European Journal of Soil Science最新文献

{"title":"Cenozoic Time Constraints on the Evolution of a Gleysol‐Ferralsol‐Podzol Toposequence, Northwest Amazon Basin, Brazil","authors":"Célia Regina Montes, Thierry Allard, Madeleine Sélo, Yves Lucas, Chloé Fourdrin, Öykü Ataytür, Débora Ayumi Ishida, Etienne Balan, Adolpho José Melfi","doi":"10.1111/ejss.70327","DOIUrl":"https://doi.org/10.1111/ejss.70327","url":null,"abstract":"Deciphering the time milestones of clay formation is crucial for modeling the evolution of major geological systems near the Earth's surface. In the present study, kaolinite samples collected along four vertical profiles within a Gleysol‐Ferralsol‐Podzol soil toposequence near São Gabriel da Cachoeira, NW Amazon Basin (Brazil) are dated using electron paramagnetic resonance (EPR) spectroscopy. Owing to the large number of samples, only selected kaolinite samples were artificially irradiated and used as models for other samples sharing similar EPR spectra. The radiation dose rate was assessed using two contrasting models corresponding to a “linear” or “early” evolution of U, Th concentration during the profile formation. It was also assumed that Th is homogeneously distributed in the clay matrix. Both models reveal close and episodic histories of weathering based on average profile kaolinite ages. The average ages increase with elevation from Quaternary to Miocene and are discussed in terms of toposequence evolution and possible relation with formerly recognized paleoclimatic major episodes of kaolinite formation in the Amazon Basin. Discrete weathering episodes at 1–3 and 6–12 Ma are identified, aligning with known climatic and tectonic events in the Amazon Basin, such as the onset of monsoonal climate patterns and Andean uplift phases. Kaolinite from the podzol horizon of the top hill profile (P1) likely occurs due to inheritance and relative dissolution of the most disordered small grains rather than in situ formation while underlying kaolinic horizons display the oldest ages of the toposequence. Kaolinite samples in deep horizons from the bottom profile (P4) are the youngest and contain vanadyl (VO <jats:sup>2+</jats:sup> ) impurities, suggesting reducing conditions, which indicates in situ formation. Translocation from the upslope soils could have affected the topsoil of the P4 profile. Kaolinite ages in the intermediate profiles (P2 and P3) could result from a mixture of older and more recent populations. It is thus inferred that the soil sequence exhibits a dissolution/loss regime at the top and a formation regime on the slope and at the bottom. The study underscores the importance of considering specific environmental and geochemical contexts in interpreting EPR dating results in tropical soils.","PeriodicalId":12043,"journal":{"name":"European Journal of Soil Science","volume":"27 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2026-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147752658","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":"Pedodiversity‐Based Covariates for Digital Soil Mapping Framework","authors":"Radim Vašát, Oldřich Vacek, Luboš Borůvka, Vít Šrámek","doi":"10.1111/ejss.70334","DOIUrl":"https://doi.org/10.1111/ejss.70334","url":null,"abstract":"The integration of soil diversity as a covariate in digital soil mapping framework remains largely unexploited. However, we believe that it may carry important information that can be used to create more accurate digital maps of soil properties. Therefore, novel covariates are proposed based on the traditional concept of pedodiversity, which considers the number and abundance of individual soil classes, but exploited using the moving window (MW) method (an algorithm that proceeds incrementally and calculates statistics from individuals falling within a defined window). By moving a circular MW of a defined radius cell by cell across a rasterized (with a resolution of 50 m) Soil map of the Czech Republic (at a scale of 1:250,000), a diversity status value (Shannon's entropy) could be assigned to each raster cell. Furthermore, by varying the radius (4, 7, 10 and 15.2 km) of the MW, four different pedodiversity spatial patterns (PSP) were obtained. Subsequently, the PSPs were used together with other common covariates, such as morphometric terrain parameters (MTP) and climate, as