Geoderma Regional最新文献

{"title":"Soil carbon stocks in cultivated Luvisols respond positively to long-term agronomic practices with different degrees of perennial forage inclusion","authors":"Jamin N. Achtymichuk ,&nbsp;Miles F. Dyck ,&nbsp;Sylvie A. Quideau ,&nbsp;Erick R.S. Santos ,&nbsp;Dick Puurveen ,&nbsp;Scott R. Jeffrey ,&nbsp;Edward W. Bork","doi":"10.1016/j.geodrs.2025.e01025","DOIUrl":"10.1016/j.geodrs.2025.e01025","url":null,"abstract":"<div><div>Data that are relevant, substantive, and reliable are needed to verify long-term management effects on carbon (C) stocks in agricultural soils. The Breton Plots research facility in West Central Alberta, Canada, provides a unique opportunity to investigate how diverse long-term agricultural practices have influenced C storage in low-fertility Luvisolic soils from boreal regions. The Classical Plots experiment (est. 1930) includes unamended, conventionally fertilized, and manured sub-treatments of a wheat-fallow and 5-year rotation comprising annual grains (3 yr) and perennial forage (2 yr). The Hendrigan Plots experiment (est. 1980) includes a continuous forage system; a continuous grain system; and an 8-year agroecological rotation of annual grains (4 yr), leguminous green manure (1 yr), and perennial forage (3 yr). Soil organic carbon (SOC) stocks were reported on an equivalent soil mass basis in various intervals corresponding to a maximum depth of 90 cm. Compared to continuous grain cropping, total SOC stock was 49 % lower under fallow and, on average, 9 % higher under forage-inclusive rotations. Compared to unamended treatments, conventional fertilizer and manure increased SOC stocks by an average of 7 % and 39 %, respectively. Compared to continuous grain cropping, using the 2024 valuation of carbon ($80 t CO₂-e⁻¹) in Canada, SOC stock differences translated into a loss of approximately $11,000 CAD ha⁻¹ under fallow, and gains exceeding $5000 CAD ha⁻¹ under continuous forage or agroecological management. This work clarifies how Luvisolic soils can be managed to optimize SOC stocks and how C valuation could incentivize agricultural practices conducive to this goal.</div></div>","PeriodicalId":56001,"journal":{"name":"Geoderma Regional","volume":"43 ","pages":"Article e01025"},"PeriodicalIF":3.3,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145467012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Soil inorganic carbon variations and thresholds of occurrence in an arid and semi-arid zone","authors":"Jin Hu ,&nbsp;Xiao-Dong Song ,&nbsp;Fei Yang ,&nbsp;Shun-Hua Yang ,&nbsp;Jin-Ling Yang ,&nbsp;Gan-Lin Zhang","doi":"10.1016/j.geodrs.2025.e01023","DOIUrl":"10.1016/j.geodrs.2025.e01023","url":null,"abstract":"<div><div>Soil inorganic carbon (SIC) accounts for up to half of the global soil carbon stock and is mainly distributed in arid and semi-arid areas. However, our understanding on the drivers of vertical and spatial variations in SIC remains uncertain due to strong heterogeneity and data limitations. In this study, we conducted soil investigations across arid and semi-arid zones with climate gradients and surveyed 365 soil profiles. Statistical analysis, Shapley additive explanations and threshold detection were employed to quantify SIC variations and correlations between SIC and predictors. The average SIC density in this region was 2.78 kg/m², which was more abundant at depths of 40–120 cm (3.34 kg/m²) than at 0–20 cm (1.31 kg/m²). Soil pH, depth and aridity were the key drivers of SIC variation, with the highest mean absolute Shapley values of 1.00, 0.63 and 0.35, respectively. The pH threshold affecting SIC variation was 7.7. Thresholds for SIC distribution occurred in both vertical and horizontal dimensions. Depths of initial SIC deposition are generally increase as aridity decreases, which was 28, 43 and 46 cm, with enhanced, reduced and uniform deposition occurring below this depth thresholds under hyper arid, arid and semi-arid zone, respectively. Aridity values below 0.62 marked SIC loss threshold at depths of 0–20 cm, whereas above 0.78 signified stable SIC accumulation threshold at depths of 20–40 cm. This research provides new insights into SIC formation and decomposition and benchmarks for modeling SIC dynamics in the context of climate change.