Biodiversity in Ecosystems

Biodiversity in Ecosystems

Middle School

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Learning Objectives

• Define biodiversity and explain its importance for keeping ecosystems strong and balanced.

• Analyze how the availability of resources affects organisms and their populations.

• Describe how energy and matter move through producers, consumers, and decomposers.

• Identify the main threats to biodiversity and ways we can help protect it.

Key Vocabulary

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Biodiversity

Biodiversity refers to the wide variety of different plants, animals, and other living organisms in a particular region.

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Species

A species is a group of similar organisms that can reproduce with each other to create fertile offspring.

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Ecosystem

An ecosystem includes all the living organisms in a community and their non-living physical environment interacting together.

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Biome

A biome is a very large geographical area characterized by its specific climate, plants, and animal life.

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Resource Availability

Resource availability is the access organisms have to essential resources like food, water, sunlight, and living space.

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Competition

Competition is the struggle between organisms for the same limited resources, such as food, water, or territory.

Key Vocabulary

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Producer

A producer is a living thing, such as a plant, that creates its own food.

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Consumer

A consumer is an organism that gets its energy by eating other living things.

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Decomposer

A decomposer breaks down dead plants and animals, returning nutrients to the soil.

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Food Web

A food web is a model that shows how energy moves through an ecosystem.

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Matter Cycling

Matter cycling is the process where atoms are reused within an ecosystem over time.

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Energy Flow

Energy flow shows the one-way transfer of energy from the sun to ecosystem organisms.

What is Biodiversity?

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Genetic Diversity

• This refers to the variety of genes within a single species.

• It includes inherited traits like different eye colors and hair textures.

• This genetic variety helps populations adapt to environmental changes.

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Species Diversity

• This is the number of different species in an ecological community.

• It also includes the quantity of each species in that community.

• A forest with many types of trees has high species diversity.

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Ecosystem Diversity

• This is the variety of different ecosystems found in the biosphere.

• Each ecosystem has unique factors that support different forms of life.

• Examples include deserts, lush rainforests, and vibrant coral reefs.

Multiple Choice

Which of the following best defines genetic diversity?

• The variety of genes within a single species.

• The number of different species in a community.

• The variety of different ecosystems in the biosphere.

• The unique factors that support different forms of life.

Multiple Choice

How does species diversity differ from ecosystem diversity?

• Species diversity is about the number of species in one community, while ecosystem diversity is about the variety of entire ecosystems.

• Species diversity involves inherited traits like eye color, while ecosystem diversity involves deserts and rainforests.

• Species diversity helps populations adapt, while ecosystem diversity is about the quantity of each species.

• Species diversity refers to a single species, while ecosystem diversity refers to a single community.

Multiple Choice

A population of oak trees faces a new fungal disease. Which statement best explains why high genetic diversity would help the population survive?

• The variety of genes increases the chance that some trees have traits to resist the disease.

• It would allow the oak trees to move to a different ecosystem, like a desert.

• It would increase the number of other tree species in the forest to help the oaks.

• It ensures that all the oak trees are identical and can fight the disease together.

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Resource Availability and Competition

Abundant Resources

• ​Organisms rely on resources like food, water, oxygen, and space to survive.

• ​​With abundant resources, individual organisms grow larger and populations can expand successfully.

• ​The availability of these resources helps support a healthy and thriving ecosystem.

Limited Resources

• ​When resources become scarce, organisms must compete with one another for survival.

• ​​This competition for limited resources restricts the overall growth of a population.

• ​It can also reduce reproduction rates, as there isn't enough to go around.

Multiple Choice

What is the direct result of resources like food, water, and space becoming scarce?

• The ecosystem becomes healthier and more stable.

• Organisms must compete with one another for survival.

• Individual organisms grow larger and reproduce more.

• Populations of all organisms expand successfully.

Multiple Choice

What is the relationship between resource availability and population growth?

• Abundant resources lead to population growth, while limited resources restrict it.

• Resource availability only affects the size of individual organisms, not the population.

• Limited resources cause organisms to reproduce more quickly.

• Both abundant and limited resources cause populations to shrink over time.

Multiple Choice

A healthy ecosystem with a thriving animal population experiences a sudden, severe drought that reduces the water supply. What is the most likely outcome for this population?

• The population will continue to grow at a faster rate.

• The organisms will learn to live without the limited resources.

• Competition will increase, restricting population growth and reproduction.

• The ecosystem will create more resources to support the population.

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Energy Flow in Ecosystems

• In an ecosystem, energy flows in a single, one-way direction, starting from the sun.

• Producers, like plants, make their own food using the sun's energy through photosynthesis.

• Consumers are organisms that get energy by eating producers or other consumers.

• Much of this energy is lost as heat when it is transferred.

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Multiple Choice

Which statement best describes the flow of energy in an ecosystem?

• It flows in a single, one-way direction.

• It cycles back to the producers from the consumers.

• It is created by consumers and then used by producers.

• It flows equally to all organisms at the same time.

Multiple Choice

What is the main difference between how producers and consumers obtain energy?

• Producers get energy from the sun, while consumers get energy from heat.

• Producers make their own food, while consumers get energy by eating other organisms.

• Producers eat other organisms, while consumers make their own food.

• Producers and consumers both get their energy directly from the sun.

Multiple Choice

Given that energy is lost as heat at each transfer, what can be concluded about the energy available to a consumer?

• They have more energy than any other organism.

• There is less energy available to them compared to producers.

• They lose less energy to heat than other organisms.

• They can also get energy from the sun through photosynthesis.

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Matter Cycling in Ecosystems

• Unlike the one-way flow of energy, matter in an ecosystem is cycled.

