{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,4]],"date-time":"2026-02-04T18:00:42Z","timestamp":1770228042739,"version":"3.49.0"},"reference-count":70,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2024,7,11]],"date-time":"2024-07-11T00:00:00Z","timestamp":1720656000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Yield Gap project","award":["135PR007"],"award-info":[{"award-number":["135PR007"]}]},{"name":"UM6P","award":["135PR007"],"award-info":[{"award-number":["135PR007"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Total nitrogen (TN) is a critical nutrient for plant growth, and its monitoring in agricultural soil is vital for farm managers. Traditional methods of estimating soil TN levels involve laborious and costly chemical analyses, especially when applied to large areas with multiple sampling points. Remote sensing offers a promising alternative for identifying, tracking, and mapping soil TN levels at various scales, including the field, landscape, and regional levels. Spaceborne hyperspectral sensing has shown effectiveness in reflecting soil TN levels. This study evaluates the efficiency of spectral reflectance at visible near-infrared (VNIR) and shortwave near-infrared (SWIR) regions to identify the most informative hyperspectral bands responding to the TN content in agricultural soil. In this context, we used PRISMA (PRecursore IperSpettrale della Missione Applicativa) hyperspectral imagery with ensemble learning modeling to identify N-specific absorption features. This ensemble consisted of three multivariate regression techniques, partial least square (PLSR), support vector regression (SVR), and Gaussian process regression (GPR) learners. The soil TN data (n = 803) were analyzed against a hyperspectral PRISMA imagery to perform spectral band selection. The 803 sampled data points were derived from open-access soil property and nutrient maps for Africa at a 30 m resolution over a bare agricultural field in southern Morocco. The ensemble learning strategy identified several bands in the SWIR in the regions of 900\u20131300 nm and 1900\u20132200 nm. The models achieved coefficient-of-determination values ranging from 0.63 to 0.73 and root-mean-square error values of 0.14 g\/kg for PLSR, 0.11 g\/kg for SVR, and 0.12 g\/kg for GPR, which had been boosted to an R2 of 0.84, an RMSE of 0.08 g\/kg, and an RPD of 2.53 by the ensemble, demonstrating the model\u2019s accuracy in predicting the soil TN content. These results underscore the potential for using spaceborne hyperspectral imagery for soil TN estimation, enabling the development of decision-support tools for variable-rate fertilization and advancing our understanding of soil spectral responses for improved soil management.<\/jats:p>","DOI":"10.3390\/rs16142549","type":"journal-article","created":{"date-parts":[[2024,7,11]],"date-time":"2024-07-11T11:33:22Z","timestamp":1720697602000},"page":"2549","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Ensemble Band Selection for Quantification of Soil Total Nitrogen Levels from Hyperspectral Imagery"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1443-3926","authenticated-orcid":false,"given":"Khalil","family":"Misbah","sequence":"first","affiliation":[{"name":"Center for Remote Sensing Applications (CRSA), Mohammed VI Polytechnic University (UM6P), Benguerir 43150, Morocco"},{"name":"Department of Agriculture Forestry and Nature (DAFNE), University of Tuscia, 01100 Viterbo, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6603-5025","authenticated-orcid":false,"given":"Ahmed","family":"Laamrani","sequence":"additional","affiliation":[{"name":"Center for Remote Sensing Applications (CRSA), Mohammed VI Polytechnic University (UM6P), Benguerir 43150, Morocco"}]},{"given":"Paul","family":"Voroney","sequence":"additional","affiliation":[{"name":"School of Environmental Sciences, University of Guelph, Guelph, ON N1G 2W1, Canada"}]},{"given":"Keltoum","family":"Khechba","sequence":"additional","affiliation":[{"name":"Center for Remote Sensing Applications (CRSA), Mohammed VI Polytechnic University (UM6P), Benguerir 43150, Morocco"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3091-7680","authenticated-orcid":false,"given":"Raffaele","family":"Casa","sequence":"additional","affiliation":[{"name":"Department of Agriculture Forestry and Nature (DAFNE), University of Tuscia, 01100 Viterbo, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0270-1690","authenticated-orcid":false,"given":"Abdelghani","family":"Chehbouni","sequence":"additional","affiliation":[{"name":"Center for Remote Sensing Applications (CRSA), Mohammed VI Polytechnic University (UM6P), Benguerir 43150, Morocco"},{"name":"Institut de Recherche Pour le D\u00e9veloppement (IRD), Unit\u00e9 Mixte de Recherche (UMR), Centre D\u2019\u00e9tudes Spatiales de la Biosph\u00e8re, Cesbio, 31401 Toulouse, France"}]}],"member":"1968","published-online":{"date-parts":[[2024,7,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"546","DOI":"10.1016\/j.geoderma.2018.11.036","article-title":"Yield-Limiting Macronutrients for Rice in Sub-Saharan Africa","volume":"338","author":"Saito","year":"2019","journal-title":"Geoderma"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"387","DOI":"10.1016\/j.pce.2010.03.030","article-title":"Growth and Yield Responses of Crops and Macronutrient Balance Influenced by Commercial Organic Manure Used as a Partial Substitute for Chemical Fertilizers in an Intensive Vegetable Cropping System","volume":"36","author":"Lu","year":"2011","journal-title":"Phys. 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