</div></div>","PeriodicalId":56001,"journal":{"name":"Geoderma Regional","volume":"43 ","pages":"Article e01023"},"PeriodicalIF":3.3,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145417463","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Soil fertility characterization in Brazilian pastures through soil chemical and physical analysis","authors":"João Paulo da Silva ,&nbsp;Jurandir Zullo Junior ,&nbsp;Luciana Alvim Santos Romani ,&nbsp;Eduardo Delgado Assad","doi":"10.1016/j.geodrs.2025.e01010","DOIUrl":"10.1016/j.geodrs.2025.e01010","url":null,"abstract":"<div><div>Brazil is largely occupied by pastures under varying conditions, rising needs for systematic assessment of soil fertility and improvement of management strategies. Soil analyses are valuable tools for fertility assessment, but its use can be amplified to foster information exchanges between farmers, service providers and fertilizer vendors in broader scales. So, our objective was to characterize the fertility dynamic of Brazilian pastures through its soil chemical and physical properties. We employed soil analysis results collected from different land uses (pasture, integrated system, and native vegetation), soil depths (0–5 cm, 5–10 cm, 10–20 cm, and 20–30 cm) and textural classes extracted from the Brazilian Soil Classification System to determine Land Use Fertility Profiles based on two core dimensions representing soil fertility and acidity, addressing 35 % and 24 % of the total variance, respectively. Stratified comparisons showed that the acidity dimension distinguished native vegetation from integrated system soils; fertility differences between textural groups in superficial layers were more frequent among pastures samples than among integrated systems ones and diminished in depth. The acidity dimension remained differing sandy and medium texture soils from clayey and heavy clayey ones. In the crossed comparisons, our results indicated that sandy soils under pasture concentrate their heterogeneity in deeper layers (20–30 cm). Thus, sampling schemes should be conducted up to these depths to improve efficiency in management strategies. This approach aimed at contributing to the data-modeling scope of agribusiness digital transformation and to the global agenda for sustainable food supply by enhancing soil fertility efficiency.</div></div>","PeriodicalId":56001,"journal":{"name":"Geoderma Regional","volume":"43 ","pages":"Article e01010"},"PeriodicalIF":3.3,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145222457","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Conventional and industrial by-product fertilization do not induce greenhouse gas emissions in sandy soils under wild lowbush blueberry cropping in eastern Canada","authors":"Anthony J. Pelletier ,&nbsp;Patrick Faubert ,&nbsp;Jean Lafond ,&nbsp;Normand Bertrand ,&nbsp;Jean Legault ,&nbsp;Rock Ouimet ,&nbsp;David E. Pelster ,&nbsp;André Pichette ,&nbsp;Noura Ziadi ,&nbsp;Maxime C. Paré","doi":"10.1016/j.geodrs.2025.e01024","DOIUrl":"10.1016/j.geodrs.2025.e01024","url":null,"abstract":"<div><div>Greenhouse gas (GHG) emissions from wild lowbush blueberry (WLB) production after fertilization with conventional mineral (MIN) and organic (ORG) or industrial pulp and paper mill sludge (PPMS) and synthetic anhydrite (SA; calcic amendment; CaSO₄) remain unknown. We assessed nitrous oxide (N₂O) and methane (CH₄) emissions following application of combined PPMS and SA under WLB production compared to MIN and ORG fertilizers during a two-year cropping cycle. A 50 kg nitrogen (N) ha⁻¹ recommended input was broadcasted before stem emergence during the pruning phase with MIN, ORG, and PPMS treatments alongside an unfertilized control (0 N; CTL). The PPMS treatment was also combined with SA as 6 Mg ha⁻¹ (1SA) and 12 Mg ha⁻¹ (2SA) inputs, which were also applied alone for a total of eight treatments. The GHG emissions were monitored using non-flow-through, non-steady-state chambers during two growing seasons. The N₂O and CH₄ emissions were unaffected by fertilizer applications. The N₂O emissions were significantly higher during the pruning phase (0.06 ± 0.009 kg N₂O-N ha⁻¹ yr⁻¹) than during the harvesting phase (0.03 ± 0.005 kg N₂O-N ha⁻¹ yr⁻¹). The fertilizer-induced emission factor (FIEF) values (−0.01 ± 0.02 %) were much lower than the default 1 % used for GHG inventories. A CH₄ uptake was observed during both growing seasons, with higher uptake during the pruning phase (−2.1 ± 0.1 kg CH₄-C ha⁻¹ yr⁻¹) than in the harvesting phase (−1.6 ± 0.1 kg CH₄-C ha⁻¹ yr⁻¹). High aeration of sandy soils combined with low soil NO₃ contents (0.9 μg NO₃-N cm⁻² yr⁻¹ during the pruning phase) might constrain N₂O emissions. Proposed WLB-specific FIEF should be used in future GHG inventories to prevent emission overestimates. Further research is needed on the agronomic benefits and yield effects of combining PPMS and SA for WLB productivity.