Search

Yang, J., 2018. Landslide damage from extreme rainstorm geological accumulation layers within plain river basins. In: Ashraf, M.A. and Chowdhury, A.J.K. (eds.), Coastal Ecosystem Responses to Human and Climatic Changes throughout Asia. To provide the basis of an early warning and detection for landslide disasters and to provide decision support for local governments in disaster prevention and mitigation, this research studied landslide damage assessment from the geological accumulation layer in a plain river basin under conditions of an extreme rainstorm. Based on an analysis of the relationship between landslide geology and rainfall and a damage model of landslides under conditions of extreme rainfall, the landslide damage assessment described in this article used the SINMAP model. The layer of geological accumulation in the Wenchuan–Diexi River section in the upper reaches of the Minjiang River was the study area. Spatial distribution characteristics and the main factors inducing a landslide disaster were studied, and a danger-evaluation model for landslides in that region was established for landslide assessment research and for applying that research. Based on the SINMAP model, the effects of different extreme rainstorm events on the stability of regional slopes were analyzed. The results of a stability evaluation for landslides show that the area has an unstable zone of 4339.8 km2, which accounts for 64.49% of the total area. The unstable area in this evaluation was basically consistent with the distribution of an existing landslide, which shows that the model can adequately evaluate slope stability and landslide potential from the layer of geological accumulation in this area. [ABSTRACT FROM AUTHOR]

Many landslides were triggered by heavy rainfall from 29 June to 1 July 2017 in Ningxiang County, Hunan Province, China. A field investigation into one of the landslides, known as the Wangjiawan landslide, was undertaken on July 3, 2017, to understand the landslide mechanisms and the factors that triggered the event. The landslide is a translational and rotational slide that degraded downslope to an earth flow. It occurred on a steeply dipping mud-rich slate intercalation. Field investigation shows that the landslide had a movement rate of more than 25 m/s and had been triggered by up to 338 mm of continuous rainfall over 2 days. The landslide was fast-moving because it occurred on a steep slope and showed a rapid reduction in shear strength. The landslide resulted in nine fatalities and 19 injuries, most during initial rescue efforts. To mitigate a possible secondary landslide disaster, later emergency measures including evacuation of the survivors, setting up warning signs, and covering landslide cracks with plastic sheeting were adopted. [ABSTRACT FROM AUTHOR]

Landslides are a ubiquitous hazard in terrestrial environments with slopes, incurring human fatalities in urban settlements, along transport corridors and at sites of rural industry. Assessment of landslide risk requires high-quality landslide databases. Recently, global landslide databases have shown the extent to which landslides impact on society and identified areas most at risk. Previous global analysis has focused on rainfall-triggered landslides over short ~5- year observation periods. This paper presents spatiotemporal analysis of a global dataset of fatal non-seismic landslides, covering the period from January 2004 to December 2016. The data show that in total 55 997 people were killed in 4862 distinct landslide events. The spatial distribution of landslides is heterogeneous, with Asia representing the dominant geographical area. There are high levels of interannual variation in the occurrence of landslides. Although more active years coincide with recognised patterns of regional rainfall driven by climate anomalies, climate modes (such as El Niño-Southern Oscillation) cannot yet be related to landsliding, requiring a landslide dataset of 30C years. Our analysis demonstrates that landslide occurrence triggered by human activity is increasing, in particular in relation to construction, illegal mining and hill cutting. This supports notions that human disturbance may be more detrimental to future landslide incidence than climate. [ABSTRACT FROM AUTHOR]

