[Academic] Methods of assessing regional ecosystem health (II)

A proposed framework for developing indicators of ecosystem health

This article from SpringerLink give a few principles you must consider when you are assessing regional ecosystem health.

1. Because you are considering health, you should always consider factors concerning human health and well being in the ecosystem;
2. Biogeochemical and socialeconomic factors are influencing each other;
3. Different management goals determined different indicators used;

A holistic approach to ecosystem health assessment using fish population characteristics

This article provided an idea that using some key species as the indicator of region ecosystem health. However, I think it is difficult to apply this method to Fengtai and Fangshan district in my research. I know too little about species and biodiversity in this area and lack knowledge of historical data in this area.
Nor can I identify a key species.