Transcript Ecosystem Boundaries - Liberty Union High School District

By 2006, more than 9 million people lived in this small nation,
and less than 2 percent of its land remained forested.
Chapter 3
Ecosystem Ecology
Ecosystem Ecology examines interactions
between the Living and Non-Living world
• Ecosystem - A particular location on Earth
distinguished by its particular mix of
interacting biotic and abiotic components.
Ecosystem Boundaries
don’t need in notes
• Some ecosystems, such as a caves and lakes have very
distinctive boundaries. However, in most ecosystems it is
difficult to determine where one ecosystems stops and the next
begins.
Section 2: Energy Flows through Ecosystems
Producers (autotrophs) are able to use the
sun’s energy to produce usable energy
through the process called photosynthesis.
Section 2: Energy Flows through Ecosystems
• Cellular respiration is the process by which other
organisms gain energy from eating the tissues of
producers.
“Trophic” Energy Pyramid
Decreases by 10% with each higher level
The representation of the distribution of biomass among trophic levels.
Ecological efficiency- The proportion of consumed energy
that can be passed from one trophic level to another.
Calories
don’t need in notes
The energy needed to raise the temperature of 1 gram of water through 1 °C
Trophic pyramid
(don’t need in notes)
This trophic pyramid
represents the amount
of energy that is present
at each trophic level,
measured in joules (J).
One joule is equal to the energy used to accelerate a body with a mass
of one kilogram using one newton of force over a distance of one meter.
While this pyramid assumes 10 percent ecological efficiency, actual
ecological efficiencies range from 5 to 20 percent across different
ecosystems. For most ecosystems, graphing the numbers of individuals
or biomass within each trophic level would produce a similar pyramid.
(page 39)
• Food Chain:
The sequence of
consumption from
producers through
tertiary consumers.
vs.
• Food Web:
A more realistic type
of food chain that
takes into account the
complexity of nature.
Ecosystem Productivity
• Gross primary
productivity (GPP)
The total amount of solar
energy that the producers in
an ecosystem capture via
photosynthesis over a given
amount of time.
• Net primary
productivity (NPP)
The energy captured (GPP)
minus the energy respired
(lost) by producers.