Estimating Soil Solution Nitrate Concentration from Dielectric Spectra Using Partial Least Squares Analysis

dc.contributor.author Birrell, Stuart
dc.contributor.author Chighladze, Giorgi
dc.contributor.author Kaleita, Amy
dc.contributor.author Birrell, Stuart
dc.contributor.author Kaleita, Amy
dc.contributor.author Logsdon, Sally
dc.contributor.department Agricultural and Biosystems Engineering
dc.date 2018-02-13T07:06:34.000
dc.date.accessioned 2020-06-29T22:38:40Z
dc.date.available 2020-06-29T22:38:40Z
dc.date.embargo 2013-03-11
dc.date.issued 2012-09-12
dc.description.abstract <p>Fast and reliable methods for in situ monitoring of soil NO<sub>3</sub>–N concentration could help guide efforts to reduce NO<sub>3</sub>–N losses to ground and surface waters from agricultural systems. While several studies have been done to indirectly estimate NO<sub>3</sub>–N concentrations from time domain spectra, no research has been conducted using a frequency domain technique. Hence, the goal of this laboratory study was to estimate NO<sub>3</sub>–N concentrations from frequency-response data obtained in a frequency range of 5 Hz to 13 MHz. Dielectric spectra of soil samples wetted to five different volumetric water contents (VWC) with 24 solutions containing different concentrations of KNO<sub>3</sub> and KCl were analyzed using a partial least squares (PLS) regression method. Global models could not estimate NO<sub>3</sub>–N concentrations with sufficient accuracy. Models based on the imaginary part of the permittivity were better than those based on the real part. The PLS model estimates were improved when low VWC data and high Cl<sup>−</sup> concentration were eliminated, reducing the RMSE for NO<sub>3</sub>–N from 57 to 28 mg L<sup>−1</sup>. The best results were obtained when the PLS models were constructed at fixed VWC levels using the data without high Cl<sup>−</sup> concentration. The performance of these models improved with increasing VWC level, reaching the lowest RMSE of 18 mg L<sup>−1</sup> at VWC of 0.30 m<sup>3</sup> m<sup>−3</sup>.</p>
dc.description.comments <p>This article is from <em>Soil Science Society of America Journal </em>76, no. 5 (2012): 1536–1547, doi:<a href="http://dx.doi.org/10.2136/sssaj2011.0391" target="_blank">10.2136/sssaj2011.0391</a>.</p>
dc.format.mimetype application/pdf
dc.identifier archive/lib.dr.iastate.edu/abe_eng_pubs/296/
dc.identifier.articleid 1573
dc.identifier.contextkey 3885762
dc.identifier.s3bucket isulib-bepress-aws-west
dc.identifier.submissionpath abe_eng_pubs/296
dc.identifier.uri https://dr.lib.iastate.edu/handle/20.500.12876/1046
dc.language.iso en
dc.source.bitstream archive/lib.dr.iastate.edu/abe_eng_pubs/296/2012_ChighladzeG_EstimatingSoilSolution.pdf|||Fri Jan 14 23:15:16 UTC 2022
dc.source.uri 10.2136/sssaj2011.0391
dc.subject.disciplines Agriculture
dc.subject.disciplines Bioresource and Agricultural Engineering
dc.subject.disciplines Life Sciences
dc.subject.disciplines Soil Science
dc.title Estimating Soil Solution Nitrate Concentration from Dielectric Spectra Using Partial Least Squares Analysis
dc.type article
dc.type.genre article
dspace.entity.type Publication
relation.isAuthorOfPublication 1fd6ff71-dbea-4ada-9267-f9ff2ce1caba
relation.isAuthorOfPublication 8a405b08-e1c8-4a10-b458-2f5a82fcf148
relation.isOrgUnitOfPublication 8eb24241-0d92-4baf-ae75-08f716d30801
File
Original bundle
Now showing 1 - 1 of 1
Name:
2012_ChighladzeG_EstimatingSoilSolution.pdf
Size:
1.26 MB
Format:
Adobe Portable Document Format
Description:
Collections