covariates in the prediction of soil organic carbon (SOC) content (%) (depth 0–30 cm) for the forested land of the Czech Republic. To test the effect of the new covariates, several random forest models were calibrated (and validated) either using only the MTP and climate covariates or adding one of the PSPs (calculated with different MW radii). Furthermore, the difference between using the Soil map of the Czech Republic as a categorical covariate compared to PSP as numerical (continuous) one was assessed. As a result, the use of PSP led to a significant improvement in prediction accuracy, especially for PSP with the largest MW radius (15.2 km). The improvement was seen from 1.74 to 1.71 and from 0.46 to 0.49 in terms of RMSE and RSQ, respectively. PSP was shown to play an important role in improving model accuracy, as it (with a MW radius of 15.2 km) appeared among the top five covariates in terms of variable importance (generated with recursive feature elimination). Moreover, PSP as a numerical (continuous) covariate turns out to be more important than the polygon map of soil classes as a categorical one (the latter brought only a non‐significant improvement in prediction accuracy). The benefit of using PSP as a covariate was attributed to the existing relationship between soil classes and SOC content, while there is also a relationship between these soil units and the degree of pedodiversity.","PeriodicalId":12043,"journal":{"name":"European Journal of Soil Science","volume":"7 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2026-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147752655","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 Salts Affect MAOC Content and the Adsorption of Organic Matter on Clay Minerals in Coastal Saline Soils","authors":"Liwen Xu, Zhaojun Yang, Yingying Wang, Chengliang Li, Yanli Liu","doi":"10.1111/ejss.70338","DOIUrl":"https://doi.org/10.1111/ejss.70338","url":null,"abstract":"The composition of dissolved salts is a key factor controlling the formation of mineral‐associated organic carbon (MAOC) in coastal saline soils, but how salt type and concentration quantitatively affect the adsorption of organic matter to clay minerals remains unclear. In this study, a field experiment was conducted to investigate the effect of long‐term organic amendment on the MAOC of coastal saline soil and the correlation between MAOC and clay minerals. In addition, laboratory experiments were conducted to examine the adsorption–desorption behaviors of potassium humate (KH), glycine (G), and chitosan (CTS) on Na‐ and Ca‐saturated montmorillonite (Na‐M and Ca‐M, respectively), illite, and kaolinite in electrolytes with varying cationic and anionic compositions. The results of the field experiment showed a significant positive correlation between MAOC and clay mineral content. The adsorption data of KH and G by clay minerals were well fitted by the Langmuir model, suggesting a monolayer chemical adsorption mechanism. Among the tested clay minerals, Ca‐M exhibited the highest Langmuir‐derived maximum adsorption capacities (Q <jats:sub>m</jats:sub> ) for KH and G, with values of 571 and 631 mg g <jats:sup>−1</jats:sup> , respectively, and the measured desorption rates ranged from 8.6% to 20%. In contrast, Na‐M showed the highest Q <jats:sub>m</jats:sub> for CTS (432 mg g <jats:sup>−1</jats:sup> ) among all clay minerals. The adsorptions of KH and G were 53–318% higher in Ca <jats:sup>2+</jats:sup> and Al <jats:sup>3+</jats:sup> electrolytes than in Na <jats:sup>+</jats:sup> systems. Increasing Na <jats:sup>+</jats:sup> concentration gradually from 0.01 to 0.05 M in electrolyte enhanced KH adsorption by 29%–72% but reduced CTS adsorption by 6.8%–15% on the Na‐saturated clays, while it decreased KH adsorption by 1.3%–11% yet increased G adsorption by 8.3–20% on the Ca‐saturated clays. G adsorption was significantly correlated with the cation exchange capacity (CEC) ( <jats:italic>r</jats:italic> = 0.81) and specific surface area (SSA) ( <jats:italic>r</jats:italic> = 0.87) of the clay minerals. With the adsorption of KH, the SSAs and CECs of clay minerals increased by 5.1%–42% and 4.5%–96%, respectively. CTS adsorption increased the interlayer spacings of Na‐M and Ca‐M. Saturation by Ca <jats:sup>2+</jats:sup> and Na <jats:sup>+</jats:sup> changed the adsorption