all living and non-living things occurring naturally on Earth or some region thereof
Natural environment means all living and non-living things occurring naturally, meaning not because of humans. The universe is natural, but often the term "natural environment" only means nature on Earth.
Two aspects are usually included::
- Ecological units which are natural systems without much human interference. These include all vegetation, microorganisms, soil, rocks, atmosphere, and natural events.
- Universal natural resources and physical phenomena which lack clear-cut boundaries. These include climate, air, water, energy, radiation, electric charge, and magnetism.