Special compounds containing nitrogen and oxygen

Chemicals used to make fertilizer

A measure of how clear water is.

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organisms or components of organisms that are used to assess the health of a water system

A measure of how hot or cold something is.

Measure of water quality indicating free oxygen dissolved in water.

The water and human wastes that are washed down sinks, toilets, and showers

A 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.

Rain or another form of precipitation that is more acidic than normal, caused by the release of molecules of sulfur dioxide and nitrogen oxide into the air.

The process by which particles in a liquid clump together.

Fecal coliform bacteria should not be found in sources of drinking water. Their presence in water serves as a reliable indication of contamination from human sewage or animal droppings.

The amount of one substance in a certain volume of another substance.

The practice of using less of a resource so that it will not be used up.

Any foreign components in a substance, for example in water.

The process of obtaining fresh water from salt water by removing the salt.

The process of passing water through a series of screens that allow the water through, but not larger solid particles.

The level of the minerals calcium and magnesium in water.

A chemical material or solution which can be used to show (usually by a change in color) the endpoint of a chemical reaction or chemical concentration. Examples are litmus and phenolphthalein.

The process of supplying water to areas of land to make them suitable for growing crops.

small, spineless creatures that are visible with the unaided eye; they include organisms such as crustaceans, mollusks, worms, and insects

A widely spread source of pollution that is difficult to link to a specific point of origin.

nutrients flowing into an area

A chemical intended to kill insects and other organisms that damage crops.

The measurement of how acidic or basic a substance is, on a scale of 0 (very acidic) to 14 (very basic).

A specific source of pollution that can be identified.

A substance that causes pollution.

A flat, white disc lowered into the water by a rope until it is just barely visible. At this point, the depth of the disc from the water surface is the recorded secchi disc transparency.

responsibility for conserving and restoring the Earth's resources for future generations

water that runs into drains that may contain sewage and chemicals from homes and businesses or pollutants from industry

The addition of any substance that has a negative effect on water or the living things that depend on the water.

The degree of purity of water, determined by measuring the substances in water besides water molecules.