Phosphate
Phosphate (P) is a macronutrient essential for the survival and growth of organisms in aquatic systems . High concentrations of P are found in agricultural fertilizers, manure and organic wastes in sewage effluent. In freshwater P is generally considered the main 'limiting nutrient' and thus excessive inputs often leads to eutrophication. Therefore, the Water Framework Directive stipulates that P inputs, from both diffuse and point sources, need to be tightly controlled.
