Accumulation of plant nutrients and changes in soil properties of sandy soils under fertilized pasture in southeastern South-Australia .I. Phosphorus

The accumulation of phosphorus applied as superphosphate over a 25-year period to pastures growing on sand over clay soils was measured in three areas of different rainfall in the south-east of South Australia. Total soil phosphorus levels increased in the 0-10 cm, 10-30 cm and 30 cm-clay layers for all areas, but no accumulation occurred in the clay layer. For every 100 kg ha-1 of single superphosphate (9.6% phosphorus) applied, 2.0, 3.2 and 3.5 kg ha-1 of phosphorus accumulated in the 0-10 cm layer for the Hundreds of Coles, Willalooka and Senior respectively. The recoveries of applied phosphorus in the sand layer for the three areas were 42, 57 and 75% for Coles, Willalooka and Senior respectively. The annual accumulation rates of organic phosphorus in the top 30 cm of soil ranged from 2.4 to 3.5 kg ha-1. By using a 'balance sheet' approach, the annual maintenance phosphate requirements for the three areas were calculated. These ranged from 60 to 165 kg ha-1 of superphosphate, and were associated with differences in leaching losses, stocking rates and organic phosphorus accumulation.

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An attempted fractionation of the soil phosphorus

The Journal of Agricultural Science ◽

10.1017/s0021859600050644 ◽

1938 ◽

Vol 28 (2) ◽

pp. 234-246 ◽

Cited By ~ 44

Author(s):

L. A. Dean

Keyword(s):

Sodium Hydroxide ◽

Organic Phosphorus ◽

Soil Phosphorus ◽

Inorganic Phosphorus ◽

Soil Extracts ◽

Soil Calcium ◽

Soluble Phosphorus ◽

Total Soil Phosphorus ◽

Continued Use ◽

Phosphatic Fertilizers

1. Extractions of soils with sodium hydroxide, followed by an acid, have been used in an attempt to fractionate the soil phosphorus.2. Colorimetric methods for the estimation of the organic and inorganic phosphorus in alkali soil extracts have been suggested.3. The amount of soil phosphorus soluble in sodium hydroxide is affected by the active soil calcium. It is suggested that sodium-saturated soils be used when studying the alkali-soluble phosphorus.4. The acid-soluble phosphorus remaining in soil after extraction with sodium hydroxide was determined. This fraction appears by analogy to be similar to the apatites.5. The largest fraction of the total soil phosphorus was not dissolved by the sodium hydroxide and acid extractions. This fraction was not increased by the long-continued use of phosphatic fertilizers at Rothamsted and Woburn.6. Relatively large amounts of organic phosphorus were found in soils and the amounts were closely related to the carbon contents.

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Changes in bicarbonate-extractable phosphorus of a basalt-derived duplex soil associated with applications of superphosphate to pasture grazed by sheep

Australian Journal of Agricultural Research ◽

10.1071/a98037 ◽

1999 ◽

Vol 50 (4) ◽

pp. 547 ◽

Cited By ~ 5

Author(s):

J. W. D. Cayley ◽

G. A. Kearney

Keyword(s):

Perennial Ryegrass ◽

Empirical Model ◽

Soil Phosphorus ◽

Subterranean Clover ◽

Single Superphosphate ◽

Olsen P ◽

Current Value ◽

Stocking Rates ◽

Similar Soil ◽

Extractable Soil

The effect of 3 successive yearly applications of single superphosphate (SSP) to pastures on bicarbonate- extractable soil phosphorus (Olsen P) was measured. The soil was a duplex derived from basalt and the pastures, based on perennial ryegrass and subterranean clover, were continuously stocked with sheep. Six levels of SSP were compared at 3 stocking rates. The amount of P applied annually varied from 0 to 100 kg/ha. These data were used to create an empirical model which used the current value for Olsen P (Olsen Pn), the amount of P applied as fertiliser that year (fert Pn), and a lower limit for Olsen P for basalt-derived duplex soils (Olsen Plow) to predict the Olsen P for the following year (Olsen Pn+1). The model had the form: Olsen Pn+1 = Olsen P low + afert Pn + b(Olsen Pn – Olsen Plow). Olsen P low was fixed at 3 mg P/kg soil, and the coefficients a and b were 0.0995 and 0.8020. The model accounted for 96.6% of the variance in Olsen Pn+1. This model was tested at the same site at 2 other periods: when fertiliser was withheld for 3 years and again after applications of SSP were resumed. The model was also tested against data from another experiment conducted on a similar soil. The model can estimate the amount of fertiliser required to maintain the P status of the soil and predicts that to increase Olsen P by 1 unit in the following year it is necessary to apply 10 kg P/ha in excess of soil maintenance requirement.

