Final answer:
Ecosystems consist of living organisms interacting with non-living factors, including lichens that serve as an early warning system for forest health.
Explanation:
An ecosystem is a unit of nature where all living organisms interact with each other and with non-living factors. The forest ecosystem, for example, includes trees, mosses, microbes, deer, birds, and insects, along with the air, soil, rocks, and sunlight.
By examining the lichen population's health, such as their sensitivity to air pollution, organizations like the U.S. Forest Service can monitor air quality in an area, making them an early warning system for forest health.
The interactions between living organisms and abiotic factors within an ecosystem form a complex web of relationships that contribute to the overall health and functioning of the ecosystem.
Learn more about Ecosystems and Forest Health here:
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