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Cosandey L.,Federal Office for the Environment
Proceedings of Forum Acusticum

Over the past 20 years, more than 1 billion Euro have been invested for noise mitigation along the Swiss road network. The first priority was the remediation of the highways, along which nearly 200'000 people have already been protected. Nevertheless, more than one million people (15% of the Swiss population) still suffer from road traffic noise exceeding the threshold limits, set at 60 dBA days and 50 dBA nights. Due to the urban sprawl and the development of agglomerations over the last two decades, road noise has become an urban problem. A recent survey shows that almost 2 billion Euros will have to be invested until 2018 for completing the noise remediation of Switzerland's road network. A new strategy focusing on measures that are efficient in urban conditions is now being implemented. Priority is set on noise emission control at source: low noise pavements, low noise tires, traffic calming. The necessary noise reduction of 10 dB can only be achieved with the combination of these measures. Source

Kuchli C.,Federal Office for the Environment

Diverse developments in the economic context of forests played an important role in the realization of the sustainability concept in Swiss forests. The construction of railways in the 1850s was decisive because it allowed the importation of coal, fertilizers and food. The age of coal enabled industrialization. The first train entered Bern in 1858, and within two years coal had become cheaper than firewood in the city. The most important article of the national forest law pertains to forest area, which may not decrease in size unless it is in the overarching public interest, for example the construction of a railway line. If an area of forest is cleared, an equivalent area elsewhere must be afforested. In refining Gurnaud's method, which enabled the measurement of tree growth in stands of trees with differing diameters, Biolley laid an important foundation for the liberation of foresters away from the chessboard approach towards a more subtle approach that allowed uneven-aged stands. Source

Arborino T.,Canton of Wallis Sion | Jordan J.-P.,Federal Office for the Environment
Swiss Competences in River Engineering and Restoration - Special Session on Swiss Competences in River Engineering and Restoration of the 7th International Conf. on Fluvial Hydraulics, RIVER FLOW 2014

More than 13,000 hectares of land in the Rhone Plain upstream from Lake Geneva are currently susceptible to flooding, including a high-density development zone covering an area of around 1,000 hectares. There are plans to invest more than 1 billion euros until 2030 in order to protect the Rhone Plain against hundred-year floods, and the agglomeration against thousand-year floods. The construction work will take several decades, and during this period a suitable response is to be made to the legitimate urgent calls for flood protection measures so that the development of the region can proceed without increasing the degree of risk. In order to secure the necessary level of acceptance for this major project, rapidly implementable structural measures, adapted land use planning and transparent communication about the degree of risk, will be essential. © 2014 Taylor & Francis Group, London. Source

Buhlmann T.,University of Basel | Hiltbrunner E.,University of Basel | Korner C.,University of Basel | Rihm B.,Meteotest | Achermann B.,Federal Office for the Environment
Atmospheric Environment

During the past century atmospheric nitrogen deposition increased dramatically due to human activities worldwide. Currently, it exceeds the critical load for nitrogen (CLN) in over 90% of the Swiss forest area and raised bogs, in 80% of all fens and in 30% of species-rich grassland areas in Switzerland. Indirect gaseous nitrogen losses (HNO2, NO, N2O, N2) from these soils induced by atmospheric nitrogen deposition are likely to be substantial. However, the approaches to estimate these indirect N emissions provided by the international organisations (UNFCCC, IPCC; UNECE, EMEP/EEA) are based on agricultural data only. They may not be suitable to estimate the indirect emissions from (semi-)natural ecosystems such as forests, extensively used grassland, and wetlands. The present study aims at calculating ecosystem-specific annual indirect N2O and NO emissions of (semi-)natural ecosystems in Switzerland for the years 1990, 2000, 2007 and 2010 using a simple linear model similar to the international guidelines. The approach here is based on empirical data for (semi-)natural ecosystems, derived from a literature survey, is driven by atmospheric nitrogen deposition and is ecosystem-specific with a high spatial resolution of 100m×100m. Our results show that such ecosystems represent a strong source of indirect N emissions induced by atmospheric nitrogen deposition and emitted 1.61±0.32Gg N2O-N and 2.51±0.53Gg NO-N into the atmosphere in Switzerland in the year 2010, corresponding to 21% of the total Swiss N2O emissions and 10% of the NOx emissions. Thanks to the reduction of N emissions and thereby reduced atmospheric N deposition, the indirect N2O and NO emissions from (semi-)natural ecosystems are estimated to have been both reduced by c. 20% from 1990 to 2010. We conclude that the source strength for N2O and NO emissions of (semi-)natural ecosystems have been underestimated by the current approaches of IPCC and EMEP/EEA by a factor of 4.4 and 17, respectively. In regions and countries with a high fraction of (semi-)natural ecosystems, the approach offered here has the potential to improve the estimate of indirect N emissions substantially. © 2014 Elsevier Ltd. Source

Strozzi T.,Gamma Remote Sensing | Ambrosi C.,University of Applied Sciences and Arts Southern Switzerland | Raetzo H.,Federal Office for the Environment
Remote Sensing

An inventory of landslides with an indication of the state of activity is necessary in order to establish hazard maps. We combine interpretation of aerial photographs and information on surface displacement from satellite Synthetic Aperture Radar (SAR) interferometry for mapping landslides and intensity classification. Sketch maps of landslides distinguished by typology and depth, including geomorphological features, are compiled by stereoscopic photo-interpretation. Results achieved with differential SAR interferometry (InSAR) and Persistent Scatterer Interferometry (PSI) are used to estimate the state of activity of landslides around villages and in sparsely vegetated areas with numerous exposed rocks. For validation and possible extension of the inventory around vegetated areas, where InSAR and PSI failed to retrieve displacement information, traditional monitoring data such as topographic measurements and GPS are considered. Our results, covering extensive areas, are a valuable contribution towards the analysis of landslide hazards in areas where traditional monitoring techniques are sparse or unavailable. In this contribution we discuss our methodology for a study area around the deep-seated landslide in Osco in southern Switzerland. © 2013 by the authors. Source

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