Biology Reference
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Figure 2.5. Diagram showing five general types of hypothesis explaining why ecological systems tend to be stable in spite of the presence of biotic
instabilities and environmental stochasticity. According to the first hypothesis (1) a systemmoves from biotic instability to a stable equilibrium because of an
increase in stabilizing mechanisms. According to the second hypothesis (2) a system moves from biotic instability to persistence because of ''applied
disturbance patterns'' which reduce over-exploitation of resources and hence competitive exclusions. According to the third hypothesis (3) a systemmoves
from stochastic domination to persistence when stochastic effects are reduced by increasing compensatory mechanisms . According to the fourth and fifth
hypotheses, a system moves from biotic instability (4) or from stochastic domination (5) to greater stability by integrating it into a larger landscape. From
DeAngelis and Waterhouse (
1987
). Reprinted by permission of the authors and the Ecological Society of America.
