Week 5: Human Impact on Ecosystems
Grade 8 Science | Rosche | Kairos Academies
Integration Challenge - YOU Complete ALL Steps:
Your Turn - Advanced Integration:
Step 1: Verify the total ecosystem service value ($9.9B) by adding all categories. Which service is most valuable?
Step 2: If the reef loses 50% of its species (W4 food web complexity), how would each service category be affected? Estimate new values.
Step 3: Connect to W1-W4: How does energy flow support fish production and create economic value? How do decomposers (W3) enable nutrient cycling that maintains reef productivity?
Step 4: Write your argument: Should the reef be protected or developed? Use BOTH economic and ecological evidence.
Full Independence: Week 5 is the capstone - you've been building toward this all cycle! You have all the tools from Weeks 1-4. Now integrate them to solve complex, real-world problems.
Simulation: Ecosystem Services
PREDICT (before running the sim)
Look at the simulation controls. Before changing any variables, predict what will happen when you adjust them. Write your prediction down.
OBSERVE (while using the sim)
Change one variable at a time. Record what happens after each change. Use the data journal to capture at least 3 trials.
EXPLAIN (after collecting data)
Compare your observations with your prediction. Use scientific vocabulary to explain the patterns you found. What surprised you? What confirmed your thinking?
โผ Station 1 โ Ecosystem
Services Investigation โผ
20 Points | ~18 Minutes
Categorize ecosystem services and connect them to Cycle 4
concepts.
Your Mission: Categorize Ecosystem Services
The Four Categories of Ecosystem Services:
| Category | Examples | Connection to C4 |
|---|---|---|
| Provisioning | Food, water, timber, medicines | W1: Energy flow through food webs |
| Regulating | Climate, floods, water purification | W3: Decomposition cycles matter |
| Supporting | Nutrient cycling, soil, photosynthesis | W3-4: Matter cycling & food webs |
| Cultural | Recreation, tourism, spiritual value | All weeks: Healthy ecosystems |
Global Value of Ecosystem Services:
Scientists estimate Earth's ecosystems provide services worth $125-145 TRILLION per year. For comparison, the entire global economy is worth about $100 trillion. Nature is literally more valuable than all human economic activity combined!
COMPLETING THIS AT HOME? Use this reference:
Ecosystem Services Exploration:
- Watch: National Geographic: Ecosystem Services
- List 2-3 services you use every day without thinking about them
- Categorize each service using the table above
- Connect each service to a Week 1-4 concept
โผ Need extra support? Click for hints โผ
How to Categorize:
- Provisioning: Can you eat, drink, or build with it?
- Regulating: Does it control a process (climate, floods, disease)?
- Supporting: Does it make other services possible?
- Cultural: Does it provide non-material benefits?
Sentence Starters:
- "This is a provisioning service because we can harvest..."
- "This connects to Week ___ because..."
- "Without this service, humans would need to..."
โผ ๐ Stuck? Click here for step-by-step CER help โผ
Try these steps in order:
- Read each ecosystem service example in the table
- Ask: "What category does this fit?" Use the definitions above
- Think: "How does this connect to Weeks 1-4?"
- For the connection question, pick ONE week and explain the link
- Use the 10% rule (W1), invasive species (W2), decomposers (W3), or food web complexity (W4)
COMPLETE THE STATION 1 FORM BELOW
Categorize services and explain connections to earlier weeks.
Complete Your Worksheet โ Click to Expand
Complete the "Station 1" box in the "STATION 1 & 2 NOTES" section:
- One example of each category...
- The connection to Week ___ is...
- Key insight: (one sentence summary)
โผ Station 2 โ Economic Value
Analysis โผ
20 Points | ~15 Minutes
Calculate replacement costs to understand nature's true economic
value.
Your Mission: Calculate Nature's Value
What Would It Cost to Replace Nature?
| Ecosystem Service | Annual Value (US) | What Would Replace It |
|---|---|---|
| Pollination (bees) | $15 billion | Robot bees or human workers |
| Water purification (wetlands) | $4.9 trillion globally | Water treatment plants |
| Carbon storage (forests) | $4.7 trillion globally | Carbon capture technology |
| Pest control (birds, bats) | $4.5 billion | Pesticides (harm other species) |
| Flood control (wetlands) | $30 billion | Dams, levees, pumps |
Case Study: New York City Water
NYC gets clean drinking water from the Catskill Mountains watershed. In the 1990s, the city faced a choice:
- Build a $6 billion water treatment plant, OR
- Spend $1.5 billion protecting the watershed
- They chose the watershed - saved $4.5 billion!
LESSON: Nature provides better water purification AND is cheaper to maintain!
โผ Need extra support? Click for analysis hints โผ
Analysis Strategy:
- Find the most valuable service in the table
- Think about what humans would need to BUILD to replace it
- Ask: "Is the replacement cheaper or more expensive than protecting nature?"
Sentence Starters:
- "Protecting ecosystems is cheaper than replacing their services because..."
