kamieniarz Sylwester

Przegląd Geologiczny

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2022

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Vol. 70, nr 9

701--712

EN

Due to the differentiation of landslides in Kraków city area, an artificial neural network method (multilayer perceptron) was used to determine the landslide susceptibility (LS). The calculations were performed in the r.landslide module. The network learning was carried out on the basis of 8 thematic layers (slopes, slope exposure, absolute height, relative height, convergence index, surface lithology, sub-Quaternary lithology, distance from tectonic discontinuities). For modelling, 434 points representing landslides and the same number of points of locations without landslides were used. Among the set of points, 70% was allocated to the training phase, 15% to the validation phase, and 15% to the phase. In order to assess the network performance, based on the results of the test phase, a confusion matrix was made. Approximately 22% of the city’s area is susceptible to landslide occurrence (LS > 0.05 ). It overlap existing landslides and cover areas where they have not occurred yet. The greatest number of areas susceptible to landslide occurrence is located in districts X (54% of the district area) and VII (47%). There are also the most susceptile areas (LS > 0.95). The sensitivity analysis implemented in the module showed that among the thematic layers used for modelling the slopes, convergence index, distance from tectonic discontinuities and sub-Quaternary lithology have the greatest impact on the landslide susceptibility.

4

Changes in the physico-chemical properties of topsoil in a landslide-affected area (western part of the Transylvanian Basin, Romania)

Bălc Ramona, Roba Carmen, Rosian Gheorghe, Costin Dan, Horvath Csaba, Zglobiu Octavia Raluca, Chirtos Diana

Geological Quarterly

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2020

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Vol. 64, No. 4

931--941

EN

Landslides determine increases and decreases in specific soil compounds which is affecting soil fertility. The recovery of soil fertility is a long process and may be used as an indicator of the landslide age and can contribute to the management plan of the affected area. In order to add to data about soil properties affected by landslides, the current study focuses on a young and shallow landslide from the western part of the Transylvanian Depression. Soil samples were analysed from a physico-chemical point of view (pH, organic matter - OM, total organic carbon - TOC, major cations, and iron content) in two places, at between 0 and 60 cm depth (inside and outside the landslide). The results obtained showed lower values of pH inside the landslide, low values of TOC and rock fragments in both places studied (inside and outside the landslide) and no differences in soil texture between disturbed and undisturbed soil. The ammonium, magnesium and calcium content was higher outside the landslide, the sodium level was slightly higher outside the landslide, while the potassium concentration was higher inside the landslide. This study offers new data regarding recovery of soil fertility and highlights the importance of gaining knowledge on soil properties of relevance to future measures to increase the fertility of agricultural soils.

5

Podatność osuwiskowa Polski

Wojciechowski Tomasz

Przegląd Geologiczny

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2019

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Vol. 67, nr 5

320--325

EN

Using the location data of landslides and information on geo-environmental conditions, the landslide susceptibility in Poland was calculated using statistical methods. It shows that 15% of the country’s area is susceptible to landslides. The greatest threats occur in the Carpathians and in many regions of the Sudetes, uplands and in the riverbanks. The most vulnerable areas are the slopes in the range of 9-30°, which are built by the flysch sediments in the faulted zones. The areas susceptible to landslides include over a million buildings and about 7,000 km of roads.

6

Geological and Geomorphological Factors of Natural Hazards in Ukrainian Carpathians

Ivanik Olena, Shevchuk Viktor, Kravchenko Dmytro, Shpyrko Serge, Yanchenko Vitalii, Gadiatska Kateryna

Journal of Ecological Engineering

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2019

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Vol. 20, nr 4

177--186

EN

The consideration was given to the geological and geomorphological factors of natural hazards in the Ukrainian Carpathians. Principal impact of rock lithology, geomorphological structure, underwater regime and seismic processes on the erosion, gravitational and water-gravitational processes formation was demonstrated. The research confirmed a special role of the tectonic factor and the presence of weak zones in the development of natural hazards. Weak zones are characterized by fracturing, brecciation, bedding of flysch deposits and contrast in permeability. The strength properties of rocks decrease drastically within such zones, and large-scale landslide formation processes occur, especially in the case of subparallel location of zones, relative to river valleys and slopes. The factors of hazardous geological processes were defined and classified using GIS analysis and the developed geological model. A conceptual model of landslide hazards in the area of Carpathian Mountains was developed. Weight coefficients of potentially landslide prone factors were determined from the on-site observations and archive data. An integral spatial map of landslide susceptibility was proposed. The results of this research were the basis of geological environment modeling for the assessment of hazardous geological processes impact on the functioning of infrastructure objects.

7

Use of slope failures inventory and climatic data for landslide susceptibility, vulnerability, and risk mapping in souk Ahras region

El Mekki A., Hadji R., Chemseddine F.

