{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,1]],"date-time":"2026-02-01T01:00:49Z","timestamp":1769907649798,"version":"3.49.0"},"reference-count":40,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2021,3,3]],"date-time":"2021-03-03T00:00:00Z","timestamp":1614729600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sustainability"],"abstract":"<jats:p>The Montado is an agro-silvo-pastoral ecosystem characteristic of the Mediterranean region. Pasture productivity and, consequently, the possibilities for intensifying livestock production depend on soil fertility. Soil organic matter (SOM) and phosphorus (P2O5) are two indicators of the evolution of soil fertility in this ecosystem. However, their conventional analytical determination by reference laboratory methods is costly, time consuming, and laborious and, thus, does not meet the needs of current production systems. The aim of this study was to evaluate an alternative approach to estimate SOM and soil P2O5 based on near infrared spectroscopy (NIRS) combined with multivariate data analysis. For this purpose, 242 topsoil samples were collected in 2019 in eleven fields. These samples were subjected to reference laboratory analysis and NIRS analysis. For NIRS, 165 samples were used during the calibration phase and 77 samples were used during the external validation phase. The results of this study showed significant correlation between NIRS calibration models and reference methods for quantification of these soil parameters. The coefficient of determination (R2, 0.85 for SOM and 0.76 for P2O5) and the residual predictive deviation (RPD, 2.7 for SOM and 2.2 for P2O5) obtained in external validation indicated the potential of NIRS to estimate SOM and P2O5, which can facilitate farm managers\u2019 decision making in terms of dynamic management of animal grazing and differential fertilizer application.<\/jats:p>","DOI":"10.3390\/su13052734","type":"journal-article","created":{"date-parts":[[2021,3,3]],"date-time":"2021-03-03T20:33:57Z","timestamp":1614803637000},"page":"2734","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Evaluation of Near Infrared Spectroscopy (NIRS) for Estimating Soil Organic Matter and Phosphorus in Mediterranean Montado Ecosystem"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5178-8158","authenticated-orcid":false,"given":"Jo\u00e3o","family":"Serrano","sequence":"first","affiliation":[{"name":"MED\u2014Mediterranean Institute for Agriculture, Environment and Development, Instituto de Investiga\u00e7\u00e3o e Forma\u00e7\u00e3o Avan\u00e7ada, Universidade de \u00c9vora, P\u00f3lo da Mitra, Ap. 94, 7006-554 \u00c9vora, Portugal"}]},{"given":"Shakib","family":"Shahidian","sequence":"additional","affiliation":[{"name":"MED\u2014Mediterranean Institute for Agriculture, Environment and Development, Instituto de Investiga\u00e7\u00e3o e Forma\u00e7\u00e3o Avan\u00e7ada, Universidade de \u00c9vora, P\u00f3lo da Mitra, Ap. 94, 7006-554 \u00c9vora, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0305-8147","authenticated-orcid":false,"given":"Jos\u00e9","family":"Marques da Silva","sequence":"additional","affiliation":[{"name":"MED\u2014Mediterranean Institute for Agriculture, Environment and Development, Instituto de Investiga\u00e7\u00e3o e Forma\u00e7\u00e3o Avan\u00e7ada, Universidade de \u00c9vora, P\u00f3lo da Mitra, Ap. 94, 7006-554 \u00c9vora, Portugal"},{"name":"AgroInsider Lda. PITE, R. Circular Norte, NERE, Sala 18, 7005-841 \u00c9vora, Portugal"}]},{"given":"Lu\u00eds","family":"Paix\u00e3o","sequence":"additional","affiliation":[{"name":"AgroInsider Lda. PITE, R. Circular Norte, NERE, Sala 18, 7005-841 \u00c9vora, Portugal"}]},{"given":"M\u00e1rio","family":"de Carvalho","sequence":"additional","affiliation":[{"name":"MED\u2014Mediterranean Institute for Agriculture, Environment and Development, Instituto de Investiga\u00e7\u00e3o e Forma\u00e7\u00e3o Avan\u00e7ada, Universidade de \u00c9vora, P\u00f3lo da Mitra, Ap. 94, 7006-554 \u00c9vora, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8465-1318","authenticated-orcid":false,"given":"Francisco","family":"Moral","sequence":"additional","affiliation":[{"name":"Departamento de Expresi\u00f3n Gr\u00e1fica, Escuela de Ingenier\u00edas Industriales, Universidad de Extremadura Avenida de Elvas s\/n, 06006 Badajoz, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3092-4349","authenticated-orcid":false,"given":"Julio","family":"Nogales-Bueno","sequence":"additional","affiliation":[{"name":"Food Colour and Quality Laboratory, \u00c1rea de Nutrici\u00f3n y Bromatologia, Facultad