p.1 The idea to apply an assessment of ecosystem health to environmental management emerged
in the late 1980s. [JLJ - Ok, what if we apply an assessment of "health" of a game position to search focus and steering search
efforts in a game? ]
p.1 If we observe that an ecosystem is not healthy, we want a diagnosis. What is wrong? What caused
this unhealthy condition? What can we do to bring the ecosystem back to normal? To answer these
questions, and also come up with a cure, ecological indicators are applied.
p.1-2 Of course there are general ecological indicators that are used almost every time we have
to assess ecological health; but they are never sufficient to present a complete diagnosis - the general indicators
always have to be supplemented by other indicators.
p.6 Costanza summarizes the concept definition of ecosystem health as:2
1. Homeostasis
2. Absence of disease
3. Diversity or complexity
4. Stability or resilience
5. Vigor or scope for growth
6. Balance between system components.
He emphasizes that it is necessary to consider all or [at] least most of the definitions simultaneously.
Consequently, he proposes an overall system health index, HI = V x O x R, where V is system vigor, O is the
system organization index and R is the resilience index. With this proposal, Costanza touches on probably the most crucial
ecosystem properties to cover ecosystem health.
p.34 We must accept the complication that ecosystems are dynamic systems and will never attain equilibrium.
We therefore need to apply dynamic models as widely as possible and it can easily be shown that dynamic models give
results other than static ones.
p.278 the high complexity of ecological systems has not only become an accepted fact, but also an interesting
object of investigation. In parallel, a successful reductionistic methodology has been accomplished steadily by holistic
concepts which stress systems approaches and syntheses, and which elucidate the linkages between the multiple compartments
of ecological and human-environmental systems within structural, functional, and organizational entities.
p.280 three principle pillars have been considered as basic conceptual "points of departure" for indicator
derivation.
The first guideline... ecosystems are comprehended as self-organizing entities,
and the degree of self-organizing processes and their effects have been chosen as an aggregated measure to represent the systems'
actual states... A second pillar is built up by the methodologies of ecosystem analysis: to depict ecological entities
in a holistic manner, structure as well as function has to be taken into account... Finally... a useful indicator
set has to be based on... a specific definition of ecological integrity... which includes several items that are
valid for the ecosystem health approach as well.
p.280 the ecosystem health concept... stresses the creativity of nature, which is
nothing else than the potential for self-organization.
p.281 Self-organized systems are capable of creating structures and gradients if they receive a
throughflow of exergy (usable energy, or the energy fraction of a system which can be transferred
into mechanical work, see Jorgensen 2000).