</div></div>","PeriodicalId":56001,"journal":{"name":"Geoderma Regional","volume":"43 ","pages":"Article e01024"},"PeriodicalIF":3.3,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145467013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhancing “Campos” grassland productivity by improving soil fertility and overseeding: A meta-analysis","authors":"João Pedro Moro Flores ,&nbsp;Dionata Filippi ,&nbsp;Lucas Aquino Alves ,&nbsp;Gustavo Pesini ,&nbsp;Leandro Bittencourt de Oliveira ,&nbsp;Geraldo José Rodrigues ,&nbsp;Carlos Nabinger ,&nbsp;Fernando Luiz Ferreira De Quadros ,&nbsp;Tales Tiecher","doi":"10.1016/j.geodrs.2025.e01014","DOIUrl":"10.1016/j.geodrs.2025.e01014","url":null,"abstract":"<div><div>Enhancing forage and beef productivity in natural grasslands is essential to prevent their conversion into annual crops, planted pastures, and forests. This strategy is pivotal for preserving ecological balance and promoting biodiversity conservation. The present meta-analysis assesses the effects of various improvement technologies on forage and animal production in southern Brazil's natural grasslands. These technologies include liming, fertilization with N, P, K, and S, and the overseeding of exogenous forage species, with a focus on enhancing soil chemical parameters and forage production. A total of 506 sample pairs were compiled from 49 studies conducted between 1967 and 2020. The natural grassland without fertilization and/or overseeding served as the control. Each pair of observations compared the control to treatments involving liming, fertilization, and/or overseeding. The applied improvement technologies yielded an average increase of 44 % in forage production and 82 % in animal production per hectare, respectively. In studies that focused exclusively on forage productivity, the average increase was 34 % compared to the control. Natural grasslands on soils with lower innate fertility, such as Arenosol, Acrisol, Planosol, or Plinthosol, exhibited a more substantial response (+98 %) when doses of N + P + K + S exceeded 234 kg ha⁻¹. In contrast, soils with higher natural fertility, including Leptosol/Regosol, Nitisol, Ferrasol, Luvisol, and Vertisol, showed increases ranging from +6 to +36 % compared to the control. These findings indicate that focusing improvement technologies on natural grasslands developed on soils with significant chemical constraints is beneficial. Moreover, to sustain natural grasslands, incorporating management of cool-season species while tailoring soil fertility to maximize forage and animal productivity is recommended.</div></div>","PeriodicalId":56001,"journal":{"name":"Geoderma Regional","volume":"43 ","pages":"Article e01014"},"PeriodicalIF":3.3,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145325619","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantifying CO2 emissions from Quebec's agricultural peatland and identifying key parameters for guiding soil conservation strategies","authors":"Félix L'Heureux-Bilodeau ,&nbsp;Jacynthe Dessureault-Rompré ,&nbsp;Alain N. Rousseau ,&nbsp;Jean Caron","doi":"10.1016/j.geodrs.2025.e01015","DOIUrl":"10.1016/j.geodrs.2025.e01015","url":null,"abstract":"<div><div>In Quebec, Canada, field vegetable production largely occurs on cultivated organic soils of Montérégie. These soils become arable following extensive drainage of peatlands, which are highly fertile but vulnerable to subsidence, erosion, and organic matter mineralization. The latter causes carbon losses to the atmosphere through CO₂ emissions and can also lead to dissolved organic carbon leaching. This study quantified CO₂ emissions and identified governing edaphic and meteorological parameters to support the development of carbon compensation strategies for peatland managers. Easily measurable soil parameters were selected to provide farmers with potential proxies for routine soil analysis.</div><div>Five commercial sites were selected based on their organic matter (OM) content: F1 (52.2 %), F2 (56.7 %), F3 (74.0 %), F4 (77.4 %), and F5 (91.3 %). All sites, except F3, were devoid of vegetation. Soil CO₂ emissions were measured using manual static chambers over one year (September 2021–September 2022) at bimonthly intervals. Gross annual carbon losses were 4.94 Mg C-CO₂ ha⁻¹ yr⁻¹ for F1, 5.47 for F2, 15.30 for F3, 7.62 for F4, and 3.20 for F5.</div><div>Soil temperature, total microbiological activity (fluorescein diacetate hydrolysis), total nitrogen, and pH significantly and positively influenced CO₂ fluxes, while soil water content showed a negative correlation. Annual carbon losses were highly and exponentially correlated with total microbiological activity, underscoring its relevance as a biological indicator and promising proxy for CO₂ emissions.</div><div>This study advances understanding of CO₂ emissions from cultivated organic soils and highlights the importance of targeted strategies to mitigate carbon losses and conserve these valuable peatland resources.