The agronomic effectiveness of reactive phosphate rocks 4. Early season lag in herbage production when reactive phosphate rock is used as a pasture fertiliser

1997 ◽  
Vol 37 (8) ◽  
pp. 957 ◽  
Author(s):  
D. Johnson ◽  
P. W. G. Sale ◽  
P. G. Simpson ◽  
J. W. D. Cayley
Keyword(s):  
Phosphate Rock ◽  
Growing Season ◽  
Seasonal Effects ◽  
Seasonal Effect ◽  
Yield Reduction ◽  
Lag Phase ◽  
Agronomic Effectiveness ◽  
Early Season ◽  
Reactive Phosphate ◽  
Reactive Phosphate Rock

Summary. The agronomic effectiveness of highly reactive North Carolina phosphate rock (NCPR), relative to triple superphosphate (TSP), was determined for individual harvests at 26 permanent pasture sites in the National Reactive Phosphate Rock Project from 1992 to 1995. The aim was to determine whether the performance of NCPR relative to TSP was consistent over the growing season. Poor performance of NCPR early in the growing season (early seasonal lags), and its subsequent improvement later in the season, was observed at 15 of the 26 sites in this project and for 20 of the 103 possible site x year combinations. At 3 additional sites the apparent early season lag in NCPR performance was followed by harvests where there was no phosphorus (P) response. At one P-leaching site with a long growing season the relative yields from NCPR plots increased as the year progressed and exceeded those from TSP late in th e season. The duration of the early season lag phase was associated with the rate of build-up in plant-available P over the 4-year duration of the trials. The lag disappeared after 1 or 2 years at sites with low P-sorbing, sandy soils where there was a significant build-up in Colwell P, but persisted for 4 years on high P-sorbing soils where limited increases in Colwell P occurred. The average early season yield reduction associated with use of NCPR, compared with using TSP, was 28%. Colwell soil test values alone did not provide a good indication of the likelihood of a seasonal effect occurring. The occurrence of an early season lag phase needs to be taken into account by farmers considering the use of RPR as reductions in feed supply at this time of the year have the potential to reduce stocking rates and farm profitability. The use of partially acidulated NCPR, or large applications of NCPR applied in the first year, were management strategies that minimised the occurrence of these seasonal effects. The suggestion that the early season lag effect is due to the inability of NCPR to meet P demands from newly establishing pasture legumes, and increased P requirements by pasture plants in cold conditions is also discussed.

The agronomic effectiveness of reactive phosphate rocks 1. Effect of the pasture environment

1997 ◽  
Vol 37 (8) ◽  
pp. 921 ◽  
Author(s):  
P. W. G Sale ◽  
R. J. Gilkes ◽  
M. D. A. Bolland ◽  
P. G. Simpson ◽  
D. C. Lewis ◽  
...  
Keyword(s):  
North Carolina ◽  
Phosphate Rock ◽  
Surface Soil ◽  
Annual Rainfall ◽  
Triple Superphosphate ◽  
Agronomic Effectiveness ◽  
P Sorption ◽  
Reactive Phosphate ◽  
Reactive Phosphate Rock ◽  
Very High

