Relationship between Olsen P and Ammonium Lactate–Extractable P in Portuguese Acid Soils

This study compared phosphorus (P) speciation and the relationship between bicarbonate extractable (Olsen) P and 0.01 M CaCl2 extractable P (a measure of potentially mobile P) in soils from plots of the Park Grass experiment started in 1856 at IACR-Rothamsted, UK and with and without nitrogen as (NH4)2SO4 and with and without calcium carbonate (CaCO3, lime). A point, termed the change point, was noted in Olsen P, above which 0.01 M CaCl2-P increased at a greater rate per unit increase in Olsen P than below this point. Previous findings have shown a change point for soils with a pH>5.8 at 56 mg Olsen P/kg and at 120 mg Olsen P/kg for soils below this pH. Soils given (NH4)2SO4 annually since 1856 and with lime periodically since 1903 mostly had a pH between 3.7 to 5.7, some of these (NH4)2SO4 treated soils were limed to pH 6.5 and above from 1965. Irrespective of their pH in 1991/92 all the soils had a similar change point (120 mg Olsen P/kg) to that found for other soils with pH<5.8 (112 mg Olsen P/kg). In a laboratory study lasting 30 days, the addition of CaCO3 to acid soils from the field experiment that had received (NH4)2SO4 had a similar change point to soils with pH<5.8 irrespective of pH, suggesting soil P chemistry was controlled by the long period of soil acidity and this was not reversed by a short period at a higher pH. The effect of pH was attributed to the creation of P sorptive surfaces on aluminium precipitates compared with less acidic soils (pH>5.8) where there was less exchangeable Al to be precipitated. This was confirmed with solid-state 31P nuclear magnetic resonance, which indicated that for soils of similar total P concentration and pH, there was twice as much amorphous Al-P in soils given (NH4)2SO4 compared with those without. Changes in pH as a result of applications of (NH4)2SO4 or lime can greatly change the concentration of potentially mobile P due to the effects on Al solubility. Although there was less potentially mobile P in soils with pH<5.8 than in soils above this pH, it is usually advised in temperate regions to maintain soils about pH 6.5 for arable crops.

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Leaching of dissolved phosphorus from tile-drained agricultural areas

Water Science & Technology ◽

10.2166/wst.2016.158 ◽

2016 ◽

Vol 73 (12) ◽

pp. 2953-2958 ◽

Cited By ~ 6

Author(s):

H. E. Andersen ◽

J. Windolf ◽

B. Kronvang

Keyword(s):

Soil Layer ◽

High Concentration ◽

Measured Concentration ◽

Leaching Potential ◽

Dissolved Phosphorus ◽

Olsen P ◽

P Loss ◽

Tile Drains ◽

Extractable P ◽

Water Extractable

Abstract We investigated leaching of dissolved phosphorus (P) from 45 tile-drains representing animal husbandry farms in all regions of Denmark. Leaching of P via tile-drains exhibits a high degree of spatial heterogeneity with a low concentration in the majority of tile-drains and few tile-drains (15% in our investigation) having high to very high concentration of dissolved P. The share of dissolved organic P (DOP) was high (up to 96%). Leaching of DOP has hitherto been a somewhat overlooked P loss pathway in Danish soils and the mechanisms of mobilization and transport of DOP needs more investigation. We found a high correlation between Olsen-P and water extractable P. Water extractable P is regarded as an indicator of risk of loss of dissolved P. Our findings indicate that Olsen-P, which is measured routinely in Danish agricultural soils, may be a useful proxy for the P leaching potential of soils. However, we found no straight-forward correlation between leaching potential of the top soil layer (expressed as either degree of P saturation, Olsen-P or water extractable P) and the measured concentration of dissolved P in the tile-drain. This underlines that not only the source of P but also the P loss pathway must be taken into account when evaluating the risk of P loss.

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Overwinter changes in Olsen phosphorus in a 24-year crop rotation study in southwestern Saskatchewan

Canadian Journal of Soil Science ◽

10.4141/cjss93-012 ◽

1993 ◽

Vol 73 (1) ◽

pp. 123-128 ◽

Cited By ~ 3

Author(s):

C. A. Campbell ◽

R. P. Zentner

Keyword(s):