capacities of the clay minerals for organic matter in different electrolytes. This study demonstrated that compared to monovalent cations, the presence of bivalent or multivalent cations is more favorable for the formation of organo‐mineral complex in coastal saline soils. Therefore, it is suggested that Ca‐based mineral conditioner be applied together with organic material to better improve SOC in coastal saline soils.","PeriodicalId":12043,"journal":{"name":"European Journal of Soil Science","volume":"3 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2026-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147752657","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":"Distinguishing Soil Horizons of Alfisols Using MIR , Vis– NIR , and XRF Spectra","authors":"Gafur Gozukara, Alfred E. Hartemink, Eric O. Young, Yakun Zhang","doi":"10.1111/ejss.70337","DOIUrl":"https://doi.org/10.1111/ejss.70337","url":null,"abstract":"We studied horizonation of 150 Alfisols on a research farm in Wisconsin, USA. Most of these Alfisols had developed in loess covering dense glacial till; common horizons were an Ap over a glossic horizon (E/Bt or Bt/E) over a Bt covering the glacial till (2Bt). In addition to field identification, we distinguished the horizons by combining soil properties and spectra (Vis–NIR, MIR, and XRF) using a random forest (RF) model. A total of 503 soil samples from 150 pedons were analyzed. Soil samples were scanned using visible–near infrared (Vis–NIR) (350–2500 nm), mid‐infrared (MIR) (4000–600 cm <jats:sup>−1</jats:sup> ), and X‐ray fluorescence (XRF) (0–50 keV) spectrometers. Higher silt, pH, soil organic carbon (SOC), Ca, K, P, Si, Ti, Zn, and Zr contents were measured in the Ap horizon, whereas the glossic horizons were characterized by higher CIE <jats:italic>L * (lightness)</jats:italic> and <jats:italic>b</jats:italic> * (yellow‐blue) values. The underlying Bt horizon had higher clay, Al, and Fe contents, while the 2B(t) horizon was distinguished by higher sand, coarse fragments, and CIE <jats:italic>a</jats:italic> * values. The combination of soil properties and spectra (Vis–NIR, MIR, XRF) achieved a higher overall accuracy for predicting soil horizons compared to their individual use. The Ap horizons were best predicted using MIR or XRF (R <jats:sup>2</jats:sup> = 0.98), the glossic horizons using combined Vis–NIR and XRF spectra (R <jats:sup>2</jats:sup> = 0.98), the Bt horizons using MIR (R <jats:sup>2</jats:sup> = 0.90), whereas the 2B(t) horizons were best predicted using combined spectra (Vis–NIR + MIR + XRF) (R <jats:sup>2</jats:sup> = 0.50). In the absence of soil data, these spectra can be used with high accuracy to distinguish A and various B horizons of Alfisols.","PeriodicalId":12043,"journal":{"name":"European Journal of Soil Science","volume":"22 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2026-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147752656","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":"Root or Shoot: Tracing the Pathways of Soil Organic Carbon Accumulation Through Plant‐Specific Contributions","authors":"Anouk Lyver, Jean‐Bernard Cliquet, Emmanuelle Travaille, Fanny Leroy, Isabelle Trinsoutrot‐Gattin, Murilo Veloso","doi":"10.1111/ejss.70324","DOIUrl":"https://doi.org/10.1111/ejss.70324","url":null,"abstract":"Soil organic carbon (SOC) in agricultural soils is a cornerstone of soil health and climate change mitigation, and its accumulation is largely dependent on composition and addition rates of plant residues. Our objectives were to determine the stabilization pathways of SOC derived from root and shoot residues of different plant species and to assess the impact of shoot input rates on these pathways. We cultivated in pots three species selected for their different C:N ratios—wheat ( <jats:italic>Tricitum aestivum</jats:italic> ), crimson clover ( <jats:styled-content style=\"fixed-case\"> <jats:italic>Trifolium incarnatum</jats:italic> </jats:styled-content> ) and pea ( <jats:styled-content style=\"fixed-case\"> <jats:italic>Pisum sativum</jats:italic> </jats:styled-content> ) – and exposed to weekly <jats:sup>13</jats:sup> CO <jats:sub>2</jats:sub> pulse labeling until the flowering stage. At harvest, shoot and root were collected for biochemical and morphological characterization, and <jats:sup>13</jats:sup> C