© COPYRIGHT 1998
Ecosystems tend to organize around stable states (attractors) which are quite resilient, that is they do not change in the face of external change...that is until a critical threshold is reached.
When a critical threshold is reached, a small external change, perhaps due to random variability, can result in a dramatic and often permanent reorganization of the ecosystem, a flip.
Oligotrophic/ eutrophic example, two resilient phases and a transition phase.
Carpenter, S. R. and Cottingham, K. L. Resilience and restoration of lakes. Conservation Ecology. 1997; 1(1):Article 2. www.consecol.org/vol1/iss1/art2/
Kay, James. Some notes on: The Ecosystem Approach, Ecosystems as Complex Systems Murray, Tamsyn and Gallopin, Gilberto, eds. Integrated Conceptual Framework for Tropical Agroecosystem Research Based on Complex Systems Theories; CIAT, Cali, Colombia. Cali, Colombia: Centro Internacional de Agricultura Tropical, 1997; c1997: 69-98. www.fes.uwaterloo.ca/u/jjkay/pubs/nac
Ludwig, D.; B. Walker, B., and Holling, C. S. Sustainability, stability, and resilience. Conservation Ecology. 1997; 1(1):Article 7. www.consecol.org/vol1/iss1/art7
Regier, H. A. and Kay, J. J. An Heuristic Model of Transformations of the Aquatic Ecosystems of the Great Lakes-St. Lawrence River Basin. Journal of Aquatic Ecosystem Health. 5:3-21. 1996.
Scheffer, M. Ecology of Shallow Lakes. London: Chapman and Hall; 1998;
Updated 17 October, 1998
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