de Farmacia, Universidad de Sevilla, 41012 Sevilla, Spain"},{"name":"Department of Animal Production, Campus of Rabanales, University of Cordoba, 14072 C\u00f3rdoba, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9915-6264","authenticated-orcid":false,"given":"Ricardo F.M.","family":"Teixeira","sequence":"additional","affiliation":[{"name":"MARETEC\u2014Marine, Environment and Technology Centre, LARSyS, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais, 1, 1049-001 Lisbon, Portugal"}]},{"given":"Marjan","family":"Jongen","sequence":"additional","affiliation":[{"name":"MARETEC\u2014Marine, Environment and Technology Centre, LARSyS, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais, 1, 1049-001 Lisbon, Portugal"},{"name":"CEF-Centro de Estudos Florestais, Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6194-0405","authenticated-orcid":false,"given":"Tiago","family":"Domingos","sequence":"additional","affiliation":[{"name":"MARETEC\u2014Marine, Environment and Technology Centre, LARSyS, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais, 1, 1049-001 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5267-3723","authenticated-orcid":false,"given":"Ana Elisa","family":"Rato","sequence":"additional","affiliation":[{"name":"MED\u2014Mediterranean Institute for Agriculture, Environment and Development, Instituto de Investiga\u00e7\u00e3o e Forma\u00e7\u00e3o Avan\u00e7ada, Universidade de \u00c9vora, P\u00f3lo da Mitra, Ap. 94, 7006-554 \u00c9vora, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,3,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.agee.2013.01.002","article-title":"Soil organic matter content and composition as influenced by soil management in a semi-arid Mediterranean agro-silvo-pastoral system","volume":"167","author":"Seddaiu","year":"2013","journal-title":"Agric. Ecosyst. Environ."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"274","DOI":"10.1007\/s11119-015-9419-4","article-title":"Monitoring of soil organic carbon over 10 years in a Mediterranean silvo-pastoral system: Potential evaluation for differential management","volume":"17","author":"Serrano","year":"2016","journal-title":"Prec. Agric."},{"key":"ref_3","first-page":"59","article-title":"Mapping soil organic matter contents at field level with Cubist, Random Forest and kriging","volume":"131","author":"Pouladia","year":"2006","journal-title":"Geoderma"},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Shen, L., Gao, M., Yan, J., Li, Z.-L., Leng, P., Yang, Q., and Duan, S.B. (2020). Hyperspectral estimation of soil organic matter content using different spectral preprocessing techniques and PLSR method. Remote Sens., 12.","DOI":"10.3390\/rs12071206"},{"key":"ref_5","unstructured":"Universidade de \u00c9vora\u2014ICAM (2006). Pastures in Alentejo: Technical Basis for Characterization, Grazing and Improvement, Gr\u00e1fica Eborense."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"63","DOI":"10.1007\/s10705-010-9412-2","article-title":"Phosphorus dynamics in permanent pastures: Differential fertilizing and the animal effect","volume":"90","author":"Serrano","year":"2011","journal-title":"Nutr. Cycl. Agroecosyst."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"629","DOI":"10.1111\/j.1365-2389.2011.01358.x","article-title":"Calibration of visible and near infrared spectroscopy for soil analysis at the field scale on three European farms","volume":"62","author":"Kuang","year":"2011","journal-title":"Eur. J. Soil Sci."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"990","DOI":"10.1590\/S1516-35982008000600006","article-title":"Concentrations and amounts of macronutrients in the animal dung grazing Panicum maximum fertilized with phosphorous","volume":"37","author":"Rodrigues","year":"2008","journal-title":"R. Bras. Zoot."},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Jiang, Q., Chen, Y., Guo, L., Fei, T., and Qi, K. (2016). Estimating soil organic carbon of Cropland soil at different levels of soil moisture using VIS-NIR spectroscopy. Remote Sens., 8.","DOI":"10.3390\/rs8090755"},{"key":"ref_10","first-page":"199","article-title":"Utersuchungeniiber die chemische Bodenanalyse als Grudlagefir die Beurteilung des Nahrstof-zunstandes der Boden. II","volume":"20","author":"Egner","year":"1960","journal-title":"K. Lantbr. Ann."},{"key":"ref_11","first-page":"126","article-title":"Sensor systems for mapping soil fertility attributes: Challenges, advances, and perspectives in Brazilian tropical soils","volume":"39","author":"Molin","year":"2019","journal-title":"Eng. Agric."