energy flow, trophic efficiency, and trophic levels

Dr. Paul Steiner stated that -

“Studying The Relationship Between Energy And Life Enables Us To Create Informed, Testable Hypotheses About Biological Systems”

Energy

____ is The Foundation Of All Ecosystems

External Energy -

• Enters Ecosystems

• Is Converted To Useful Forms Like Carbohydrates

• Exits Ecosystems

Ecosystem Energy Dynamics Can Inform

The Design Of Conservation Programs

One Direction

Energy Moves Through Ecosystems In ____ ____

Energy Is Not Recycled And Reused Like

Chemicals

Energy Enters At The Primary Producer Level

Feeding Transfers Energy To Each Higher

Trophic Level

• Energy Exits Ecosystems At Each Trophic Level

As Heat

Energy Pyramids Show The Total Energy At

Each Trophic Level

Tropic efficiency

The Percentage (%) Of Energy Transferred

Between Adjacent Trophic Levels Due To

Feeding

•~10% Average For Terrestrial Ecosystems

•~20% Average For Aquatic Ecosystems

o Primary Producers Are More Digestible

And Nutrient-Rich

o Primary Producers Grow And Reproduce

Rapidly

o More Food Is Directed To Consumers Than

Decomposers

Trophic Efficiency

The Ecological Relevance Of ____ ____

It Influences The -

•Amount Of Total Biomass At Each

Trophic Level

•Number Of -

o Individuals At Each Trophic Level

o Trophic Levels In Food Webs

Limit

The Factors That ____ Trophic Efficiency In Ecosystems

Consumers Don’t -

Always Consume The Entire Prey Organism

Eat All The Individuals At Lower Trophic Levels

Some Food Energy Sustains The Existing Cells And Tissues Of Consumers

The Digestion Of Consumed Food Is Incomplete And Inefficient

Decomposition

The Rate Of ____ Influences Trophic Efficiency

This Rate Determines The Availability Of

Chemicals That 10 Producers Need For

Chemosynthesis And Photosynthesis

•This Consequently Affects The Amount

Of Food Energy In The Form Of

Carbohydrates That Enters Ecosystems

Biomagnification

The ____ Of Toxins Reduces Trophic Efficiency

Toxins Reduce Metabolic Efficiency In Consumers

•This Consequently Reduces 20 Production In

Consumers

o This Decreases Food Availability For Consumers

Including Apex Predators

Secondary (20) Production Is The Generation Of

New Biomass By Heterotrophs Including Microbes

Lobster

Would It Be Safer To Consume Lobsters Or Tuna From Aquatic Ecosystems Contaminated With Mercury?

Biomass Pyramids

____ ____ Show Total Biomass At Each Trophic Level

Trophic Efficiency Influences The Total Biomass

At Each Trophic Level

•Biomass Is The Total Mass Of All Species In A

Specific Area Or Volume

Inverted Biomass Pyramids

Some Aquatic Ecosystems Have ____ ____ ____

The Consumers Have -

•More Biomass

•Higher Trophic Efficiencies

•Longer Lifespans

The Phytoplankton (10 Producers) Have -

•Short Lifespans

•Offspring That Are Quickly Consumed

•Rapid Reproductive Rates

Conservation Biology

Trophic Efficiency Is Relevant To ____ ____

 Some Risk Factors For Local Subpopulations

Extinctions Are -

• Reduced Energy Input

• Reduced Trophic Efficiency

 Is There Sufficient Energy In This Aquatic

Ecosystem In This Energy Pyramid To

Support Sustainable Apex Predator

Populations?

The Trophic Structure And Efficiency Of Human Food Webs

The Primary (10) Producers Are Crops

The Primary (10) Consumers Are -

• Livestock

• Wildlife

The Secondary (20) Consumers Are People

Maximizing Trophic Efficiency In Human Food Webs

 Vegetarians (10 Consumers) Have Access To ~10X More Total Food Calories Than Meat Eaters (20

Consumers)