15.1 Life in the Earth System
KEY CONCEPT
The biosphere is one of Earth’s four interconnected
systems.
15.1 Life in the Earth System
The biosphere is the portion of Earth that is inhabited by
life.
• The biosphere includes all ecosystems.
– one of Earth’s systems
– includes the biota, all the living things in the biosphere
15.1 Life in the Earth System
• There are three other Earth
systems.
– hydrosphere—water, ice,
and water vapor
– atmosphere—air
blanketing Earth’s solid
and liquid surface
– geosphere—geologic
features above and
below Earth’s surface
15.1 Life in the Earth System
Biotic and abiotic factors interact in the biosphere.
• All four Earth systems
are interconnected.
• The Gaia hypothesis
considers Earth as a
kind of living organism.
– Earth systems
interact to yield a
biosphere capable
of supporting life.
– It was developed by
James Lovelock
and Lynn Margulis.