{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,3]],"date-time":"2026-04-03T00:52:56Z","timestamp":1775177576044,"version":"3.50.1"},"reference-count":48,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2018,4,6]],"date-time":"2018-04-06T00:00:00Z","timestamp":1522972800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003151","name":"Fonds de recherche du Qu\u00e9bec \u2013 Nature et technologies","doi-asserted-by":"publisher","award":["2015-NC-180817"],"award-info":[{"award-number":["2015-NC-180817"]}],"id":[{"id":"10.13039\/501100003151","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000038","name":"Natural Sciences and Engineering Research Council of Canada","doi-asserted-by":"publisher","award":["RGPIN-2014-04100"],"award-info":[{"award-number":["RGPIN-2014-04100"]}],"id":[{"id":"10.13039\/501100000038","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Several studies have demonstrated the potential of actively heated fiber optics (AHFO) to measure soil water content (SWC) at high spatial and temporal resolutions. This study tested the feasibility of the AHFO technique to measure soil water in the surface soil of a crop grown field over a growing season using an in-situ calibration approach. Heat pulses of five minutes duration were applied at a rate of 7.28 W m\u22121 along eighteen fiber optic cable transects installed at three depths (0.05, 0.10 and 0.20 m) at six-hour intervals. Cumulative temperature increase (Tcum) during heat pulses was calculated at locations along the cable. While predicting commercial sensor measurements, the AHFO showed root mean square errors (RMSE) of 2.8, 3.7 and 3.7% for 0.05, 0.10 and 0.20 m depths, respectively. Further, the coefficients of determination (R2) for depth specific relationships were 0.87 (0.05 m depth), 0.46 (0.10 m depth), 0.86 (0.20 m depth) and 0.66 (all depths combined). This study showed a great potential of the AHFO technique to measure soil water at high spatial resolutions (&lt;1 m) and to monitor soil water dynamics of surface soil in a crop grown field over a cropping season with a reasonable compromise between accuracy and practicality.<\/jats:p>","DOI":"10.3390\/s18041116","type":"journal-article","created":{"date-parts":[[2018,4,10]],"date-time":"2018-04-10T13:06:08Z","timestamp":1523365568000},"page":"1116","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["Soil Water Measurement Using Actively Heated Fiber Optics at Field Scale"],"prefix":"10.3390","volume":"18","author":[{"given":"Duminda","family":"Vidana Gamage","sequence":"first","affiliation":[{"name":"Department of Natural Resource Sciences, McGill University, 21111 Lakeshore Road, Ste-Anne-de-Bellevue, QC H9X 3V9, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0801-3546","authenticated-orcid":false,"given":"Asim","family":"Biswas","sequence":"additional","affiliation":[{"name":"School of Environmental Sciences, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ian","family":"Strachan","sequence":"additional","affiliation":[{"name":"Department of Natural Resource Sciences, McGill University, 21111 Lakeshore Road, Ste-Anne-de-Bellevue, QC H9X 3V9, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7279-3597","authenticated-orcid":false,"given":"Viacheslav","family":"Adamchuk","sequence":"additional","affiliation":[{"name":"Department of Bioresource Engineering, McGill University, 21111 Lakeshore Road, Ste Anne-de-Bellevue, QC H9X 3V9, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,4,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"206","DOI":"10.1016\/j.jhydrol.2016.03.007","article-title":"Initial soil moisture effects on flash flood generation\u2014A comparison between basins of contrasting hydro-climatic conditions","volume":"541","author":"Grillakis","year":"2016","journal-title":"J. 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