How is everything on our
planet interconnected?
Layers of Our Planet
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Geosphere: solid part
of earth that consists
of soil, rock and
sediments.
Atmosphere: mixture
of gases surrounding
earth.
Hydrosphere: All
water found on earth.
Biosphere: All areas
on the planet that life
can exist.
How Does Energy Flow Through
an Ecosystem?
FOOD CHAIN
FOOD WEB
ENERGY PYRAMID
Why Does Energy Decrease at
Higher Trophic Levels?
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Some of the energy
is used for
organism’s growth.
Lost through heat
(entropy)
Fecal Waste
What Are Biomes?
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A large region of the planet characterized by
a specific climate and certain types of plants
and animal communities.
Depends on Temperature & Rainfall
(climate)
How do we measure an
ecosystem’s productivity?
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GPP (Gross Primary Productivity): Rate at which an ecosystem’s
producers convert solar energy into chemical energy as biomass
(cells, leaves, roots and stems)
NPP (Net Primary Productivity) = GPP – Rate at which producers
use chemical energy
Most Productive Ecosystems
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Least Productive Ecosystems
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Estuaries
Wetlands (swamps and marshes)
Rainforest
Open oceans*
Tundra
Desert
* However the planet has so much open ocean that it produces
more of Earth’s NPP than any other ecosystem!
Net Primary Productivity (NPP)
How Do Ecosystems Change?
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Ecological Succession:
gradual change and
replacement of species in a
community.
Primary Succession:
occurs on a surface where
no ecosystem existed
before.
Secondary Succession:
occurs where an
ecosystem already existed
(disrupted by humans,
animals, storms)