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The objective of the Hydrological Atlas of Switzerland (HADES) is to provide a comprehensive and detailed insight into the hydrological conditions in Switzerland. It is aimed at practitioners, scientists and the general public. The HADES was launched as early as 1989 and was a printed atlas with thematic maps at a quite large scale of 1:500,000 until 2010. In addition, other products such as excursion guides and learning tools for schools have been created. The printed maps of HADES provide an excellent overview of the variability of hydrological characteristics in space. Parts of the original information, however, may disappear due to the generalization necessary for the cartographic representation. In addition, the representations are rather static from a temporal point of view as they are usually limited to a certain period of time. The new digital data and analysis platform (http://hydromaps.ch) has been designed to overcome these limitations. It enables the display of hydrological parameters on different spatial scales, which are connected to each other via a zoom function. The zoom levels are only limited by the spatial resolution and by the accuracy of the underlying data. On the time scale, the main focus is on long-term annual, monthly and seasonal averages representing climatology. The period can now be selected dynamically so that it is possible to compare different periods. Furthermore, maps of individual months or even events can also be called up for selected topics, in order to assess the deviations from the climatological mean values.On the spatial domain, more than 4000 catchments are pre-processed. Various hydrological parameters are available as spatial averages for each of these catchments. Within a catchment, for example, the parameters of the water balance can be compared. Furthermore, comparisons between different catchments are also possible. These few examples show the interactivity and usability of the new Atlas platform developed by the HADES project team. The HADES has been financed by the Swiss Federal Office for the Environment for over thirty years. It has made a successful transition from the analog static world in the 1990ies to today's digital dynamic world. It will continue to make a major contribution to Swiss hydrology. [ABSTRACT FROM AUTHOR]

Beaver (Castor fiber, Castor canadensis) are mammalian ecosystem engineers, modifying rivers and floodplains, and influencing local hydrology, geomorphology, carbon and nutrient cycling, and ecology. They construct dams, dig canals and burrows, fell trees and introduce wood into streams, which in turn impounds water and raises shallow water tables, altering the water balance, sediment transport, channel pattern, and biogeochemical cycling within aquatic-terrestrial habitats. In this cross-disciplinary study, we first synthesize beaver effects on the local hydrology, geomorphology and biogeochemistry of aquatic-terrestrial ecosystems. We then summarize results from four beaver sites in Switzerland and Germany in terms of hydrology, water biogeochemistry (nutrients, pH, dissolved oxygen, water temperature), geomorphology, dissolved/particulate organic matter concentration and composition (absorbance and fluorescence measures coupled with parallel factor analysis (PARAFAC) and RockEval-pyrolysis), macroinvertebrates (diversity, stable isotope analysis) during a complete hydrological cycle (all seasons). Results include a nitrate reduction of 17-23 % along beaver cascades, a DOC increase downstream of beaver reaches, a carbon storage increase in beaver sediments, and a spatial heterogeneity increase in macroinvertebrate food webs. Key feedbacks and overlaps among changes induced by beavers hint towards modifications in longitudinal connectivity (using drone-based remote sensing) that drive important process feedbacks. The magnitude of these feedbacks was heavily dependent on climate-landscape context as well as the ability to promote lateral connectivity determining the spatial extent of beaver effects with increasing stream order. We view these results in the context of stream management and restoration, and highlight the importance of a data-based, realistic approach towards using beavers for natural catchment management. [ABSTRACT FROM AUTHOR]

The devastating flood of 1868 in the alps triggered a systematic study of the role of forests for the hydrology in Switzerland (and neighboured countries). As a direct consequence, the first longterm observations of runoff in small forested catchments were launched in 1903 in the Swiss Emmental (and have been run ever since). Several similar longterm investigations of runoff formation in other first-order catchments of the Swiss pre-alps – with different geology, forest compositions and rainfall regimes – followed in the course of the past century, among others the 50-year old hydrological observatory in the Alptal (central Switzerland).Looking back to the history of these old pillars of forest-hydrological research, it becomes obvious that they served much more than for satisfying pure academic curiosity. The legacy of correspondence from the archive tells us that the initiative and planning of new forest-hydrological observatories was closely related with political and forest-promoting interests. In the same way, the results of these studies have been interpreted and communicated in a way that sometimes exceeded pure scientific conclusions. In fact, all these data from more nearly 120 years illustrate a very differentiated (ambiguous) relationship between the presence (and shape) of the forest and the runoff response to heavy rainfall. In contrast, the public doctrine (disseminated by both researchers and stakeholders) was often simplified and biased towards a too positive effect of forests in mitigating floods. On the other hand, the complex (differentiated) insights from numerous specific analyses of students and researchers have often been disremembered.We state that this conclusion doesn't apply only to the present case of forest hydrology, but pose a challenge for other hydrological (or: environmental) topics as well. [ABSTRACT FROM AUTHOR]