Development of Vegetation Pattern in Primary Successions on Glacier Forelands in Southern Norway

Abstract

This study evaluates spatial patterns exhibited by dominant woody plant species on terrain of increasing age in front of retreating glaciers. It analyses distribution patterns in terms of their correlation to geomorphological features on the glacier forelands, dispersal mechanisms and the time component. It is envisaged that a mix of these factors plays a major role in the development and change of the distribution patterns of the selected species and that this role should be incorporated in the interpretation of the more traditional analyses of primary successions in those areas (e.g. gradient analysis, correlation of environmental factors with vegetation). Vegetation pattern development on five glacier forelands in southern Norway was analysed using a fragmentation index, an autocorrelation measure and fractal dimension. Results show that the dispersal mode of the investigated plants (wind or animal dispersed) influences the way distribution patterns develop over a time span of about 250 years. It is also evident that there are pronounced differences between high and low altitude glacier forelands in terms of the vegetation patterns developing over time. Finally, it is argued that a suite of analytical tools and methods is more appropriate for interpreting the ecological processes on glacier forelands than the use of any single method.