Environmental Engineering Reference
In-Depth Information
and at least two theoretical approaches have been
proposed (Roe 1998; see also Holling 2000, 2001,
Gunderson & Holling 2002, van Eeten & Roe 2002).
For ecosystem and restoration ecologists dealing
directly with specific systems in specific places, the
planning and indeed all conceptual and practical
efforts in restoration need to be cognizant of two new
facts: (i) the quickly growing importance of so-called
emerging ecosystems, arising as a result of biotic
migrations, introductions and invasions that occurred
in the last century and a half, and as a result of rapidly
changing land-use patterns related to urbanization,
industrialization and globalization of commerce (Milton
2003) and (ii) the realization that a great number of
existing ecological systems around the world are
better conceived as socio-ecological systems than as
natural systems. This is because the deeply transform-
ing impact of sustained human activities has been
in motion and having impact - often irreversible -
for many millennia. In most parts of the world it is
only in the last 100-150 years that human impact has
been deep and broad enough to be noticeable - from
outer space, for example - as an indelible ecological
footprint and, consequently, for our present era to be
labelled, somewhat ominously, as the 'Anthropocene
Era' (Crutzen 2002). During this same period, the
phenomenon of emerging ecosystems has grown
gradually in scale and abundance until now it may
be considered of dramatic importance. Emerging
ecosystems are of course not new, but are now
arising in large numbers and on broader scales. While
emerging ecosystems may not sound too menacing,
it is clear that increases in global commerce and migra-
tions have led to a vastly increased spread of pests
and diseases that cause great harm when they are
transported long distances and thus divorced from their
natural predators and pathogens. The notion of
socio-ecological systems is a particularly powerful
tool in the dual effort to develop stronger links be-
tween social and ecological systems in the 'real' world
(Berkes & Folke 1998), and to forge stronger linkages
among researchers and educators in the biological
sciences and the social sciences, as well as the
broader non-scientific, non-academic portion of our
local and global societies. As a new paradigm they
also help us to take biocomplexity into account and
to strive to restore ecosystems that will be adaptive
and resilient to local surprises and to global change.
Before further exploring the way forward in restora-
tion ecology, a crucial preliminary question to ask is,
why restore ecosystems? Why invest the important
amounts of time, energy and other resources required
to actively restore, or assist in the self-restoration of,
ecosystems that have been degraded, damaged or
destroyed? Who will benefit? And, who will be
willing to pay? What are the alternatives - so-called
designer ecosystems, unmanaged emerging ecosystems,
abandoned ecosystems, etc. - and are they socially,
legally, politically and financially acceptable as
substitutes?
Simply put, three fundamental reasons to restore
ecosystems can be cited:
1
preservation of native biodiversity;
2
maintenance or improvement of sustainable econ-
omic productivity; and
3
protection - or augmentation - of our stock of
natural capital
providing a flow of ecosystem
goods and services which benefit us, and all other
species, in more ways than we can count or evalu-
ate in simple monetary terms.
Actually, the third reason is a combination of the first
two.
The first of these reasons is justifiable first and fore-
most by the inherent, innate values related to bio-
diversity. Biodiversity is a synonym for life, and thus
commands our respect, stewardship and protection
per
se
. In addition, biodiversity plays many roles in the
adaptive evolution and consequently in the function-
ing of all life-supporting ecosystems.
The second reason - sustainable economic product-
ivity - can be readily justified as well, especially in
developing countries of the south, to use the term in
its current geo-economic sense - where most people
still live directly on the land, and on natural capital,
as opposed to human-manufactured economy. Here,
the primary issues are human welfare and economic
livelihoods, as opposed to biodiversity
per se
. As
in the industrialized north, socio-ecological systems
are common, but it is in the south that the largest
expanses of more or less natural ecosystems, and the
bulk of biodiversity, also persist despite human use
and exploitation. In the geo-economic north, includ-
ing western Europe, this second justification of
restoration, which is pragmatic and economic, has rarely
