{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,16]],"date-time":"2026-03-16T17:13:42Z","timestamp":1773681222074,"version":"3.50.1"},"reference-count":26,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2011,5,3]],"date-time":"2011-05-03T00:00:00Z","timestamp":1304380800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A near infrared reflectance spectroscopy (NIRS) method for rapid determination of nitrogen, phosphorous and potassium in diverse meadow grasses was developed with a view towards utilizing this material for biogas production and organic fertilizer. NIRS spectra between 12,000 cm\u22121 and 4,000 cm\u22121 were used. When validated on samples from different years to those used for the calibration set, the NIRS prediction of nitrogen was considered moderately useful with R2 = 0.77, ratio of standard error of prediction to reference data range (RER) of 9.32 and ratio of standard error of prediction to standard deviation of reference data (RPD) of 2.33. Prediction of potassium was less accurate, with R2 = 0.77, RER of 6.56 and RPD of 1.45, whilst prediction of phosphorous was not considered accurate enough to be of any practical use. This work is of interest from the point of view of both the removal of excess nutrients from formerly intensively farmed areas and also for assessing the plant biomass suitability for conversion into carbon neutral energy through biogas production.<\/jats:p>","DOI":"10.3390\/s110504830","type":"journal-article","created":{"date-parts":[[2011,5,4]],"date-time":"2011-05-04T09:03:57Z","timestamp":1304499837000},"page":"4830-4839","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":27,"title":["Rapid Assessment of Mineral Concentration in Meadow Grasses by Near Infrared Reflectance Spectroscopy"],"prefix":"10.3390","volume":"11","author":[{"given":"Alastair","family":"Ward","sequence":"first","affiliation":[{"name":"Department of Biosystems Engineering, Aarhus University, Blichers All\u00e9 20, DK-8830 Tjele, Denmark"}]},{"given":"Anne Lisbeth","family":"Nielsen","sequence":"additional","affiliation":[{"name":"Natlan, Agro Business Park, Niels Pedersens All\u00e9 2, DK-8830 Tjele, Denmark"}]},{"given":"Henrik","family":"M\u00f8ller","sequence":"additional","affiliation":[{"name":"Department of Biosystems Engineering, Aarhus University, Blichers All\u00e9 20, DK-8830 Tjele, Denmark"}]}],"member":"1968","published-online":{"date-parts":[[2011,5,3]]},"reference":[{"key":"ref_1","first-page":"34","article-title":"Arealanvendelse I Danmark siden slutningen af 1800-tallet","volume":"682","author":"Levin","year":"2008","journal-title":"Dan. 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