I have mentioned the ongoing struggle to define what makes for a good ecosystem before. The easiest example are historical goals for natural environments, “economic productivity” followed by “pristineness” which have now been improved to things like “ecosystem functions” and “biodiversity.” I am a proponent of taking this further, to include things like “interelationships,” “phylogenetic diversity,” “complexity,” and “ecological diversity.” While abandoning goals like “nativeness” and possibly even certain kinds of “naturalness.”
All attempts to define “healthy” in the conext of natural ecosystems have exceptions.
- Growth is good except when its algae slime in eutrophication.
- Biodiversity is good except when its common species instead of rare desert/alpine species.
- Toxins are bad except when its a special halophilic or serpentine environment.
- Natural diasasters are bad except when its a fire-adapted or typhoon-adapted ecosystem.
So any definition is going to be a whole lot of caveating.
Here is my current thinking around this: