BIOL 1070 Study Guide - Final Guide: Intermediate Disturbance Hypothesis, Woodlot, Ecosystem Management
23 Apr 2016
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Intermediate disturbance hypothesis: the intermediate disturbance hypothesis (idh) predicts that the highest species richness will occur at an intermediate level of intensity or frequency of natural disturbance. This is because low levels of disturbance do not create many habitats to support a variety of species, whereas high levels of disturbance will eliminate many habitats that support species diversity. Communities are constantly changing in response to varying levels of disturbance. For example, when a single tree falls in a woodlot it creates a gap that has higher levels of light, which support a new community of species. These species are optimally suited to high light conditions in which they can establish themselves and out-compete other shade tolerant species. Large, infrequent, disturbances are often catastrophic and include disturbances such as floods, forest fire, hurricanes and volcanic activity. A woodlot may be transformed by a severe fire into an open field dominated by herbs and grasses.
