Environmental Engineering Reference
In-Depth Information
a little counterintuitive, it is something that already happens (albeit without
the outcome being framed in 'quality' terms) in management: for example,
domestic water supply management involves both increase of supply and
regulation of demand.
A third feature that emerges from such a definition of quality is that it is not
absolute. There is no single target for what constitutes good quality, but
existing targets can be incorporated into it: if there is a strong demand for
features of a natural riverine environment, for example, as a component of the
recreational, conservation or aesthetic services a system provides then that
becomes one of the criteria on which the quality of the systemmight fall down.
Constructing an ESP and its use in environmental management
There are clearly a number of stages involved in generating such a service
profile and the challenges at each stage are significant.
First of all, some set of services must be defined, which are appropriate to the
system (e.g., in the case of a river, fish production for angling, flood mitigation,
water supply and aspects of biological conservation might all feature). Whilst
in some cases the list may be fairly obvious, we do not underestimate the
practical difficulty of generating an agreed list appropriate to a system. This
might have to be based on standard 'core' lists defined for particular types of
system, or derived on a system-by-system basis. Stakeholder involvement is
probably useful but one important issue is that attention should be given to
services which might not naturally have a high 'visibility' in the current state
of the system, but have the potential to be important. Again, flood regulation
would be a good example: if flood regulation is currently provided very effect-
ively by a system, its consequence lack of serious flooding may mean that
most people do not realise is it a function delivered by the current system, so
might not identify it as a service they 'use'.
The next stage of the process would be to identify indicators for the services.
This is necessary (a) because many services cannot easily be measured directly,
and (b) because it will be necessary to work with data that are already available,
or can be readily generated. So, for example, the extent of flood regulation in
essence the extent to which flooding has not happened is hard to assess
directly, but it may be more practical to assess related variables such as
predicted maximum water retention capacity given land use and floodplain
capacity in the area. Similar issues arise with measuring sustainable provision
an indirect approach may be needed. The constraints of data availability are
also significant since practical use of such a measure would not easily accom-
modate the time and cost involved in detailed long-term data gathering.
However, these issues apply to many current management scenarios, and the
use of indicators is already established in a number of areas, such as biodiver-
sity conservation (Karr
1999
; Scholes & Biggs
2005
).
