Comparative evaluation of Freundlich and Langmuir models in characterizing Phosphorus sorption processes under Natural Rubber (Hevea brasiliences Mull) Plantation in a humid forest area of SouthWestern Nigeria

Comparative evaluation of Freundlich and Langmuir models in characterizing Phosphorus sorption processes under Natural Rubber (Hevea brasiliences Mull) Plantation in a humid forest area of SouthWestern Nigeria | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Comparative evaluation of Freundlich and Langmuir models in characterizing Phosphorus sorption processes under Natural Rubber (Hevea brasiliences Mull) Plantation in a humid forest area of SouthWestern Nigeria C. N. Idehen, E.R. Orhue, H.I Ikhazuagbe, I. K. Ugwa, I.k. Okore, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9361015/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 10 You are reading this latest preprint version Abstract Soil solution P concentration and its availability to plants are strongly influenced by soil sorption properties. This study assessed phosphorus sorption in six soil horizons (A, AB, B1, B2, Bt1, Bt2) of the Kulfo series, under rubber plantation management in South-West Nigeria. Soils were acidic (pH 4.91–5.44), with highest organic carbon in A (5.09 g kg⁻¹), available P peaking in AB (3.52 mg kg⁻¹), low amorphous Fe (0.02–0.04%) and Al (0.05–0.12%) maxima in B1/Bt1, and clay rising to 320 g kg⁻¹ in Bt2. Batch equilibrium tests at five P additions (53–216 mg L⁻¹) produced equilibrium P concentrations and adsorped P values that increased from 31.7 to 141.3 mg kg⁻¹, revealing moderate surface retention (EPC = 28.9–139.6 mg L⁻¹; Q = 24.4–76.9 mg kg⁻¹) and highest subsoil sorption (Q = 177.9 mg kg⁻¹ at EPC = 38.5 mg L⁻¹). Linearized Freundlich plots yielded asorption intensity (a) (max 58.1 mg P g⁻¹ in Bt2) and n (> 1 except in B2), while Langmuir fits gave Qₘₐₓ (max 6.02 mg kg⁻¹ in Bt1) and b (max 289 L mg⁻¹ in Bt2). Freundlich best described surface horizons (mean RMSE = 0.13) while Langmuir describes deeper layers (mean RMSE = 0.20). Correlations with clay and amorphous oxides highlighted depth-dependent adsorption mechanisms. These insights suggest horizon-specific P application strategies to overcome fixation and optimize availability in highly weathered tropical such soil. Freundlich model Langmuir model Kulfo series Phosphorus Hevea Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Reviews received at journal 30 Apr, 2026 Reviews received at journal 30 Apr, 2026 Reviewers agreed at journal 29 Apr, 2026 Reviewers agreed at journal 24 Apr, 2026 Reviewers agreed at journal 24 Apr, 2026 Reviewers invited by journal 24 Apr, 2026 Editor invited by journal 20 Apr, 2026 Editor assigned by journal 16 Apr, 2026 Submission checks completed at journal 16 Apr, 2026 First submitted to journal 16 Apr, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9361015","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":634248439,"identity":"6a83a259-c700-4434-88c2-f25a9dcd5d65","order_by":0,"name":"C. N. Idehen","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA6klEQVRIiWNgGAWjYBACNoYEBmYGBgkGxobDB4AETPwAEVqYG48lEKeFAaKFgYG9+YwBcVr42BMYPxfusbDnbTvzTeLnDhs5BvbDB5h5zuBxGM8DZukZzyQSZ/ac3SbZeybNmIEnLYGZ5wYeLRIJbMw8ByQSDGec3SbB23Y4sUGCx4CZ5wNhLfb29988k/xLihbGxoYzbNIIW/A5jOdhszRQS2JjwzFja9m2NGM2oF8OzsHjffn25IOfeQ7U2QOj8uHNt202cvzshw8+eHMMtxYGpLhgkQDby0AgIpEBMx4/j4JRMApGwUgGAKQATkeQj77aAAAAAElFTkSuQmCC","orcid":"","institution":"Rubber Research Institute of Nigeria","correspondingAuthor":true,"prefix":"","firstName":"C.","middleName":"N.","lastName":"Idehen","suffix":""},{"id":634248440,"identity":"69400154-ad53-4b29-b1de-631251db0939","order_by":1,"name":"E.R. 