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Unit 5 · Land & Water Use Unit Hub Flashcards Cheat Sheet Essentials Visual Review MC Practice FRQ Practice
Unit 5 · 10–15% of Exam

Land & Water Use

The human footprint on land and water. The tragedy of the commons, clearcutting, the Green Revolution, irrigation and pest control, meat production, overfishing, mining, urbanization, and the sustainability tradeoffs behind every way humans use land and water.

17 topics
~18–19 class periods
2 Big Ideas covered
College Board aligned
← Back to AP Environmental Science

Choose your study tool

Six ways to master Unit 5 — pick whichever fits how you like to study.

Flashcards
25 interactive flashcards covering every key term from Unit 5. Tap to flip, shuffle, and use keyboard arrows.
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Cheat Sheet
A one-page visual summary of Unit 5 — every key topic, term, and theme on a single screen.
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Essentials
The big ideas plus a searchable glossary of every vocabulary term you need to know for the exam.
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Visual Review
A slide-by-slide walkthrough of Unit 5 with diagrams of irrigation, fishing methods, and urban sprawl.
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MCQ Practice
33 multiple-choice questions in College Board exam style — with full explanations of every answer.
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FRQ Practice
A free-response question with model answers showing exactly how each part earns its point on the exam.
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Topics in Unit 5

Seventeen topics from the College Board CED, in order.

Topic 5.1
The Tragedy of the Commons
Why shared, unregulated resources tend to be overexploited when individuals act in their own self-interest.
Topic 5.2
Clearcutting
The removal of all trees in an area, and its impacts on soil erosion, biodiversity, and the water cycle compared to selective cutting.
Topic 5.3
The Green Revolution
The mid-20th-century shift to high-yield crop varieties, synthetic fertilizer, and irrigation that dramatically increased food production.
Topic 5.4
Impacts of Agricultural Practices
How monoculture, tillage, and fertilizer/pesticide use affect soil health, water quality, and biodiversity.
Topic 5.5
Irrigation Methods
Flood, drip, and spray irrigation, and their tradeoffs in water efficiency, cost, and soil salinization risk.
Topic 5.6
Pest Control Methods
Chemical pesticides vs. biological and integrated pest management, and the tradeoffs of each approach.
Topic 5.7
Meat Production Methods
Feedlots (CAFOs) vs. free-range systems, and their relative impacts on land, water, and greenhouse gas emissions.
Topic 5.8
Impacts of Overfishing
How unsustainable fishing practices deplete fish stocks and disrupt marine food webs.
Topic 5.9
Impacts of Mining
Surface and subsurface mining methods, and their effects on habitat destruction, water pollution, and land reclamation.
Topic 5.10
Impacts of Urbanization
How urban growth affects impervious surfaces, the urban heat island effect, and local water and air quality.
Topic 5.11
Ecological Footprints
A measure of the land and resources required to support a population's consumption and absorb its waste.
Topic 5.12
Introduction to Sustainability
Meeting present needs without compromising the ability of future generations to meet their own — plus concepts like maximum sustainable yield.
Topic 5.13
Methods to Reduce Urban Runoff
Permeable pavement, rain gardens, and retention ponds that limit stormwater runoff and the pollution it carries.
Topic 5.14
Integrated Pest Management
Combining biological, mechanical, and limited chemical controls to manage pests while reducing pesticide use.
Topic 5.15
Sustainable Agriculture
Crop rotation, contour plowing, no-till farming, and other practices that protect soil and water for the long term.
Topic 5.16
Aquaculture
Farming fish and shellfish — its potential to relieve pressure on wild stocks alongside its pollution and habitat impacts.
Topic 5.17
Sustainable Forestry
Selective cutting, reforestation, and prescribed burns that let forests be used while keeping them healthy.

About Unit 5

Unit 5 surveys the major ways humans use land and water — agriculture, forestry, fishing, mining, and urban development — and the environmental tradeoffs each one carries. The unifying thread is the tragedy of the commons: when a resource is shared and unregulated, individual incentives often lead to overexploitation, whether it's overfishing, overgrazing, or clearcutting.

This unit is roughly 10–15% of the AP Environmental Science exam and takes about 18–19 class periods — it's the most topic-dense unit on the exam, covering 17 distinct content areas, so expect broad, varied question coverage.

The College Board ties Unit 5 to two Big Ideas:

Big Idea: STB
Sustainability — tradeoffs in resource use and land management
Big Idea: EIN
Interactions Between Species & Environment — agriculture, fishing, and biodiversity impacts
Up next
Unit 6: Energy Resources & Consumption
Start Unit 6 →