United States Department of Agriculture - Agricultural Research Service
	Northwest Irrigation & Soils Research Lab,  Kimberly, ID
	Glossary

Algae:                 Small aquatic plants

Aquatic:             Pertaining to water

Biological oxygen
demand:             (BOD) The rate of oxygen consumption by organisms during the decomposition of
                            organic matter, expressed as grams oxygen per cubic meter of  water per hour.

Contaminant:     Any physical, chemical, biological, or radiological substance or matter that has an
                            adverse effect on air, water, or soil.
 
Compost:            n: A mixture that consists largely of decayed and dried organic matter and is used for
                            fertilizer. vt: To convert (plant debris or manure) to compost.

Discharge:       (1) Any spilling, leaking, emitting, escaping, leaching, or disposing of a pollutant into
                                the waters of the State.
                           (2) The release of any waste into the environment from a point source; Usually refers
                                to release of a liquid waste into a water body through an outlet such as a pipe.
                           (3) The amount of water flowing in the stream channel at the time of measurement;
                                usually expressed as cubic feet per second (cfs).

Dissolved oxygen: (DO) Amount of oxygen dispersed in the water and is usually expressed as mg/L.

Drainage:           The surface or sub-surface water derived within a clearly defined catchment area.

Ecology:             Scientific study of relationships between organisms and their environment

Ecosystem:        The interacting system of biological community and its nonliving environmental
                            surroundings.

Effluent:             Wastewater discharged from a point source such as a pipe

Environment:     The sum of all external conditions affecting the life, development and survival of an
                            organism.

Erosion:             The wearing away of the land surface by running water, wind, ice, gravity or other
                            geological phenomena.

Eutrophication: The process by which a body of water becomes either naturally or by pollution rich in
                            dissolved nutrients (as phosphates) and often shallow with a seasonal deficiency in
                            dissolved oxygen.

Habitat:             Those parts of the environment on which an organism depends, directly or indirectly,
                            in order to carry out its life processes.

Limnology:         Study of fresh water including organisms, biology and chemistry.

Manure:             Refuse of stables and barnyards composed of livestock excreta with or without litter
                            (straw or sawdust), used to fertilize land.

Nonpoint source: Pollution that is not released through pipes but rather originates from multiple
                             sources over a relatively large area.

Nitrogen:            An element that occurs in various chemical forms. It makes up 78% of our atmosphere
                            and is required for growth of plants and animals in protein. It is a common fertilizer
                            component used for crop production. Gaseous nitrogen (N₂ ) in atmosphere can not
                            be used by plants or animals until it is converted by nitrogen-fixing organisms,
                            associated with legumes, to forms available to higher plants.

Nutrient:             Element or chemical essential to life, such as carbon, oxygen, nitrogen, and
                            phosphorus.

Phosphorus:        An element required for growth of plants and animals where it is found in ATP and
                            bones. It is one of the commonly applied fertilizer elements, and as an ingredient in
                            detergents and soaps. It is a mined product.

Point source:     Pollution that is discharged from any identifiable point including pipes, ditches,
                            sewers etc.

Pollutant:            Any substance introduced into the environment that adversely affects the
                            usefulness of a resource.

Pollution:            (1) The man-made or man-induced alteration of the chemical, physical, biological,
                                and radiological integrity of water.
                            (2) Any alteration in the character or quality of the environment that renders it unfit
                                or less suited for beneficial uses.

Potassium:         Element that is required for growth of plants and animals. It is a mined product.

Riparian vegetation: Vegetation that is associated with aquatic streams, river, and lakes.

Runoff:                The part of precipitation and snowmelt that reaches streams by flowing over or
                            through the ground; surface runoff flows away without penetrating the soils.

Sediment:            Soil particles that enter the water from erosion of land.

Septic system:     A contained system for decomposing of human, animal or industrial wastes where
                            discharge is generally allowed to infiltrate into the ground.

Sewage:             The waste and wastewater produced by residential and businesses and discharged
                            into sewers.

Total suspended
solids (TSS):     The material retained on a 45 micron filter after filtration. Equivalent to 0.002 inches

Total maximum daily
load (TMDL):     The total amounts of a particular pollutant that sources can discharge without
                            violating water quality standards.

Waste:                 A resource out of place.

Water pollution:  The man-made or human-induced alteration of the chemical, physical, biological
                              or radiological integrity of water

Water quality:    This is a defined characteristic. Several categories dependant upon designated use.
                            Drinking water, Livestock use, irrigation. Quality is defined or legislated.

Water table: The upper surface of groundwater; below this point, the soil or rock is saturated with
                            water.

Wetlands:         Those areas that are soaked or flooded by surface or ground water frequently enough or
                           for sufficient duration to support plants, birds, animals, and aquatic life.