Mining Science

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2017

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Vol. 24

237--249

EN

Slope failures (SF) in mountainous terrain often occur during or after heavy rainstorms, resulting in the loss of life and damage to the natural and/or built environment. Assessing areas susceptible to SF is essential for land use planning in threatened areas. This article presents an didactic basedanalysis of the potential contribution to geo-spatial approaches for predicting SF qualitative exposure in mountainous environment. Its main aim is to assess the impact of the geologic, geomorphic, rainstorms, and anthropogenic factors in the initiation of SF in Zaarouria region. 219 events (1996–2016) were inventoried through images interpretation and field surveys and were compared to the physical parameters of the terrain to give a SF susceptibility index value using a simplified model. Vulnerability and risk maps are also established. The Standard deviation classification was used to delineate various susceptibility, vulnerability and risk zones, namely, nil, low, moderate and high. Field data on SF were employed to evaluate and validate the susceptibility zonation map. The results of this study demonstrate that SF are largely governed not only by geoenvironmental conditions but also by human activities, mainly roads and construction.

8

GIS-based technic for roadside-slope stability assessment: an bivariate approach for A1 East-West highway, North Algeria

Dahoua L., Yakovitch S. V., Hadji R. H.

Mining Science

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2017

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Vol. 24

117--127

EN

This paper presents a GIS-based method for landslide susceptibility (LS) assessment using slope-movement inventory and field data. The study has been carried out along A1-Highway (A1-H) in Hanif region as this road section is threated by several types of mass wasting. This hilly zone is known by their landslides sensitive terrains in the North of Algeria. The terrain data are collected from a Géologic map, satellite imageries, digital elevation model, rainfall data, field suveys and ancillary data. In this paper Frequency Ratios (FR) based on bivariate statistical method are evaluated by comparing the observed landslides to their controlling factors. The product of the linear summation of the FR values was a landslide susceptibility index (LSI) map. It was categorized using the natural breaks classification method. The resultant LS zonation map delineates the area into five hierarchic zones. The results confirms that the angle of the slope, plays the most role in wasting especially in road sides. The LS can be used for preliminary land use planning and hazard mitigation purpose. By means of this map the current route of the A1-H can be improved to cross less susceptibles zones.

9

Modelowanie podatności osuwiskowej z zastosowaniem metody indeksowej i wysokorozdzielczych danych z lotniczego skaningu laserowego (LIDAR) na obszarze Gdańska

Małka A.

Przegląd Geologiczny

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2015

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Vol. 63, nr 5

301--311

EN

The paper presents a statistical approach to landslide susceptibility modelling using the GIS-based spatial data analysis. The area of investigation is an urban district in which the activation of mass movements is of interest to both the local population and the authorities. The analyzes were carried out on the basis of the “Map of landslides and risk areas for the city of Gdansk” drawn in 2011. The research took into account the geological, geomorphological, hydrological, hydrogeological and anthropogenic conditions. Eleven landslide influencing factors were considered in the analyses. The landslide susceptibility map was evaluated by the landslides index method. The obtained results show that the most susceptible to landslides are slopes of angle between 10–29° and areas located at a distance of 50 m from watercourses and reservoirs. The presence of silty sands, silts and clays along a lithological layer and the N, NWand NE aspect of a slope are also of great significance. The final map presents the areas with the greatest probability of mass movement occurrence.

10

Zagrożenie i ryzyko osuwiskowe w rejonie Szymbarku (Beskid Niski)

Mrozek T.

Prace Państwowego Instytutu Geologicznego

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2013

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T. 199

1--45

PL

W pracy przedstawiono ilościową ocenę zagrożenia osuwiskowego i związanego z nim ryzyka w testowym rejonie Karpat fliszowych (okolice Szymbarku w Beskidzie Niskim). Wykorzystano równanie Varnesa i schemat metodyczny, pokazujący etapy takiej oceny: od inwentaryzacji osuwisk, przez wyznaczenie podatności na osuwanie i zagrożenia, aż po oszacowanie ryzyka na badanym obszarze. W ten sposób po raz pierwszy w polskiej literaturze dokonano oceny ryzyka osuwiskowego w sposób kompleksowy. Do wyznaczenia podatności na osuwanie i zagrożenia wykorzystano techniki GIS i metodę ELR (Empirical Likelihood Ratio) należącą do klasy funkcji sprzyjania (Favouribility Function). Przeprowadzone modelowanie wykazało przydatność zastosowanych metod do przewidywania zagrożeń w skali obszaru badań (modelowanie w dużej skali – 1:10 0000). Wrażliwość (vulnerability) oszacowano na podstawie wskaźnika odnoszącego koszt napraw do kosztów odtworzenia obiektu. Z kompilacji map zagrożenia i potencjalnych strat powstała mapa ryzyka osuwiskowego dla obszaru badań. Przeprowadzona analiza strat i korzyści w przypadku zagrożenia osuwiskowego wykazała duży (nawet 20%) udział strat pośrednich w stosunku do strat bezpośrednich. Wynika z tego, że straty pośrednie nie mogą być pomijane przy oszacowaniu ryzyka osuwiskowego i powinny by uwzględniane w planowaniu przestrzennym.

