Geoderma最新文献

{"title":"Mechanisms of generation and accumulation of geogenic Cr(VI) in serpentinite-weathered soils","authors":"Rouyun Zhou ,&nbsp;Bolang Luo ,&nbsp;Ming Ao ,&nbsp;Taicong Liu ,&nbsp;Ruichun Meng ,&nbsp;Loua-Augustin Bonaventure ,&nbsp;Xiaoli Qian ,&nbsp;Jean-Louis Morel ,&nbsp;Pan Wu ,&nbsp;Shizhong Wang ,&nbsp;Rongliang Qiu","doi":"10.1016/j.geoderma.2026.117675","DOIUrl":"10.1016/j.geoderma.2026.117675","url":null,"abstract":"<div><div>Natural oxidation of geogenic Cr(III) to carcinogenic Cr(VI) is a major source of Cr contamination in soil and water. However, the mechanisms of Cr(VI) generation and occurrence under anoxic conditions remain unclear. Although Mn(III/IV) oxides are considered key oxidants, their interactions with stable Cr(III) minerals and the subsequent fate of Cr(VI) represent critical knowledge gaps. This study combines field profile analysis of serpentinite weathering in southwest China with laboratory experiments to clarify these processes. We introduce a new mechanism termed “in situ oxidation-surface adsorption” mechanism: the stability of secondary Cr(III) minerals governs oxidation sensitivity, Mn(III/IV) oxides drive Cr(VI) generation via direct surface contact, while Fe(III)/Mn(III/IV) oxides act as effective adsorbents retaining Cr(VI) in the solid-phase. Experimental results indicate that sub-stable Cr(OH)₃ formed during serpentinite weathering is the primary contributor to Cr(VI) generation, while Cr₂O₃ is negligible. In conditions with low reductants, more than 99.8% of the Cr(VI) generated is adsorbed onto the surfaces of Fe(III)/Mn(III/IV) oxides, creating a stable “Cr(VI) reservoir” with limited release into the aqueous phase. These findings challenge conventional dissolution-migration-oxidation models and enhance our understanding of Cr(VI) generation and accumulation in anoxic soils, providing crucial insights for assessing and managing geological Cr risks.</div></div>","PeriodicalId":12511,"journal":{"name":"Geoderma","volume":"466 ","pages":"Article 117675"},"PeriodicalIF":6.6,"publicationDate":"2026-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145956995","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"How strongly do management practices and scales influence soil erosion rates in olive orchards? Empirical evidence from Alentejo (Portugal)","authors":"V. Daimonakos ,&nbsp;A.Van Zinderen ,&nbsp;J. Muñoz-Rojas ,&nbsp;D. Costa ,&nbsp;J.P. Nunes ,&nbsp;S.A. Prats","doi":"10.1016/j.geoderma.2026.117673","DOIUrl":"10.1016/j.geoderma.2026.117673","url":null,"abstract":"<div><div>The use of vegetation suppression, such as herbicide application and mechanical plowing in olive orchards can exacerbate soil erosion. Maintaining understory vegetation can mitigate erosion and enhance soil fertility. Although prior research has assessed the soil management impact on erosion, knowledge gaps persist regarding dominant erosion processes across spatial scales and management effects on soil microenvironments (tree canopy, wheel ruts, vegetation strips). This study systematically evaluates how soil management (herbicides, plowing, no intervention) and spatial scales (microplots, hillslope plots) affect erosion dynamics, soil properties and their interactions with rainfall, ground cover, and orchard characteristics in Alentejo, Portugal. Over two years, seven orchards with varying management practices were monitored for erosion rates, ground cover, and soil properties. Soil management strongly influenced erosion, with herbicides inducing the highest hillslope-scale erosion (average 11.3 t ha⁻¹ yr⁻¹) and plowing dominating microplot erosion, while untreated plots exhibited minimal erosion (up to 99 % lower than the herbicide treatments). Wheel rut areas increased hillslope erosion through runoff concentration and bare soil, while vegetation strips suppressed it completely. Tree canopy areas varied: plowing mobilized new sediments, whereas untreated/herbicide microplots showed no erosion due to vegetation cover or stone‑lag armoring. Hillslope erosion stemmed from cumulative runoff, while microplots were influenced by soil properties like roughness or bulk density. Our findings highlight the need to consider scale effects in erosion modelling and policy. Future research should explore longer-term trends, expand underlying conditions (e.g. soil types, climatic zones or management practices), and refine soil erosion models to support sustainable soil conservation.