APES UNIT 8

Study set for APES Unit 8 2026

Algal Bloom

An immediate increase in algae and other producers due to a large input of a limiting nutrient.

Biochemical Oxygen Demand (BOD)

The amount of oxygen required by aquatic bacteria to decompose organic waste; a measure of water pollution.

Biomagnification

The increase in chemical concentration in tissues as a chemical moves up the food chain.

Example of biomagnification

Eggshell thinning and developmental deformities in top carnivores.

Effects of biomagnification on humans

Includes problems with reproductive, nervous, and circulatory systems.

Substances that bioaccumulate

DDT, mercury, and PCBs (polychlorinated biphenyls).

Polychlorinated biphenyls (PCBs)

Industrial compounds used to manufacture plastics and insulate electrical transformers.

Bioaccumulation

The selective absorption and concentration of compounds by organisms, especially fat-soluble substances.

Boom

A floating barrier used to contain an oil spill.

Bubonic Plague

Disease spread by fleas and rats that killed about one-third of Europe's population in the Middle Ages.

Cholera

An intestinal infection caused by drinking contaminated water or eating contaminated food.

Composting

The decomposition of organic waste into nutrient-rich soil material.

Drawbacks of composting

Odor, rodents, and attraction of animals such as bears.

How can e-waste be reduced?

By recycling and reusing electronics.

Negative impacts of e-waste

Contains hazardous chemicals like lead and mercury that can contaminate groundwater.

Landfill mitigation strategies

Burning waste for energy or restoring landfill areas into parks.

Negative impacts on coral reefs

Ocean warming, sediment runoff, and destructive fishing practices damage reefs.

Coral Bleaching

When algae inside corals die, causing the coral to turn white.

Dead Zone

An area of water with very low oxygen and little life.

Decomposition

A chemical reaction that breaks down compounds into simpler substances.

Effects of oil spills

Oil kills organisms, coats feathers and fur, and harms bottom-dwelling species.

Economic consequences of oil spills

Reduces fishing profits and tourism.

Dispersant

Chemicals used to break up oil into smaller particles.

Dose Response Curve

Shows the relationship between toxin exposure and organism response.

Why is cause and effect hard to establish?

Humans are exposed to many pollutants simultaneously.

E-Waste

Discarded electronic devices such as phones and computers.

Endocrine Disruptors

Chemicals that interfere with hormone systems.

Impacts of endocrine disruptors

Cause birth defects, developmental problems, and gender imbalances.

Examples of endocrine disruptors

DDT, PCBs, and BPA in plastics.

Eutrophication

Excess nutrients cause rapid algae growth and oxygen depletion.

How algal blooms impact environments

Block sunlight, kill plants, and lower oxygen levels.

Fecal Coliform Bacteria

Bacteria used as indicators of sewage contamination.

Great Pacific Garbage Patch

A massive collection of floating plastic waste in the Pacific Ocean.

Hypoxic waterways

Waterways with low dissolved oxygen.

Incineration

Burning waste to reduce volume and generate energy.

Advantages of incineration

Reduces waste volume by about 90% and produces usable heat.

Disadvantages of incineration

Produces toxic emissions and leftover ash requiring disposal.

Illegal disposal of waste

Waste dumped improperly causing environmental damage.

Why rubber tires are a problem

Collect water and become mosquito breeding grounds.

Indicator Species

Species used to detect environmental changes.

Leachate

Polluted liquid formed when water passes through landfill waste.

Malaria

Disease spread by mosquitoes, common in tropical regions.

Mangroves

Coastal trees that protect shorelines and ecosystems.

Maximum Containment Level (MCL)

The legal maximum concentration of contaminants allowed in drinking water.

MERS

A viral respiratory illness transmitted from animals to humans.

Mesothelioma

A cancer associated with asbestos exposure.

Mercury changes in water

Bacteria convert mercury into toxic methylmercury.

Methylmercury

A toxic form of mercury that accumulates in fish and harms the nervous system.

Nonpoint Source Pollution

Pollution from widespread sources without a single identifiable origin.

Oligotrophic waterways

Lakes with low nutrients and high oxygen levels.

Anthropogenic causes of eutrophication

Agricultural runoff and wastewater discharge.

Oxygen Sag Curve

Shows oxygen levels decreasing downstream from pollution discharge.

Industry impacts on drinking water

Heavy metals from industry contaminate groundwater.

Impact of litter on ecosystems

Causes choking hazards and introduces toxins into food chains.

Impact of sediment in waterways

Reduces sunlight and disrupts aquatic habitats.