Summary. The agronomic effectiveness of directly applied North Carolina reactive phosphate rock was determined for 4 years from annual dry matter responses at 26 permanent pasture sites across Australia as part of the National Reactive Phosphate Rock Project. Fertiliser comparisons were based on the substitution value of North Carolina reactive phosphate rock for triple superphosphate (the SV50). The SV50 was calculated from fitted response curves for both fertilisers at the 50% of maximum yield response level of triple superphosphate. The reactive phosphate rock was judged to be as effective as triple superphosphate in the 1st year (and every year thereafter) at 4 sites (SV50 >0.9), and was as effective by the 4th year at 5 sites. At another 9 sites the reactive phosphate rock was only moderately effective with SV50 values between 0.5 and 0.8 in the 4th year, and at the final 8 sites it performed poorly with the 4th year SV50 being less than 0.5. Pasture environments where the reactive phosphate rock was effective in the 1st year were: (i) those on sandy, humic or peaty podsols with an annual rainfall in excess of 850 mm; (ii) those on soils that experienced prolonged winter inundation and lateral surface flow; and (iii) tropical grass pastures in very high rainfall areas (>2300 mm) on the wet tropical coast on North Queensland. The highly reactive North Carolina phosphate rock became effective by the 4th year at sites in southern Australia where annual rainfall exceeded 700 mm, and where the surface soil was acidic [pH (CaCl2) <5.0] and not excessively sandy (sand fraction in the A1 horizon <67%) but had some phosphorus (P) sorption capacity. Sites that were unsuitable for reactive phosphate rock use in the medium term (up to 4 years at least) were on very high P-sorbing krasnozem soils or high P-sorbing lateritic or red earth soils supporting subterranean-clover-dominant pasture, or on lower rainfall (< 600 mm) pastures growing on soils with a sandy A1 horizon (sand component >84%). No single environmental feature adequately predicted reactive phosphate rock performance although the surface pH of the soil was most closely correlated with the year-4 SV50 (r = 0.67). Multiple linear regression analysis found that available soil P (0–10 cm) and the P sorption class of the surface soil (0–2 cm), together with annual rainfall and a measure of the surface soil"s ability to retain moisture, could explain about two-thirds of the variance in the year-4 SV50 . The results from this Project indicate that there are a number of specific pasture environments in the higher rainfall regions of Australia where North Carolina reactive phosphate rock can be considered as an effective substitute P fertiliser for improved pasture.

National Reactive Phosphate Rock Project —aims, experimental approach and site characteristics

1997 ◽  
Vol 37 (8) ◽  
pp. 885 ◽  
Author(s):  
M. J. McLaughlin ◽  
N. K. Fleming ◽  
P. G. Simpson ◽  
M. D. A. Bolland ◽  
R. J. Gilkes ◽  
...  
Keyword(s):  
North Carolina ◽  
Formic Acid ◽  
Phosphate Rock ◽  
Soil Phosphorus ◽  
Triple Superphosphate ◽  
Phosphate Rocks ◽  
Agronomic Effectiveness ◽  
North Carolina Phosphate Rock ◽  
Reactive Phosphate ◽  
Reactive Phosphate Rock

Summary. Field-based cutting trials, which formed part of the National Reactive Phosphate Rock Project, were established across Australia in a range of environments to evaluate the agronomic effectiveness of 5 phosphate rocks, and 1 partially acidulated phosphate rock, relative to either single superphosphate or triple superphosphate. The phosphate rocks differed in reactivity. Sechura (Bayovar) and North Carolina phosphate rocks were highly reactive (>70% solubility in 2% formic acid), whilst Khouribja (Moroccan) and Hamrawein (Egypt) phosphate rock were moderately reactive. Duchess phosphate rock from Queensland was relatively unreactive (<45% solubility in 2% formic acid). Phosphate rock effectiveness was assessed by measuring pasture production over a range of phosphorus levels, and by monitoring bicarbonate-soluble phosphorus extracted from soil samples collected before the start of each growing season. Other treatments included single large applications of triple superphosphate, partially acidulated phosphate rock and North Carolina phosphate rock applied at 2 rates, and the application of monocalcium phosphate and North Carolina phosphate rock sources without sulfur to evaluate the importance of sulfur in the potential use of phosphate rock fertilisers at each site. A broad range of environments were represented over the 30 sites which were based on pastures using annual and/or perennial legumes and perennial grasses. Rainfall across the network of sites ranged from 560 to 4320 mm, soil pH (CaCl2) from 4.0 to 5.1, and Colwell-extractable phosphorus ranged from 3 to 47 µg/g before fertiliser application. Two core experiments were established at each site. The first measured the effects of phosphate rock reactivity on agronomic effectiveness, while the second measured the effects of the degree of water solubility of the phosphorus source on agronomic effectiveness. The National Reactive Phosphate Rock Project trials gave the opportunity to confirm the suitability of accepted procedures to model fertiliser response and to develop new approaches for comparing different fertiliser responses. The Project also provided the framework for subsidiary studies such as the effect of fertiliser source on soil phosphorus extractability, cadmium and fluorine concentrations in herbage, evaluation of soil phosphorus tests, and the influence of particle size on phosphate rock effectiveness. The National Reactive Phosphate Rock Project presents a valuable model for a large, Australia-wide, collaborative team approach to an important agricultural issue. The use of standard and consistent experimental methodologies at every site ensured that maximum benefit was obtained from data generated. The aims, rationale and methods used for the experiments across the network are presented and discussed.

