Environmental Engineering Reference
In-Depth Information
EDITORS' INTRODUCTION
valued in terms of scientifi c validation, societal needs
and available budgets for execution and monitoring.
We start our topic by giving a brief overview of
changing points of view on nature and on the goals of
nature management, along with changes in the human
society (Chapter 1). In brief, this implies a change from
human dependence on nature towards nature's
dependence on human management. In Chapter 2, we
present some of the key concepts in the fi eld of restora-
tion ecology where for example we explain how to dis-
tinguish between the reintegration of disrupted and
dysfunctional landscapes, the restoration of degraded
ecosystems, and the rescue of biodiversity through the
reinforcement or reintroduction of species populations.
We also discuss such concepts as stability, the func-
tional role of biodiversity, reference systems and how
stocks of natural capital allow the fl ow of ecosystem
services. However, we note that despite recent progress
huge uncertainties and unknowns remain in our fi eld.
In Chapter 3, our colleague Richard Hobbs pays
explicit attention to this problem, helping the reader
focus on the challenge of coping with ongoing changes
in climate even as we set about the restoration of
degraded ecosystems in the context of highly modifi ed
landscapes. Indeed, an intriguing and important ques-
tion is to what extent historical knowledge and per-
spective can continue to be applicable if we are restoring
now 'towards the future', as we put it in the preface.
Finally, David Tongway and John Ludwig describe an
approach to landscape-scale restoration that empha-
sizes the need for understanding how ecosystem proc-
esses are affected by disturbances, causing landscapes
to be dysfunctional (Chapter 4). This knowledge can
then be used by practitioners to set achievable goals,
and to design and implement restoration technologies
to achieve their goals.
In summary, this fi rst part of our topic sets the scene
for all that follows. Rather than giving a complete over-
view, we aim at highlighting topics that we consider to
be necessary elements for the reader who will here dis-
cover the rapidly growing, and evolving, fi eld of restora-
tion ecology; we hope it will give you an appetite to carry
on reading the topic and at least some of the references
cited and, above all, to start thinking about concepts and
strategies for differing biophysical and sociocultural
contexts where ecological restoration is needed.
Rather than being just concerned and conservative
about remains of 'wild nature', ecological restoration
requires a dynamic, adaptive approach to problem
solving and resource management, especially in this
era of rapid and irreversible change in climate, land
use and species assemblages. Indeed, evolutionary and
environmental dynamics, such as invasions of species
outside their recent biographical ranges, and anthro-
pogenic climate change, can no longer be denied or
ignored, as was often the case when ecological restora-
tion was associated solely with nature conservation
concerns. However, as we think about potential future
developments in ecological restoration, we must
respect the historic roots of our human societies, and
the relationship between them and nonhuman nature
as well. Evolution of species has been a natural phe-
nomenon throughout the history of life on Earth, but
the direction and speed for some species have been
strongly infl uenced by human activities, such as plant
and animal breeding, and also indirectly affected by
our growing impact on global, regional and local envi-
ronments. Similarly, climate change has been a natural
phenomenon since the very beginning of the Earth's
existence, but the recent rate of change is recognized
by all experts as being largely due to human impact.
This is one of the main reasons why humanity
must accept responsibility for its actions, and include
nature management in the decision-making process of
planning towards a sustainable and desirable future -
especially as we climb from the current 7 billion people
to an estimated 9-10 billion in the next 25 years.
Not only does nature alter in response to changes in
environmental conditions, but also human societies
change and adapt to new conditions. Wilderness,
earlier considered as areas to be exploited for human
well-being, is nowadays valued as near-natural ecosys-
tems to be cherished and protected. Similarly, what was
earlier considered as 'wastelands' may now be called
seminatural ecosystems; if fi nancing is provided, even
derelict and devastated post-mining areas may effec-
tively be revegetated, rehabilitated and 'recycled' into
the mainstream of society. However, for ecological res-
toration to be successful, a fi rm agreement is required
between all the stakeholders. Opportunities have to be
