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to use cost–benefit analysis based on ecologically
uninformed preferences.
The above-mentioned approaches to valuation
are based on assumptions about stability and near-
equilibrium dynamics of ecosystems. Yet a growing
body of literature has documented a pattern of
ecological surprise and policy response in managed
resource systems. Walters (1986) first described a
rhythm of crisis and opportunities in resource sys-
tems. The six ecological histories of regional scale
systems in Gunderson and others (1995) all follow
the model of a resource crisis, followed by policy
reformation, and renewal. Similar patterns are de-
scribed in local, small-scale resource systems by
Berkes and Folke (1998) and in large, North Ameri-
can bureaucratic management systems by Johnson
and others (1999).
One of the problems with cost–benefit ap-
proaches is that by applying these techniques (fo-
cused as they are on a single desirable equilibrium)
to set policy, an inevitable ‘‘surprise’’ or policy crisis
occurs. This has been described as a pathology of
resource management (Holling and Meffe 1996),
where management actions initially are successful,
leading to a myopia of research and management
and eventual reduction in the resilience of the
ecosystem.
Ecological resilience is overwhelmed by a number
of pathways. One is through extractive activities,
such as soil removal, that reduce key sources of
capital within a system. Other activities change the
nutrient status of ecosystems—nutrient additions
can lead to change in the domains of trophic status
in lakes (Carpenter and Cottingham 1997) or in
wetlands (Gunderson 1999). Human activities, such
as agricultural irrigation, lead to broad-scale changes
in land-use patterns that lead to broad-scale col-
lapses due to salinization or sequestration of heavy
metals. Harvesting can lead to shifts in ecosystem
structures through switches in trophic relationships
in freshwater lakes (Carpenter and Kitchell 1993) or
coral reefs (McClanahan and others 1996).
Many resource crises occur at tractable (that is,
local) spatial scales and hence allow for linkages
across scales for recovery and renewal. Anotherway
of saying this is that technology increases the scale
at which key processes affect the system and over-
whelms the resilience of ecosystems at local scales.
As the degree of human impact continues to in-
crease in extent, a key unanswered question is
whether the adaptive capacity of both ecological
and social systems can keep pace with this expand-
ing human footprint.