Maintaining Biodiversity

Maintaining Biodiversity

Middle School

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Learning Objectives

• Describe how population growth and resource use affect Earth's systems and biodiversity.

• Identify five major threats to biodiversity, such as habitat loss and invasive species.

• Compare proactive and reactive solutions for protecting biodiversity.

• Explain how models and testing help create the best environmental solutions.

Key Vocabulary

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Biodiversity

The variety of life in a particular habitat or ecosystem, including all plants, animals, and microorganisms.

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Habitat Destruction

The process of damaging a natural habitat, which prevents it from supporting the species that live there.

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Invasive Species

A non-native organism that gets introduced to an ecosystem and causes harm to the local environment.

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Overexploitation

The action of using a species at a rate that is faster than its natural population can recover.

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Pollution

The introduction of harmful substances or contaminants into the natural environment, which causes negative effects or harm.

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Climate Change

Refers to long-term shifts in temperatures and weather patterns, largely driven by various human activities.

Key Vocabulary

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Per-capita Consumption

Per-capita consumption refers to the average amount of a resource that is used by one person.

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Natural Resources

These are valuable materials from the Earth that support life and meet the needs of people.

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Earth Systems

Earth's systems are its interacting physical, chemical, and biological processes that work together as a whole.

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Engineered Solution

An engineered solution is a piece of technology or a process designed to solve a specific problem.

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Iterative Testing

This is a repeating, cyclical process of designing, testing, and refining a solution to improve it.

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Model

A model is a simplified representation of a real-world object or process, used to test ideas.

Human Population and Resource Use

• A growing human population increases the demand for natural resources.

• Each person using more resources places significant stress on Earth's systems.

• This leads to growing negative impacts on the environment and biodiversity.

Multiple Choice

What is a primary consequence of a growing human population?

• An increased demand for natural resources.

• A decrease in the use of resources.

• A positive impact on the environment.

• An immediate increase in biodiversity.

Multiple Choice

How does a high level of resource consumption by humans affect Earth's systems?

• It helps to restore and improve natural habitats.

• It has no significant effect on Earth's systems.

• It places significant stress on the environment and biodiversity.

• It leads to a decrease in the demand for resources.

Multiple Choice

What is the most likely long-term outcome if a large population not only continues to grow but also increases its rate of resource use per person?

• The environment would adapt and create more resources.

• A continued decline in biodiversity and environmental health.

• The population would naturally decrease its resource use.

• A significant improvement in the health of Earth's systems.

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Major Threats to Biodiversity

• Habitat destruction is when an environment is changed so organisms can’t live there.

• Pollution contaminates the environment with harmful substances like oil spills or smoke.

• Overexploitation is the overuse of species for human needs, such as overfishing.

• Climate change refers to long-term shifts in Earth’s climate, including global warming.

• Invasive species are non-native organisms that can outcompete and harm native life.

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Multiple Choice

Which of the following best defines overexploitation?

• The overuse of species for human needs, such as overfishing.

• When an environment is changed so organisms can't live there.

• When non-native organisms outcompete and harm native life.

• The contamination of the environment with harmful substances.

Multiple Choice

A forest is cut down to build a shopping mall, and a non-native vine spreads through another forest, blocking sunlight from reaching the trees. How are these two situations similar in the way they threaten biodiversity?

• Both events lead to the loss of a place for native organisms to live.

• Both events are caused by long-term shifts in Earth's climate.

• Both events involve the contamination of the environment by harmful substances.

• Both events are examples of non-native organisms harming native life.

Multiple Choice

Rising ocean temperatures are damaging coral reefs where many fish live. In the same area, an oil spill has occurred. What is the most likely combined effect of these two threats on the local fish?

• The fish population will likely decline due to both the loss of their home and contamination of their water.

• The warmer water will help the fish population grow, counteracting the effects of the oil spill.

• The oil spill will eliminate all invasive species, which will help the native fish.

• The main threat will be overexploitation as people try to catch the remaining fish.

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Understanding Invasive Species

• An invasive species is an organism introduced to an ecosystem where it doesn't belong.

• They outcompete native species for resources like food, space, and nutrients.

• The Kudzu vine, for example, overgrows and blocks sunlight from native plants.

