Small regime shifts change abundance while catastrophic exotic ones flip whole systems

Evidence

At disturbance regimes only slightly different from the historic one, the consequence to community composition may only be a shift in relative abundance rather than loss of species. Catastrophic exotic disturbances, on the other hand, may shift the entire system to a new “domain of attraction” [sensu Holling, (1973)] in which population interactions and disturbance patterns are now relevant to the maintenance of a new (global) equilibrium. Such a shift is often associated with a loss of species diversity. — S. T. A. Pickett and P. S. White, eds., The Ecology of Natural Disturbance and…, 1934

Categorization

• DEFINE: Introduces ‘domain of attraction’ from Holling - the regime-flip concept that identifies exotic (non-historic) disturbance.
• SEED: Read ‘what happened here’ as: did the disturbance stay within historic parameters (shift in abundance) or cross into a new domain (biodiversity loss)? The diagnostic distinction for field reading.
• XREF: connects to: Ecological systems flip catastrophically once crossed thresholds are reached. — Richard J. Lazarus, The Making of Environmental Law, 86