ABSTRACT

Phosphorus fertilizers contain cadmium (Cd) as a contaminant at levels varying from trace amounts to as much as 300 mg Cd kg−1 of dry product and therefore can be a major source of Cd input to agricultural systems. Cd will accumulate in the soils if the amount added in fertilizer is greater than what is removed by crop harvest or through other loss pathways such as erosion, bioturbation, or leaching. Phosphate fertilizer may also inuence Cd phytoavailability through fertilizer-induced changes in soil pH, osmotic strength of the soil solution, zinc (Zn) availability, soil organic matter, rhizosphere chemistry, soil microbial activity, and plant growth. As both total Cd input into the soil and fertilizer-induced changes in soil properties are a function of the rate of fertilizer application, management practices that improve fertilizer use efciency should be adopted to minimize fertilizer inputs while maintaining crop yield potential.