{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,19]],"date-time":"2026-05-19T14:18:44Z","timestamp":1779200324382,"version":"3.51.4"},"reference-count":44,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2015,10,5]],"date-time":"2015-10-05T00:00:00Z","timestamp":1444003200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003593","name":"Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100003593","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002322","name":"Coordena\u00e7\u00e3o de Aperfei\u00e7oamento de Pessoal de N\u00edvel Superior","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100002322","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004901","name":"Funda\u00e7\u00e3o de Amparo \u00e0 Pesquisa do Estado de Minas Gerais","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100004901","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The scarcity of drinking water affects various regions of the planet. Although climate change is responsible for the water availability, humanity plays an important role  in preserving this precious natural resource. In case of negligence, the likely trend is to increase the demand and the depletion of water resources due to the increasing world population. This paper addresses the development, design and construction of a low cost system for measuring soil volumetric water content (\u03b8), electrical conductivity (\u03c3) and temperature (T), in order to optimize the use of water, energy and fertilizer in food production. Different from the existing measurement instruments commonly deployed in these applications, the proposed system uses an auto-balancing bridge circuit as measurement method. The proposed models to estimate \u03b8 and \u03c3 and correct them in function of T are compared to the ones reported in literature. The final prototype corresponds to a simple circuit connected to a pair of electrode probes, and presents high accuracy, high signal to noise ratio, fast response, and immunity to stray capacitance. The instrument calibration is based on salt solutions with known dielectric constant and electrical conductivity as reference. Experiments measuring clay and sandy soils demonstrate the satisfactory performance of the instrument.<\/jats:p>","DOI":"10.3390\/s151025546","type":"journal-article","created":{"date-parts":[[2015,10,5]],"date-time":"2015-10-05T10:26:41Z","timestamp":1444040801000},"page":"25546-25563","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["A Novel Low-Cost Instrumentation System for Measuring the Water Content and Apparent Electrical Conductivity of Soils"],"prefix":"10.3390","volume":"15","author":[{"given":"Alan","family":"R\u00eago Segundo","sequence":"first","affiliation":[{"name":"Department of Control and Automation Engineering and Fundamental Techniques, School of Mines, Federal University of Ouro Preto (UFOP)\u2014campus Morro do Cruzeiro, sn,  35400-000 Ouro Preto, MG, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jos\u00e9","family":"Martins","sequence":"additional","affiliation":[{"name":"Department of Agricultural Engineering, Federal University of Vi\u00e7osa (UFV)\u2014Avenida P.H. Rolfs, sn, 36570-900 Vi\u00e7osa, MG, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Paulo","family":"Monteiro","sequence":"additional","affiliation":[{"name":"Department of Control and Automation Engineering and Fundamental Techniques, School of Mines, Federal University of Ouro Preto (UFOP)\u2014campus Morro do Cruzeiro, sn,  35400-000 Ouro Preto, MG, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rubens","family":"De Oliveira","sequence":"additional","affiliation":[{"name":"Department of Agricultural Engineering, Federal University of Vi\u00e7osa (UFV)\u2014Avenida P.H. Rolfs, sn, 36570-900 Vi\u00e7osa, MG, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gustavo","family":"Freitas","sequence":"additional","affiliation":[{"name":"Vale Institute of Technology (ITV)\u2014Avenida Juscelino Kubitschek, 31, Bauxita,  35400-000 Ouro Preto, MG, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2015,10,5]]},"reference":[{"key":"ref_1","unstructured":"United Nations Educational, Scientific and Cultural Organization Launch Water Cooperation 2013. Available online: http:\/\/www.unesco.org\/new\/en\/natural-sciences\/environment\/water\/water-cooperation-2013\/launch-water-cooperation-2013\/."},{"key":"ref_2","first-page":"455","article-title":"Application of soil electrical conductivity to precision agriculture: Theory, principles, and guidelines","volume":"95","author":"Corwin","year":"2003","journal-title":"Agron. 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