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Zernez, Switzerland

Karthauser J.M.,South Essex Marshes | Filli F.,Swiss National Park | Mose I.,University of Oldenburg
Eco.mont | Year: 2011

Almost all protected areas nowadays rely on the sound support of the local population. More than for every other type of nature reserve, this might be the case for UNESCO biosphere reserves. A participatory and transparent approach that takes into consideration the views of all stakeholders involved is crucial for the successful progress of the project. In 2007 we interviewed 191 residents and 178 visiting tourists in the Val Müstair (Canton of Grisons, Switzerland) with standardized questionnaires to analyse acceptance of the - at that time - proposed biosphere reserve (BR). Both groups perceived the landscape of the study region similarly but had different demands regarding the BR. While tourists had a rather emotional approach, residents clearly had more hopes for economic benefits generated through the project. However, the way the residents intend to attain these benefits fits in well with the ideas of sustainable tourism promoted by BRs. Therefore we consider this gap to be easily bridged, with both groups agreeing on a successful regional marketing for the Val Müstair BR - Swiss National Park in the future. © Ivo I. Andri. Source

Kneubuhler M.,University of Zurich | Damm A.,University of Zurich | Schweiger A.-K.,Swiss National Park | Risch A.C.,Swiss Federal Institute of forest | And 2 more authors.
IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing | Year: 2014

Remote sensing offers an objective and efficient way to monitor ecosystem properties including their spatial variability across different land cover types. Especially, the representation of gradients of biochemical and structural properties of ecosystems using continuous fields (CF) approaches bears advantages compared to discrete land cover classification schemes. This paper presents a concept to synergistically generate CF maps of an alpine ecosystem parameter, i.e., total surface water content, from imaging spectrometer (IS) data. Further, the potential of linking such maps to ecological patterns, i.e., the spatial distribution of large ungulates is being assessed. In vegetated areas, total surface water content is considered as a surrogate of plant physiological status. Water is, besides temperature, light, or nutrients, an important limiting growth factor determining biomass production and therefore potential animal forage quantity in alpine grasslands. Resource ecology interested in trophic interactions between large ungulates and their forage requires spatial and temporal information on ecosystem properties and processes. The study area is located in the upper Trupchun Valley (Val Trupchun) in the Swiss National Park (SNP). The valley is famous for its high densities of chamois (Rupicapra rupicapra L.), ibex (Capra ibex L.), and red deer (Cervus elaphus L.). CF maps of total surface water content were derived from Airborne Prism EXperiment (APEX) IS data collected over the SNP in June 2010 and 2011. Abundance maps of predominant land cover classes were derived from linear spectral mixture analysis (SMA). They were then combined with water content information of the respective land cover originating from either empirically or physically based approaches. The resulting CF maps depicted a spatially continuous representation of relative total surface water content. APEX IS data from two consecutive seasons revealed differences in total surface water content in June 2010 and 2011, predominantly related to an advanced phenological development in spring 2011 and to considerable differences in snow cover between the 2 years. Linking total surface water content of grasslands to observed ungulates spatial distributions did not reveal any statistically significant patterns of habitat use. We conclude that water availability in Val Trupchun may not be the dominant limiting factor for potential forage quantity (biomass), or that ungulates choose their grazing sites based on other criteria, i.e., high nutritious quality (P, N). Nevertheless, multitemporal CF maps derived from APEX IS data were found to provide spatially explicit and fine-scaled information for analyses of an ecosystem's total surface water content. The combination of multitemporal CF maps of a wide range of ecosystem parameters and more accurate and extensive observations of animal habitat use will contribute to ongoing and future vegetation-ungulates research in the SNP. © 2014 IEEE. Source

Risch A.C.,Swiss Federal Institute of forest | Haynes A.G.,Swiss Federal Institute of forest | Busse M.D.,U.S. Department of Agriculture | Filli F.,Swiss National Park | Schutz M.,Swiss Federal Institute of forest
Ecosystems | Year: 2013