tracing in soil was used to estimate rhizodeposition‐derived C. To assess the contributions of root and shoot degradation to SOC, pots containing soil and intact root systems, and soil amended with different shoot residues rates (1, 2, or 6 Mg C ha <jats:sup>−1</jats:sup> ) were incubated under controlled conditions for 2 and 12 months. Soils incubated with shoot and root residues were particle size fractionated into particulate organic matter (POM), and mineral‐associated organic matter (MAOM) consisting of fine silt and clay fractions. A greater amount of SOC was derived from rhizodeposition and root degradation by wheat (0.58 and 0.70 g kg <jats:sup>−1</jats:sup> , respectively) than legumes (0.22 and 0.001 g kg <jats:sup>−1</jats:sup> , respectively). On the other hand, a greater contribution of legume‐ than wheat‐ shoot residues was observed to SOC (0.71 vs. 0.29 g kg <jats:sup>−1</jats:sup> ) and to clay‐C fraction (0.90 vs. 0.63 g kg <jats:sup>−1</jats:sup> ), particularly at 2 and 6 Mg C ha <jats:sup>−1</jats:sup> . The high content of recalcitrant compounds such as hemicellulose and cellulose of wheat roots explains the strong contribution to SOC and their preferential accumulation in POM. Conversely, the preferential contribution of legume shoots to MAOM is likely due to the higher water‐soluble compounds and N contents. Our results suggest that both grasses and legumes can enhance SOC content by targeting different organic matter pools. Similar studies conducted in the field could contribute to emphasize the role of plant‐specific residue composition in shaping C stabilization pathways in the soil.","PeriodicalId":12043,"journal":{"name":"European Journal of Soil Science","volume":"152 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2026-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147752659","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":"Composite Soil Samples Reflect the Arithmetic Mean pH of the Individual Cores","authors":"Mark Conyers","doi":"10.1111/ejss.70329","DOIUrl":"https://doi.org/10.1111/ejss.70329","url":null,"abstract":"The pH of composite soil samples has been reported to be well approximated by the arithmetic mean pH of the individual soil cores, rather than the arithmetic mean of (H <jats:sup>+</jats:sup> ) back transformed to pH. The calculations provided here show that this is due to the mixing of negatively charged soil colloids rather than the mixing of unbuffered solutions extracted from the soil by electrolytes such as 0.01 M CaCl <jats:sub>2</jats:sub> . Therefore, the conversion of pH to (H <jats:sup>+</jats:sup> ), averaging, and then back transform to pH is an unnecessary process when estimating the pH of combined soil samples and the use of the arithmetic mean is recommended.","PeriodicalId":12043,"journal":{"name":"European Journal of Soil Science","volume":"19 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2026-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147725593","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":"Phosphogypsum Doses and Subsoil Contamination: A Study on the Mobility of Rare Earth Elements, Uranium, and Thorium","authors":"Luís Paulo P. Tanure, Isabela C. F. Vasques, Renato W. Veloso, Maria Maiara C. Tanure, Walter A. P. Abrahão, Carlos Roberto Bellato, Massimo Gasparon, Jaime W. V. de Mello","doi":"10.1111/ejss.70325","DOIUrl":"https://doi.org/10.1111/ejss.70325","url":null,"abstract":"Soil conditioners are commonly used by producers aiming to enhance agricultural productivity, and among these products, phosphogypsum has gained increasing attention. As an agricultural amendment, phosphogypsum contains rare earth elements (REE), uranium (U), and thorium (Th), raising environmental concerns regarding its long‐term use. This study evaluated the vertical distribution of REE, U, and Th in the soil profile of an Oxisol under increasing phosphogypsum application rates. The experimental design included plots with four replicates, with phosphogypsum applied in 2003 in a single operation along the planting row. Application rates were 0 (control), 9.4, 16, and 24 t ha <jats:sup>−1</jats:sup> . Soil samples were collected from seven depth intervals (0–5, 5–10, 10–20, 20–40, 40–60, 60–100, and 100–200 cm). Following acid digestion, element concentrations were determined using ICP‐MS. The