The University of Southampton
University of Southampton Institutional Repository
Warning ePrints Soton is experiencing an issue with some file downloads not being available. We are working hard to fix this. Please bear with us.

Image based modeling of nutrient movement in and around the rhizosphere

Image based modeling of nutrient movement in and around the rhizosphere
Image based modeling of nutrient movement in and around the rhizosphere
In this study, we developed a spatially explicit model for nutrient uptake by root hairs based on X-ray computed tomography images of the rhizosphere soil structure. This work extends our previous work to larger domains and hence is valid for longer times. Unlike the model used previously, which considered only a small region of soil about the root, we considered an effectively infinite volume of bulk soil about the rhizosphere. We asked the question: At what distance away from root surfaces do the specific structural features of root-hair and soil aggregate morphology not matter because average properties start dominating the nutrient transport? The resulting model was used to capture bulk and rhizosphere soil properties by considering representative volumes of soil far from the root and adjacent to the root, respectively. By increasing the size of the volumes that we considered, the diffusive impedance of the bulk soil and root uptake were seen to converge. We did this for two different values of water content. We found that the size of region for which the nutrient uptake properties converged to a fixed value was dependent on the water saturation. In the fully saturated case, the region of soil we needed to consider was only of radius 1.1mm for poorly soil-mobile species such as phosphate. However, in the case of a partially saturated medium (relative saturation 0.3), we found that a radius of 1.4mm was necessary. This suggests that, in addition to the geometrical properties of the rhizosphere, there is an additional effect of soil moisture properties, which extends further from the root and may relate to other chemical changes in the rhizosphere. The latter were not explicitly included in our model.
phosphate, plant–soil interaction, rhizosphere, structural imaging, x-ray CT
0022-0957
1-12
Daly, K.R.
e28b1acf-cdde-4b52-8d83-cf314d7c3466
Keyes, S.D.
df85cb02-c26a-4aed-9000-8388bfa74cd1
Masum, S.
8cf47074-ccd4-48ff-b3f4-5facd3a450e6
Roose, T.
3581ab5b-71e1-4897-8d88-59f13f3bccfe
Daly, K.R.
e28b1acf-cdde-4b52-8d83-cf314d7c3466
Keyes, S.D.
df85cb02-c26a-4aed-9000-8388bfa74cd1
Masum, S.
8cf47074-ccd4-48ff-b3f4-5facd3a450e6
Roose, T.
3581ab5b-71e1-4897-8d88-59f13f3bccfe

Daly, K.R., Keyes, S.D., Masum, S. and Roose, T. (2016) Image based modeling of nutrient movement in and around the rhizosphere. Journal of Experimental Botany, 1-12. (doi:10.1093/jxb/erv544).

Record type: Article

Abstract

In this study, we developed a spatially explicit model for nutrient uptake by root hairs based on X-ray computed tomography images of the rhizosphere soil structure. This work extends our previous work to larger domains and hence is valid for longer times. Unlike the model used previously, which considered only a small region of soil about the root, we considered an effectively infinite volume of bulk soil about the rhizosphere. We asked the question: At what distance away from root surfaces do the specific structural features of root-hair and soil aggregate morphology not matter because average properties start dominating the nutrient transport? The resulting model was used to capture bulk and rhizosphere soil properties by considering representative volumes of soil far from the root and adjacent to the root, respectively. By increasing the size of the volumes that we considered, the diffusive impedance of the bulk soil and root uptake were seen to converge. We did this for two different values of water content. We found that the size of region for which the nutrient uptake properties converged to a fixed value was dependent on the water saturation. In the fully saturated case, the region of soil we needed to consider was only of radius 1.1mm for poorly soil-mobile species such as phosphate. However, in the case of a partially saturated medium (relative saturation 0.3), we found that a radius of 1.4mm was necessary. This suggests that, in addition to the geometrical properties of the rhizosphere, there is an additional effect of soil moisture properties, which extends further from the root and may relate to other chemical changes in the rhizosphere. The latter were not explicitly included in our model.

Text
150902_Figures.docx - Other
Download (3MB)
Text
151127_Corrected.docx - Accepted Manuscript
Available under License Other.
Download (188kB)
Text
150922_SupplementaryFigures.docx - Other
Download (258kB)

More information

Accepted/In Press date: 2 December 2015
e-pub ahead of print date: 5 January 2016
Keywords: phosphate, plant–soil interaction, rhizosphere, structural imaging, x-ray CT
Organisations: Faculty of Engineering and the Environment

Identifiers

Local EPrints ID: 384502
URI: http://eprints.soton.ac.uk/id/eprint/384502
ISSN: 0022-0957
PURE UUID: a3d13ed0-a8f5-402d-a06a-f1dd7d64df23
ORCID for T. Roose: ORCID iD orcid.org/0000-0001-8710-1063

Catalogue record

Date deposited: 07 Jan 2016 15:34
Last modified: 21 Nov 2021 03:01

Export record

Altmetrics

Contributors

Author: K.R. Daly
Author: S.D. Keyes
Author: S. Masum
Author: T. Roose ORCID iD

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×