EN

The paper presents quantitative estimation of landslide hazard and risk in the test area located in the Polish Flysch Carpathians (surrounding of Szymbark, Beskid Niski Mts.). The adopted approach is enrooted in Varnes equation and, thus, problem solving is tackled with a stepwise strategy comprising landslide inventory, susceptibility and hazard modelling, and assessment of related risk in the studied area. Under such framework the landslide risk has been evaluated comprehensively for the first time in Poland. Drawing upon GIS capabilities, landslide susceptibility and hazard were modelled using ELR (Empirical Likelihood Ratio) function, belonging to Favourability Functions. The performed multivariate statistical modelling turned to be useful for predicting landslide hazard in the test area (large scale modelling - i.e. 1:10 000). Vulnerability was estimated by relating costs of repairs to costs of analysed objects at risk. The developed landslide risk map is the outcome of compiling the landslide hazard map with the map of potential losses. Moreover, the performed cost-benefit analysis showed that indirect losses are significant (up to 20%) when compared to direct ones. Therefore, the indirect losses may not be neglected and have to be taken under consideration in spatial planning and landscape management.

11

A GIS model for integrating temporal ground surface change with potential slope instability using eo : a case study from the Caramanico area, Abruzzo, Italy

Gostelow P., Casarano D., Wasowski J.

Polish Geological Institute Special Papers

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2005

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Vol. 20

46--58

EN

This paper describes a new methodology for assessing landslide susceptibility from temporal land-use change using integrated earth observation (EO) and a GIS. Ground surface change data using LANDSAT and INSAR (permanent scatterer, PS) are used in a physically based geotechnical model which firstly defines initial susceptibility to landslides through geological and geomorphological background data or field study. Secondly it provides the impacts of change in terms of positive or negative effects on limit equilibrium factors of safety (FS) and thirdly the potential outcome of changes at a FS of 1.0 in terms of slope deformation. Application of the model in the Caramanico area using EO data from 1987 to 2000 is described and interpretative and image processing procedural difficulties are discussed. In this study only surface changes from vegetation to artificial structures could be reliably used in the model. Nevertheless preliminary results show promise, suggesting there may be some spatial relationships between areas of historic surface change and deformation recorded by GPS and PS in the urban area.

PL

W artykule przedstawiono nową metodę oceny podatności osuwisk na okresowe zmiany użytkowania terenu. W badaniach wykorzystano zintegrowane obserwacje satelitarne oraz technikę GIS. Na podstawie informacji o zmianach powierzchni Ziemi, uzyskanych z satelitów LANDSAT i INSAR, opracowano model geotechniczny, który, po pierwsze, na podstawie danych geologicznych i geomorfologicznych lub też bezpośrednich badań terenowych, określa podatność terenu na powstawanie osuwisk, po drugie, wskazuje wpływ zmian na granice równowagi czynników bezpieczeństwa (FS), a po trzecie, przedstawia potencjalny efekt zmian na deformację zboczy przy współczynniku FS = 1.0. Opisano też wykorzystanie tego modelu w rejonie Caramanico (Włochy) z uwzględnieniem obserwacji satelitarnych z lat 1987-2000. Przedyskutowano trudności pojawiające się w trakcie obróbki danych satelitarnych i podczas ich interpretacji. Okazało się, że w opracowaniu dotyczącym rejonu Caramanico można wykorzystać jedynie dane dotyczące zmian powierzchniowych, związanych z zamianą terenów pokrytych roślinnością na tereny zabudowane. Niemniej, wstępne wyniki wspomnianych badań sugerują, że mogą istnieć przestrzenne związki istniejących uprzednio zmian powierzchni z deformacjami obszarów zurbanizowanych, odnotowanymi przez pomiary GPS oraz przez satelitarne pomiary radarowe PS.

12

Landslide exposure assessment under environmental change in the Romanian Subcarpathians

Jurchescu Marta, Kucsicsa Gheorghe, Micu Mihai, Sima Mihaela, Bălteanu Dan

Studia Geomorphologica Carpatho-Balcanica

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2019/2020

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Vol. 53/54

59--84

EN

This study focuses on one of the most complex petrographic and structural relief units in Romania, affected by significant earthquakes and uplift neotectonic movements, i.e. the Subcarpathian region. The Subcarpathians represent a highly fragmented hilly area subject to various mass movements and erosion processes, frequently affecting settlements, transport infrastructure and environmental values. The paper aims to present a landslide exposure assessment conducted for this region, following three main stages which are addressed in the context of present environmental conditions and their possible future changes: landslide susceptibility, landslide hazard and the exposure of elements at risk. It also intends to address and discuss the associated specific contexts, problems and challenges. By integrating selected landslide hazard scenarios, computed under different precipitation and seismic conditions, and key data on elements at risk (i.e. built-up areas, arable lands, permanent crops and major protected areas) into GIS spatial and statistical analyses, potential current and future landslide risk areas are outlined. Results are quantified at the Local Administrative Unit (LAU; towns and communes) level. The output maps reveal significant regional differences in landslide susceptibility and hazard according to the specific predisposing and triggering factors considered, as well as spatial variations in the landslide exposure in relation to specific land-uses and protected areas in the region. The present study contributes to increasing knowledge on landslide susceptibility, hazard, and exposure in the area and provides a ground for further related investigations. In addition, because of its predictive character, this study may constitute a useful tool for policy makers supporting decisions with regard to where future priorities should be focused.