{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,25]],"date-time":"2026-01-25T08:32:42Z","timestamp":1769329962674,"version":"3.49.0"},"reference-count":35,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2017,6,20]],"date-time":"2017-06-20T00:00:00Z","timestamp":1497916800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This work deals with the fabrication, prototyping, and experimental validation of a fiber optic thermo-hygrometer-based soil moisture sensor, useful for rainfall-induced landslide prevention applications. In particular, we recently proposed a new generation of fiber Bragg grating (FBGs)-based soil moisture sensors for irrigation purposes. This device was realized by integrating, inside a customized aluminum protection package, a FBG thermo-hygrometer with a polymer micro-porous membrane. Here, we first verify the limitations, in terms of the volumetric water content (VWC) measuring range, of this first version of the soil moisture sensor for its exploitation in landslide prevention applications. Successively, we present the development, prototyping, and experimental validation of a novel, optimized version of a soil VWC sensor, still based on a FBG thermo-hygrometer, but able to reliably monitor, continuously and in real-time, VWC values up to 37% when buried in the soil.<\/jats:p>","DOI":"10.3390\/s17061451","type":"journal-article","created":{"date-parts":[[2017,6,20]],"date-time":"2017-06-20T10:15:38Z","timestamp":1497953738000},"page":"1451","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":28,"title":["Fiber Optic Thermo-Hygrometers for Soil Moisture Monitoring"],"prefix":"10.3390","volume":"17","author":[{"given":"Marco","family":"Leone","sequence":"first","affiliation":[{"name":"Optoelectronic Division, Department of Engineering, University of Sannio, 82100 Benevento, Italy"}]},{"given":"Sofia","family":"Principe","sequence":"additional","affiliation":[{"name":"Optoelectronic Division, Department of Engineering, University of Sannio, 82100 Benevento, Italy"}]},{"given":"Marco","family":"Consales","sequence":"additional","affiliation":[{"name":"Optoelectronic Division, Department of Engineering, University of Sannio, 82100 Benevento, Italy"}]},{"given":"Roberto","family":"Parente","sequence":"additional","affiliation":[{"name":"Optoelectronic Division, Department of Engineering, University of Sannio, 82100 Benevento, Italy"}]},{"given":"Armando","family":"Laudati","sequence":"additional","affiliation":[{"name":"Optosmart s.r.l., 80055 Portici (NA), Italy"}]},{"given":"Stefano","family":"Caliro","sequence":"additional","affiliation":[{"name":"Istituto Nazionale di Geofisica e Vulcanologia\u2014INGV, Osservatorio Vesuviano, 80124 Napoli, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8522-6695","authenticated-orcid":false,"given":"Antonello","family":"Cutolo","sequence":"additional","affiliation":[{"name":"Optoelectronic Division, Department of Engineering, University of Sannio, 82100 Benevento, Italy"}]},{"given":"Andrea","family":"Cusano","sequence":"additional","affiliation":[{"name":"Optoelectronic Division, Department of Engineering, University of Sannio, 82100 Benevento, Italy"}]}],"member":"1968","published-online":{"date-parts":[[2017,6,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2715","DOI":"10.5194\/nhess-15-2715-2015","article-title":"Determination of rainfall thresholds for shallow landslides by a probabilistic and empirical method","volume":"15","author":"Huang","year":"2015","journal-title":"Nat. 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