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The 16th of June 1818, the failure of the Giétro glacier in the Swiss Alps provoked an outburst flood that devastated the Bagnes valley, causing 34 deaths and major damages to buildings, road system, hydraulic infrastructures and crops. This disaster had a major impact on the economy of the valley and created a great movement of solidarity. It remains today a well-known historical natural disaster. In order to reconstruct the course of the wave and to map the flood, we used an interdisciplinary approach by crossing historical and geomorphological data. We first compiled and mapped the large number of historical data available in the local and state archives. These data were then completed by geomorphological observations made on the field and on numerical documents. The resulting map presents the spatial extent of the flood and water depths. This article shows the validity of interdisciplinary approaches for reconstructing past natural disasters. [ABSTRACT FROM AUTHOR]

An introduction to the journal is presented in which the editor discusses various reports within the issue on topics including hydrology, geophysical investigations, glacier research and environmental sciences.

Geomorphic processes driven by water are particularly active in mountain environments, especially under the current climate conditions. Erosion and dissolution processes shape meaningful landforms, in different kinds of deposits and rocks, and in some cases they are classified as geomorphosites. Such landforms, especially earth pyramids and rock pillars, are usually characterized by a high scientific value (e.g., representativeness, ecologic support role) and by additional values (e.g., cultural and aesthetic value) contributing to the local geoheritage. Mountain geomorphosites are growing in importance within scientific community and their morphological evolution can affect the global value of the site itself (e.g., integrity). In this paper, after a first review on the terminology used for classifying landforms modelled by water runoff and on their meaning within the mountain environment, the results of a detailed research performed at two sample sites, included in the Swiss National Inventory of Geosites, are presented. The two study sites are representative respectively of: i) water runoff on glacial deposits shaping earth pyramids (Pyramides d'Euseigne); ii) water dissolution on gypsum rocks, modelling articulate karst landscapes (Pyramides de gypse du Col de la Croix). For each site, landforms evolution was investigated and denudation rates were estimated by means of different methods: iconographic material analysis, quantitative geomorphology and dendrogeomorphology on exposed roots. Despite the long-term, average rates obtained by means of roots exposure for both water runoff on glacial deposits (e.g., 5.8 mm/y) and dissolution on gypsum rocks (5.6 mm/y) are comparable. Moreover, a strict relation between the activity degree of processes, the integrity of the site and the assignment of geomorphosites to a specific category (i.e., active, passive or evolving passive) emerged from the results. [ABSTRACT FROM AUTHOR]

Geoconservation has been growing in importance within the environmental management context. The conservation of geological heritage is being more and more recognised as an essential issue in nature conservation. Inventories of geosites are considered basic steps in geoconservation strategies and constitute a tool to support management considering the sites' values, use potential and risks of degradation. There are dozens of proposed methods to create inventories and to perform qualitative and quantitative evaluations of the sites and there are still discussions concerning the issues of how to select and evaluate sites and provide management guidelines. Geomorphosites are geosites with geomorphological nature and it is a category that presents some peculiarities highlighted in the literature. This work aimed at proposing a method for inventorying and assessing geomorphosites designed for territorial management focused on the use potential of the sites, divided into scientific, educational and geotouristic uses, the promotion conditions and the risks of degradation. The method was applied to the southeast coast of Rio de Janeiro State, Brazil, which has a high geomorphological diversity. The result was the creation of an inventory of geomorphosites in which all sites were described and quantitatively assessed, creating a product that can be easily applied in the management of the sites. The objective of this work was to contribute to the methodological discussions and to strengthen the insertion of geoconservation on territorial management.

Hydro-climatic changes and the increasing release of pollutants into rivers by human activities tend to affect the quality of watercourses, to alter aquatic ecosystems and to reduce the amount of useable water. The ecological and chemical states of rivers and their evolution is thus of growing concern. In Europe and Switzerland, water policies are progressively shifting towards a holistic approach of river systems. The European Commission notably established a framework to highlight rivers' ecological deficits and to enhance regional or local water management plans. In Switzerland, a similar framework is currently under development. In this paper, both procedures are compared and implemented in a Swiss catchment dominated by agricultural activities. The aim is to define the challenges that still need to be addressed to assess and sustain river health. The hydromorphological, ecological, and ecotoxicological quality of the river was evaluated. Both frameworks highlighted the fact that no section of the river can currently be classified as being in a good environmental state and that the state deteriorates as tributaries and wastewater discharge flow into the main riverbed. Chemical issues and water quality changes due to hydro-climatic variations and management strategies were also pinpointed. Both frameworks are thus useful tools to survey changes in rivers quality in space and over time. However, challenges remain regarding the appropriate strategies to monitor and analyze chemicals, the definition of target values and conditions, the evaluation and integration of human-induced pressures, and the overall evaluation of the state of a river. The development of integrated indicators or of ecosystem services approaches is considered as a potential solution to explore river health and to define efficient restoration measures by water managers.

Recent observed hydro-climatic changes in mountainous areas are of concern as they may directly affect capacity to fulfill water needs. The canton of Vaud in Western Switzerland is an example of such a region as it has experienced water shortage episodes during the past decade. Based on an integrated modeling framework, this study explores how hydro-climatic conditions and water needs could evolve in mountain environments and assesses their potential impacts on water stress by the 2060 horizon. Flows were simulated based on a daily semi-distributed hydrological model. Future changes were derived from Swiss climate scenarios based on two regional climate models. Regarding water needs, the authorities of the canton of Vaud provided a population growth scenario while irrigation and livestock trends followed a business-as-usual scenario. Currently, the canton of Vaud experiences moderate water stress from June to August, except in its Alpine area where no stress is noted. In the 2060 horizon, water needs could exceed 80% of the rivers' available resources in low- to mid-altitude environments in mid-summer. This arises from the combination of drier and warmer climate that leads to longer and more severe low flows, and increasing urban (+40%) and irrigation (+25%) water needs. Highlighting regional differences supports the development of sustainable development pathways to reduce water tensions. Based on a quantitative assessment, this study also calls for broader impact studies including water quality issues., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Purpose: To evaluate the feasibility and usefulness of a three-dimensional ultrasound (3D-US) image-guided system in identifying and tracking the tumor bed (TB) for planning and daily localization before radiation delivery for breast cancer., Methods and Materials: Twenty breast cancer patients underwent two CT scans at the time of simulation and just before their boost. Three-dimensional ultrasound images were acquired immediately after the CT scans, to which the images were automatically fused. Three-dimensional ultrasound images were also acquired immediately before treatment. Spatial and temporal TB differences between CT and US were evaluated., Results: The TB was not visible on US and CT in 1 subject who had and 1 subject who had not received chemotherapy before whole-breast radiotherapy. The mean (SD) TB volume overlap was 78% (14%). The mean centroid position of the TB on CT vs. US differed by 0.1, 0.2, and 0.4 mm in the anterior-posterior, left-right, and superior-inferior directions. The mean (SD) absolute radial displacement of the TB on each fraction from the treatment plan was 10.8 (6.3) mm., Conclusions: The TB was well visualized by US for the majority of patients. Clinically insignificant differences in the displacements calculated by paired CT vs. paired US demonstrate the feasibility of using 3D-US. The present study suggests that a 10-mm planning target volume margin could result in undercoverage of the clinical target volumes in 50% of treatments. Multimodality planning and image-guided radiotherapy with US potentially offers an accurate and non-ionizing solution for the daily definition of the TB position during partial-breast irradiation and boost treatments., (Copyright © 2011 Elsevier Inc. All rights reserved.)