Cropping Systems ◽

Soil Testing ◽

Available Phosphorus ◽

Canadian Prairie ◽

Olsen P ◽

Extractable P ◽

P Fertilizer ◽

Soil Test P ◽

Nutrient Analyses ◽

Rotation Study

In the Canadian prairie, producers generally sample soils in the autumn for nutrient analyses, whereas calibration of crop responses has been made based on soils sampled in the spring prior to seeding. A recent report suggests that available phosphorus (P) in soil increases between autumn and spring. At Swift Current, Saskatchewan, we have monitored bicarbonate-extractable P (Olsen P) every autumn and spring for the past 24 years, in four cropping systems: continuous wheat (Cont W), fallow-wheat (F-W), and two fallow-wheat-wheat (F-W-W) rotations. The first three systems received nitrogen (N) and P each crop year, with one F-W-W rotation receiving only N. These data were analyzed to test the authenticity of the aforementioned observations. We found that although there were some apparent overwinter increases in Olsen P there were also some decreases. Further, because of the considerable variability in Olsen P, relatively few of the overwinter changes were significant (P = 0.10). Efforts to correlate the changes in Olsen P to overwinter temperature or precipitation were unsuccessful. We concluded that Saskatchewan soil testing laboratories need not make adjustments to P fertilizer recommendations to account for changes in overwinter soil test P levels. Key words: Soil testing, bicarbonate-extractable P, crop rotations, available P

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A comparison of some surface soil phosphorus tests that could be used to assess P export potential

Soil Research ◽

10.1071/sr06142 ◽

2007 ◽

Vol 45 (5) ◽

pp. 397 ◽

Cited By ~ 11

Author(s):

David Nash ◽

Murray Hannah ◽

Kirsten Barlow ◽

Fiona Robertson ◽

Nicole Mathers ◽

...

Keyword(s):

Organic P ◽

Soil Tests ◽

Soil P ◽

Olsen P ◽

P Sorption ◽

P Loss ◽

Extractable P ◽

Soil P Tests ◽

Total P ◽

Water Extractable

Phosphorus (P) exports from agricultural land are a problem world-wide and soil tests are often used to identify high risk areas. A recent study investigated changes in soil (0–20 mm), soil water and overland flow in 4 recently laser-graded (<1 year) and 4 established (laser-graded >10 years) irrigated pastures in south-eastern Australia before and after 3 years of irrigated dairy production. We use the results from that study to briefly examine the relationships between a series of ‘agronomic’ (Olsen P, Colwell P), environmental (water-extractable P, calcium chloride extractable P, P sorption saturation, and P sorption), and other (total P, organic P) soil P tests. Of the 2 ‘agronomic’ soil P tests, Colwell P explained 91% of the variation in Olsen P, and Colwell P was better correlated with the other soil tests. With the exception of P sorption, all soil P tests explained 57% or more of the total variation in Colwell P, while they explained 61% or less of Olsen P possibly due to the importance of organic P in this soil. Variations in total P were best explained by the organic P (85%), Calcium chloride extractable P (83%), water-extractable P (78%), and P sorption saturation (76%). None of the tests adequately predicted the variation in P sorption at 5 mg P/L equilibrating solution concentration. The results of this limited study highlight the variability between soil P tests that may be used to estimate P loss potential. Moreover, these results suggest that empirical relationships between specific soil P tests and P export potential will have limited resolution where different soil tests are used, as the errors in the relationship between soil test P and P loss potential are compounded by between test variation. We conclude that broader study is needed to determine the relationships between soil P tests for Australian soils, and based on that study a standard protocol for assessing the potential for P loss should be developed.

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Impacts of Phosphogypsum, Soluble Fertilizer and Lime Amendment of Acid Soils on the Bioavailability of Phosphorus and Sulphur under Lucerne (Medicago sativa)

Plants ◽

10.3390/plants9070883 ◽

2020 ◽

Vol 9 (7) ◽

pp. 883

Author(s):

Moussa Bouray ◽

Jim Moir ◽

Leo Condron ◽

Niklas Lehto

Keyword(s):

Medicago Sativa ◽

Acid Soils ◽

Low Fertility ◽

Dual Roles ◽

Olsen P ◽

Positive Effects ◽

Grassland Ecosystems ◽

Nitrogen Inputs ◽

Soluble Fertilizer ◽

Yield Responses

Legumes play critical dual roles in grazed grassland ecosystems; providing nitrogen inputs and high-quality feed for grazing livestock. However, many species fail to persist in acidic, low fertility soils. A glasshouse study was conducted to investigate the response of lucerne (Medicago sativa) to phosphogypsum (PG), lime and soluble P + S fertilizer (PS) application to two soils. Phosphorus and sulphur were applied through either PG (0, 1, 3 and 9 t ha−1) or P + S fertilizer at equivalent rates to PG. Both PG and PS were applied with or without lime, which was applied at 2 t ha−1. Yield and nutrient uptake of the lucerne was measured, while the soil was analyzed for pH, Olsen P and exchangeable aluminum. Yield responses were significantly different between the two soils. Maximum yields and P and S uptakes were obtained under PG 9 t ha−1 combined with lime. Exchangeable Al decreased in both soils under 1 ha−1 of PG compared with the control. At the highest rate, Olsen P increased by 8 and 6 mg kg−1 for PG and by 6 and 11 mg kg−1 for PS compared with the control for Glenmore and Molesworth soils respectively. Phosphogypsum showed positive effects on P and S bioavailability.