Agronomic effectiveness of a partially acidulated reactive phosphate rock fertiliser

1997 ◽  
Vol 37 (8) ◽  
pp. 985 ◽  
Author(s):  
D. C. Lewis ◽  
P. W. G. Sale ◽  
D. Johnson
Keyword(s):  
North Carolina ◽  
Phosphate Rock ◽  
Agronomic Effectiveness ◽  
Permanent Pasture ◽  
North Carolina Phosphate Rock ◽  
Reactive Phosphate ◽  
Reactive Phosphate Rock ◽  
Papr Performance ◽  
Yield Responses ◽  
Very High

Summary. The agronomic effectiveness of a partially acidulated phosphate rock (PAPR), produced by the 50% acidulation of North Carolina phosphate rock with sulfuric acid, was compared over 4 growing seasons with triple superphosphate (TSP) and the highly reactive North Carolina phosphate rock at 22 permanent pasture sites in the National Reactive Phosphate Rock Project. The performance of PAPR as a phosphorus (P) fertiliser for permanent pasture was determined by calculating the substitution value of TSP for PAPR at 50% of the maximum yield response for TSP from the fitted annual dry matter response curves. PAPR performance varied both between sites, and between years at individual sites. Annual yield responses with PAPR were larger than those with TSP at 1 high rainfall site where water-soluble P from TSP was thought to leach from the root zone. PAPR was superior to TSP at another site and generally similar in effectiveness to TSP at 4 sites with light-textured, low or medium P-sorbing soils with a moderate annual rainfall (500–750 mm). The mean substitution value over the 4 years for these sites was >0.9. PAPR performance at other sites where highly reactive phosphate rocks were effective in the short or medium term was variable: there were equivalent yield responses to TSP in some years but much smaller yield responses in other years. PAPR performed very poorly in a third group of sites where the soil had a high to very high P sorption capacity or where there was a very high demand for fertiliser P due to large legume responses on a P-deficient soil. Although generally inferior to TSP, the PAPR was more effective than North Carolina phosphate rock at the majority of sites during the 4-year study.

The agronomic effectiveness of reactive phosphate rocks 5. The effect of particle size of a moderately reactive phosphate rock

1997 ◽  
Vol 37 (8) ◽  
pp. 969 ◽  
Author(s):  
A. M. Babare ◽  
P. W. G. Sale ◽  
N. Fleming ◽  
D. L. Garden ◽  
D. Johnson
Keyword(s):  
North Carolina ◽  
Particle Size ◽  
Phosphate Rock ◽  
Agronomic Effectiveness ◽  
Monocalcium Phosphate ◽  
Particle Size Fractions ◽  
North Carolina Phosphate Rock ◽  
Reactive Phosphate ◽  
Reactive Phosphate Rock ◽  
Effect Of Particle Size