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PHOSPHORUS FRACTIONS IN A SOIL SAMPLED AT DIFFERENT DEPTHS AND THE EFFECT OF LIME AND FERTILIZER ON OATS AND CLOVER IN A GREENHOUSE TEST

Canadian Journal of Soil Science ◽

10.4141/cjss60-009 ◽

1960 ◽

Vol 40 (1) ◽

pp. 71-79

Author(s):

H. A. Hamilton ◽

J. R. Lessard

Keyword(s):

Surface Soil ◽

Crop Yields ◽

Organic Phosphorus ◽

Soil Phosphorus ◽

Phosphate Fertilizer ◽

Iron Phosphate ◽

Soil Layers ◽

Surface Samples ◽

Different Depths ◽

Total Soil Phosphorus

Soil samples were collected at four different depths from a virgin soil, and in a region where deep ploughing has been a common practice. Chemical analyses revealed that the sub-surface samples were more highly saturated with bases than were the surface samples. In the 0–6 inch layer the percentage contribution of calcium, aluminium and iron phosphate to total soil phosphorus was 41.1, 10.4 and 2.8 respectively; while, in the 18–24 inch layer the percentages were 88.4, 2.8 and 0.5 respectively. Organic phosphorus decreased with depth.In the greenhouse there were highly significant differences between oat yields on the various layers, the surface soil giving the highest yields. Clover crop yields tended to be better as depth of profile increased. Phosphorus increased oat yields and clover yields on all soil layers. As a result of over-liming in certain instances clover yields were depressed in the absence of applied phosphate fertilizer, whereas oat yields were unaffected.

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Prediction of yield responses to phosphorus by established Greenleaf desmodium/grass pastures in south-east Queensland using chemical tests

Australian Journal of Experimental Agriculture ◽

10.1071/ea9800477 ◽

1980 ◽

Vol 20 (105) ◽

pp. 477

Author(s):

GE Rayment ◽

RC Bruce ◽

BG Cook

Keyword(s):

Soil Phosphorus ◽

Residual Variance ◽

Total Soil ◽

Plant Chemical ◽

Diagnostic Samples ◽

Total Soil Phosphorus ◽

Independent Variable ◽

Phosphorus Status ◽

Yield Responses ◽

Phosphorus Levels

Phosphorus topdressing experiments (rates to 60 kg P ha-1) on 18 commercial Desmodium intortum cv. Greenleaf/grass pastures were conducted over a 4-year period in south-east Queensland. The aim was to determine whether yield responses, which occurred only in the Greenleaf component at six sites, could be predicted using soil or plant chemical tests. Acid-(0.005 M H2SO4) and bicarbonate-(0.5 M NaHCO3) extractable tests of phosphorus status in 0-10 cm soil samples each explained about 60% of the variance in Greenleaf relative yields. The residual variance was not significantly reduced by the inclusion of terms for total soil nitrogen, total soil phosphorus, exchangeable calcium and pH into the independent variable. These empirical soil phosphorus tests had higher predictive value than plant tests based on phosphorus concentrations in tops and diagnostic samples of Greenleaf. With both acid- and bicarbonate-extractable phosphorus, yield responses are likely in the Greenleaf component when phosphorus levels in most soils are below 22 ppm. Above 29 ppm, no response would be expected

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Accumulation of plant nutrients and changes in soil properties of sandy soils under fertilized pasture in southeastern South-Australia .II. Total sulfur and nitrogen, organic carbon and pH

Soil Research ◽

10.1071/sr9870203 ◽

1987 ◽

Vol 25 (2) ◽

pp. 203 ◽

Cited By ~ 20

Author(s):

DC Lewis ◽

AL Clarke ◽

WB Hall

Keyword(s):

Organic Carbon ◽

Balance Sheet ◽

South Australia ◽

Annual Rainfall ◽

Nitrogen Accumulation ◽

Total Sulfur ◽

Accumulation Rates ◽

Single Superphosphate ◽

Highly Correlated ◽

Pasture Age

The accumulation of total sulfur in sand over clay soils growing improved pastures was measured in three areas of the south-east of South Australia. Accumulation rates in the top 10 cm of soil ranged from 4.6 to 6.3 kg ha-1 yr-1 and in the 10-30 cm layer from 1.3 to 3.7 kg ha-1 yr-1. Assuming all of this sulfur came from applied single superphosphate, the recoveries of applied sulfur in the sand layer were 42, 63 and 57% for the Hundreds of Coles, Willalooka and Senior respectively. Using a 'balance sheet' approach, the calculated annual maintenance superphosphate rates, that will supply sufficient sulfur, ranged from 110 to 250 kg ha-1. Total soil nitrogen accumulation rates were 55, 48 and 37 kg ha-1 yr-1 for the Hundreds of Coles, Willalooka and Senior respectively. The enhanced nitrogen accretion in Coles was attributed to improved legume production resulting from both increased superphosphate dressings and higher average annual rainfall in that area. Organic carbon levels were highly correlated with pasture age, with increases in the top 10 cm of soil ranging from 0.022% to 0.034% per year. Soil pH was highly correlated with pasture age, with decreases as large as 0.036 units per year in the top 10 cm and 0.025 units per year in the 10-30 cm layer measured in the Hundred of Willalooka.

