Geoscience Reference
In-Depth Information
retain their structure and functionality in the face of challenges because
they are
.
49
'
able to respond in a
exible way to uncertainty and surprises
'
Resilience, when it is understood as a system
'
s capacity to adapt
without undergoing a qualitative shift, has rami
cations for the way in
which we should control our activities. Changes in state occur when an
ecosystem, whilst undergoing renewal and reorganisation in response
to disturbance, lacks the resilience to maintain its existing regime.
50
It
is well-established that the cumulative effects of human actions tend
to erode the ability of ecosystems to cope with change, including through
a combination of eradicating important systemic components (e.g., top
predators), altering conditions (e.g., through an excess of nutrients) and
modifying patterns of disturbance (e.g., through anthropogenic climate
change).
51
Folke et al. refer to a wide range of regime shifts in terrestrial,
freshwater and marine ecosystems, all of which, it has been argued,
were associated with a loss of resilience due to factors including over-
exploitation, pollution and the destruction of habitat.
52
Many of these
shifts, because the ecosystems lacked the capacity to retain the trappings
of their prior state, resulted in systems that were
and con-
sequently unable to support a diverse biotic community.
53
The clear
conclusion from this is that we need both to re
'
simpli
ed
'
ect on how our acts
combine to undermine the ability of ecosystems to remain in states that
provide support for our own existence, and also to start determining
what we do by reference to the potential for activities, individually or in
combination, to erode resilience.
ed and general resilience
The term resilience captures a variety of respects in which an ecosystem
2.3.1
Speci
s
exposure to risks of regime change can be evaluated. Accordingly, answers
to questions concerning systemic resilience depend on the risk under
consideration. Ecological scienti
'
es the position some-
what by using two categories to distinguish between sources of resilience
and approaches that should be adopted to prevent their erosion: speci
c literature simpli
ed
49
Holling and Gunderson,
'
Resilience and Adaptive Cycles
'
, p. 32; Gunderson,
'
Ecological
, 428.
50
See Chapter 2,
Section 2.2.2
.
51
Folke et al.,
Resilience
'
'
Regime Shifts
'
, 568; Gunderson,
'
Ecological Resilience
'
,428
-
30; Folke,
'
Resilience
'
,257
-
8; Allen et al.,
'
Commentary on Part One Articles
'
,pp.10
-
11.
52
Folke et al.,
53
'
Regime Shifts
'
, 568.
Ibid
., 568.