The World Landslide Forum is a triennial mainstream conference that gathers together the scientific and technological community, policymakers, industry actors, public officials, and other stakeholders, who deal with the understanding and management of landslide disaster risk. The establishment of the ISDR-ICL Sendai Partnerships 2015-2025 for Global Promotion of Understanding and Reducing Landslide Disaster Risk in Sendai during the 2015 World Conference on Disaster Risk Reduction (WCDRR) enabled the landslide science and technology community support the implementation of the Sendai Framework for Disaster Risk Reduction 2015-2030 in order to prevent new and reduce existing disaster risk. The 4th World Landslide Forum (WLF4) was held in Ljubljana, Slovenia, from 29 May to 2 June 2017 and discussed the progress of landslide research and risk reduction for advancing the culture of living with natural hazards. A high-level panel composed of United Nations officials, international stakeholders, and national organizations sought to identify the best mechanisms to be developed by the community of the International Consortium on Landslides (ICL). The objective was to advance the implementation of the ISDR-ICL Sendai Partnerships, to achieve a better commitment among partners, and to provide substantive services to developing countries. During the WLF4, the 2017 Ljubljana Declaration on Landslide Risk Reduction was adopted and the concept framework of the Kyoto 2020 Commitment was endorsed. [ABSTRACT FROM AUTHOR]

Landslides are recurrent phenomena in Italy, but little is known regarding the public perception of related risk. In order to investigate landslide risk perception of recent phenomena, we decided to perform a qualitative investigation in Frosinone (Lazio, Central Italy) where, during 2013, a relevant landslide ('Viaduct Biondi') occurred. Survey results highlighted that Frosinone population have been experiencing landslides but do not consider themselves threatened and prepared in occurrence of this type of emergency. This study pointed out that Frosinone municipality and surrounding town populations behave as an inactive actor in land conservation and management, addressing major responsibility to institutions. For this reason, realization of a purposed designed dissemination campaign would be useful in order to improve citizen knowledge and to enhance their participation in landslide risk reduction activities. [ABSTRACT FROM AUTHOR]

Scientific literature is replete with papers describing advances in applying new technologies to the study of landslides and advances in our understanding of factors affecting landslide occurrence, distribution, and movement. Far fewer papers look at how this knowledge is implemented to achieve landslide risk reduction. State and local governments exercise the greatest control on how landslide risk reduction is accomplished. Data generated from a questionnaire to state geological surveys, review of their agency Web sites, and two case studies demonstrate that progress has been made during the last 20 years in implementing actionable policy changes and programs to achieve a reduction is landslide risk in the United States. Progress is evident from the pivotal role played by state and local government in the areas of: (1) developing guidelines and training, (2) increasing public awareness and education, (3) implementing loss reduction measures, and (4) conducting emergency preparedness, response, and recovery. The number of states requiring registration for practicing geologists has nearly doubled during the last 20 years. This increase was accompanied by a shift from individual state tests as part of determining competency to a uniform national test. During this period, state geological surveys established Web sites as a primary means for promoting public awareness and education about landslide hazards. Measures reducing the impact of landslides have included providing information specific to residents and landowners, as well as supporting land-use planning efforts by local governments. Many state geological surveys are involved with emergency management of landslide hazards. [ABSTRACT FROM AUTHOR]

Assessing how many people are exposed and where are they located is a crucial step in landslide risk management and emergency planning. Frequently the available population statistical data have no sufficient detail to an accurate assessment of the potential exposed people to a hazardous phenomenon, mainly if it occurs at the local scale, like landslides. The present study aims to apply the dasymetric cartography technic to improve population spatial resolution and to assess potential exposed population. An additionally objective is to compare the obtained results with a more common approach that uses basic census units in its better spatial resolution (BCU) as spatial units. Considering the Portuguese census data and a layer of residential building limits, whose area was used as ancillary information, the number of exposed inhabitants significantly differs between two approaches. Using BCU approach and considering the three highest landslide susceptible classes, people inhabitants are overestimated in 132 % (2539 inhabitants). Despite the associated uncertainties in a general cost-benefit analysis the presented methodology seems to be a reliable approach as first approximation to a more detailed estimation of exposed people. The approach based on dasymetric cartography allows an increasing of the spatial resolution of population over large areas and enable the use of detailed landslide susceptibility maps and thus improving the population assessment. [ABSTRACT FROM AUTHOR]