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Phosphate responses in relation to soil tests and organic phosphorus

The Journal of Agricultural Science ◽

10.1017/s0021859600021274 ◽

1960 ◽

Vol 54 (3) ◽

pp. 341-347 ◽

Cited By ~ 33

Author(s):

M. T. Friend ◽

H. F. Birch

Keyword(s):

Organic Phosphorus ◽

Soil Phosphorus ◽

Inorganic Phosphorus ◽

Soil Extract ◽

Water Soluble ◽

Phosphorus Fraction ◽

Retention Capacity ◽

Phosphate Retention ◽

Total Soil Phosphorus ◽

Phosphate Response

Phosphate responses of wheat in a number of soil types have been correlated with the amounts of phosphate extracted by ten different methods. Of these only total organic phosphorus, and inorganic phosphorus extracted with hot 0·1N caustic soda, were significantly related to phosphate response, the former at the 1% level and the latter at the 5% level. The amount of organic phosphorus in the soil was also found to be significantly related, in each instance at the 5% level, to phosphate responses of grass and the percentage phosphate in the grass. When the amount of organic phosphorus was considered together with the phosphate retention capacity of the soil, to give a measure of available mineralized phosphate, the relationships to response (and uptake of phosphorus by grasses) was more significant than with organic phosphorus alone.The organic phosphorus fraction accounted for about 86% of the total soil phosphorus. Measurable amounts of water-soluble organic phosphorus were found with all the soils. The amounts were, however, not significantly related to phosphate response. Moreover, it was found that while the soil extract containing organic phosphorus decomposed, it did so without the production of mineral phosphate. From this, and further evidence in the literature, it is considered that the organic complex in the soil, rather than the water soluble phosphorus, is the main source for the plant.

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Effects of Soil Conditioners on Absorption of phosphorus by waxy corn and Phosphorus Transformation in High Phosphorus Soils

E3S Web of Conferences ◽

10.1051/e3sconf/202014302024 ◽

2020 ◽

Vol 143 ◽

pp. 02024

Author(s):

Wang Xi ◽

Lu Shuchang ◽

Pei Zhiqiang ◽

Hou Kun ◽

Ya Zongjie ◽

...

Keyword(s):

Humic Acid ◽

Total Phosphorus ◽

Phosphorus Content ◽

Organic Phosphorus ◽

Soil Phosphorus ◽

Inorganic Phosphorus ◽

Total Phosphorus Content ◽

The Third ◽

Phosphorus Accumulation ◽

Waxy Corn

In this experiment, the effects of different types of conditioners and their application on the absorption and transformation of phosphorus in high phosphorus soils in facilities were investigated to improve the environmental problems of protected farmland caused by phosphorus accumulation. Waxy corn was used as a test crop, and five conditioners such as humic acid, biochar, bentonite, alum, and dephosphorized gypsum were used as test materials for potting experiments. The experiment set 10 treatments, namely T1(Blank control), T2(Humic acid), T3(Biochar), T4(Bentonite), T5(Alum), T6 (Dephosphorized gypsum), T7(Biochar-bentonite-alum), T8(Humic acid-biochar-alum),T9(Humic acidbiochar- bentonite-alum),T10(Humic acid-bentonite-biochar-alum-dephosphorized gypsum). Based on the analysis of the results of the three crops, except that the first crop was not significant, the biomass and phosphorus absorption of waxy corn of T2 was the highest in the second crop, and T10 was the most effective treatment in the third crop. The soil available phosphorus content of T8 was the lowest in the second crop and that of T10 was the lowest in the third crop, which were 12.01% and 12.75% lower than the control. The soil water-soluble phosphorus content of T4 was the lowest in the second crop, which was 41.84% lower than the control, and that of T8 was the lowest in the third crop, which was 26.62% lower than the control. According to the results of the three crops, the ratio of the total phosphorus content of the inorganic phosphorus in the third crop of each treatment was increasing compared with the first crop. The soil phosphorus was transformed from organic phosphorus to inorganic phosphorus. The ratio of total phosphorus content of organic phosphorus of T6, T9, T10 was larger than other treatments, which slowed down the conversion of phosphorus to available form. The ratio of Ca8-P in the inorganic phosphorus was the highest, reaching about 50% to 60%. From the results and analysis, T2 and T10 were beneficial to the absorption of soil phosphorus by waxy corn, T8 and T10 were beneficial to slow down the conversion of phosphorus to the effective state, reduce the potential risk of phosphorus environment, improve the phosphorus accumulation environmental issues in greenhouse farmland.

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