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Nawar, S., Munnaf, M.A., and Mouazen, A.M. (2020). Machine learning based on-line prediction of soil organic carbon after removal of soil moisture effect. Remote Sens., 12.","DOI":"10.3390\/rs12081308"},{"key":"ref_13","unstructured":"FAO (2006). World Reference Base for Soil Resources, Food and Agriculture Organization of the United Nations. World Soil Resources Reports N \u00c6 103."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Serrano, J., Shahidian, S., da Silva, J.M., Paix\u00e3o, L., Carreira, E., Pereira, A., and Carvalho, M. (2020). Climate changes challenges to the management of Mediterranean Montado ecosystem: Perspectives for use of precision agriculture technologies. Agronomy, 10.","DOI":"10.3390\/agronomy10020218"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1800392","DOI":"10.1002\/ejlt.201800392","article-title":"Rapid assessment of monovarietal portuguese Extra Virgin Olive Oil\u2019s (EVOO\u2019s) fatty acids by Fourier-Transform Near-Infrared Spectroscopy (FT-NIRS)","volume":"121","author":"Milinovic","year":"2020","journal-title":"Eur. J. Lipid Sci. Technol."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"109","DOI":"10.1016\/S0169-7439(01)00155-1","article-title":"PLS-regression: A basic tool of chemometrics","volume":"58","author":"Wold","year":"2001","journal-title":"Chemometr. Intell. Lab. Syst."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"11","DOI":"10.1016\/j.foodcont.2017.09.014","article-title":"Phenolic profiling of grapes, fermenting samples and wines using UV-Visible spectroscopy with chemometrics","volume":"85","author":"Nieuwoudt","year":"2018","journal-title":"Food Control."},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Donis-Gonz\u00e1lez, I.R., Valero, C., Momin, M.A., Kaur, A., and Slaughter, D.C. (2020). Performance evaluation of two commercially available portable spectrometers to non-invasively determine table grape and peach quality attributes. Agronomy, 10.","DOI":"10.3390\/agronomy10010148"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"114009","DOI":"10.1016\/j.geoderma.2019.114009","article-title":"Predicting glyphosate sorption across New Zealand pastoral soils using basic soil properties or Vis\u2013NIR spectroscopy","volume":"360","author":"Hermansen","year":"2020","journal-title":"Geoderma"},{"key":"ref_20","first-page":"518","article-title":"Manganese toxicity in Portuguese Cambisols derived from granitic rocks: Causes, limitations of soil analyses and possible solutions","volume":"38","author":"Carvalho","year":"2015","journal-title":"Rev. Cienc. Agr\u00e1rias"},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Serrano, J., Shahidian, S., da Silva, J.M., Moral, F., Carvajal-Ramirez, F., Carreira, E., Pereira, A., and Carvalho, M. (2020). Evaluation of the effect of dolomitic lime application on pastures\u2014Case study in the Montado Mediterranean ecosystem. Sustainability, 12.","DOI":"10.3390\/su12093758"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"103","DOI":"10.1007\/s10705-017-9903-5","article-title":"The long-term role of organic amendments in building soil nutrient fertility: A meta-analysis and review","volume":"111","author":"Chen","year":"2018","journal-title":"Nutr. Cycl. Agroecosyst."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"443","DOI":"10.1007\/s13593-014-0212-y","article-title":"Soil organic carbon sequestration in agroforestry systems. A review","volume":"34","author":"Lorenz","year":"2014","journal-title":"Agron. Sustain. Dev."},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Ordo\u00f1ez, M.-C., Olaya, J.F.C., Galicia, L., and Figueroa, A. (2020). Soil Carbon Dynamics under Pastures in Andean Socio-Ecosystems of Colombia. Agronomy, 10.","DOI":"10.3390\/agronomy10040507"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"993","DOI":"10.1016\/j.ecolmodel.2010.11.013","article-title":"Soil organic matter dynamics in Portuguese natural and sown rainfed grasslands","volume":"222","author":"Teixeira","year":"2011","journal-title":"Ecol. Modell."