Total Phosphorus

A nutrient essential to the growth of organisms, and is commonly
the limiting factor in the primary productivity of surface water
bodies. Total phosphorus includes the amount of phosphorus in
solution (reactive) and in particle form. Agricultural drainage,
wastewater, and certain industrial discharges are typical sources
of phosphorus, and can contribute to the eutrophication of
surface water bodies. Measured in milligrams per liter (mg/L).