AP Environmental Science — Unit 5: Land and Water Use

What AP Environmental Science Unit 5 covers

The College Board Course and Exam Description breaks Unit 5 into 17 topics:

1. 5.1 The Tragedy of the Commons
2. 5.2 Clearcutting
3. 5.3 The Green Revolution
4. 5.4 Impacts of Agricultural Practices
5. 5.5 Irrigation Methods
6. 5.6 Pest Control Methods
7. 5.7 Meat Production Methods
8. 5.8 Impacts of Overfishing
9. 5.9 Impacts of Mining
10. 5.10 Impacts of Urbanization
11. 5.11 Ecological Footprints
12. 5.12 Introduction to Sustainability
13. 5.13 Methods to Reduce Urban Runoff
14. 5.14 Integrated Pest Management
15. 5.15 Sustainable Agriculture
16. 5.16 Aquaculture
17. 5.17 Sustainable Forestry

AP Environmental Science Unit 5 practice questions

• What is the tragedy of the commons?

  Individuals overuse a shared resource for self-interest, depleting it for all. Each gains personally while the cost is spread to everyone.

• An ocean fishery is open to all countries with no catch limits. What outcome does the tragedy of the commons predict?

  Each country maximizes its own catch, causing overfishing and collapse. No one limits use, so the shared stock crashes.

• A logging company wipes out every tree in a plot at once, even though it knows this triggers massive erosion. Why would they choose the method with the worst environmental cost?

  Clearcutting — removing all trees at once because it's the cheapest method. Despite erosion and habitat loss, it's the most economically efficient way to harvest timber.

• A large forest is clearcut and the slash is burned. What are TWO environmental consequences?

  Soil erosion increases from lost root systems, and burning releases CO₂. The CO₂ adds to climate change; erosion degrades water quality.

• It carried the word 'Green' and fed billions more people — yet it's blamed for soil degradation, fossil-fuel dependence, and fertilizer runoff. What mid-20th-century agricultural shift was this?

  The Green Revolution — the mid-1900s shift to high-yield industrial agriculture. It used synthetic fertilizers, pesticides, irrigation, and GMO crops to boost food.

• How does increased mechanization of farming affect fossil fuel use and farm efficiency?

  Mechanization raises farm efficiency and profit but increases fossil fuel reliance. Equipment runs on fuel, adding carbon emissions.

• What is slash-and-burn agriculture, and what environmental problem does it cause?

  Cutting and burning vegetation to clear cropland; it releases CO₂ and erodes soil. Nutrient loss follows as ash washes away.

• Excess synthetic fertilizer is applied to a cornfield, and heavy rain follows. Trace the likely downstream environmental impact.

  Fertilizer runoff adds excess nitrogen and phosphorus, triggering algal blooms. Blooms cause eutrophication and a hypoxic dead zone.

+ 27 more AP Environmental Science cards in the app.

Key terms in Unit 5

These 12 terms show up in the Unit 5 cards. Each one links to its definition in the AP Environmental Science key-term reference.

• Aquifer depletion
• Ecological footprint
• Flood irrigation
• Genetic diversity
• Integrated pest management
• No-till agriculture
• Permeable pavement
• Pesticide resistance
• Rotational grazing
• Slash-and-burn agriculture
• Sustainable yield
• Tragedy of the commons