Complete Breakdown of Unit 8: Aquatic Pollution and Ecology

Point Source

A single, identifiable source of distinct discharge, easy to manage and regulate.

Nonpoint Source

Diffuse areas that produce pollution, often from runoff over large land areas, difficult to identify and manage.

Clean Water Act

A key U.S. law regulating point and nonpoint sources of pollution in waters.

Biological Oxygen Demand (BOD)

A measure of the amount of oxygen that microorganisms will consume while decomposing organic matter in water.

Dissolved Oxygen (DO)

The amount of oxygen that is present in water, essential for aquatic life.

Oxygen Sag Curve

Graph illustrating the relationship between BOD and DO levels in water following pollution.

Coral Bleaching

A phenomenon where corals expel their symbiotic algae due to stress, turning white and becoming more susceptible to death.

Ocean Acidification

The reduction of pH in ocean water due to increased atmospheric carbon dioxide levels.

Methylmercury

A highly toxic form of mercury that biomagnifies in the food chain, causing neurological damage.

Endocrine Disruptors

Chemicals that interfere with the hormonal systems of animals, mimicking or blocking natural hormones.

Range of Tolerance

The range of abiotic conditions that an organism can endure before experiencing stress or death.

Bioaccumulation

The accumulation of toxins in an individual organism over time.

Biomagnification

The increasing concentration of toxins in organisms at each successive level of the food chain.

Atrazine

An herbicide that contaminates water supplies and can cause demasculinization in amphibians.

DDT

An insecticide banned in many nations due to environmental persistence and health effects.

Heavy Metals

Toxic metallic elements that can cause pollution, such as mercury and lead.

Filtration Services

The process by which wetlands filter pollutants and sediments from water.

Flood Control

Wetlands absorb excess water to prevent flooding downstream.

Groundwater Recharge

The process of water percolating down from the surface to replenish aquifers.

Aquaculture

The farming of aquatic organisms, which can lead to destruction of mangroves and wetlands.

NPDES

National Pollutant Discharge Elimination System; a permit system for regulating point source discharges.

Plastic Litter

Waste materials that can harm wildlife when ingested or cause strangulation.

Turbidity

The cloudiness of a fluid caused by large numbers of individual particles; affects light penetration in water.

Sediment Runoff

Soil and dirt that are washed into waterways, which can harm water quality and aquatic habitats.

Breeding Zones

Areas within ecosystems that serve as critical nurseries for various aquatic species.

Stormwater Runoff

Water from rain or snowmelt that does not soak into the ground, often carrying pollutants to waterways.