MS-LS2-5: Maintaining Biodiversity and Ecosystem

MS-LS2-5
Maintaining Biodiversity and Ecosystem

Middle School

​

Learning Objectives

• Define biodiversity and its importance for a stable ecosystem.

• Identify major threats to biodiversity caused by human activities.

• Analyze the role of keystone species in maintaining ecosystem stability.

Key Vocabulary

​

Biodiversity

Biodiversity refers to the wide variety of plants, animals, and other living things in an area.

​

Keystone Species

A keystone species is an organism that plays a crucial role in maintaining its ecosystem's structure.

​

Ecosystem Engineers

These are species that actively modify their environment, creating or changing habitats for other organisms.

​

Extinction

Extinction is the complete and permanent disappearance of a species from Earth, with no surviving individuals.

​

Invasive Species

An invasive species is a non-native organism that causes harm to the local environment or economy.

​

Habitat Loss

Habitat loss is the process where a natural habitat becomes unable to support the species living there.

Key Vocabulary

​

Ecosystem Services

These are the many different kinds of benefits that humans get from various ecosystems.

​

Nutrient Recycling

This is the natural process of moving and reusing essential nutrients within an ecosystem.

​

Soil Erosion

This is the process where the valuable top layer of soil is worn away.

​

​

What Is Biodiversity?

• Biodiversity is the variety of all life in an area, like a pond.

• It can be studied on a small scale or a massive one, like Earth.

• A pond has visible life like turtles, and microscopic life like bacteria.

• All organisms are interdependent, so losing one species affects many others.

​

Multiple Choice

What is the best definition of biodiversity?

• The variety of all life within a specific area

• The study of only microscopic life like bacteria

• The total number of a single species, like turtles

• The interaction between non-living things in an environment

Multiple Choice

Which statement best describes the scope of biodiversity in an area like a pond?

• It can only be studied on a massive scale like the entire Earth

• It is limited to the study of visible life forms like plants and animals

• It includes everything from microscopic bacteria to large animals

• It focuses only on the relationships between different species

Multiple Choice

Based on the concept of interdependence, what is the most likely outcome if a key species is removed from an ecosystem?

• The loss of one species can negatively impact other organisms

• The biodiversity of the area will likely increase

• Only organisms of the same size will be affected

• The remaining organisms will not be affected in any way

​

​

Distribution and Importance of Biodiversity

• Scientists use sampling to calculate a biodiversity index, measuring ecosystem health.

• Biodiversity is greatest near the equator due to its warm and wet climate.

• This climate provides the stable supply of energy and water that life needs.

• High biodiversity makes ecosystems more resilient and able to recover from disasters.

​

Multiple Choice

What is a primary benefit of high biodiversity in an ecosystem?

• It causes the climate to become warmer and wetter.

• It allows the ecosystem to be more resilient to disasters.

• It prevents scientists from needing to sample the area.

• It decreases the total amount of energy and water available.

Multiple Choice

What is the relationship between the climate near the equator and its high biodiversity?

• The area is less prone to natural disasters.

• The stable, warm, and wet climate provides the necessary energy and water for life.

• Scientists have conducted more sampling in that specific region.

• The ecosystems there have lower resilience and need more species.

Multiple Choice

A scientist finds that Ecosystem X has a very high biodiversity index, while Ecosystem Y has a very low one. If a wildfire affects both areas, what is the most likely prediction?

• Ecosystem Y will recover more quickly because it has lower biodiversity.

• Ecosystem X will likely recover more quickly because its higher biodiversity makes it more resilient.

• Both ecosystems will recover at the same rate because the disaster was the same.

• Neither ecosystem will be able to recover from such a major disaster.

What Are Ecosystem Services?

​

Water Purification

• Wetlands act as natural filters for our water supply.

• They remove pollutants and harmful contaminants from the water.

• This process provides us with clean and safe drinking water.

​

Nutrient Recycling

• Decomposers break down dead organic matter like fallen leaves.

• This process returns vital nutrients back into the soil.

• Healthy soil is then able to support new plant growth.

​

Soil Erosion Prevention

• Plant roots securely hold soil particles together in one place.

