Evaluation of phosphorus mobility in soil using different extraction methods

Soil samples (from Czech and German long-term field experiments) were used to estimate different soil phosphorus (P) fractions. More than 200 topsoil (0–30 cm) samples from different fertilizing treatments were taken. These were analyzed for P in soil solution (PCaCl2) [0.01M CaCl2 extract], exchangeable sorbed P (Pex) [anion exchange (AE) membranes] and bioavailable P [Doppel-Lactat and Mehlich 3 (PDL and PM3)]. Other fractions analyzed were total inorganic (Pin), total (PM-tot) and organic (Porg) P [fractionation after Marks], P sorbed on Fe and Al (PFeAl) [fractionation after Schwertmann] and residual P (Par) [aqua regia extract]. Comparison of medians appeared to be better for evaluating extraction abilities. Phosphorus fractions were in the following order: (Par = 100%); PCaCl2 (0.2%) < Pex (9%) < PDL (10%) < PM3 (16%) < Pin (24%) < Porg (37%) < PFeAl (55%) < PM-tot (59%). Low amounts of Pin, Porg and PM-tot did not verify the applicability of the Marks’ fractionation for the set of studied soils. Close correlations at P ≤ 0.001 were found for all methods for estimating the fractions of bioavailable phosphates (PCaCl2, Pex, PDL and PM3). Statistically significant relations were observed between Pin with Par, PM-tot and PFeAl.

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Implications of long-term superphosphate applications on the accumulation and plant availability of soil phosphorus under irrigated pastures

Proceedings of the New Zealand Grassland Association ◽

10.33584/jnzg.1990.52.1945 ◽

1990 ◽

pp. 191-193

Author(s):

L.M. Condron ◽

K.M. Goh

Keyword(s):

Dynamic Balance ◽

Soil Phosphorus ◽

Organic P ◽

P Fractionation ◽

Inorganic P ◽

Soil P ◽

Grazed Pasture ◽

P Addition ◽

Apparent Stability

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. Keywords grazed pasture, irrigation, fertiliser P, soil inorganic P, soil organic P, soil P fractionation

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Soil phosphorus and potassium availability in long-term field experiments with organic and mineral fertilization

Plant Soil and Environment ◽

10.17221/534/2016-pse ◽

2016 ◽

Vol 62 (No. 12) ◽

pp. 558-565 ◽

Cited By ~ 4

Author(s):

M. Káš ◽

G. Mühlbachová ◽

H. Kusá ◽

M. Pechová

Keyword(s):

Field Experiments ◽

Soil Phosphorus ◽

Mineral Fertilization ◽

Phosphorus And Potassium ◽

Term Field

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Comparison of fractionation methods for soil phosphorus with soils subjected to various long-term fertilization regimes on a calcareous soil

10.7717/peerj-ichem.3 ◽

2021 ◽

Vol 3 ◽

pp. e3

Author(s):

Xin Jin ◽

Changlu Hu ◽

Asif Khan ◽

Shulan Zhang ◽

Xueyun Yang ◽

...

Keyword(s):

Calcareous Soil ◽

Soil Phosphorus ◽

Calcareous Soils ◽

P Uptake ◽

Organic P ◽

P Fractions ◽

P Fractionation ◽

Inorganic P ◽

Soil P

Background Diverse phosphorus (P) fractionation procedures presented varying soil P fractions, which directly affected P contents and forms, and their biological availability. Purpose To facilitate the selection of phosphorus (P) fractionation techniques, we compared two procedures based on a long-term experiment on a calcareous soil. Methods The soils containing a gradient P levels were sampled from seven treatments predictor under various long-term fertilizations. The P fractions were then separated independently with both fractionation procedures modified by Tiessen-Moir and Jiang-Gu. Results The results showed that the labile P in Jiang-Gu is significantly lower than that in Tiessen-Moir. The iron and aluminium-bounded P were greater in Jiang-Gu by a maximum of 46 mg kg−1 than Tiessen-Moir. Jiang-Gu fractionation gave similar Ca bounded P to that Tiessen-Moir did at low P level but greater contents at high P level. The two methods extracted much comparable total inorganic P. However, Tiessen-Moir method accounted less total organic P than ignition or Jiang-Gu method (the organic P (Po) estimated by subtract the total inorganic P (Pi) in Jiang-Gu fractionation from the total). P uptake by winter wheat was significantly and positively correlated with all phosphorus fractions in Jiang-Gu; Resin-P, NaHCO3-Pi, D. HCl-P, C. HCl-Pi, NaOH-Po, total-Po in Tiessen-Moir; P fraction categories of Ca-P, Fe & Al-P and total-Pi in both fractionations. Path coefficients indicated that Ca2-P in Jiang-Gu, NaHCO3-Pi and D. HCl-P in Tiessen-Moir had the higher and more significant direct contributions to P uptake among P fractions measured. Conclusions Our results suggested that Jiang-Gu procedure is a better predictor in soil P fractionation in calcareous soils, although it gives no results on organic P fractions.

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