An ecosystem is a group of biological communities in a shared physical environment. Air, land, water, and living organisms, including humans, interact to form an ecosystem.
Ecosystems occur at various scales.
The entire earth and all the biological communities it houses is an ecosystem. In practical terms, ecosystems are defined to suit the purpose at hand. Regional Ecosystems Prairie and Northern Region has studied the influence of human activities on the region's major ecosystems and has identified a number of concerns that are helping to guide departmental actions. The region is dedicated to ensuring the environmental health and integrity of these ecosystems.