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The Olsen P method as an agronomic and environmental test for predicting phosphate release from acid soils

Nutrient Cycling in Agroecosystems ◽

10.1007/s10705-006-9066-2 ◽

2007 ◽

Vol 77 (3) ◽

pp. 283-292 ◽

Cited By ~ 52

Author(s):

Maria do Carmo Horta ◽

José Torrent

Keyword(s):

Acid Soils ◽

Phosphate Release ◽

Olsen P ◽

Environmental Test

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Nitrogen and Phosphorus Changes in Soil and Soil Water after Cultivation

Applied and Environmental Soil Science ◽

10.1155/2012/157068 ◽

2012 ◽

Vol 2012 ◽

pp. 1-10 ◽

Cited By ~ 4

Author(s):

Mark Watkins ◽

Hayley Castlehouse ◽

Murray Hannah ◽

David M. Nash

Keyword(s):

Soil Water ◽

Lolium Perenne ◽

Block Design ◽

Dairy Farms ◽

Soil Samples ◽

Nitrogen And Phosphorus ◽

Olsen P ◽

Extractable P ◽

Initial Results ◽

Total P

Untilled dairy pasture has the potential to release more phosphorus to the environment than a regularly ploughed pasture. In this paper we report the initial results of a study comparing the effects of cultivation, phosphorus (P) fertiliser (10, 35, and 100 kg P/ha), and two types of vegetation (ryegrass (Lolium perenne) or ryegrass mixed with clover (Trifolium repens)) in a randomised complete block design. Phosphorus was measured in soil samples taken from depths of 0–20 mm and 0–100 mm. Waters extracted from the 0–20 mm samples were also analysed. In all cases, the P concentrations (Olsen P, Colwell P, Total P, CaCl2extractable P, Dissolved Reactive P, and Total Dissolved P) in the top 20 mm declined with ploughing. Dissolved Reactive P measured in the soil water was 70% less overall in the ploughed plots compared with the unploughed plots, and by 35 weeks after P treatments the decrease in Dissolved Reactive P was 66%. The effects of the fertiliser and pasture treatments were inconclusive. The data suggest that ploughing can lower the risk of P exports from intensive dairy farms in the trial area.

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Depletion, accumulation and availability of soil phosphorus in the Askov long-term field experiment

Soil Research ◽

10.1071/sr19203 ◽

2020 ◽

Vol 58 (2) ◽

pp. 117 ◽

Cited By ~ 1

Author(s):

Musibau O. Azeez ◽

Gitte Holton Rubæk ◽

Ingeborg Frøsig Pedersen ◽

Bent T. Christensen

Keyword(s):

Rock Phosphate ◽

Soil Phosphorus ◽

Available P ◽

Soil P ◽

Olsen P ◽

Extractable P ◽

P Application ◽

Plant Available P ◽

Water Extractable

Soil phosphorus (P) reserves, built up over decades of intensive agriculture, may account for most of the crop P uptake, provided adequate supply of other plant nutrients. Whether crops grown on soils with reduced supply of other nutrients obtain similar use-efficiency of soil P reserves remains unclear. In treatments of the Askov Long-Term Experiment (initiated in 1894 on light sandy loam), we quantified changes in soil total P and in plant-available P (Olsen P, water extractable P and P offtake in wheat grains) when P-depleted soil started receiving P in rock phosphate and when P application to soil with moderate P levels ceased during 1997–2017. Additionally we studied treatments with soil kept unfertilised for >100 years and with soil first being P depleted and then exposed to surplus dressings of P, nitrogen (N) and potassium in cattle manure. For soil kept unfertilised for >100 years, average grain P offtake was 6 kg ha–1 and Olsen P averaged 4.6 mg kg–1, representing the lower asymptotic level of plant-available P. Adding igneous rock phosphate to severely P-depleted soil with no N fertilisation had little effect on Olsen P, water extractable P (Pw), grain yields and P offtake. For soils with moderate levels of available P, withholding P application for 20 years reduced contents of Olsen P by 56% (from 16 to 7 mg P kg–1) and of Pw by 63% (from 4.5 to 1.7 mg P kg–1). However, the level of plant-available P was still above that of unfertilised soil. Application of animal manure to P-depleted soil gradually raised soil P availability, grain yield and P offtake, but it took 20 years to restore levels of plant-available P. Our study suggests symmetry between rates of depletion and accumulation of plant-available P in soil.

