Iodine bioavailability in acidic soils of Northern Ireland

Bowley, H.E.; Young, S.D.; Ander, E.L.; Crout, N.M.J.; Watts, M.J.; Bailey, E.H.

Abstract

Iodine is an essential trace element for humans and grazing animals and is often deficient. Our aim was to investigate the role of soil properties in retaining and ‘fixing' iodine in soils and thereby controlling its phyto-availability to grass. Soils were spiked with labelled 129IO3− and rye grass (Lolium perenne L.) was grown to measure iodine uptake by grass as a function of yield, soil properties and continuous 127I inputs from irrigation water. Iodine-129 added at the start of the uptake trial was rapidly fixed (t1/2 c. 40 h) into non-labile humus-bound forms in soil. The 129I/127I isotopic ratio in grass, compared to the ratio in soil, declined over time confirming progressive 129I fixation into the soil solid phase. The rate of fixation was controlled by soil properties. A model describing iodine dynamics and uptake accounted for c. 75% of the variation in iodine concentration in grass. For most of the soils studied, the main source of iodine in herbage probably arises from the transient availability of periodic rainfall inputs rather than from soil sources. This is expected to improve biofortification strategies.

Citation

Bowley, H., Young, S., Ander, E., Crout, N., Watts, M., & Bailey, E. (2019). Iodine bioavailability in acidic soils of Northern Ireland. Geoderma, 348, 97-106. https://doi.org/10.1016/j.geoderma.2019.04.020

• Journal Article Type: Article
• Acceptance Date: Apr 16, 2019
• Online Publication Date: Apr 25, 2019
• Publication Date: Aug 15, 2019
• Deposit Date: Apr 30, 2019
• Publicly Available Date: Apr 26, 2020
• Journal: Geoderma
• Print ISSN: 0016-7061
• Electronic ISSN: 1872-6259
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 348
• Pages: 97-106
• DOI: https://doi.org/10.1016/j.geoderma.2019.04.020
• Keywords: Iodine; Rainfall input; Irrigation input ; Soil; Plant uptake; Speciation
• Public URL: https://nottingham-repository.worktribe.com/output/1883140
• Publisher URL: https://www.sciencedirect.com/science/article/pii/S001670611930121
• Additional Information: This article is maintained by: Elsevier; Article Title: Iodine bioavailability in acidic soils of Northern Ireland; Journal Title: Geoderma; CrossRef DOI link to publisher maintained version: https://doi.org/10.1016/j.geoderma.2019.04.020; Content Type: article; Copyright: © 2019 Elsevier B.V. All rights reserved.
• Contract Date: Jun 25, 2019