Science · Grade 9 · Sustainable Ecosystems and Stewardship · Term 1

Biodiversity and Ecosystem Services

Exploring the importance of biodiversity and the services healthy ecosystems provide.

• Ontario Curriculum Expectations
• HS-LS2-7
• HS-LS4-6

About This Topic

Biodiversity includes the variety of genes, species, and ecosystems, crucial for stability and resilience in sustainable systems. Grade 9 students justify its importance by examining how diverse communities recover faster from events like fires or storms, using Ontario examples such as Carolinian forests. They analyze invasive species impacts, like garlic mustard crowding out natives in woodlands, which shifts food webs and reduces services. Ecosystem services fall into provisioning (food, medicine), regulating (pollination, water filtration), cultural (tourism), and supporting categories, with clear economic value through sectors like agriculture and fisheries.

This topic supports Ontario curriculum goals in stewardship, building analysis and evaluation skills. Students link biodiversity loss to human actions, fostering evidence-based arguments on conservation.

Active learning suits this content well. When students audit local biodiversity or simulate invasive introductions with games, they observe dynamics directly. Collaborative projects quantify services, making abstract values concrete and motivating real-world application.

Key Questions

1. Justify the importance of biodiversity for ecosystem stability and resilience.
2. Analyze how the introduction of an invasive species alters the equilibrium of a local habitat.
3. Evaluate the economic and ecological value of various ecosystem services.

Learning Objectives

• Justify the importance of biodiversity for ecosystem stability and resilience using specific examples.
• Analyze how the introduction of an invasive species, such as garlic mustard, alters the equilibrium of a local habitat's food web.
• Evaluate the economic and ecological value of at least three distinct ecosystem services, such as pollination or water filtration.
• Compare the impact of biodiversity loss on ecosystem services in a natural setting versus an agricultural setting.
• Synthesize information to propose a stewardship action that could enhance local biodiversity.

Before You Start

Ecosystems and Food Webs

Why: Students need to understand how energy flows and organisms interact within an ecosystem to analyze the impact of biodiversity loss and invasive species.

Human Impact on the Environment

Why: Prior knowledge of human activities affecting ecosystems provides context for understanding the causes and consequences of biodiversity loss.

Key Vocabulary

Biodiversity	The variety of life in a particular habitat or ecosystem, encompassing genetic, species, and ecosystem diversity.
Ecosystem Services	The benefits that humans receive from healthy ecosystems, categorized as provisioning, regulating, cultural, and supporting services.
Invasive Species	A non-native species whose introduction causes or is likely to cause economic or environmental harm to the ecosystem.
Ecosystem Stability	The ability of an ecosystem to resist disturbance and recover its structure and function over time.
Resilience	The capacity of an ecosystem to absorb disturbance and reorganize while undergoing change so as to essentially retain the same function, structure, and feedbacks.

Watch Out for These Misconceptions

Common Misconception

Biodiversity means just counting more species.

What to Teach Instead

Diversity involves functional roles and interactions; simple counts ignore keystone species. Biodiversity audits and simulations help students map connections, revealing why balanced roles sustain services.

Common Misconception

Ecosystems naturally stay balanced despite invasives.

What to Teach Instead

Invasives disrupt equilibrium by altering competition and chains. Role-play games let students witness rapid shifts, prompting revision of static views through data tracking.

Common Misconception

Ecosystem services have no real economic cost.

What to Teach Instead

Services like pollination save billions in crops; loss incurs high replacement costs. Jigsaw activities quantify local values, connecting ecology to economics via shared research.

Active Learning Ideas

Field Survey: Local Biodiversity Audit

Small groups use quadrats and identification apps to catalog species in school grounds or nearby parks. Calculate Shannon diversity index from data. Present findings on threats and services in a class chart.

50 min·Small Groups

Role-Play Simulation: Invasive Species Arrival

Pairs draw species cards for a habitat model; introduce invasive cards with advantages like rapid reproduction. Simulate 5-6 generations, graphing population shifts. Discuss equilibrium changes in debrief.

35 min·Pairs

Jigsaw: Types of Ecosystem Services

Assign small groups one service category; research Ontario examples and values. Regroup to teach peers, then co-create a services map. Evaluate top priorities as a class.

45 min·Small Groups

Formal Debate: Service Valuation

Divide whole class into economic and ecological value teams. Use evidence from prior activities to argue priorities. Vote and reflect on trade-offs.

40 min·Whole Class

Real-World Connections

• Conservation biologists working for organizations like Nature Conservancy Canada assess the health of Carolinian forests, identifying areas needing protection to maintain high biodiversity and prevent species loss.
• Urban planners in Toronto consider the value of ecosystem services, such as stormwater management provided by green infrastructure like parks and bioswales, when designing new developments.
• Fisheries managers in Newfoundland and Labrador use data on fish populations and ecosystem health to set sustainable catch limits, ensuring the long-term viability of the fishing industry.

Assessment Ideas

Discussion Prompt

Pose the question: 'Imagine a local park loses half its plant species due to disease. Describe two ways this loss would likely impact the park's ecosystem services and its overall resilience.' Facilitate a class discussion, encouraging students to reference specific services and stability concepts.

Quick Check

Provide students with a short case study about the introduction of zebra mussels into Lake Ontario. Ask them to identify the invasive species, list two ways it has altered the lake's ecosystem, and explain one economic impact.

Exit Ticket

On an index card, have students write down one specific ecosystem service they benefit from daily (e.g., clean air, food) and then list one action they could take to help protect the ecosystem that provides it.

Frequently Asked Questions

What are key ecosystem services in Ontario?

Ontario wetlands provide regulating services like flood control and water purification, worth millions annually. Forests offer provisioning services such as timber and berries, plus cultural recreation in parks. Pollination by native bees supports $1 billion in agriculture. Students evaluate these through local case studies to grasp full value.

How do invasive species impact biodiversity?

Invasives like zebra mussels filter plankton, starving native fish and altering Great Lakes food webs. They reduce diversity by outcompeting locals, weakening resilience. Simulations show cascading effects on services, such as diminished fishing yields, helping students analyze habitat changes.

How can active learning help teach biodiversity and services?

Field audits engage students in real data collection, building ownership of concepts. Simulations and jigsaws promote collaboration, where peers challenge ideas and reveal interconnections. These methods shift passive recall to active analysis, deepening understanding of stability and motivating stewardship through tangible local links.

Why justify biodiversity for ecosystem stability?

Diverse systems buffer disturbances via redundancy; lose bees, other pollinators compensate. Monocultures collapse easily, as in potato famines. Audits and debates let students compare diverse vs simple models, justifying conservation with evidence on resilience and services.