results revealed a significant effect ( <jats:italic>p</jats:italic> &lt; 0.01) of phosphogypsum application on the mobility and redistribution of elements throughout the soil profile. The input of REE, U, and Th from phosphogypsum in soils can reach 3.62 g kg <jats:sup>−1</jats:sup> and is mainly composed of light rare earth elements (LREE). Elevated contents of REE, U, and Th were observed, particularly in the uppermost layer. Despite considerable losses of most elements relative to the total applied, elements such as cerium, scandium, uranium, and thorium exhibited notable enrichment at various depths, especially at the surface. The application of high phosphogypsum doses can alter the vertical distribution of REE, U, and Th, potentially promoting their downward migration beyond 200 cm, which raises concerns about soil contamination with radionuclides and the risk of groundwater contamination. Background values of REE, U and Th must be stated in order to evaluate the anthropogenic contamination due to phosphogypsum application.","PeriodicalId":12043,"journal":{"name":"European Journal of Soil Science","volume":"324 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2026-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147725594","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":"Organic Carbon and Texture Control Moisture Dependence of Soil Shortwave Infrared Reflectance","authors":"D. Hick, P. J. Chapman, T. S. Breure, G. Ziv","doi":"10.1111/ejss.70319","DOIUrl":"https://doi.org/10.1111/ejss.70319","url":null,"abstract":"Moisture content affects soil reflectance in the optical domain (400–2500 nm), acting as a confounding factor in soil property prediction models. Soil reflectance needs to be simulated efficiently for varying levels of soil moisture, in order to aid soil property prediction efforts and inform physical land surface models. Here, we built on previous work that investigated how soil reflectance decreases with increasing soil moisture. We explored how the relationship between the reflectance and soil moisture content changes as a function of wavelength and soil characteristics. For this purpose, we acquired the spectra of 28 soil samples from various locations across Europe in a laboratory setting, at different levels of soil moisture. The soil reflectance‐moisture relationship was found to be wavelength‐dependent and best represented by decreasing exponential functions. The rates of exponential decrease, however, varied across soil samples and were normalised to isolate effects of different soil characteristics. It was found that organic carbon (OC), clay and silt content displayed a statistically significant relationship with the normalisation factor, a proxy for how quickly soil ‘darkens’ with increasing soil moisture content. A multiple linear regression model was used to describe the normalisation factor based on OC content and soil textural information. The resulting model was able to explain 67% of the variance, with OC and clay content accounting for almost 70% of the relative feature importance. Our findings call for the inclusion of OC content and textural information, especially clay content, in physical models of soil moisture‐reflectance, for more efficient simulations of soil reflectance at varying levels of soil moisture, to support climate models and soil property predictions efforts based on field and remotely sensed data.","PeriodicalId":12043,"journal":{"name":"European Journal of Soil Science","volume":"19 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2026-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147720037","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":"Depth and Tillage Dependent Stoichiometry of C, N, S, and H in Ukrainian Mollisol","authors":"Yuriy Kravchenko","doi":"10.1111/ejss.70335","DOIUrl":"https://doi.org/10.1111/ejss.70335","url":null,"abstract":"Tillage profoundly alters the vertical organization and coupling of biophilic elements in soils, yet depth‐resolved responses of carbon (C), nitrogen (N), sulfur (S), and their stoichiometric relationships remain poorly constrained in Mollisols. This study quantified the long‐term effects of conventional tillage (CTu), deep minimum tillage (DRTu), and shallow minimum tillage (RTu) on the distribution of total carbon (TC), organic carbon (SOC), inorganic