Ecological health
Ecological health is a term that has been used in relation to both human health and the condition of the environment.
- In medicine, ecological health has been used to refer to multiple chemical sensitivity, which results from exposure to synthetic chemicals in the environment, hence the term ecological.
- The term has also been used in medicine with respect to management of environmental factors that may reduce the risk of unhealthy behavior such as smoking.
- As an urban planning term, ecological health refers to the "greenness" of cities, meaning composting, recycling, and energy efficiency.
- With respect to broader environmental issues, ecological health has been defined as "the goal for the condition at a site that is cultivated for crops, managed for tree harvest, stocked for fish, urbanized, or otherwise intensively used."
The term health is intended to evoke human environmental health concerns, which are often closely related. As with ecocide, that term assumes that ecosystems can be said to be alive . While the term integrity or damage seems to take no position on this, it does assume that there is a definition of integrity that can be said to apply to ecosystems. The more political term ecological wisdom refers not only to recognition of a level of health, integrity or potential damage, but also, to a decision to do nothing to harm that ecosystem or its dependents. An ecosystem has a good health if it is capable of self-restoration after suffering external disturbances. This is termed resilience.
Measurements
Measures of broad ecological health, like measures of the more specific principle of biodiversity, tend to be specific to an ecoregion or even to an ecosystem. Measures that depend on biodiversity are valid indicators of ecological health as stability and productivity are two ecological effects of biodiversity. Dependencies between species vary so much as to be difficult to express abstractly. However, there are a few universal symptoms of poor health or damage to system integrity:- The buildup of waste material and the proliferation of simpler life forms that thrive on it - but no consequent population growth in those species that normally prey on them;
- The loss of keystone species, often a top predator, causing smaller carnivores to proliferate, very often overstressing herbivore populations;
- A higher rate of species mortality due to disease rather than predation, climate, or food scarcity;
- The migration of whole species into or out of a region, contrary to established or historical patterns;
- The proliferation of a bioinvader or even a monoculture where previously a more biodiverse species range existed.