Best AP Environmental Science Quizlet Decks by Unit

8 min readjuly 11, 2024

Harrison Burnside

Harrison Burnside

Harrison Burnside

Harrison Burnside


AP Environmental Science ♻️

252 resources
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❓ Why Quizlet?

One of the most popular study sites used by AP students is Quizlet and for good reason! Quizlet combines the classic flashcard studying method with unique, fun games to learn vocabulary. However, the number of resources provided by Quizlet can make it challenging to find the best decks for each AP Environmental Science unit.
For that reason, here are the most comprehensive Quizlet decks for effective studying! Vocabulary is critical for understanding different ideas, theories, legislation, structures, concepts, and natural disasters.
⚡Tune in to a live stream for more review! 🎥 Check the calendar for upcoming streams.
For 2020 ONLY, Units 1-7 will be on your AP Exam! Units 8-9 will NOT be included as content on the exam. Find the 2020 exam schedule, learn tips & tricks, and get your frequently asked questions answered on Fiveable's Guide to the 2020 AP Exam Updates.

🙊 Unit 1: The Living World: Ecosystems

The first unit sets the foundation for the course by examining the Earth as a system with interdependent components, processes, and relationships. Students will examine the distribution of resources in ecosystems and its influences on species interactions. There is a global distribution of terrestrial and aquatic biomes—regional ecosystems—that each have specific environmental features based on their shared climate. This distribution is dynamic, and it has changed due to global climate change. Each ecosystem relies on biogeochemical cycles for survival. These cycles facilitate the acquisition and transfer of energy into usable forms, and they can be altered by human activities. In subsequent units, students will apply their understanding of ecosystems to the living world and examine the importance of biodiversity.
Key Terms:
  • Resource Partitioning: where two species divide a resource based on differences in the species' behavior or morphology; prevents competition
  • Symbiotic Relationship: the relationship of two species that live in close association with each other
  • Gross Primary Productivity - GPP:  the total amount of solar energy that the producers in an ecosystem capture via photosynthesis over a given amount of time
  • The 4 Major Biogeochemical Cycles: Nitrogen, Phosphorus, Carbon, and Water/Hydrologic Cycles -- the movement of matter within and between ecosystems

🌐 Unit 2: The Living World: Biodiversity

Biodiversity, which includes genetic, species, and habitat diversity, is critically important to ecosystems. Biodiversity in ecosystems is a key component to sustaining life within the living world. Natural and human disruptions have short- and long-term impacts on ecosystems. Ecological succession can occur in terrestrial and aquatic ecosystems in both developed and developing areas. Organisms within ecosystems must adapt to the changes created by these disruptions. In subsequent units, students will examine in greater detail how populations change over time.
Key Terms:
  • 4 Ecosystem Services: important environmental benefits provided to people such as clean air and water and fertile soil -- regulatory, cultural, supporting, provisional
  • Species Diversity: number of different species (species richness) combined with the relative abundance of individuals within each of those species (species evenness)
  • Bottleneck Effect: a change in allele frequency following a dramatic reduction in the size of a population

🗺️ Unit 3: Populations

Populations within ecosystems change over time in response to a variety of factors. This unit (3) examines the relationship between the type of species and the changes in a habitat over time. Specialist species are advantaged by habitats that remain constant, while generalist species tend to be advantaged by habitats that are changing. Different reproductive patterns, including those exhibited by K- and r-selected species, also impact changes to population. Population growth is limited by environmental factors, especially by the availability of resources and space. In subsequent units, students will explore how increases in populations affect earth systems and resources, land and water use, and energy resources.
Key Terms:
  • Biotic Potential: maximum rate at which a population can increase under ideal conditions, exponential growth
  • Doubling Time (Years): number of years it will take for a population to double = to 70%/population growth rate (%)
  • Demographic Transition Model: a sequence of demographic changes in which a country moves from high birth and death rates to low birth and death rates through time

🌱 Unit 4: Earth Systems and Resources

This unit explores earth systems and its resources that support life. Geological changes that occur to earth systems at convergent and divergent boundaries can result in the creation of mountains, island arcs, earthquakes, volcanoes, and seafloor spreading. Soils are a resource, formed when parent material is weathered, transported, and deposited. The atmosphere is another resource, composed of certain percentages of major gases. Climate is influenced by the sun’s energy, Earth’s geography, and the movement of air and water. In subsequent units, students will examine how humans use natural resources and the impact on the environment.
Key Terms:
  • Coriolis Effect: the effect of Earth's rotation on the direction of winds and currents
  • El Nino: the periodic changes in winds and ocean currents, causing cooler and wetter conditions in the southeastern United States and unusually dry weather in southern Africa and Southeast Asia
  • Soil Horizons: a layer of soil, approximately parallel to the surface, having distinct characteristics produced by soil-forming processes
  • Lithosphere: a rigid layer made up of the uppermost part of the mantle & the crust

