|
The overall biomass of herbivores in alpine environments is generally low. Nevertheless,
due to their heterogeneous distribution, selective feeding and fluctuating populations the impact of
herbivores on ecosystems may be very high in some areas and in some years.
Many alpine communities are clearly influenced by the activities of herbivores.
Herbivores affect the structure and function of plant communities by the selective removal of plant
material, by their mechanical impact, and by their influence on nutrient cycling and competitive
interactions between plants.
While plant-animal interactions in the alpine environment are relatively similar to
those of lowland environments, the modification of the nutrient cycle probably plays a more pronounced
role due to the overall slow mineralization rate in alpine environments.
In addition, the fragile alpine environment is more susceptible to deleterious effects,
because the low productivity can be further reduced by a high herbivore pressure. Where herbivores are
so abundant that they destroy the vegetation, there is a high risk of severe erosion.
While all major groups of herbivores are often present in alpine environments, their
relative abundance and impact may be quite different from that in many lowland situations. Invertebrate
herbivory may be of lesser importance in the alpine environment while herbivory and trampling by
large mammals may be of overriding importance.
|
back
to top