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Extractable phosphorus in alkaline soils amended with high rates of organic and inorganic phosphorus

Canadian Journal of Soil Science ◽

10.4141/s03-085 ◽

2004 ◽

Vol 84 (4) ◽

pp. 459-467 ◽

Cited By ~ 14

Author(s):

Md. Abul Kashem ◽

Olalekan Oluwole Akinremi ◽

Geza Joseph Racz

Keyword(s):

Incubation Time ◽

Organic Amendments ◽

Soil Samples ◽

Cattle Manure ◽

Available P ◽

Olsen P ◽

Extractable P ◽

Hog Manure ◽

P Application ◽

Plant Available P

Information on the extractable P in soils treated with different organic amendments and how it changes with time is important to a sound management of manure addition to agriculture soils. This laboratory study investigated the impact of adding municipal biosolids, hog and cattle manures and monoammonium phosphate (MAP) on extractable P in soils. Phosphorus was added at rates of 0, 110, 220, 440 and 880 mg P kg-1 for the Osborne soil (Gleysolic Humic Vertisol), and 0, 123, 307 and 614 mg P kg-1 for the Lakeland soil (Gleyed Rego Black Chernozem) in the form of biosolids, hog manure, cattle manure and MAP. The soils were incubated at field capacity for 1, 4, 16 and 32 wk after which they were extracted using H2O, NH4Cl, NaHCO3 (Olsen P), and the Kelowna and Mehlich-3 extracts. Regardless of extractant and soil, extractable P was small 1 wk after adding biosolids (17-93 mg kg-1 as Olsen P) and large with MAP (59-672 mg kg-1 as Olsen P) while hog and cattle manures were intermediate between biosolids and MAP (20-461 mg kg-1 as Olsen P). In biosolids-amended soils, extractable P increased slightly with increasing incubation time indicating net P mineralization. With MAP, extractable P declined from 672 mg kg-1 after 1 wk to 157 mg kg-1 after 16 wk of incubation at the highest P application rate in the Osborne soil. In the Lakeland soil, the decrease in extractable P with MAP addition was small (from 398 to 332 mg kg-1) and was similar to the changes with cattle manure P with incubation time. Extractable P with cattle manure in the Osborne soil and with hog manure in the Lakeland soil did not change with incubation time. In both soils, extraction efficiency was in the order of H2O < NH4Cl < NaHCO3 < Kelowna < Mehlich-3. Across P application rates, the efficiency of added P as measured by NaHCO3 increased only with biosol ids from 12% after 1 wk to 21% after 32 wk of incubation, while it decreased in the same period from 55 to 44% with hog manure, from 34 to 32% with cattle manure and from 74 to 17% with MAP in the Osborne soil. Soil samples taken 4 wk following addition o f hog and cattle manures should reflect plant-available P, while soil samples taken within the same period following the application of biosolids are likely to underestimate plant-available P. Key words: Extractable phosphorus, organic amendments, soils, single extraction, incubation

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High coffee population density to improve fertility of an oxisol

Pesquisa Agropecuária Brasileira ◽

10.1590/s0100-204x1999000300018 ◽

1999 ◽

Vol 34 (3) ◽

pp. 459-465 ◽

Cited By ~ 17

Author(s):

Marcos Antonio Pavan ◽

Júlio César Dias Chaves ◽

Rubens Siqueira ◽

Armando Androcioli Filho ◽

Arnaldo Colozzi Filho ◽

...

Keyword(s):

Mycorrhizal Fungi ◽

Acid Soils ◽

Arbuscular Mycorrhizal ◽

Residue Management ◽

Plant Residue ◽

Coffee Tree ◽

Tree Population ◽

Exchangeable Ca ◽

Exchangeable Al ◽

Extractable P

The objective of this work was to evaluate the effect of coffee (Coffea arabica L.) population densities on the chemical and microbiological properties of an Oxisol. The work was carried out on soil samples of 0-20 cm depth originated from an experimental site which had been used for coffee tree spacing studies during 15 years, in Paraná State, Brazil. Eight coffee tree populations were evaluated: 7143, 3571, 2381, 1786, 1429, 1190, 1020, and 893 trees/ha. Increasing plant population increased soil pH, exchangeable Ca, Mg, K, extractable P, organic carbon, moisture content and coffee root colonization by vesicular arbuscular mycorrhizal fungi, and decreased exchangeable Al and microbial biomass. Such results were attributed to better erosion control, improved plant residue management and nutrient cycling, and decreased leaching losses. Increasing coffee tree population per unit of area has shown to be an important reclamation recuperation strategy for improving fertility of the acid soils in Paraná, Brazil.

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