{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,18]],"date-time":"2026-01-18T11:40:49Z","timestamp":1768736449261,"version":"3.49.0"},"reference-count":37,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2022,11,23]],"date-time":"2022-11-23T00:00:00Z","timestamp":1669161600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"UK Biotechnology and Biological Sciences Research Council under the SARIC program","award":["BB\/P004539\/1"],"award-info":[{"award-number":["BB\/P004539\/1"]}]},{"name":"UK Biotechnology and Biological Sciences Research Council under the SARIC program","award":["81133"],"award-info":[{"award-number":["81133"]}]},{"name":"Solar Photovoltaic Academic Research Consortium II (SPARC II) project","award":["BB\/P004539\/1"],"award-info":[{"award-number":["BB\/P004539\/1"]}]},{"name":"Solar Photovoltaic Academic Research Consortium II (SPARC II) project","award":["81133"],"award-info":[{"award-number":["81133"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Crop productivity is highly dependent on the availability of soluble nitrogen (N), e.g. nitrate, in soil. When N levels are low, fertilisers are applied to replenish the soil\u2019s reserves. Typically the timing of these applications is based on paper-based guidance and sensor-based measurements of canopy greenness, which provides an indirect measure of soil N status. However this approach often means that N fertiliser is applied inappropriately or too late, resulting in excess N being lost to the environment, or too little N to meet crop demand. To promote greater N use efficiency and improve agricultural sustainability, we developed an Internet of Things (IoT) approach for the real-time measurement of soil nitrate levels using ion-selective membrane sensors in combination with digital soil moisture probes. The node incorporates state-of-the-art IoT connectivity using a LoRaWAN transceiver. The sensing platform can transfer real-time data via a cloud-connected gateway for processing and storage. In summary, we present a validated soil sensor system for real-time monitoring of soil nitrate concentrations, which can support fertiliser management decisions, improve N use efficiency and reduce N losses to the environment.<\/jats:p>","DOI":"10.3390\/s22239100","type":"journal-article","created":{"date-parts":[[2022,11,24]],"date-time":"2022-11-24T03:58:16Z","timestamp":1669262296000},"page":"9100","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Development of a LoRaWAN IoT Node with Ion-Selective Electrode Soil Nitrate Sensors for Precision Agriculture"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6783-6089","authenticated-orcid":false,"given":"Noel","family":"Bristow","sequence":"first","affiliation":[{"name":"School of Computer Science and Electronic Engineering, Bangor University, Bangor LL57 1UT, UK"}]},{"given":"Saravanan","family":"Rengaraj","sequence":"additional","affiliation":[{"name":"School of Natural Sciences, Bangor University, Bangor LL57 2UW, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8479-8157","authenticated-orcid":false,"given":"David R.","family":"Chadwick","sequence":"additional","affiliation":[{"name":"School of Natural Sciences, Bangor University, Bangor LL57 2UW, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1245-5286","authenticated-orcid":false,"given":"Jeff","family":"Kettle","sequence":"additional","affiliation":[{"name":"James Watt School of Engineering, University of Glasgow, Glasgow G12 8QQ, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1482-4209","authenticated-orcid":false,"given":"Davey L.","family":"Jones","sequence":"additional","affiliation":[{"name":"School of Natural Sciences, Bangor University, Bangor LL57 2UW, UK"},{"name":"SoilsWest, Centre for Sustainable Farming Systems, Food Futures Institute, Murdoch University, Murdoch, WA 6105, Australia"}]}],"member":"1968","published-online":{"date-parts":[[2022,11,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"159","DOI":"10.1038\/472159a","article-title":"Too Much of a Good Thing","volume":"472","author":"Sutton","year":"2011","journal-title":"Nature"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"2","DOI":"10.1007\/s11119-016-9456-7","article-title":"Developing a New Crop Circle Active Canopy Sensor-Based Precision Nitrogen Management Strategy for Winter Wheat in North China Plain","volume":"18","author":"Cao","year":"2017","journal-title":"Precis. 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