Technical Bulletin No. 0879: Biodegradability of Organic Nitrogen and Phosphorus in Pulp Mill Effluents

Nitrogen and phosphorus play critical roles in the growth and maintenance of plants and animals, but excessive amounts of these elements in the aqueous environment can contribute to degraded water quality. These elements exist in nature in both organic and inorganic forms, but only inorganic forms such as ammonium, nitrite, nitrate, and orthophosphate are considered to be directly assimilable by organisms. Some of the nitrogen and phosphorus in biologically treated effluents is associated with organic matter, a portion of which is biologically inert humic material.