Grasslands support large populations of herbivores and store up to 30% of the world's soil carbon (C). Thus, herbivores likely play an important role in the global C cycle. However, most studies on how herbivory impacts the largest source of C released from grassland soils-soil carbon dioxide (CO2) emissions-only considered the role of large ungulates. This ignores all other vertebrate and invertebrate herbivores and their collective effects on ecosystem properties. We progressively excluded large, medium, and small vertebrates and invertebrates from two subalpine grasslands (productive, heavily grazed short-grass; less productive, lightly grazed tall-grass) using size-selective fences, assessed the impact on soil CO2 emissions and related biotic and abiotic variables. Exclusion resulted in significant changes in soil CO2 emissions in both vegetation types. Short-grass soil CO2 emissions progressively increased when large and medium mammals were excluded. However, no difference was detected among plots were all or no herbivores grazed. In contrast, tall-grass soil CO2 emissions were not affected by mammal exclusion, but excluding all herbivores lead to reduced emissions. Soil micro-climatic parameters best predicted the patterns of soil CO2 emissions in short-grass vegetation, whereas root biomass was the best predictor of CO2 release in tall-grass vegetation. Our results showed that diverse herbivore communities affect soil respiration differently than assumed from previous studies that only excluded large ungulates. Such information is important if we are to understand how changes in herbivore species composition-as could happen through altered management practices, extinction or invasion-impact grassland C storage and release. © 2013 Springer Science+Business Media New York. Source

Fatehi P.,University of Zurich | Damm A.,University of Zurich | Schweiger A.-K.,Swiss National Park | Schaepman M.E.,University of Zurich | Kneubuhler M.,University of Zurich
IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing | Year: 2015

Aboveground biomass (AGB) of terrestrial ecosystems is an important constraint of global change and productivity models and used to assess carbon stocks and thus the contribution of vegetated ecosystems to the global carbon cycle. Although an indispensable and important requirement for decision makers, coherent and accurate estimates of grassland and forest AGB especially in complex environments are still lacking. In this study, we aim to assess the capability of two strategies to map grassland and forest AGB in a complex alpine ecosystem, i.e., using a discrete as well as a continuous field (CF) mapping approach based on imaging spectroscopy (IS) data. In situ measurements of grassland and forest AGB were acquired in the Swiss National Park (SNP) to calibrate empirical models and to validate AGB retrievals. The selection of robust empirical models considered all potential two narrow-band combinations of the simple ratio (SR) and the normalized difference vegetation index (NDVI) generated from Airborne Prism Experiment (APEX) IS data and in situ measurements. We found a narrow-band SR including spectral bands from the short-wave infrared (SWIR) (1689 nm) and near infrared (NIR) (851 nm) as the best regression model to estimate grassland AGB. Forest AGB showed highest correlation with an SR generated from two spectral bands in the SWIR (1498, 2112 nm). The applied accuracy assessment revealed good results for estimated grassland AGB using the discrete mapping approach [R2 of 0.65, mean RMSE (mRMSE) of 0.91 t · ha-1, and mean relative RMSE (mrRMSE) of 26%]. The CF mapping approach produced a higher R2 (R2 = 0.94), and decreased the mRMSE and the mrRMSE to 0.55 t · ha-1 and 15%, respectively. For forest, the discrete approach predicted AGB with an R2 value of 0.64, an mRMSE of 67.8 t · ha-1, and an mrRMSE of 25%. The CF mapping approach improved the accuracy of forest AGB estimation with R2 = 0.85, mean RMSE = 55.85 t · ha-1, and mean relative RMSE = 21%. Our results indicate that, in general, both mapping approaches are capable of accurately mapping grassland and forest AGB in complex environments using IS data, whereas the CF-based approach yielded higher accuracies due to its capability to incorporate subpixel information (abundances) of different land cover types. © 2015 EU. Source

Rehnus M.,University of Natural Resources and Life Sciences, Vienna | Palme R.,University of Veterinary Medicine Vienna | Filli F.,Swiss National Park | Hacklander K.,University of Natural Resources and Life Sciences, Vienna
Mammalia | Year: 2010

In temperate climates mammals might show elevated glucocorticoid secretion in winter to facilitate catabolism. We investigated the influence of season on the concentration of faecal glucocorticoid metabolites (GCMs) in mountain hares throughout the course of 1 year. The results show that mountain hares did not have higher GCM values in winter. Our results suggested that this lagomorph copes with harsh envir-onmental conditions by reducing metabolic rate instead of depleting fat reserves. © 2010 by Walter de Gruyter Berlin New York. Source

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