</div></div>","PeriodicalId":56001,"journal":{"name":"Geoderma Regional","volume":"43 ","pages":"Article e01015"},"PeriodicalIF":3.3,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145222367","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessing the performance of diffusive gradients in thin films for plant available phosphorus in northern Irish dairy farms","authors":"Rebecca L. Hall ,&nbsp;Katrina A. Macintosh ,&nbsp;Suzanne Higgins ,&nbsp;John McGrath ,&nbsp;Paul N. Williams","doi":"10.1016/j.geodrs.2025.e01027","DOIUrl":"10.1016/j.geodrs.2025.e01027","url":null,"abstract":"<div><div>Phosphorus (P) loss from agricultural land is contributing to the enrichment of surface waterbodies and is a reason why water quality in Northern Ireland (NI) is failing to meet Water Framework Directive targets. In NI the agronomic and environmental targets for soil P are based on measurements of sodium bicarbonate extractable-P (Olsen P), however, this methodology has been shown to underestimate bioavailable P in the iron and aluminium rich basalt derived soils of the Antrim Plateau, which covers approximately one third (450 km²) of the land area of NI. In our study an alternative advanced speciation method, namely Diffusive Gradients in Thin films (DGT), was used to assess P bioavailability on dairy farm soils in NI and compared it with traditional soil extractions used on the island of Ireland (Olsen P (in NI) and Morgan's P (in the Republic of Ireland). We observed variability in P status depending on soil test P (STP) method used (Olsen P, Morgan's P or DGT). DGT was the only STP method to significantly correlate with Herbage P and had a significant linear relationship with Herbage P in soil from Basalt regions (R² = 0.62). We found DGT to be a better predictor of the plant available P pool in soil in Northern Irish Dairy farms and recommend that DGT be incorporated into more extensive field trials and national/multi-national surveys.</div></div>","PeriodicalId":56001,"journal":{"name":"Geoderma Regional","volume":"43 ","pages":"Article e01027"},"PeriodicalIF":3.3,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145519729","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Leaching and ammonia emissions in rice fields exhibit greater influences by seasons than management","authors":"Nusrat Jahan Mumu ,&nbsp;Afsana Mimi Eiti Mony ,&nbsp;Md. Safinur Rahman ,&nbsp;Farjana Jannat Shimo ,&nbsp;Mouri Tania Joya ,&nbsp;Mrinmoyee Paul ,&nbsp;Noushin Tabassum ,&nbsp;Fawzia Fariha ,&nbsp;Mohammad Zaman ,&nbsp;Mohammad Mofizur Rahman Jahangir","doi":"10.1016/j.geodrs.2025.e01013","DOIUrl":"10.1016/j.geodrs.2025.e01013","url":null,"abstract":"<div><div>Estimation of ammonia (NH₃) emissions requires calculation of emission factors (EFs) based on experimental data that reflects seasonal and climatic variability, particularly in an annual triple cropping system. However, data on season-specific EFs under varying climate regimes are required to develop the management strategies that help mitigate nitrogen (N) loss via volatilization. A large portion of N releases into atmosphere from rice soils causing both economic and environmental costs since farmers indiscriminately use N fertilizers for rice production. Ammonia emissions and EFs were assessed in two different rice growing sites with an annual Boro–Aus–Aman sequence. Two sets of treatments were used: two residue treatments (no residue incorporation, NR; and 30 %, by height, crop residue incorporation, CR); and four N levels (control, CL; farmers' practice, FP; recommended nitrogen dose, RD; and 125 % of RD, 125RD). Crop residue incorporation significantly elevated NH₃ emissions. CR coupled with 125RD exhibited 10–27 %, 6–7 % and 6–9 % higher NH₃ emissions than NR-125RD in Boro, Aus and Aman seasons, respectively. Although the recommended N rate was higher in Boro, NH₃ emission was higher in Aman rice (28–34 kg NH₃-N ha⁻¹) suggesting that climatic conditions are the most influential driver rather than the N rate. Likewise, NH₃ EFs in RD ranged from 11 to 18 %, 16–33 % and 28–34 % in Boro, Aus and Aman seasons, respectively. Our results indicate that NH₃ emissions do not only depend on N rate but also on seasons where consideration of seasonal EFs is required to improve NH₃ and N budget. By contrast, N rate and crop residue did not influence N leaching but leaching was a considerable part of N loss from rice fields. Overall, our findings underscore the critical need for season-specific N fertilizer management including crop residue incorporation in multi-cropped rice systems to effectively mitigate NH₃ emissions while maintaining productivity.