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This study assessed phosphorus sorption in six soil horizons (A, AB, B1, B2, Bt1, Bt2) of the Kulfo series, under rubber plantation management in South-West Nigeria. Soils were acidic (pH 4.91\u0026ndash;5.44), with highest organic carbon in A (5.09 g kg⁻\u0026sup1;), available P peaking in AB (3.52 mg kg⁻\u0026sup1;), low amorphous Fe (0.02\u0026ndash;0.04%) and Al (0.05\u0026ndash;0.12%) maxima in B1/Bt1, and clay rising to 320 g kg⁻\u0026sup1; in Bt2. Batch equilibrium tests at five P additions (53\u0026ndash;216 mg L⁻\u0026sup1;) produced equilibrium P concentrations and adsorped P values that increased from 31.7 to 141.3 mg kg⁻\u0026sup1;, revealing moderate surface retention (EPC\u0026thinsp;=\u0026thinsp;28.9\u0026ndash;139.6 mg L⁻\u0026sup1;; Q\u0026thinsp;=\u0026thinsp;24.4\u0026ndash;76.9 mg kg⁻\u0026sup1;) and highest subsoil sorption (Q\u0026thinsp;=\u0026thinsp;177.9 mg kg⁻\u0026sup1; at EPC\u0026thinsp;=\u0026thinsp;38.5 mg L⁻\u0026sup1;). Linearized Freundlich plots yielded asorption intensity (a) (max 58.1 mg P g⁻\u0026sup1; in Bt2) and n (\u0026gt;\u0026thinsp;1 except in B2), while Langmuir fits gave Qₘₐₓ (max 6.02 mg kg⁻\u0026sup1; in Bt1) and b (max 289 L mg⁻\u0026sup1; in Bt2). Freundlich best described surface horizons (mean RMSE\u0026thinsp;=\u0026thinsp;0.13) while Langmuir describes deeper layers (mean RMSE\u0026thinsp;=\u0026thinsp;0.20). Correlations with clay and amorphous oxides highlighted depth-dependent adsorption mechanisms. These insights suggest horizon-specific P application strategies to overcome fixation and optimize availability in highly weathered tropical such soil.\u003c/p\u003e","manuscriptTitle":"Comparative evaluation of Freundlich and Langmuir models in characterizing Phosphorus sorption processes under Natural Rubber (Hevea brasiliences Mull) Plantation in a humid forest area of SouthWestern Nigeria","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-05-05 12:12:16","doi":"10.21203/rs.3.rs-9361015/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"editorInvitedReview","content":"","date":"2026-04-30T20:17:25+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-30T07:20:47+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"212562905774462392161982971642792952772","date":"2026-04-29T16:03:12+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"47412104583748980065832505094465735270","date":"2026-04-24T15:02:19+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"60667827538154021648414315023294364450","date":"2026-04-24T15:00:42+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-04-24T14:55:28+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2026-04-20T10:03:43+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-04-16T22:23:30+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-04-16T17:32:29+00:00","index":"","fulltext":""},{"type":"submitted","content":"Discover Soil","date":"2026-04-16T17:28:08+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"discover-soil","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"Learn more about [Discover Soil](https://link.springer.com/journal/44378)","snPcode":"44378","submissionUrl":"https://submission.nature.com/new-submission/44378/3","title":"Discover Soil","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Discover Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"8f2243b2-71af-4136-9946-256f894a259e","owner":[],"postedDate":"May 5th, 2026","published":true,"recentEditorialEvents":[{"type":"editorInvitedReview","content":"","date":"2026-04-30T20:17:25+00:00","index":35,"fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-30T07:20:47+00:00","index":34,"fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-05-05T12:12:16+00:00","versionOfRecord":[],"versionCreatedAt":"2026-05-05 12:12:16","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9361015","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9361015","identity":"rs-9361015","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}