A Monitor's Guide to Water Quality


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Naturally occurring nitrate (NO3) concentrations in lakes and streams are typically less than 4 mg/L, and the concentration of nitrite (NO2) is generally much lower. The concentration of ammonia (NH3) in natural waters is generally less than 0.1 mg/L.

How is it measured?

Nitrogen is measured from a water sample sent to the lab. The sample may or may not be filtered before analysis. It is important to know what form of nitrogen is being measured, because the more bioavailable inorganic forms (nitrate, nitrite and ammonia/ammonium) behave differently and have different impacts on water quality compared to organic forms.

Related to nitrogen : water colour, total suspended solids (TSS)

Nitrogen influences : chlorophyll