Translocation of long-term surface-applied fertilizer P and K into a grassland soil profile
On established forage stands, P and K fertilizers are generally applied by broadcasting on the surface of the soil. Even under ideal conditions, only a small portion of the applied P and K is taken up by forage crops. Although P and K are considered relatively immobile in soil, after long-term applications the unused fertilizer P and K may move downward into soil profile and may even pollute underground water, depending on soil type, climatic conditions and rate of applied P. Information is lacking on the extent of translocation of surface-broadcast P and K into soil profile from their long-term applications. The objectives of this study were to determine the effect of 30 annual surface-broadcast applications of N fertilizer on extractable P and K in grassland soil. To determine the translocation of surface-applied P fertilizer into soil profile 20 years after 10 annual applications to established bromegrass stands. To determine the translocation of surface-applied K fertilizer into soil profile after 14 annual applications to established bromegrass stands.
Soils and Crops Workshop