- "When biodiversity decreases, ecosystem services _____ because..."
- "The NYC watershed example shows that..."
โผ ๐ Stuck? Click here for step-by-step CER help โผ
Try these steps in order:
- Look at the table - find the service with the highest value
- Think about what humans would need to BUILD to replace it
- Ask: "Is the replacement cheaper or more expensive than protecting nature?"
- Use the NYC example as a model for your reasoning
- Connect to Week 4: More complex ecosystems = more resilient = better services
COMPLETE THE STATION 2 FORM BELOW
Calculate replacement costs and analyze the NYC case study.
Complete Your Worksheet โ Click to Expand
Complete the "Station 2" box in the "STATION 1 & 2 NOTES" section:
- The most valuable ecosystem service is...
- Replacement would cost _____ because...
- Key insight: (one sentence summary)
โผ Exit Ticket โ Ecosystem
Services Integration โผ
23 Points | ~15 Minutes
Demonstrate mastery by integrating concepts from all Cycle 4
weeks.
Show What You Learned
Question Types:
- 2 NEW - Ecosystem services and economic valuation (this week)
- 2 SPIRAL - Review of Weeks 1-4 (energy flow, invasive species, decomposition, food webs)
- 1 INTEGRATION - Connect ecosystem services to ALL C4 concepts
- 1 SEP - Develop a model or analyze data about ecosystem services
โผ Autonomy Support: How to Ace
the Exit Ticket (23 pts) โผ
Quick review of ALL Cycle 4 concepts you'll need.
The Exit Ticket tests INTEGRATION - connecting ALL Cycle 4 concepts. Here's how to prepare:
Quick Review Before You Start:
- Week 1 (10% Rule): Only 10% of energy transfers between levels - limits population sizes and affects provisioning services
- Week 2 (Invasive Species): Invasive species disrupt ecosystem services by disrupting food webs
- Week 3 (Decomposition): Decomposers enable nutrient cycling - a critical supporting service
- Week 4 (Food Web Complexity): More complex ecosystems = more resilient = better services
- Week 5 (Ecosystem Services): Four categories, economic valuation, replacement costs
Integration question tip: The best answers connect at least 3 weeks together. Example: "Bees support PROVISIONING services (pollination for food). Without bees, food webs (W4) lose complexity. Fewer pollinators means less energy flow (W1) through the ecosystem, which reduces ALL other services."
COMPLETE THE EXIT TICKET BELOW
This is your capstone assessment for Cycle 4. Take your time and integrate ALL concepts!
Complete Your Worksheet โ Click to Expand
Complete the "DAY 2 EXIT TICKET" and "SCIENCE CIRCLE" sections:
- Q1-Q2 (NEW): Ecosystem services categories and economic valuation
- Q3-Q4 (SPIRAL): Apply concepts from Weeks 1-4
- Q5 (INTEGRATION): Connect ecosystem services to food webs and energy flow
- Science Circle: Your "Aha!" moment and remaining question
Bonus: +5 points for Exit Ticket section, +3 points for Science Circle!
โผ Enrichment & Extension โผ
Optional deep dives into ecosystem economics, scientist profiles,
and environmental justice.
Optional content if you finish early or want to go deeper.
Systems Thinking: The Interconnected Economy of Nature
Ecosystem services don't exist in isolation - they're interconnected through the same food webs and energy flows you studied in Weeks 1-4. When pollinators decline, provisioning services (food production) suffer, which affects cultural services (agricultural tourism), which reduces economic incentives for conservation, which accelerates pollinator decline further. This feedback loop shows why protecting ONE service often protects MANY services simultaneously.
Scientist Spotlight: Dr. Gretchen Daily
Dr. Gretchen Daily is a conservation biologist at Stanford University who revolutionized how we value nature. In the 1990s, when most economists ignored environmental costs, Dr. Daily asked: "What if we calculated the dollar value of everything nature does for free?" Her groundbreaking 1997 book, Nature's Services, launched the field of ecosystem services science. She co-founded the Natural Capital Project, which helped China invest $40 billion in ecological restoration and created Costa Rica's payment programs for forest protection.
Environmental Justice: St. Louis Floodplain Loss & Climate Vulnerability
St. Louis sits in a critical zone where the Mississippi River floodplain once provided natural flood control, water filtration, and erosion protection worth billions. Since 1950, the St. Louis metro area has lost over 40% of floodplain forests and wetlands to levee development, agriculture, and industrial expansion - with the heaviest losses affecting low-income neighborhoods and communities of color.
Connection to Ecosystem Services: When developers destroy wetlands to build levees and highways, the flood control, water purification, and habitat services disappear - but the costs are borne by communities with the least political power to stop it. Protecting ecosystem services is a matter of justice: Who benefits from development? Who pays when nature's services are eliminated?
Week 5 Complete - Cycle 4 Capstone!
You've integrated energy flow, invasive species, decomposition, food webs, and ecosystem services. Next cycle: Apply these concepts to new ecosystems!