Phosphorus

Phosphorus accumulation in U.S. farmland has become a major environmental concern because excess phosphorus from fertilizers and manure enters water bodies, causing serious water pollution. While phosphorus is essential for plant growth, overapplication leads to harmful ecological impacts.
Source of accumulation: Intensive use of phosphorus-based fertilizers and livestock manure adds more phosphorus to soils than crops can absorb.
Eutrophication: High phosphorus levels promote algal blooms that reduce oxygen in water, harming fish and other aquatic life.
Water quality impacts: Algal toxins contaminate drinking water and increase treatment costs.
Long-term effects: Phosphorus persists in soils and sediments, making pollution difficult and slow to reverse.