European Union directives as well as national legislation are placing great emphasis on the inclusion of stakeholder perspectives in the governance of risks from natural hazards. This should help decision makers formulate better policies. However, to date, there is little information on stakeholders' perspectives with respect to landslide risk governance. This paper addresses the gap by reporting on research in Nocera Inferiore, Italy. The research is based on a documentary analysis, 43 semi-structured interviews and a survey submitted to 373 residents. The political instability, the unfairness of national funding allocation across municipalities and the residents' lack of knowledge about risk assessment and emergency planning are some of the main barriers to effective risk governance. Moreover, there are divergent, sometimes even opposite, stakeholders' views on several issues, such as the relevance of illegal development in risky areas. The results highlight the importance of addressing these divergent views and including the plurality of voices as a prerequisite for inclusive risk governance. The research provided essential background information for a participatory process, which was designed to support decisions on landslide risk mitigation measures in Nocera Inferiore (Linnerooth-Bayer et al. this issue). The methodology will be of more general interest to researchers and policymakers intent upon including stakeholder perspectives in natural risk governance. [ABSTRACT FROM AUTHOR]

Landslide susceptibility mapping is an important tool for disaster management and development activities such as planning of transportation infrastructure, settlement and agriculture. Selelkula area of the Jema River Gorge in Central Ethiopian Highland was chosen as a study area. Fuzzy logic (FL) and rock engineering system (RES) in a GIS environment were employed to prepare landslide susceptibility maps for this area. Data sets including slope, aspect, profile curvature, plan curvature, lithology, land use, distance from river and distance from lineament were generated using the field data, remote sensing and GIS. In FL, the fuzzy membership values were calculated by normalizing the frequency ratio values of each factor's class in a range between 0 and 1. Then, the fuzzy membership values were combined by fuzzy AND, fuzzy OR, fuzzy gamma, fuzzy sum and fuzzy product operators. A total of twelve landslide susceptibility maps were produced using FL and the best map was chosen based on area under the curve (AUC) of the receiver operating characteristic (ROC) curve and the highest difference between minimum and maximum susceptibility index values. Based on these criteria, the landslide susceptibility map produced using fuzzy gamma ( γ = 0.8) operator was selected. RES is a semi-quantitative method which assigns each factor's classes a value between 0 and 4 based on the principles of Hudson (Rock engineering systems, theory and practice. Ellis Horwood, Chichester, ) and uses an interaction matrix through a coding system of five values in previous researches but a coding system of nine values has been used in this study to provide a wider range of values for interactions among each pair of landslide factors and each landslide factor with a landslide. Unlike other methods, RES has a freedom to evaluate and assign each interaction based on expert's knowledge and experience. But it also bears the problem of subjectivity in assigning the interaction values. On the other hand, FL is completely data driven and does not show any subjectivity in assigning values for each factor class. The prediction accuracies of FL and RES, which can be determined from ROC curves, were found to be 87.2 and 88.6 %, respectively. For validation purpose, the existing landslides were overlaid over the two landslide susceptibility maps and the percentage of landslides in each susceptibility class was calculated. The percentages of landslides that fall in the high and very high susceptibility classes are slightly higher in RES than FL method and hence the former is more accurate in predicting the future landslide occurrence than the later. [ABSTRACT FROM AUTHOR]

The Third World Landslide Forum was held on 2-6 June 2014 at the China National Convention Center, Beijing, China. This article outlines the background and the objectives of the World Landslide Forums and reports on the organized sessions and published books for the Third World Landslide Forum. During this triennial event of ICL, World Centres of Excellence on Landslide Risk Reduction and IPL Awards for Success, Varnes Medal, Best paper awards, and others were conferred. Through the examination in the high-level panel discussion on the first day and the roundtable discussion on the final day, 2014 Beijing Declaration 'Landslide Risk Mitigation: Toward a Safer Geo-environment' was adopted. It is a document calling to join the planned Sendai partnerships 2015-2024 as a contribution to post-2015 Framework for Disaster Risk Reduction. [ABSTRACT FROM AUTHOR]

