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Disturbances are an important component of
all ecosystems. They represent one of the main types of factor that determine the spatial structure and
temporal dynamics of ecosystems. Low to moderate levels of disturbances often increase the heterogeneity
and diversity of ecosystems.
The distinct climate
of alpine environments lead to special physical conditions and high
levels of disturbances. They can also modify
disturbances originating from other causes (e.g. disturbances caused by
animals or humans).
The disturbance regime means the spatial and temporal
distribution of all types of disturbances which occur in a particular area. Disturbance in alpine areas
is often of higher intensity or frequency than in the lowlands and there may be
many different types of disturbances acting over small distances. Furthermore,
the special physical environment, especially the low temperature, leads to a slower
response/regeneration of vegetation following disturbance. For this reason, alpine ecosystems are
generally more affected by disturbance than most lowland environments.
The various types of disturbance typical of alpine environments (see below) differ in
many respects, including average frequency, spatial extent, and their effects on plants and animals.
The severity, i.e. the impact on the organisms or community, can also vary widely. Types of disturbance
which occur regularly or are restricted to certain localities are more "predictable" for organisms and
their effects may be less devastating than "unpredictable" events.
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