A - Papers appearing in refereed journals
Hawkins, J. M. B., Vermeiren, C., Blackwell, M. S. A., Darch, T., Granger, S. J., Dunham, S. J., Hernandez, J. M. B., Smolders, E. and McGrath, S. P. 2022. The effect of soil organic matter on long-term availability of phosphorus in soil: evaluation in a biological P mining experiment. Geoderma. 423, p. 115965. https://doi.org/10.1016/j.geoderma.2022.115965
Authors | Hawkins, J. M. B., Vermeiren, C., Blackwell, M. S. A., Darch, T., Granger, S. J., Dunham, S. J., Hernandez, J. M. B., Smolders, E. and McGrath, S. P. |
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Abstract | The plant uptake of legacy phosphorus (P) from over-fertilised agricultural soils could offer a solution to decrease dependency on finite mineral P resources. This study evaluated the long-term availability of legacy P in soils with an accelerated biological mining assay, thereby testing to what extent this availability is affected by soil organic carbon (SOC). A 15-months long pot trial was set-up, in which 25 soils with 1.2-24% SOC were mined for P by continuous cropping and harvesting of ryegrass (Lolium Perenne) in a plant growth cabinet. The cumulative uptake of P was, on average, 19% of the P associated with poorly crystalline iron (Fe) and aluminium (Al) (oxy)hydroxides (oxalate-extractable P; Pox), and half of this uptake occurred fast enough to maintain crop production at an adequate level of > 90% of its potential. This P available for adequate uptake (PUA) strikingly matched with the isotopically exchangeable P or “E value” of a soil (median PUA/E24h = 0.81), whereas it was markedly underestimated by Olsen P (median PUA/POlsen = 1.51). The fractions of plant-available Pox increased at increasing ratios of P and SOC to Feox and Alox, showing that enhanced SOC contents reduce ageing of P by preventing its diffusion into micropores. That effect of SOC on P availability was more pronounced in soils with a low initial P saturation status. The comparison of the results from biological mining with available soil P pools determined in a (sterile) P desorption experiment could not confirm a significant contribution of organic P to plant P supply. Our findings suggest that legacy P in well-fertilised agricultural soils could act as a sufficient P source for plants for 12-175 years, and that this long-term availability is positively affected by SOC as long as the soil is not too highly saturated with P. |
Keywords | Accelerated biological mining; Ageing; Availability; Long-term; Phosphorus; Soil organic carbon |
Year of Publication | 2022 |
Journal | Geoderma |
Journal citation | 423, p. 115965 |
Digital Object Identifier (DOI) | https://doi.org/10.1016/j.geoderma.2022.115965 |
Open access | Published as green open access |
Funder | Biotechnology and Biological Sciences Research Council |
Funder project or code | S2N - Soil to Nutrition - Work package 1 (WP1) - Optimising nutrient flows and pools in the soil-plant-biota system |
BBS/EC/00005197 | |
The Rothamsted Long Term Experiments [2017-2022] | |
Accepted author manuscript | Copyright license CC BY |
Supplemental file | Copyright license CC BY |
Output status | Published |
Publication dates | |
Online | 03 Jun 2022 |
Publication process dates | |
Accepted | 26 May 2022 |
Publisher | Elsevier Science Bv |
ISSN | 0016-7061 |
Permalink - https://repository.rothamsted.ac.uk/item/986x3/the-effect-of-soil-organic-matter-on-long-term-availability-of-phosphorus-in-soil-evaluation-in-a-biological-p-mining-experiment
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