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Glossary beginning with N

terms for which definitions are available


National Oceanic and Atmospheric Administration

non-point source pollution

pollution that comes from a diffuse source such as atmospheric deposition, stormwater runoff from pasture and cro pland, or individual on-lot domestic sewage systems discharging through shallow groundwater


National Pollutant Discharge Elimination System


an element or molecule needed for biological growth; when nutrients such as phosphorus are present in great concentrations, biological growth (algae in particular) can become overabundant, causing problems for aquatic ecosystems