Environmental Engineering Reference
In-Depth Information
Conclusions
The ecosystem services that deliver support for the basic requirements of
human life, and the wherewithal for the development of the complex indus-
trial, and post-industrial societies we live in, are threatened by the demands
we make on them. In seeking to manage these demands, we need quality
criteria that take account of the fact that return of most ecosystems to
pre-industrial, or pre-human states
is not a practical, or necessarily
desirable, goal.
The proposed framework for ecological quality assessments based on ecosys-
tem services, unlike traditional approaches (e.g., general water quality stand-
ards), accounts for the fact that the value put on the state of a system will
depend on the specific management context (land use, population density etc.)
and associated societal demands. For instance, in catchments of low popula-
tion density and land use intensity, conservation of biodiversity and aesthe-
tical enjoyment might be primarily valued, whereas in urban dominated
catchments the supply of drinking water, flood mitigation and attenuation
of pollutants are likely to be highly desired ecosystem services. If the
demand supply balance is periodically reviewed, it also allows for changes
over time, either through changes in societal demand and expectation, or
changes in external drivers of function such as climate. By incorporating
a suite of services, and their interdependencies, demand for one service has
to take into account not just the provision of that service, but the effect of
provision at that level on others where the services may include supporting,
provisioning, regulating and cultural services.
At the level we have outlined here, the ESP concept provides a framework for
ecological quality assessments. There are significant research challenges ahead
before we could actually apply the concept in practice, but our aim here is to
stimulate critical debate about the idea. We suggest that the ESP framework
provides an adaptable and robust approach, which has the potential to foster a
more integrative approach to ecosystem assessment and management in the
future, and to meet the broad challenges laid down by new and forthcoming
environmental legislation.
Whereas the focus of environmental management tends to be local, regional
or national, ecosystem services are traded globally. The decline in heavy indus-
try in many developed countries has generally been associated with an
improvement in environmental quality, hence addressing the desire of such
societies for minimally impacted environments. However, societies in
developed countries have a high demand for industrial products and meet this
demand by importing ecosystem services and the products derived from them,
often from countries where environmental legislation and management is less
well-developed and enforced. Importing ecosystem services, or the products
derived from them, does not mitigate the environmental impact of their