carbon (SIC), organic nitrogen (SON), organic sulfur (SOS), organic hydrogen (SOH) in soil, and their stoichiometric ratios across a 0–100 cm profile of a Ukrainian Mollisol. Elemental composition was determined by CHNS‐O elemental analysis following carbonate removal, and stoichiometric ratios were evaluated on a molar basis. Conventional tillage homogenized SOC and SON within the plow layer (0–30 cm) but resulted in the widest molar C:N, C:S, and C:H ratios. This stoichiometric expansion signifies a functional shift in SOM architecture: the preferential mineralization of labile, heteroatom‐rich organic fractions and the subsequent dominance of element‐depleted, chemically processed residues stabilized as mineral‐associated organic matter (MAOM). Conversely, shallow minimum tillage promoted strong vertical stratification (0–5 cm), maintaining the narrowest stoichiometric ratios. These narrow ratios, coupled with significantly higher SOH content, indicate the preservation of “molecularly fresh” plant‐derived and microbially processed organic matter, characterized by high functional group density and aliphatic structures that are otherwise lost under intensive inversion. Deep minimum tillage exhibited a hybrid response, combining surface accumulation with enhanced retention of SOC, SON, SOS, and SOH in the 20–40 cm layer and pronounced narrowing of C:S and N:S ratios in deeper horizons (&gt; 60 cm), indicative of effective co‐stabilization of carbon and sulfur at depth. Across all tillage systems, increasing depth was associated with convergence toward narrower C:N:S ratios, reflecting progressive microbial processing and increasing mineral association of organic matter. Our results demonstrate that tillage intensity acts as a selective pressure, shifting the Mollisol profile from a biophilic, element‐rich state under conservation management to a more recalcitrant, element‐depleted state under intensive inversion.","PeriodicalId":12043,"journal":{"name":"European Journal of Soil Science","volume":"22 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2026-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147720067","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":"Inorganic Carbon (Calcite and Dolomite) Determination Using the Modified Pressure‐Calcimeter Method","authors":"Xucheng Hu, Franklin S. Jones, James A. Ippolito","doi":"10.1111/ejss.70332","DOIUrl":"https://doi.org/10.1111/ejss.70332","url":null,"abstract":"Soil inorganic carbon (SIC) quantification is critical for accurately determining soil organic carbon (SOC) in carbonate‐containing soils when SOC is determined as the difference between total C and SIC. Generally, the pressure‐calcimeter method (described by Sherrod et al.) is used to quantify SIC content using a relatively simple approach, with the method broadly used in laboratories globally to quantify SIC. The original study suggested using a 6 h incubation time based only on calcite (CaCO <jats:sub>3</jats:sub> ); dolomite (CaMg(CO <jats:sub>3</jats:sub> ) <jats:sub>2</jats:sub> )‐containing soils were neglected. Additionally, most laboratories adopting the pressure‐calcimeter method for SIC measurements shorten the incubation duration to 2 h to facilitate analytical efficiency. This study evaluated the optimal incubation time (from 2 to 48 h) for calcite and/or dolomite‐containing soils using the pressure‐calcimeter method as compared to the Chittick apparatus. Results identified 6 h as the optimal reaction time for maximum CO <jats:sub>2</jats:sub> release from dolomitic soils. Among 18 soils containing varying concentrations of calcite and dolomite, the pressure‐calcimeter and Chittick apparatus methods were strongly correlated ( <jats:italic>R</jats:italic> <jats:sup>2</jats:sup> = 0.98), supporting the accuracy of the pressure‐calcimeter method in quantifying total SIC content. Compared to traditional methods, the pressure‐calcimeter method offers enhanced safety, efficiency, and scalability for large‐scale soil analysis globally, and will capture all SIC within a 6‐h timeframe.","PeriodicalId":12043,"journal":{"name":"European Journal of Soil Science","volume":"96 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2026-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147695722","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}