</div></div>","PeriodicalId":56001,"journal":{"name":"Geoderma Regional","volume":"43 ","pages":"Article e01013"},"PeriodicalIF":3.3,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145222458","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Arbuscular mycorrhizal fungal (AMF) diversity and population dynamics in organic vs Chemicalized fields concerning soil types, agroclimatic zones and different organic farming practices over seasons, in South India","authors":"Nirmal Philip George ,&nbsp;Joseph George Ray","doi":"10.1016/j.geodrs.2025.e00992","DOIUrl":"10.1016/j.geodrs.2025.e00992","url":null,"abstract":"<div><div>Arbuscular mycorrhizal fungi (AMF) are crucial plant root symbionts that enhance crop productivity, particularly in organic farming. They improve water and nutrient uptake, even in stressed environments, and can strengthen plant resistance. However, AMF effectiveness in agriculture depends on specific crops, agroclimatic conditions, physicochemical soil properties, agricultural practices, and soil types in cultivated fields. This study examined AMF diversity and population dynamics (based on spore count) in organically and conventionally managed fields cultivating five vegetable crops across diverse agroclimatic zones, soil nutrient contents, soil types, and diverse organic farming practices in Kerala, Karnataka, and Tamil Nadu states of South India. The aim was to determine how soil, other environmental, and plant factors influence AMF community dynamics (spore diversity and variations on specific spore counts) and activities (root colonization) in crop fields. The AMF identification relied on spore morphology. Results showed that irrespective of vegetable types, AMF diversity and activity (indirectly indicated by spore count and root colonization) in fields were significantly higher in organic fields, correlating with specific soil types. This extensive preliminary study enabled the identification of some general ecological relationships between AMF, soil, and agricultural practices, guiding future research into crop-soil-AMF interactions to explore AMF application as a biological tool for sustainable agriculture.</div></div>","PeriodicalId":56001,"journal":{"name":"Geoderma Regional","volume":"42 ","pages":"Article e00992"},"PeriodicalIF":3.3,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144772147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mineralogical controls over soil K reserves: A case study in Southeastern Brazil (Rio de Janeiro State)","authors":"Weslley Silva Julio ,&nbsp;Gabriel Ramatis Pugliese Andrade ,&nbsp;Josiane Leal Knupp ,&nbsp;Betânia Roqueto dos Reis ,&nbsp;Cláudio Roberto Marciano ,&nbsp;Antonio Carlos de Azevedo ,&nbsp;Valdomiro Severino Souza Junior","doi":"10.1016/j.geodrs.2025.e00980","DOIUrl":"10.1016/j.geodrs.2025.e00980","url":null,"abstract":"<div><div>Assessing soil potassium (K) reserves is essential to help developing strategies focused on reducing the dependence of tropical countries for K-fertilizers. Samples from six soils located at Southeastern Brazil (Rio de Janeiro State), were investigated to better understand the mineralogical control over their K reserves. Mineral assemblage was characterized through X-ray diffraction, using Rietveld Refinement to determine minerals contents in the coarse fractions and NEWMOD to describe and quantify interstratifications in clay fraction. Total (K_t) and non-exchangeable K (K_ne) were determined in the samples. The highest K_t and K_ne contents were observed in moderately-weathered Cambisol samples, with high primary mica contents in coarse fractions, as well as illite-rich interstratified phases in the clay fraction. Highly-weathered soils (Lixisols and a Histosol) rich in kaolinite, poorly-weathered soils (Phaeozem and Chernosol) rich in weatherable primary minerals (K-feldspars, plagioclases and amphiboles), and interstratified clays 2:1 clays presented low-to-moderate K_t and K_ne contents. There was a positive and significant correlation of K_t and K_ne contents with illite layers, mainly allocated at kaolinite-illite interstratifications. Multivariate statistical approach enabled assigning K_t, K_ne, primary micas and illite layers as combined variables accounting for differentiating Cambisol samples from other samples, which presented lower K reservoirs. The absence of correlations between muscovite and K_ne may be related to an underestimation of K_ne content by standard method (<em>Na</em>-tetraphenyl borate), likely due to its incapacity of extract K_ne efficiently from coarse particles. These findings emphasize illite-rich interstratified clays as major mineralogical controls over K reserves in the investigated tropical soils.</div></div>","PeriodicalId":56001,"journal":{"name":"Geoderma Regional","volume":"42 ","pages":"Article e00980"},"PeriodicalIF":3.1,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144307393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}