Ecosystem Stability and Disturbances

Active learning helps students move beyond abstract definitions by letting them manipulate models and analyze real cases. When students test resistance and resilience using hands-on tools like Stability Jenga or compare case studies, they see how ecosystems respond differently to disturbances. These experiences make the vocabulary stick and prepare students to apply the concepts to new situations.

• 6th Grade
• Science
• 3 activities
• 20 min–45 min

Learning Objectives

1. Analyze case studies to explain how specific US ecosystems recover after a major disturbance, such as a forest fire or drought.
2. Compare and contrast the concepts of ecosystem resistance and resilience using examples of different habitats.
3. Evaluate the factors, including biodiversity and keystone species, that contribute to the stability of US ecosystems during periods of drought.
4. Synthesize information from scientific articles to propose strategies for enhancing ecosystem resilience in the face of climate change.

Case Study Analysis

⏱ 45 min·Small Groups

Case Study Comparison: Fire Recovery vs. Invasive Species

Assign half the class to research the Yellowstone fire recovery (1988-present) and the other half to research a local or regional invasive species impact. Each group identifies whether the ecosystem showed resistance, resilience, or neither, and the factors that influenced the outcome. Groups present to each other and the class synthesizes a list of factors that promote ecosystem stability.

Prepare & details

Explain how ecosystems recover after a major forest fire.

Facilitation Tip: During Case Study Comparison: Fire Recovery vs. Invasive Species, have students highlight specific evidence in each case that shows either resistance or resilience before they discuss their findings.

Setup: Groups at tables with case materials

Materials: Case study packet (3-5 pages), Analysis framework worksheet, Presentation template

• Analyze
• Evaluate
• Create
• Decision-Making
• Self-Management

Simulation Game

⏱ 25 min·Small Groups

Simulation Game: Stability Jenga

Use a block tower where each block is labeled with a species or function in an ecosystem. Students take turns removing blocks (simulating species loss or disturbance) while the class predicts at each step whether the ecosystem can remain stable. After the tower falls, discuss which removals were most destabilizing and what that reveals about keystone species and functional redundancy.

Prepare & details

Differentiate between resistance and resilience in an ecosystem.

Facilitation Tip: During Simulation: Stability Jenga, circulate and ask students to explain which blocks represent species with high resistance versus those with high resilience in their tower.

Setup: Flexible space for group stations

Materials: Role cards with goals/resources, Game currency or tokens, Round tracker

• Apply
• Analyze
• Evaluate
• Create
• Social Awareness
• Decision-Making

Think-Pair-Share

⏱ 20 min·Pairs

Think-Pair-Share: Drought Resilience

Present data from two ecosystems facing the same drought: a monoculture cornfield and a tallgrass prairie. Pairs analyze which is more resilient and explain why, using evidence about biodiversity, root depth, soil structure, and species interactions. Pairs share their reasoning, and the class builds a conceptual model of what structural features predict resilience.

Prepare & details

Analyze the factors that make some ecosystems more stable than others during a drought.

Facilitation Tip: During Think-Pair-Share: Drought Resilience, explicitly remind pairs to use the drought data table to justify their predictions about ecosystem recovery.

Setup: Standard classroom seating; students turn to a neighbor

Materials: Discussion prompt (projected or printed), Optional: recording sheet for pairs

• Understand
• Apply
• Analyze
• Self-Awareness
• Relationship Skills

Teaching This Topic

Teachers should anchor this topic in tangible examples before moving to abstract reasoning. Start with simulations or case studies to build intuition, then layer in vocabulary and comparisons. Avoid front-loading definitions; instead, let students construct meaning through observation and discussion. Research shows that students grasp stability concepts better when they explore multiple disturbances rather than a single example.

What to Expect

Students will confidently explain the difference between resistance and resilience in their own words. They will use evidence from simulations and case studies to support their reasoning about ecosystem responses to disturbances. Clear evidence of success includes accurate vocabulary use and logical connections between activity examples and the definitions.

Watch Out for These Misconceptions

Common Misconception

During Case Study Comparison: Fire Recovery vs. Invasive Species, watch for students assuming the post-fire forest will be identical to the pre-fire forest.

What to Teach Instead

Use the Yellowstone case study materials to guide students in comparing species lists before and after the fire. Ask them to note differences and discuss why the new forest might not be a perfect 'reset'.

Common Misconception

During Simulation: Stability Jenga, watch for students generalizing that larger ecosystems are automatically more stable.

What to Teach Instead

After the simulation, have students compare towers of different sizes with varying biodiversity. Ask them to identify which combination showed the most stability and why.

Common Misconception

During Think-Pair-Share: Drought Resilience, watch for students assuming human cleanup efforts will always restore an ecosystem to its original state.

What to Teach Instead

Use the drought case study data to prompt students to evaluate whether the ecosystem returned to its pre-drought conditions or shifted to a new stable state.

Assessment Ideas

Exit Ticket

After Case Study Comparison: Fire Recovery vs. Invasive Species, ask students to write one sentence defining resistance and one sentence defining resilience using evidence from the case studies. Then, have them predict which concept—resistance or resilience—might be more important for the long-term survival of a coastal wetland after a hurricane.

Quick Check

During Simulation: Stability Jenga, provide two brief case studies of ecosystems recovering from disturbances. Ask students to identify one factor that promoted resistance in the first ecosystem and one factor that promoted resilience in the second, writing their answers in their notebooks.

Discussion Prompt

During Think-Pair-Share: Drought Resilience, pose the question: 'Imagine a forest ecosystem that is highly resistant to small, frequent fires but takes a very long time to recover from a single, massive wildfire. Is this ecosystem more resistant or more resilient?' Facilitate a class discussion where students justify their answers using the vocabulary terms and evidence from the activity.

Extensions & Scaffolding

• Challenge: Ask students to research a local ecosystem disturbance and design a simple simulation or model to test resistance or resilience.
• Scaffolding: Provide sentence frames for students to use during discussions, such as 'The ecosystem showed resistance because...' or 'The high resilience in this case is due to...'.
• Deeper exploration: Have students investigate how climate change alters disturbance patterns in ecosystems and predict changes in resistance or resilience.

Key Vocabulary

Ecosystem Disturbance	An event that disrupts the structure of an ecological community, such as a wildfire, flood, or human development.
Ecosystem Resistance	The ability of an ecosystem to remain relatively unchanged and maintain its structure and function when faced with a disturbance.
Ecosystem Resilience	The ability of an ecosystem to recover and return to its original state or a similar state after experiencing a disturbance.
Biodiversity	The variety of life within a particular habitat or ecosystem, including the diversity of species, genes, and ecosystems.
Keystone Species	A species that has a disproportionately large effect on its environment relative to its abundance, playing a critical role in maintaining ecosystem structure.