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ers and scientists to think about their unconscious
assumptions and the inherent limitations of this fi eld
of action. A central point in the essay is the need to
cope with uncertainty. The authors warned against
selecting of restoration goals and endpoints as if there
would be a specifi ed climax, for the trajectory as if this
would be repeatable in numerous locations, and for the
concept of self-organization as if one could confi ne the
restoration measures to recreating the physical varia-
bles. Based on their analysis, Hilderbrand and co-
authors recommend how to move 'beyond the myths',
recognizing and addressing uncertainty and contin-
gencies. For example: (1) restoration requires periodic
attention and
adaptive management
, (2) designing
for resilience implies planning for surprise and focusing
on a diversity of approaches, functions, and taxa,
(3) goals should include multiple scientifi cally defensi-
ble endpoints of functional or structural equivalence
and (4) invasive species should not
a priori
be ruled out,
but considered with respect to their role as compared
to native species.
Understanding uncertainty and unpredictability is a
scientifi c goal in itself. In mathematics,
chaos theory
describes the behaviour of certain systems that exhibit
dynamics that are highly sensitive to initial conditions.
The behaviour of chaotic systems may seem to be
random, but as soon as the initial conditions are
known, it can be explained deterministically. Chaos
theory can help explain incomprehensible observa-
tions. For example, Huisman and Weissing (1999),
considering the so-called paradox of the plankton - the
number of co-existing species far exceeding the number
of limiting resources at equilibrium conditions - were
able to explain species oscillations and chaos in mix-
tures of phytoplankton species by experiments and
associated models in which they had started with
slightly different initial conditions and in which the
species had complex competitive interactions. Beninca
et al
. (2008) have experimentally shown that long-
term stability is not required for the persistence of
complex food webs; interestingly, however, also irregu-
lar oscillations appear to remain within certain limits.
But, in their observations over 7 years, predictability
remained limited to a period of 14 days only.
nevertheless come back to the realm of active interven-
tions, of doing restoration, as best we can. As noted,
the holistic approach is transdisciplinary, and requires
much outreach and consensus building - network
building across professional, ideological and intellec-
tual lines. To quote Cairns and Heckman (1996), 'The
fi eld of restoration ecology represents an emerging
synthesis of ecological theory and concern about
human impact on the natural world' (p. 167).
Let us thus round off this chapter by emphasizing
that restoration ecology, which is ultimately the study
of ecological restoration, can perhaps help form an alli-
ance between science and society, in the search for a
transition to
sustainability
. On the one hand, this
interface between science and society opens up new
opportunities, and on the other hand it implies risks.
Applied sciences, or
science - in - context
, may become
politicized when scientifi c uncertainties and societal
interests are both heavily involved (Swart & van Andel
2008 ; Chapter 22 ). Looking at the ' scene ' in Europe,
today, exemplifi ed by the implementation of the nature
policy plan Natura 2000, Keulartz (2009) noted that
the 'democratization' of nature conservation policy is
fraught with problems and pitfalls and requires an
adequate and professional organization of communi-
cation between the various actors. In Slovakia, for
instance, many state-owned nature reserves have been
given back to former private owners, which has
resulted in much more limited conservation and resto-
ration measures actually being carried out, even
though there was no change in the legal protection of
the sites. Similar problems could be cited in Albania,
Italy, Greece and many other countries.
Kricher (2009) emphasizes that an understanding
of the dynamic nature of ecology and evolution is
essential to formulating environmental policies based
on ethics that can help guide humanity towards a more
responsible stewardship of our planet and all its eco-
systems. He warns against nonscientifi c, ' teleological
thinking', as if nature would or could have a goal, for
example associated with a search for equilibrium or a
'climax'. Humans set goals, not ecosystems, and if the
goals are set scientifi cally, they should include esti-
mates not only of means but also of the transient
nature of ecosystems, with all their uncertainties and
sudden opening of opportunities. Coping with uncer-
tainty is primarily a scientifi c task, to try and quantify
the risks of deviation from means and equilibria,
but this issue should be communicated with all the
stakeholders in ecological restoration projects and
2.6.2
Science and Society
After considering the irrefutable and implacable reality
of uncertainty and unpredictability in nature, we must