Environmental Engineering Reference
In-Depth Information
restoration or rehabilitation intervention, be it con-
ceived at the ecosystem level, the landscape level or
the ecoregional level. Instead, ecological restora-
tion projects need broad suites of relevant, reliable and
complementary traits or ecosystem attributes that
together describe and reflect the structural, com-
positional and functional dynamics of an ecosystem
at any given point in time and can be monitored over
time to provide a moving picture, and not just a snap-
shot. At the next higher hierarchical level, the same
reasoning applies to the agglomeration of interact-
ive ecosystems that ecologists label as landscapes
(Aronson and Le Floc'h 1996a), except that socio-
ecological or human ecological attributes must be
added to the physical, pedological and biological ones.
Over time, these suites of indicators should reveal
ecosystem or landscape responses to new manage-
ment practices, including those conceived within a
CMR framework. In addition, they should help
reveal when and how 'switches', 'flips' or 'threshold
crossings' take place, and the dynamics of 'resistance
to restoration', two important areas of active study
(Hobbs & Norton 1996) where more research is
urgently needed.
Obviously, we need indicators that are quantifiable,
reliable and transferable, but they also should be
inexpensive and cost-effective, so as not to get left
out of CMR programmes for budgetary reasons.
Moreover, since large numbers of attributes can
rarely be monitored in a single project, it is import-
ant, early on, to identify a compact and affordable
suite of the most pertinent, sensitive and reliable
attributes for each experimental site, gradient or pro-
ject. Ideally, they should be amenable to synchronic
and diachronic comparisons, as mentioned above.
Moreover, we repeat that, in the new paradigms dis-
cussed here, ecological restoration and CMR measures
of diagnosis, evaluation and monitoring must address
not only ecological but also social, political, juridical,
economic and, in some cases, cultural aspects of
ecosystem responses and resilience. They must also be
simple enough to aid in clear communication trans-
fers, and synergy for specific projects, among scient-
ists of different backgrounds and training, and also
the more numerous non-scientists, including eco-
system users, stakeholders, resource and area managers,
industrialists and engineers (see Winterhalder
et al.
2004).
Restoration and
conservation ecology
Fine-tuning
(adjustments)
Monitoring
Diagnosis
CMR projects, including
long-term ecological experiments
Monitoring
Fine-tuning
Ecological engineering
developments
Fig. 17.1
Schematic view of the pathways and
linkages among restoration and conservation ecology
(top), on-going refinement of ecological engineering
methods (bottom) and the central trio of conservation,
management and restoration (CMR) projects and
programmes. Monitoring, diagnosis (assessment)
and managerial fine-tuning represent the modes of
interaction between science and applied enterprises
confronting specific ecological and environmental
problems of all sorts (see also Fig. 16.3).
Eeten and Roe (2002) and other authors point out,
ecological, engineering and resource management
concerns and criteria must all be considered.
Turning now to the related issue of choice and
combination of indicators, we note that there is still
much to do in order to develop, test and validate prac-
tical means and criteria to evaluate success of our
efforts in biological, ecological and socio-ecological,
or human ecology, terms. Aronson
et al.
(1993a) and
Aronson and Le Floc'h (1996a) pointed out that no
single bio-indicator or 'flagship' species can provide
the basis for a full, or reliable, assessment or diag-
nostic evaluation of the status or progress of a