• This prevents wind and water from washing the soil away.

• Protecting our soil is essential for farming and construction.

Multiple Choice

Which statement best describes the overall purpose of ecosystem services?

• They are natural processes that are beneficial to the environment and people.

• They are services created by humans to clean up pollution.

• They are processes that only benefit the plants in an ecosystem.

• They are harmful processes that damage the environment over time.

Multiple Choice

How does the breakdown of dead organic matter by decomposers support an ecosystem?

• It filters pollutants and contaminants from the water supply.

• It returns essential nutrients to the soil, which helps new plants grow.

• It holds soil particles together to prevent them from washing away.

• It provides a source of food for large animals in the ecosystem.

Multiple Choice

If a large number of trees and wetland plants were removed from an area near a river, what would be the most likely outcome?

• The soil would become more nutrient-rich for farming.

• Water quality would decrease, and soil erosion would increase.

• The amount of clean drinking water would increase.

• New plant growth in the area would be better supported.

​

​

Stability and Change in Ecosystems

• Small changes in an ecosystem can cause much larger changes.

• This is especially true when a keystone species is affected.

• Removing wolves leads to a large increase in the deer population.

• More deer eat too many plants, leading to soil erosion.

​

Multiple Choice

What is the main principle concerning change in an ecosystem?

• Small changes within an ecosystem can result in much larger consequences.

• Ecosystems are always stable and do not change over time.

• Only the removal of plants can cause large changes in an ecosystem.

• Changes to a keystone species only affect other animal populations.

Multiple Choice

What is the direct relationship between wolves and deer in this ecosystem?

• The removal of wolves allows the deer population to increase significantly.

• The presence of wolves helps the deer population find more food.

• The removal of wolves leads to a decrease in the deer population.

• The presence of wolves has no direct effect on the deer population.

Multiple Choice

Which statement best explains how the removal of a keystone species like the wolf can lead to soil erosion?

• An increase in deer leads to overeating of plants, which causes the soil to wash away.

• The wolves were directly protecting the soil from eroding.

• A larger deer population packs the soil down, preventing erosion.

• The loss of wolves means there is more water available for plants.

​

​

Human Impact on Biodiversity

• The greatest threat is extinction, caused by humans in the Anthropocene era.

• Habitat loss from deforestation, farming, and construction is a primary extinction driver.

• Overhunting, overfishing, and the introduction of invasive species harm native populations.

• Pollution and climate change alter environments, making habitats unsuitable for life.

​

Multiple Choice

What is the greatest threat to biodiversity resulting from human activity in the Anthropocene era?

• The permanent loss of species from Earth.

• The process of creating new farms for crops.

• The introduction of new animals to an area.

• The gradual warming of the planet's climate.

Multiple Choice

How do activities like deforestation, farming, and construction primarily drive extinction?

• They create new sources of food for all animals.

• They help native species compete with new species.

• They destroy the natural environments that species need to survive.

• They reduce the amount of pollution in the air and water.

Multiple Choice

If a large area of forest is cleared for a new housing development and a non-native plant is introduced for landscaping, what is the most likely long-term consequence for native wildlife?

• The native species will quickly adapt to the new environment and thrive.

• The new species will be unable to survive in the altered habitat.

• The native species may face extinction due to habitat loss and competition from the new species.

• The forest ecosystem will become more stable and diverse.

​

Common Misconceptions

Misconception	Correction
All species in an ecosystem are equally important.	Keystone species have a much larger impact on the ecosystem.
Extinction is a natural event that only happened in the past.	A new mass extinction is currently happening due to human activities.
The most advanced environmental solution is always the best one.	The best solution balances science, cost, and social factors.
Small, individual actions have no real impact on the environment.	Collective actions, like saving water, create significant positive change.

​

Summary

• Biodiversity is the variety of life and shows how healthy an ecosystem is.

• Healthy ecosystems provide essential services like water purification and nutrient recycling.

• Small changes in an ecosystem, like removing a species, can cause large impacts.

• Solutions to protect biodiversity must be judged by how well they work and their limits.

Poll

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

• 1

• 2

• 3

• 4