🧨 Unit 5: Land and Water Use

This unit explores human activities that disrupt ecosystems both positively and negatively and the methods employed to reduce impact. It examines human use of natural resources through many means, including mining and clearcutting, and the impacts on the environment. Agricultural practices in particular can cause environmental disruption. For example, one of the largest uses of freshwater is for irrigation. Every irrigation method employed for agriculture has its own benefits and drawbacks. In subsequent units, students will examine different types of energy resources, the consumption of these resources, and the impact on the environment.
Key Terms:
  • Green Revolution: a shift in agricultural practices in the twentieth century that included new management techniques, mechanization, fertilization, irrigation, and improved crop varieties with increased yields
  • Synthetic Fertilizer: produced commercially, normally with the use of fossil fuels a.k.a as inorganic fertilizers
  • No-Till Agriculture: an agricultural method in which farmers do not turn the soil between seasons as a means of reducing topsoil erosion
  • Drip Irrigation: the practice of using small pipes that slowly drip water just above ground to conserve water to use for crops (highly efficient 75-95%)

⚡ Unit 6: Energy

This unit examines human use of renewable and nonrenewable sources of energy and its impact on the environment. Energy consumption differs throughout the world and the availability of natural energy resources depends on the region’s geologic history. Subsequent units will examine the impact of human activity on the atmosphere, land, and water.
Key Terms:
  • Nuclear Fission: a nuclear reaction in which a massive nucleus splits into smaller nuclei with the simultaneous release of energy
  • Dams: a barrier constructed to hold back water and raise its level, the resulting reservoir being used in the generation of electricity or as a water supply
  • Energy Efficient: energy efficient homes are composed of a network of elements working together to reduce the overall amount of energy consumption
  • Fossil Fuels: coal, oil, natural gas, and other fuels that are ancient remains of plants and animals

🌧️ Unit 7: Air Pollution

Air pollution has many sources and effects, both indoors and outdoors. Air is a natural resource that covers the Earth and crosses many system boundaries. Human activities affect the quality of the air both indoors and outdoors. Through legislation, the Clean Air Act regulates the emission of air pollutants that affect human health. The gases and particulates in the atmosphere come from both natural and human sources; once air pollution sources are identified, methods can be used to reduce it. Subsequent units will focus on pollution’s impacts to land and water.
Key Terms:
  • Sulfur Dioxide: SO2, a gas produced by coal burning which increases the acidification of rain water
  • Tropospheric Ozone: O3, ozone that occurs in the troposphere, where it is a secondary pollutant created by the interaction of sunlight, heat, nitrogen oxides, and volatile carbon containing chemicals
  • Clean Air Act: 1970- law that established national standards for states, strict auto emissions guidelines, and regulations, which set air pollution standards for private industry
  • Secondary Pollutant: a primary pollutant that has undergone transformation in the presence of sunlight, water, oxygen, or other compounds

🏭 Unit 8: Aquatic and Terrestrial Pollution

Pollution created by human activities directly impacts ecosystems in the air, on land, and in water. The source of pollution can sometimes be easy to identify, but other times the source is diffused. There are many human health issues that can be linked to pollution. Legislation has been created to reduce discharges of pollution in water and regulate drinking water. Increases in waste cause global concerns for organisms that live on land and in water. In the final unit, students will explore how local and regional human activities can have a global impact.
Key Terms:
  • Eutrophication:  process by which nutrients, particularly phosphorus and nitrogen, become highly concentrated in a body of water, leading to increased growth of organisms such as algae or cyanobacteria
  • Biomagnification: the concentration of toxins in an organism as a result of its ingesting other plants or animals in which the toxins are more widely disbursed
  • LD50: the amount of a chemical that kills 50% of the animals in a test population, measured on the dose-response curve
  • Leachate: polluted liquid produced by water passing through buried wastes in a landfill

♻️ Unit 9: Global Change

A central aspect of environmental science is to understand the global impact of local and regional human activities. Humans can mitigate their impact through sustainable use of resources. Human activities can cause ozone depletion in the stratosphere and increases in the greenhouse gases in the atmosphere. Increases in greenhouse gases can cause human health and environmental problems. These environmental problems include global climate change, ocean warming, and endangered species. Overall, this course provides an opportunity to examine the interrelationships among the natural world and challenges students to evaluate and propose solutions to a variety of environmental problems.
Key Terms:
  • Greenhouse Gases: gases such as water vapor, carbon dioxide, and methane that absorb heat leaving the Earth's surface adding to the greenhouse effect, where certain atmospheric gases allow visible light to pass but traps infrared heat heat
  • Kyoto Protocol: 1997 treaty that calls for industrialized countries to reduce greenhouse gas emissions
  • Endangered Species Act: 1973 U.S. legislation that implements CITES, Convention on International Trade of Endangered Species, designed to protect species from extinction; identifies/protects threatened and endangered species
  • Sea Level Rise: increase in average sea level over time, caused by thermal expansion of seawater and melting of land-based glaciers resulting in coastal flooding and more severe storm surges
 All unit overviews are courtesy of the College Board’s “AP Environmental Science: Course and Exam Description”

Browse Study Guides By Unit
🏜Unit 1 – The Living World: Ecosystems
🐠Unit 2 – The Living World: Biodiversity
👪Unit 3 – Populations
🌏Unit 4 – Earth Systems & Resources
🏖Unit 5 – Land & Water Use
⚡️Unit 6 – Energy Resources & Consumption
💨Unit 7 – Atmospheric Pollution
♻️Unit 8 – Aquatic & Terrestrial Pollution
🔥Unit 9 – Global Change
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