Abstract: Landslide risk is a function of the probability of the event and its consequences. Previous research has shown that preventive measures to reduce the risk are preferred over reactive measures but, especially in developing countries, rarely undertaken. A contributing factor is the lack of evidence that preventive measures pay. This study includes a brief overview of landslide risk management in general and an investigation of the present risk management situation in Sweden based on interviews in 11 municipalities complemented with interviews in Norway. The result shows that climate change has become part of the general awareness and started to be taken into account in the municipal spatial planning. Landslide susceptibility maps and databases are useful tools in the complex spatial planning. The results indicate that the application of landslide susceptibility and risk maps as previously applied for preventive measures and spatial planning in the landslide prone area Göta älv river valley have been cost effective. Improved documentation and more active communication among different stakeholders would, however, contribute to more effective landslide management. [Copyright &y& Elsevier]

This paper concerns a regional scale warning system for landslides that relies on a decisional algorithm based on the comparison between rainfall recordings and statistically defined thresholds. The latter were based on the total amount of rainfall, which was cumulated considering different time intervals: 1-, 2- and 3-day cumulates took into account the critical rainfall influencing shallow movements, whilst a variable time interval cumulate (up to 240 days) was used to consider the triggering of deep-seated landslides in low permeability terrains. A prototypal version of the model was initially set up to define statistical thresholds. Then, thresholds were calibrated using a database of past georegistered and dated landslides. A validation procedure showed that the calibration highly improves the results and therefore the model was integrated in the regional warning system of Emilia Romagna (Italy) for civil protection purposes. The proposed methodology could be easily implemented in other similar regions and countries where a sufficiently organised meteorological network is present. [ABSTRACT FROM AUTHOR]

In this paper, we present a state-of-the-art wireless sensor network (WSN) of deep-earth probes (DEPs) that has been deployed to monitor an active landslide in the Western Ghats mountain range of South India. While India has one of the highest incidences of landslides and landslide-induced fatalities-primarily in the Himalayas of North India and in the Western Ghats of Central and South India-our study is perhaps the first comprehensive attempt to instrumentally detect landslides in the Western Ghats. Wireless networks have enabled us, since June 2009, to continuously monitor the deployment site in real time and from anywhere around the globe. There have been a few earlier landslide monitoring WSNs using accelerometers in Emilia Romagna Apennines, Italy; global navigation satellite system (GNSS) sensors to monitor the Hornbergl landslide, Austria; and vibrating wire stress sensors to monitor a slope in China. We improved upon these WSN systems by incorporating a variety of sensors-piezometers, dielectric moisture sensors, strain gauges, tiltmeters, a geophone, and a weather station-and installing some of these sensors as deep as 20 m below the ground surface. We present the salient aspects of the field deployment of DEPs: the selection of sensors and their incorporation in DEPs, the methodology we used in embedding these DEPs into the soil, and a few of the key aspects of the wireless sensor network. We also present a description of the deployment site and some of the results of geotechnical investigations carried out on borehole corings. Finally, we present the more interesting field data collected from the monitoring system during a rainy season in July and August 2009. [ABSTRACT FROM AUTHOR]

This work evaluates the capability of Web Processing Service (WPS) to foster the shallow landslides hazard awareness. In particular this study demonstrates how the WPS can provide an ideal environment for the development of real-time applications by creating a process chain able to couple two widely used models, TRIGRS and DFWALK, respectively applied for (i) the localization and characterization of areas susceptible to shallow landslides and (ii) the assessment of these landslides run-out in ease of collapse. The service has been built with the PyWPS software by integrating the models through the GIS GRASS. The application, tested for the case study of Ha Giang (Vietnam), can be generally deployed and used both as service for shallow landslide hazard forecast and as a tool for the identification of vulnerable areas for emergency planning design. [ABSTRACT FROM AUTHOR]

The article presents a research paper that aims to minimize losses caused by landslide through enhanced level of understanding and knowledge of the disaster and its management. It explores the basic causes of landslides, the factors that should be considered in landslide management, and the methods used for landslide prevention or control including excavation and fillings, electro-osmosis and evapo-transpiration, and erosion control. It discusses several distinctive features and characteristics of landslide prone areas as well as the three basic principles of Risk Assessment and Vulnerability Analysis. It also examines long-term hazard reduction and emergency management and response as the two components in reducing landslide-associated costs.