Nepal is a mountainous, less developed kingdom that straddles the boundary between the Indian and Himalayan tectonic plates. In Nepal, landslides represent a major constraint on development, causing high levels of economic loss and substantial numbers of fatalities each year. There is a general consensus that the impacts of landslides in countries such as Nepal are increasing with time, but until now there has been little or no quantitative data to support this view, or to explain the causes of the increases. In this paper, a database of landslide fatalities in Nepal has been compiled and analysed for the period 1978-2005. The database suggests that there is a high level of variability in the occurrence of landslides from year to year, but that the overall trend is upward. Analyses of the trends in the data suggest that there is a cyclicity in the occurrence of landslide fatalities that strongly mirrors the cyclicity observed in the SW (summer) monsoon in South Asia. Perhaps surprisingly the relationship is inverse, but this is explained through an inverse relationship between monsoon strength and the amount of precipitation in the Hill District areas of Nepal. It is also clear that in recent years the number of fatalities has increased dramatically over and above the effects of the monsoon cycle. Three explanations are explored for this: land-use change, the effects of the ongoing civil war in Nepal, and road building. It is concluded that a major component of the generally upward trend in landslide impact probably results from the rural roadbuilding programme, and its attendant changes to physical and natural systems.

A research programme underway in south-east Spain has the overall aim of developing a long-term landscape evolution model for the Tertiary depositional basins that lie within the eastern part of the Betic cordillera. As part of the work it has become apparent that there are multiple natural hazards to development in the region, and the nature and distribution of these is presently under investigation. For one hazard, namely landsliding, a database of over 300 cases has been compiled within one defined 425 km 2 river catchment, namely the Río Aguas. Evaluation of the database has demonstrated that the contemporary distribution of landslides correlates with areas of steepest slopes across a range of the different lithologies. However, the "slope" component of the landscape is controlled by a wave of incision associated with a river capture event c. 100000 years ago which locally increased erosion by between 5 and 10 times. This event was a function of differential uplift between the depositional basins and resulted in over-steepened slopes within parts of the catchment which have yet to reach equilibrium in this evolving landscape.

Terrain analysis studies for long linear engineering projects provide critical engineering geological and geomorphological data that inform project design options, route selection and construction methodologies. This paper introduces the use of geomorphic indices alongside methods of aerial photograph interpretation and remote sensing in the desk study phase of engineering terrain evaluations in the identification of landscape changes and geohazards in active tectonic regions. Three geomorphic indices (hypsometry, river long profile analysis and stream-length gradient index) are applied to freely available DEM data in order to develop the qualitative and quantitative (relative to study area) understanding of how the hillslope and river systems respond to the effects of tectonic activity and climate change. A hypothetical pre-feasibility study corridor (10 km width) located in the Sorbas Basin (SE Spain) is used to develop the methods of application, which could represent a proposed rail, road or pipeline routing. The results of the scaled indices approach, from catchment to reach (i.e. section of uninterrupted river channel) investigations, indicate a variable response of

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The definitions of hazard and risk in natural hazard studies are well established in the scientific literature. However, many examples of ‘landslide hazard assessment’ only identify the susceptibility of slopes to failure and make no statement on the frequency of occurrence that would be necessary for a complete hazard evaluation. In a research programme undertaken in SE Spain the issue of landslide susceptibility in a semi-arid, neotectonic environment was examined, with some attempt to evaluate the hazard. This work involved establishing the occurrence of landsliding within the 550 km 2 Río Aguas catchment through remote sensing interpretation and field mapping. These data were compiled in an inventory containing the records of nearly 250 landslides that was analysed to establish the nature and extent of landslide susceptible situations. Within the catchment anticipated combinations of geological materials proved to be susceptible to failure, and relationships between landslide volume and travel angle were examined in relation to standard models. The highest incidence of contemporary landsliding appeared to be related to the proximity of a major river capture site, a geomorphological event that had been dated at 100 000  BP . This produced localized rapid incision, a ten fold increase in sediment removal and the creation of oversteepened slopes that were only recently degrading to their long-term angle of stability. In addition to contemporary landslides, field mapping identified anomalous geological structures that proved to be degraded erosional remnants of ancient landslides. Relating these remnants to the river terrace sequence in the region provided some control on the relative ages of these ancient or ‘fossil’ landslides. It was concluded that any assessment of landslide risk in the study area would need to take into account not only geological materials and the contemporary geomorphological environment but also the geomorphological history of the region.