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Point source pollution

Comes from an identifiable source.

Nonpoint source pollution

Involves sources from a wide area.

Coral bleaching

The loss of algae from coral reefs.

Reasons for loss of coral reefs

Ocean warming, sediments, and increase in acidity.

Sediment in the ocean

Comes from land erosion and biological activity.

Acidity in the ocean

Caused by carbon dioxide.

Hypoxic areas in the ocean

Caused by nitrates and phosphates.

Methods for cleaning oil spills

Dispersants and oil booms.

DO

Dissolved oxygen; good quality water is indicated by a level of 8.

BOD

Biological oxygen demand; amount of oxygen decay bacteria consume, with a good quality water level of 2.

Main factor responsible for BOD

The presence of organic matter in water.

Septic zone in a stream

There is no life.

Common heavy metal pollutants

Mercury, lead, cadmium.

Methylmercury

A more toxic form of mercury that forms when mercury combines with water bacteria.

Turbidity

The amount of sediment in water.

High turbidity effects

Decreases light which destroys the bottom of the food chain, settles over habitats and makes it difficult for predators to see.

Common endocrine disruptors

PCB and BPA.

Wetland

Area that is covered by water at some point during the year.

Value of wetlands

High primary productivity, prevent flooding, stop pollution in the ocean.

Destruction of wetlands

Commercial development, dam construction, overfishing, pollutants from agriculture and industrial waste.

Main source of thermal pollution

Power plants.

Most affected factor by thermal pollution

Oxygen levels.

Persistent

Continues to exist.

Bioaccumulation in animals

Fat-soluble chemicals.

Animals affected by biomagnification

Animals at the top of the pyramid.

Chemicals implicated in biomagnification

DDT, mercury, and PCB.

Clean Water Act

First passed in 1972.

Safe Drinking Water Act

Passed in 1974; its main emphasis is to set levels of particular pollutants that water treatment plants are allowed to leave in drinking water.