Implications of long-term superphosphate applications on the accumulation and plant availability of soil phosphorus under irrigated pastures
Changes in soil phosphorus (P) associated with the establishment and maintenance of improved ryegrass-clover pasture under different superphosphate fertiliser treatments were examined over a 20-year period (1957-77). Results showed that soil organic P increased with increasing applications of P fertiliser. This represents a dynamic balance between rates of organic P addition and breakdown in the soil. This balance is reached slowly and may be significantly altered only by drastic changes in land use. In annually fertilised soils, amounts of inorganic P increased with time. However, the potential utilisation of this residual inorganic P is limited by its apparent stability in the soil.... [Show full abstract]
Keywordsfertiliser; grazed pasture; irrigation; soil organic P; soil P fractionation; soil inorganic P
TypeConference Contribution - Published (Conference Paper)
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