A preliminary evaluation of Chatham Rise phosphorite as a direct-use phosphatic fertiliser.

Abstract In a glasshouse experiment using four soils the effectiveness of Chatham Rise phosphorite (CRP), in both powdered and pelletised form, as a source of P to ryegrass plants was compared to that of ‘granulated’ single superphosphate. The magnitude of the response to applied P varied between the soils. The type of fertiliser, its physical form, the method and rate of application, and time also influenced the response to applied P. Overall, powdered CRP was as effective as superphosphate in increasing ryegrass yields. When compared at 90% of the yield maxima of surface-applied superphosphate (taken as 100), the relative values for surface-applied powdered CRP were 96, 99, and 100 for Ramiha, Kumeroa, and Wainui soils respectively. Incorporation increased relative values to 100 and 106 on Ramiha and Wainui soils respectively. Pelletising reduced the overall performance of the CRP in supplying P to the plant to only a small extent. For surface-applied pelletised CRP the relative values were 85, 93, 93, ...

[1]  W. Horwitz.  Official Methods of Analysis , 1980 .

[2]  E. C. Doll,et al.  The Use of Phosphate Rock for Direct Application to Soils , 1979 .

[3]  J. Syers,et al.  STABILITY OF FERRIC PHOSPHATES , 1978 .

[4]  S. Chien,et al.  A Simple Chemical Method for Evaluating the Agronomic Potential of Granulated Phosphate Rock1 , 1978 .

[5]  J. Syers,et al.  ORIGIN OF THE LABILE PHOSPHATE POOL IN SOILS , 1977 .

[6]  C. Summerhayes,et al.  Sequential deposition of authigenic marine minerals around New Zealand: Paleoenvironmental significance , 1975 .

[7]  J. Syers,et al.  Comparison of Methods for the Determination of Total Phosphorus in Waters Containing Particulate Material 1 , 1975 .

[8]  O. Roberts,et al.  Some factors affecting agronomic response to apatites and to calcined Christmas Island iron/aluminium phosphates , 1974 .

[9]  P. J. Stangel,et al.  Tailoring of fertilizers for rice , 1972 .

[10]  C. Williams,et al.  The determination of phosphorus in Kjeldahl digests of plant material by automatic analysis , 1971 .

[11]  F. Muller.  Agronomic use of calcined christmas island iron/aluminium phosphates i. field trials , 1970 .

[12]  C. Woodruff,et al.  Dissolution and Availability to Plants of Rock Phosphates of Igneous and Sedimentary Origins , 1968 .

[13]  W. Saunders.  Phosphate retention by New Zealand soils and its relationship to free sesquioxides, organic matter, and other soil properties , 1965 .

[14]  D. Peaslee,et al.  Estimation of Relative Value of Phosphate Rock and Superphosphate to Plants on Different Soils1 , 1962 .

[15]  J. P. Riley,et al.  A modified single solution method for the determination of phosphate in natural waters , 1962 .

[16]  E. Truog,et al.  Rock Phosphate Availability as Influenced by Soil pH , 1955 .