Relation between landform and vegetation in alpine regions of Wallis, Switzerland. A multiscale remote sensing and GIS approach

Abstract

The analysis of habitat factors for the distribution of vegetation based on the analysis of landform characteristics is an important aspect in the process of understanding high mountain ecology. Therefore in the present study a GIS and remote sensing based approach is followed to produce different scale vegetation maps for a study area in the Western Alps Switzerland). As spatial information on site factors is commonly lacking in mountain areas, the use of a Digital Elevation Model (DEM) is a potential substitute for use in vegetation analyses, as it highly correlates with temperature, moisture, geomorphological processes and disturbance factors. Thus it is crucial to analyse the capabilities of a DEM for indicating onditions in a landscape characterised by high topodiversity and a patchwork of microclimatic habitats. Appropriate landform parameters have been derived, indicating temperature and moisture distribution, exposure towards wind, snow etc. . Using contingency tables and principal components analysis the overall influence of topography and landform on vegetation distribution was analysed. Nevertheless, the lack of information on the human dimension leads to some uncertainties in the interpretation of spatial patterns of vegetation. Additionally landform classification schemes decomposing the landscape into basic landform-elements only proved useful for characterising azonal, non-altitudinal vegetation classes.