Geomorphologic Hazards Research Articles

Risks Associated to Transportation between the Socioeconomic Costs and Territorial Management Strategies: The Case of Kalaa Sraghna in Morocco

The concept of risk has become widely circulated within the academic communities, and the reason behind this interest is the enormity of Losses and their high cost to humans and their properties. Hence, the reasons for studying these risks and searching for effective solutions emerged to reduce the size of its losses. Risks are divided into several types, including geological hazards such as earthquakes and volcanoes and climate risks such as storms, floods and desertification and geomorphologic hazards such as landslides and sedimentation…And environmental hazards such as air and marine pollution…Social risks such as breaking the family’s union and the emergence of social Disorder. This study comes to approach the problem of the risks associated with transportation and its economic and social costs, through the case of the province of Kalaa Sraghna, the transportation system poses three basic risks: The risk of traffic accidents, which leaves hundreds dead and thousands injured. The natural hazards can also make the roads affected by flooding, and the third risk is the problem of both air and sound pollution due to transportation. Geographical research has become required to provide solutions to these problems. In this context, we have presented a set of suggestions to treat and minimize the impact of these risks, for sustainable transport that satisfies the population’s need for mobility and contributes to territorial development.

Tipping Points in Natural Hazard Risk Management: How Societal Transformation can Provoke Policy Strategies in Mitigation

In this paper, we show how the concept of tipping points can be interpreted by using the example of natural hazard management. Until now, despite the increasing amount of papers on tipping points in the assessment of geomorphologic hazards and the associated dynamics of research on climate change, there has been little empirical or theoretical engagement with tipping points in risk management and in the adaptive capacity of individual actors or social systems. By bridging this gap, we focus on adaptation initiatives to mountain hazard management and on the question of how these initiatives were triggered using three different study sites in Austria. Necessary system changes root in different nutshells, such as lack of funding, lack of legal incentives to include local interests or lack of space, where classical structural protection schemes cannot respond to the emerging challenges of system dynamics. This paper used a mixed-method approach, including semi-structured in-depth interviews, scenario constructions and policy analysis to assess the potential tipping points in the implementation of innovative systems to manage mountain hazards. The results showed that vital variables influencing the development of new management measures are (1) the current legislation, (2) risk acceptance among authorities and the public, (3) land-use pressure, (4) the demand for innovative solutions, (5) the available technical standards and possibilities and (6) finally the policy entrepreneurship. Concluding the results, contemporary settings concerning risk management strategies will have to change in the future in order to inspire transformative governance arrangements in natural hazard management.

The Flood Impact Assessment from Ilisua Catchment Area on the Environment

In the first part of the paper are making a geomorphologic description of the catchment area and the flash floods taken into account. All these events show the vulnerability of the catchment area studied to hydro morphological and geomorphologic hazards, fact that draws attention to their management by a new approach, namely of the flood risk management.Flash floods produced in June 2006 in catchment area Ilisua had a rain genesis, with values between 28 l/m2 in the low area, respectively 53 l/m2 in high areas of basin areas. Low surface of the superior catchment area has determined quick concentration of the water toward the main collectors and formation by flood, phenomenon facilitated and by the fragmentation relatively high of relief, thus ensuring a contribution hydrological important. Floods formatted in superior river basin of Ilisua River, have determined in addition by the erosion effect, entrapment and redistribution of a huge volume of silt. At the end of the paper, by applying the current concepts of the effect reduction in impact with environmental, is proposed the series of structural and non-structural measures for reducing flood intensity.