• Some invasive plants can even change soil composition, harming native species.

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Multiple Choice

What is the definition of an invasive species?

• An organism introduced to an ecosystem where it does not naturally live.

• A native species that is struggling to survive in its habitat.

• Any plant or animal that is larger than others in its ecosystem.

• An organism that helps native species by providing new food sources.

Multiple Choice

How do invasive species typically harm native species in an ecosystem?

• They take away resources like food and space that native species need.

• They provide a new source of food for native predators.

• They make the ecosystem more diverse and stable.

• They are unable to adapt to new environments.

Multiple Choice

If a new, non-native vine that grows very quickly and covers the tops of trees is introduced to a forest, what is the most likely impact on the smaller native plants below?

• The native plants will be unable to get enough sunlight to grow.

• The native plants will have more nutrients available in the soil.

• The native plants will start to grow on top of the new vine.

• The native plants will be better protected from the wind.

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Solutions for Protecting Biodiversity

Proactive Methods

• Proactive methods aim to stop invasive species from entering a new area in the first place.

• Border protection stations that inspect cars are an example of a proactive method.

• Reusing materials also protects biodiversity by reducing the need to extract new natural resources.

Reactive Methods

• Reactive methods are used to remove an invasive species after it has already arrived.

• An effective reactive method is biological control, which uses an invasive species' natural predators.

• For example, releasing beetles that only eat the invasive purple loosestrife plant.

Multiple Choice

What is the main difference between proactive and reactive methods for protecting biodiversity?

• Proactive methods are used before a species invades, while reactive methods are used after.

• Proactive methods involve natural predators, while reactive methods involve border stations.

• Proactive methods are for plants, while reactive methods are for animals.

• Proactive methods reduce resource extraction, while reactive methods increase it.

Multiple Choice

How does reusing materials help protect biodiversity?

• It reduces the need to extract new natural resources from habitats.

• It provides more food for native animal populations.

• It stops invasive species from being transported in cars.

• It helps fund biological control programs for invasive species.

Multiple Choice

An invasive plant species has started to spread rapidly through a forest, crowding out native plants. Based on the methods described, what would be the most effective solution to this existing problem?

• Introduce a natural predator that specifically targets the invasive plant.

• Set up inspection stations to check cars for the plant's seeds.

• Start a campaign to reuse and recycle materials in the area.

• Plant more native trees to compete with the invasive plant for sunlight.

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Developing and Testing Solutions

• Effective solutions are improved through a cycle of testing, analysis, and modification.

• This process is called iterative testing and helps refine the solution.

• Scientists use models, like simulations or small-scale versions, for testing.

• The goal is an optimal solution that meets criteria within all constraints.

Multiple Choice

What is the name of the process where a solution is improved through a cycle of testing, analysis, and modification?

• Iterative testing

• Finalizing a design

• Scientific modeling

• Creating constraints

Multiple Choice

What is the primary function of using models, like simulations or small-scale versions, in the design process?

• To test how a solution works before building a final version

• Because models are always better than the real-world solution

• To create the list of criteria and constraints for the project

• Because a final solution is not the main goal of the process

Multiple Choice

A team builds a model boat designed to hold a specific weight, but it sinks during a test. What is the most logical next step in their process?

• Analyze the test results and modify the design to better meet the criteria.

• Decide that the solution has failed and abandon the project.

• Present the current design as the optimal solution.

• Ignore the constraints and build a much larger, more expensive version.

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Common Misconceptions

Misconception	Correction
A non-native species is always invasive.	A non-native species is invasive only if it causes harm.
All human impact on the environment is negative.	Engineered solutions can help reduce harmful human impacts.
Once a solution is designed, it is ready to use.	Solutions need lots of testing and changes to be effective.
You can remove an invasive plant just by cutting it down.	Many invasive plants regrow from small pieces of root, making removal difficult.

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Summary

• Human population growth and consumption are major drivers of environmental impact.

• Key threats to biodiversity include habitat destruction, pollution, and overexploitation.

• Solutions to reduce human impact can be proactive, reactive, or engineered.

• Effective solutions are developed through an iterative process of testing and modification.

Poll

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

• 1

• 2

• 3

• 4