{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,15]],"date-time":"2026-05-15T17:05:07Z","timestamp":1778864707540,"version":"3.51.4"},"reference-count":48,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2024,9,29]],"date-time":"2024-09-29T00:00:00Z","timestamp":1727568000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Key Research and Development Program of China","award":["2022YFC3705001"],"award-info":[{"award-number":["2022YFC3705001"]}]},{"name":"National Key Research and Development Program of China","award":["2023-002"],"award-info":[{"award-number":["2023-002"]}]},{"name":"National Key Research and Development Program of China","award":["DD20221728"],"award-info":[{"award-number":["DD20221728"]}]},{"name":"Program of MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing)","award":["2022YFC3705001"],"award-info":[{"award-number":["2022YFC3705001"]}]},{"name":"Program of MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing)","award":["2023-002"],"award-info":[{"award-number":["2023-002"]}]},{"name":"Program of MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing)","award":["DD20221728"],"award-info":[{"award-number":["DD20221728"]}]},{"name":"the China Geological Survey Program","award":["2022YFC3705001"],"award-info":[{"award-number":["2022YFC3705001"]}]},{"name":"the China Geological Survey Program","award":["2023-002"],"award-info":[{"award-number":["2023-002"]}]},{"name":"the China Geological Survey Program","award":["DD20221728"],"award-info":[{"award-number":["DD20221728"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Soil dielectric sensors have been widely used to obtain real-time soil moisture data, which are important for water resource management. However, soluble salts in the soil significantly affect the accuracy of these sensor measurements. Therefore, it is crucial to select suitable soil dielectric sensors for soil moisture measurements at different salinity levels. Eight mainstream sensors (EC-5, 5TE, Teros12, Hydra-probe II, TDR315L, TDR315H, TDR305H, and CS655) were selected and tested at four different soil salinity levels (EC1:5 = 3.0, 1.5, 1.0, and 0.75 dS\u00b7m\u22121). The measured values using the factory calibration formulas were compared at six soil moisture levels. The results showed that the measured soil moisture values from various sensors exhibited varying degrees of overestimation, which increased with increasing salinity. Only EC-5 did not exhibit distortion at high-salinity levels, with the measured values showing a good linear trend compared to the standard values. Mutational distortion of the measured apparent dielectric permittivity occurred in TDR315L, TDR315H, Hydra-probe II, and 5TE at EC1:5 = 3.0 dS\u00b7m\u22121. Insensitive distortion of the measured apparent dielectric permittivity occurred in Teros12 and TDR305H at EC1:5 = 3.0 dS\u00b7m\u22121 as well as in Teros12, TDR305H, 5TE and Hydra-probe II at EC1:5 = 1.5 dS\u00b7m\u22121. All tested sensors performed reasonably well at EC1:5 \u2264 1.0 dS\u00b7m\u22121. Seven sensors (excluding CS655) were calibrated within the distortion threshold. The soil moisture accuracy using the calibrated formulas could reach \u00b10.02 cm3\u00b7cm\u22123. At EC1:5 \u2264 1.0 dS\u00b7m\u22121, most sensors in this study could be applied with the factory calibration formulas. TDR series, EC-5, 5TE and Teros12 were recommended after calibration for EC1:5 &gt; 1.0 dS\u00b7m\u22121. For extremely high soil salinity levels, the TDR series and EC-5 may be the best choices.<\/jats:p>","DOI":"10.3390\/s24196323","type":"journal-article","created":{"date-parts":[[2024,9,30]],"date-time":"2024-09-30T07:19:37Z","timestamp":1727680777000},"page":"6323","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":21,"title":["Performance of Soil Moisture Sensors at Different Salinity Levels: Comparative Analysis and Calibration"],"prefix":"10.3390","volume":"24","author":[{"given":"Qiuju","family":"Qi","sequence":"first","affiliation":[{"name":"Nanjing Center, China Geological Survey, Nanjing 210016, China"},{"name":"Key Laboratory of Watershed Eco-Geological Processes, Ministry of Natural Resources, Nanjing 210016, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hai","family":"Yang","sequence":"additional","affiliation":[{"name":"Nanjing Center, China Geological Survey, Nanjing 210016, China"},{"name":"Key Laboratory of Watershed Eco-Geological Processes, Ministry of Natural Resources, Nanjing 210016, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Quanping","family":"Zhou","sequence":"additional","affiliation":[{"name":"Nanjing Center, China Geological Survey, Nanjing 210016, China"},{"name":"Key Laboratory of Watershed Eco-Geological Processes, Ministry of Natural Resources, Nanjing 210016, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0199-9779","authenticated-orcid":false,"given":"Xiaole","family":"Han","sequence":"additional","affiliation":[{"name":"College of Hydrology and Water Resources, Hohai University, Nanjing 210098, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhengyang","family":"Jia","sequence":"additional","affiliation":[{"name":"Nanjing Center, China Geological Survey, Nanjing 210016, China"},{"name":"Key Laboratory of Watershed Eco-Geological Processes, Ministry of Natural Resources, Nanjing 210016, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yuehua","family":"Jiang","sequence":"additional","affiliation":[{"name":"Nanjing Center, China Geological Survey, Nanjing 210016, China"},{"name":"Key Laboratory of Watershed Eco-Geological Processes, Ministry of Natural Resources, Nanjing 210016, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1787-5447","authenticated-orcid":false,"given":"Zi","family":"Chen","sequence":"additional","affiliation":[{"name":"Nanjing Center, China Geological Survey, Nanjing 210016, China"},{"name":"MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing), Beijing 100083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lili","family":"Hou","sequence":"additional","affiliation":[{"name":"Nanjing Center, China Geological Survey, Nanjing 210016, China"},{"name":"Key Laboratory of Watershed Eco-Geological Processes, Ministry of Natural Resources, Nanjing 210016, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shijia","family":"Mei","sequence":"additional","affiliation":[{"name":"Nanjing Center, China Geological Survey, Nanjing 210016, China"},{"name":"Key Laboratory of Watershed Eco-Geological Processes, Ministry of Natural Resources, Nanjing 210016, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,9,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"358","DOI":"10.2136\/vzj2007.0143","article-title":"Soil moisture measurement for ecological and hydrological watershed-scale observatories: A review","volume":"7","author":"Robinson","year":"2008","journal-title":"Vadose Zone J."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"265","DOI":"10.13031\/trans.13428","article-title":"Evaluation and calibration of soil moisture sensors in undisturbed soils","volume":"63","author":"Feng","year":"2020","journal-title":"Trans. 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