Thermomechanical stress–strain numerical modelling of deglaciation since the Last Glacial Maximum in the Adamello Group (Rhaetian Alps, Italy)

Deglaciated areas in the valleys of the Italian Alps have recently exhibited a high potential for geomorphologic hazards from diffuse deep-seated gravitational deformations (DSGSDs), caused by rock-mass creep processes that can evolve into rock falls and rock avalanches. A multidisciplinary approach that integrated geomorphologic surveys and stress–strain numerical simulations was used to investigate the effects of the stress release that was induced by the Last Glacial Maximum (LGM) in the Adamè Valley (Italian Alps). No evidence of DSGSDs has been found in this area; however, data are available to develop a well-constrained evolutionary model of the valley deglaciation. The extent and thickness of the southern extension of the Adamello glacier (the widest glacier in Italy) during its primary growth phases, including those of the LGM, three Late Glacial stages and the Little Ice Age (LIA) were reconstructed using glacial geological surveys and were reproduced using a finite-difference stress–strain sequential model spanning from the LGM to the present. A thermomechanical numerical configuration was developed based on geomechanical field measurements that were collected from rock outcrops and data from laboratory tests, specifically performed on intact rock samples. The numerical simulations demonstrate that thermomechanical viscous behaviour cannot be neglected because the resulting strains on the slopes are significantly higher than those resulting from conventional elastoplastic behaviour. The last major thermal effect in the rock masses reproduced using the model occurred from 11.5ka until the LIA; the resulting displacement rates are as much as several tens of mm/ka, which are consistent with the absence of DSGSDs in the Adamè Valley, as these rates are significantly lower than those previously obtained from DSGSDs and other large landslides in the Alps. Based on thermomechanical numerical solutions, these rates should persist for the next 1000years assuming that no variations in current climatic conditions occur.

GEOMORPHOLOGIC HAZARDS AND DISASTERS IN THE SOUTH AMERICAN ANDES

GEOMORPHOLOGIC HAZARDS AND DISASTERS IN THE SOUTH AMERICAN ANDES

Documentary proxies and interdisciplinary research on historic geomorphologic hazards: a discussion of the current state from a central European perspective

During the last two decades, documentary data (written and iconographic sources) have been increasingly employed in geomorphologic research aiming at reconstruction of territorial distribution, temporal occurrence and social and economic impacts of various geomorphologic hazards. The goal of this paper is to broaden the previous discussion (Glade et al. The use of historical data in natural hazard assessments. Kluwer, Dordrecht, 2001) of the methodological constraints on the use of documentary data for geomorphologic hazard research. Using the interdisciplinary approach of geomorphology, historiography and medial studies, we firstly summarise the major finding of papers that have employed various types of documentary data sources to study geomorphologic hazards in different regions. In the second section, we present case studies from the Czech Republic resulting from the ongoing research project that is devoted to the assessment of the potential of documentary data to reconstruct past occurrences of and mitigation strategies for geomorphologic hazards. Finally, we discuss three main methodological issues emerging from our research: (a) problems emerging from the positivist approach to documentary data sources and the necessity for critical analyses of documentary data sources based on modern historiographic approaches, (b) constraints arising from the combination of documentary data from different spatiotemporal scales and (c) lacks in the use of documentary data to study local-based adaptation strategies to cope with geomorphologic hazards.

Ensuring Human Safety in the Disaster Prone Coastal Town of Limbe, Cameroon

Limbe in Fako Division of the South West region of Cameroon is located in an active and dynamic coastal zone characterized by geological, geophysical, geomorphologic and climatic hazards. This paper examines the nature and occurrence of hazards in this region with the objectives to recommend measures for ensuring human safety within this dynamic environment. The frequency of volcanic eruptions, seismic activities, landslides, flooding and coastal erosion has had adverse consequences on human lives, property and the environment in the city. In this regard, human occupation of high-risk zones (hill slopes, floodplains, and coastal lowlands) is the source of problems of habitation in this region. Based on the concept of urbanisation, vulnerability and exposure to risk, and using the DR – Disaster Risk Index, drainage, relief, topographic maps, risk zones were identified. This paper recommends the evacuation of people from some of these risk zones and in other relocating. These hazard prone areas do not only require careful policy planning but also require a rigorous implementation of the strategic master plan of the city.

Paisagem cultural das montanhas do noroeste de Portugal: um ciclo de construção, desestruturação e reconversão

Na paisagem cultural das montanhas do Noroeste de Portugal, a estrutura de socalcos nas vertentes constitui o principal marco de identidade. Por sua vez, a prática do regadio, assente em sistemas de rega tradicionais, constitui uma estratégia essencial ao desenvolvimento das actividades agro-pastoris nos diferentes tipos de socalcos. No contexto do estudo dos riscos, o conhecimento destas vulnerabilidades é fundamental. As propostas apresentadas podem enquadrar-se na prevenção de riscos geomorfológicos, de riscos climático-hidrológicos e de riscos de incêndios florestais.