• ​Decomposers like bacteria and fungi break down the tissues of dead organisms.

• This decomposition releases nutrients from dead organisms back into the environment.

• This shows matter is conserved, meaning it is never created or destroyed.

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Multiple Choice

How does the movement of matter in an ecosystem primarily differ from the movement of energy?

• Matter is cycled, while energy flows in one direction.

• Energy is cycled, while matter flows in one direction.

• Both matter and energy are cycled through an ecosystem.

• Both matter and energy are lost as they move through an ecosystem.

Multiple Choice

What is the main function of decomposers, such as bacteria and fungi, in an ecosystem?

• They break down dead organisms to release nutrients back into the environment.

• They create new energy for the ecosystem by consuming dead organisms.

• They absorb nutrients from the sun to pass on to living organisms.

• They prevent matter from being conserved in the ecosystem.

Multiple Choice

Based on the principle of matter conservation, what would most likely happen if all decomposers were removed from an ecosystem?

• Matter would be trapped in dead organisms and would not be recycled.

• The ecosystem would create new matter to replace the old.

• Matter would be destroyed and disappear from the ecosystem.

• Energy would be converted into matter to keep the cycle going.

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What Is a Food Web?

• A food web models how energy and matter move through an ecosystem.

• It is made of many interconnected food chains, showing complex feeding relationships.

• It shows the roles of producers, consumers, and decomposers.

• Arrows point in the direction that the energy flows.

Multiple Choice

What is the primary purpose of a food web?

• To model how energy and matter move through an ecosystem

• To list all the different species living in a habitat

• To show the life cycle of a single organism

• To track how many individual animals are in an area

Multiple Choice

In a food web diagram, what is the function of the arrows?

• The direction that energy flows between organisms

• The path an animal takes to hunt for food

• Which organisms are producers and which are consumers

• The way matter is created by decomposers

Multiple Choice

If a disease eliminated a producer population, what conclusion is supported by the information about food webs?

• Only the primary consumers that eat the producers would be affected.

• The entire food web would be affected because of the interconnected feeding relationships.

• The decomposers would eventually become producers.

• There would be no major effect, as consumers would find other things to eat.

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Why is Biodiversity Important?

• An ecosystem with high biodiversity is both healthier and more stable.

• Dynamic equilibrium is the term used to describe a stable ecosystem.

• Resilience is an ecosystem's ability to maintain balance despite significant disturbances.

• High biodiversity makes an ecosystem more resilient to challenges like diseases.

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Multiple Choice

What is the primary benefit of high biodiversity for an ecosystem?

• It makes the ecosystem healthier and more stable.

• It causes more frequent and severe disturbances.

• It reduces the total number of organisms in the ecosystem.

• It prevents the ecosystem from experiencing any changes.

Multiple Choice

Which statement best describes what 'resilience' means for an ecosystem?

• An ecosystem's ability to maintain balance when faced with challenges.

• The number of different species living within an ecosystem.

• A state where an ecosystem has very few types of animals.

• The process of an ecosystem becoming less stable over time.

Multiple Choice

A forest with many different types of plants and animals experiences a severe drought. A nearby cornfield, with very few species, experiences the same drought. What is the most likely outcome?

• The forest with high biodiversity would likely be more resilient and recover more easily.

• The field with low biodiversity would be more stable because it is simpler.

• Both ecosystems would be unable to recover from the drought.

• The drought would have no effect on either ecosystem.

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Ecosystem Services: Our Natural Benefits

• Supporting services are foundational processes like nutrient cycling and primary production.

• Provisioning services are products from ecosystems like food, fresh water, and medicine.

• Regulating services are benefits from processes like pollination and climate regulation.

• Cultural services provide nonmaterial benefits like recreation and spiritual enrichment.

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Multiple Choice

Which statement best defines the concept of 'ecosystem services'?

• Services provided by one human to another.

• Benefits that humans receive from natural processes and ecosystems.

• The process of creating man-made parks and gardens.

• The economic cost of managing natural resources.

Multiple Choice

How are provisioning services different from cultural services?

• Provisioning services provide physical products, while cultural services provide nonmaterial experiences.

• Provisioning services are about processes like pollination, while cultural services are about products like food.

• Provisioning services are foundational, while cultural services regulate the climate.

• Provisioning services offer recreation, while cultural services provide fresh water.

Multiple Choice

A coastal mangrove forest is a habitat where nutrient cycling occurs, it protects the shore from storm surges, and is a popular spot for photography. Which combination of ecosystem services does this forest provide?

• Provisioning, supporting, and cultural services

• Regulating, provisioning, and supporting services

• Supporting, regulating, and cultural services

• Cultural, provisioning, and regulating services

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Common Misconceptions

Misconception	Correction
The extinction of one or two species in a large ecosystem doesn't matter.	Every species has a role. Losing even one can disrupt the food web.
Animals can just move to a new habitat if theirs is destroyed.	Many species are highly adapted to a specific habitat and cannot survive elsewhere.
All non-native species are invasive.	A species is only invasive if it causes harm by outcompeting native species.
Energy and matter are the same.	Energy flows one-way through an ecosystem, while matter is cycled continuously.
Ecosystems are static and unchanging.	Healthy ecosystems are in a state of dynamic equilibrium, always changing and adjusting.

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Summary

• Biodiversity is key to a healthy, resilient ecosystem.

• Energy flows one-way, while matter is constantly cycled.

• Human activities threaten the biodiversity that we depend on.

• We can protect biodiversity through restoration and sustainable practices.

Poll

On a scale of 1-4, how confident are you about the concepts covered in today's review?

• 1 (Not confident)

• 2 (A little confident)

• 3 (Mostly confident)

• 4 (Very confident)