},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Vaudour, E., Gomez, C., Loiseau, T., Baghdadi, N., Loubet, B., Arrouays, D., Ali, L., and Lagacherie, P. (2019). The Impact of Acquisition Date on the Prediction Performance of Topsoil Organic Carbon from Sentinel-2 for Croplands. Remote Sens., 11.","DOI":"10.3390\/rs11182143"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"59","DOI":"10.1016\/j.geoderma.2005.03.007","article-title":"Visible, near infrared, mid infrared or combined diffuse reflectance spectroscopy for simultaneous assessment of various soil properties","volume":"131","author":"Rossel","year":"2006","journal-title":"Geoderma"},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Zizala, D., Minank, R., and Z\u00e1dorov\u00e1, T. (2019). Soil organic carbon mapping using multispectral remote sensing data: Prediction ability of data with different spatial and spectral resolutions. Remote Sens., 11.","DOI":"10.3390\/rs11242947"},{"key":"ref_29","first-page":"729","article-title":"Application in analysis of soils","volume":"Volume 44","author":"Roberts","year":"2004","journal-title":"Near-Infrared Spectroscopy in Agriculture"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"305","DOI":"10.1016\/j.biosystemseng.2005.04.015","article-title":"Spectral phosphorus mapping using diffuse reflectance of soils and grass","volume":"91","author":"Bogrekci","year":"2005","journal-title":"Biosyst. Eng."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"425","DOI":"10.1016\/j.biosystemseng.2006.07.015","article-title":"Phosphorus sensing for fresh soils using visible and near infrared spectroscopy","volume":"95","author":"Maleki","year":"2006","journal-title":"Biosyst. Eng."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"471","DOI":"10.1016\/j.still.2015.04.003","article-title":"On-line visible and near infrared spectroscopy for in-field phosphorous management","volume":"155","author":"Mouazen","year":"2016","journal-title":"Soil Till. Res."},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Kawamura, K., Tsujimoto, Y., Nishigaki, T., Andriamananjara, A., Rabenarivo, M., Asai, H., and Razafimbelo, T. (2019). Laboratory visible and near-infrared spectroscopy with genetic algorithm-based partial least squares regression for assessing the soil phosphorus content of upland and lowland rice fields in Madagascar. Remote Sens., 11.","DOI":"10.3390\/rs11050506"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"737","DOI":"10.1007\/s11119-019-09693-3","article-title":"Predicting plant available phosphorus using infrared spectroscopy with consideration for future mobile sensing applications in precision farming","volume":"21","author":"Patzold","year":"2020","journal-title":"Prec. Agric."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"1965","DOI":"10.1080\/00103620701548498","article-title":"Measurement of phosphorus in soils by near infrared reflectance spectroscopy: Effect of reference method on calibration","volume":"38","author":"Cozzolino","year":"2007","journal-title":"Commun. Soil Sci. Plant. Anal."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"3415","DOI":"10.5194\/bg-12-3415-2015","article-title":"Use of near-infrared spectroscopy to assess phosphorus fractions of different plant availability in forest soils","volume":"12","author":"Niederberger","year":"2015","journal-title":"Biogeosciences"},{"key":"ref_37","first-page":"423","article-title":"Phosphorus desorbability in soils with andic properties from the Azores, Portugal","volume":"32","author":"Auxtero","year":"2009","journal-title":"R. Ci\u00eanc. Agr\u00e1r."},{"key":"ref_38","unstructured":"Sims, J.T., Leytem, A.B., and Gartley, K.L. (2002). Interpreting Soil Phosphorus Tests, Department of Plant and Soil Sciences, College of Agriculture and Natural Resources, University of Delaware."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"131","DOI":"10.1023\/B:PRAG.0000022358.24102.1b","article-title":"Efficacy of grid and zone soil sampling approaches for site-specific assessment of phosphorus, potassium, pH, and organic matter","volume":"5","author":"Mallarino","year":"2004","journal-title":"Prec. Agric."},{"key":"ref_40","doi-asserted-by":"crossref","unstructured":"Castaldi, F., Chabrillat, S., Don, A., and Van Wesemael, B. (2019). Soil organic carbon mapping using LUCAS topsoil database and Sentinel-2 data: An approach to reduce soil moisture and crop residue effects. Remote Sens., 11.","DOI":"10.3390\/rs11182121"}],"container-title":["Sustainability"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2071-1050\/13\/5\/2734\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T05:32:12Z","timestamp":1760160732000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2071-1050\/13\/5\/2734"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,3,3]]},"references-count":40,"journal-issue":{"issue":"5","published-online":{"date-parts":[[2021,3]]}},"alternative-id":["su13052734"],"URL":"https:\/\/doi.org\/10.3390\/su13052734","relation":{},"ISSN":["2071-1050"],"issn-type":[{"value":"2071-1050","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,3,3]]}}}