Impact assessment of proposed ski areas: A GIS approach integrating biological, physical and landscape indicators

Ski centres are characterized by significant environmental impacts that occur during both the construction and the operation phase. In Trentino, a well-known ski destination located in northern Italy, new ski areas were identified by planning tools without conducting a formal assessment of their effects on the environment. This paper presents a study to assess and compare the impacts of the proposed ski areas within two valleys strongly linked to winter tourism: the Fiemme and Fassa Valleys. The method is based on the computation of spatial indicators using a Geographical Information System (GIS) to predict and quantify critical impacts, such as ecosystem loss and fragmentation, soil erosion, geomorphologic hazards, interference with flora and fauna, and visibility. Subsequently, multicriteria analysis was applied to generate composite indices, and to rank ski areas according to their overall suitability. Finally, sensitivity analyses allowed to test the stability of the results. The study concluded that two of the proposed ski areas are located in highly unsuitable environment, and the relevant plan provisions should be revised.

Simplified planning regulations in Germany and the effects of landslides

In recent years, German laws pertaining to construction have been simplified with the goals of reducing administrative procedures and government expenditures. On the one hand, the new regulations are intended to simplify construction activities by the elimination of obstacles toward approval and by the simplification of governmental supervision procedures. On the other hand, a simplified approval process shifts the responsibility for compliance with building codes to the owners, consultants (architects, civil engineers, experts, etc.) and construction project managers. First experiences of damage to buildings show that streamlined construction approvals run the risk of neglecting basic geomorphologic and geologic fundamentals. Omissions are evident, which have led to failures at embankments and on building sites, causing considerable losses. The responsible administrations have reacted in different ways to the changed conditions, as far as they already are aware of the possible implications. In southern Lower Saxony State, the planning agencies have reacted to the growing responsibilities by attempting to determine at an early stage hazards in areas that are being developed. The practice aims to ensure that neither the planned construction activities nor the buildings themselves pose a threat for the residents. However, in the context of weighing these land-use decisions, it becomes apparent that in the future, administrative employees will have to be trained to foresee potential problems caused by the new regulations, while those affected by the decisions must receive advice on how to proceed. At the same time, latitudes and guidelines for dealing with geomorphologic hazards have to be defined.

Sequential analysis of China's hazards in geoscience

At the request of the IGU Study Group on Rapid Geomorphologic Hazards, the author has dealt with a lot of information on China's hazards in the course of compiling geomorphic hazard inventories. While analyzing those hazards throughout history, especially in the past two decades, the author found that quite many hazards used to be either interrelated or associated with each other. On the basis of a large number of eventful catastrophic cases both in China and its adjacent areas, this paper analyzes and sums up the following seven major sequences with respect to the occurrences and transformations in geo-hazards: 1) Dry-cold wind-drift sand (dust) storm type, 2) Warm-wet water-soil hazards type, 3) Wet-hot typhoon hazards type, 4) Alpine freezing-gravity hazards type, 5) Earthquake-rainstorm and mud-rock flow type, 6) Earthquake-forest fire hazards type and 7) Earthquake-tsunami hazards type.

MAPPING GEOMORPHOLOGIC HAZARDS WITH SPACE IMAGERY

A method is described for the mapping of exogenous geomorphologic hazards (mass movements, frost heaving, suffosion, melting of permafrost) in the Lake Baykal area using space imagery. Black-and-white photography from the Salyut-4 space station (1:2,100,000 scale) was used as a base for the preparation of a series of maps depicting natural conditions (morphotectonic and physical geographic regions, faults, climate, dominant exogenous processes) used as a base for compiling a map of planning and engineering measures for the prevention and amelioration of geomorphologic hazards. Translated from: Geografiya i prirodnyye resursy, 1985, No. 2, pp. 59-67.