Summary. The effect of particle size on the agronomic effectiveness of a moderately reactive phosphate rock (from the Hamrawein deposit in Egypt) was investigated at 4 of the field sites in the National Reactive Phosphate Rock Project. The aim of these experiments was to determine whether the agronomic effectiveness of this fertiliser was increased by removing particles greater than 0.5 mm in diameter (these coarser particles constituted 28% of the fertiliser). The more reactive North Carolina phosphate rock was used as a reference fertiliser. Soils from 3 of the field sites were also used for glasshouse experiments. The forms of Hamrawein phosphate rock used in these experiments were the less than 0.50 mm particle size fraction (as was used in the field experiments), the 0.075–0.15 mm fraction, and the less than 0.50 mm particle size fraction finely ground. Subterranean clover was used as the test plant and North Carolina phosphate rock and monocalcium phosphate were used as reference fertilisers. A series of laboratory experiments were also undertaken to investigate the effect of particle size. The agronomic effectiveness of Hamrawein phosphate rock was not affected by the different particle size treatments used in the field and glasshouse experiments. The Hamrawein phosphate rock was about equal in effectiveness to North Carolina phosphate rock at the high rainfall leaching site that had acidic sandy soil, and was less effective than North Carolina phosphate rock at the other 2 field sites. The Hamrawein phosphate rock was similar in effectiveness to North Carolina phosphate rock and monocalcium phosphate in the glasshouse experiments with the 2 low P-sorbing soils and was much less effective than North Carolina phosphate rock and monocalcium phosphate in the high P-sorbing soil. Laboratory studies found that there were minimal differences in the amount and rate of dissolution of different particle size fractions of the Hamrawein phosphate rock in moist incubated soil. Free carbonate, most likely in the form of dolomite, was found in all particle size fractions of the Hamrawein phosphate rock and was particularly concentrated in the particle size fractions less than 0.15 mm. This fine dolomite fraction may have suppressed the extent that Hamrawein phosphate rock dissolves in soil, and may have negated any potential beneficial effect that reducing particle size by sieving or by grinding may have had on the agronomic effectiveness of Hamrawein phosphate rock in the field and glasshouse experiments.

scholarly journals Direct application of reactive phosphate rock on improving maize yield in tidal swampland

2021 ◽  
Vol 648 (1) ◽  
pp. 012175
Author(s):  
A F Siregar ◽  
Husnain ◽  
I W Suastika ◽  
N P S Ratmini ◽  
I A Sipahutar ◽  
...  
Keyword(s):  
Phosphate Rock ◽  
Maize Yield ◽  
Direct Application ◽  
Reactive Phosphate ◽  
Reactive Phosphate Rock

Chemical effects in commercial and laboratory mixtures of ?reactive? phosphate rock and acidulated fertilisers

1992 ◽  
Vol 31 (1) ◽  
pp. 111-118 ◽  
Author(s):  
A. C. Braithwaite ◽  
A. C. Eaton ◽  
P. S. Groom
Keyword(s):  
Phosphate Rock ◽  
Chemical Effects ◽  
Reactive Phosphate ◽  
Reactive Phosphate Rock

scholarly journals Effect of reactive phosphate rock to corn on acid sulphate soil in South Kalimantan

2020 ◽  
Vol 484 ◽  
pp. 012093
Author(s):  
Wahida Annisa ◽  
Husnain ◽  
Fadjri Djufry
Keyword(s):  
Phosphate Rock ◽  
Acid Sulphate Soil ◽  
Acid Sulphate ◽  
Reactive Phosphate ◽  
Reactive Phosphate Rock

Partially acidulated reactive phosphate rock (PAPR) fertilizer and its reactions in soil

1991 ◽  
Vol 28 (3) ◽  
pp. 295-304 ◽  
Author(s):  
D. C. Golden ◽  
R. B. Stewart ◽  
R. W. Tillman ◽  
R. E. White
Keyword(s):  
Phosphate Rock ◽  
Reactive Phosphate ◽  
Reactive Phosphate Rock

Effects of Combinations of Triple Superphosphate and a Reactive Phosphate Rock on Yield and Phosphorus Uptake by Corn

1987 ◽  
Vol 51 (6) ◽  
pp. 1656-1658 ◽  
Author(s):  
S. H. Chien ◽  
F. Adams ◽  
F. E. Khasawneh ◽  
J. Henao
Keyword(s):  
Phosphate Rock ◽  
Phosphorus Uptake ◽  
Triple Superphosphate ◽  
Reactive Phosphate ◽  
Reactive Phosphate Rock
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