</div></div>","PeriodicalId":12511,"journal":{"name":"Geoderma","volume":"466 ","pages":"Article 117673"},"PeriodicalIF":6.6,"publicationDate":"2026-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145915418","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Absorptive roots outweigh transport roots in modulating nitrogen-addition effects on soil organic carbon accumulation in a subtropical forest","authors":"Yuanshuang Yuan ,&nbsp;Xianwang Du ,&nbsp;Yicong Yin ,&nbsp;Bartosz Adamczyk ,&nbsp;Ziliang Zhang","doi":"10.1016/j.geoderma.2025.117571","DOIUrl":"10.1016/j.geoderma.2025.117571","url":null,"abstract":"<div><div>Root carbon (C) inputs play a pivotal role in mediating the formation, accumulation, and turnover of soil organic C (SOC). However, how different root functional modules (absorptive roots [ARs] vs. transport roots [TRs]) regulate SOC dynamics under elevated atmospheric nitrogen (N) deposition remains unclear. By separately collecting rhizosphere soils of ARs and TRs and quantifying SOC accumulation therein, we characterized the distinct roles of these two root modules in regulating SOC dynamics in a subtropical karst forest subjected to different rates of N additions. Nitrogen addition promoted SOC accumulation in the rhizosphere of both ARs and TRs, especially at higher N-addition rate. Moreover, the rhizosphere SOC contents of ARs were significantly higher than those of TRs across N-addition treatments. Correlation analysis indicated that under the influence of ARs, SOC content was significantly and positively correlated with both protective mineral-associated SOC poos and microbial carbon pump (MCP) efficacy. By contrast, in the context of TRs, a significantly positive association was observed exclusively between SOC content and protective mineral pools, with no significant correlation of SOC content with MCP efficacy. These findings suggest that ARs outweigh TRs in mediating the effects of N addition on SOC accumulation. Mechanisms driving N-induced SOC accumulation may differ between two root functional modules, with each module governing distinct regulatory pathways. This study highlights the necessity to integrate root functional traits, particularly those distinguishing ARs and TRs, into process-based predictive frameworks of ecosystem C cycling. Such integration is critical for improving the mechanistic understanding and predictive accuracy of soil C dynamics in the context of projected N deposition regimes.</div></div>","PeriodicalId":12511,"journal":{"name":"Geoderma","volume":"465 ","pages":"Article 117571"},"PeriodicalIF":6.6,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145823031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mineral-associated organic nitrogen pool size, composition, and accessibility mediated by agricultural management and soil geochemical characteristics","authors":"Gabriella M. Griffen ,&nbsp;Andrew H. Whitaker ,&nbsp;Emma L. Bergh ,&nbsp;Marian Carrell ,&nbsp;Erik Knatvold ,&nbsp;Aniko Konya ,&nbsp;A. Stuart Grandy ,&nbsp;Andrea Jilling ,&nbsp;Marco Keiluweit ,&nbsp;Rachel Hestrin","doi":"10.1016/j.geoderma.2025.117627","DOIUrl":"10.1016/j.geoderma.2025.117627","url":null,"abstract":"<div><div>Mineral-associated organic matter (MAOM) contains a substantial portion of soil nitrogen (N). MAOM-N could serve as an important N source for crops, but its availability and response to agricultural management across different soil types remains largely unknown. We characterized MAOM-N isolated from nine paired soils spanning a range of geochemical characteristics and maintained under two land uses—more intensively managed annual cropping systems or less intensively managed grasslands. On average, we found that MAOM contained approximately two-thirds of total soil N. Across all soil types, more intensive agricultural management resulted in a 50% decline in MAOM-N stocks, as well as a reduction in MAOM-N molecular diversity. Although clay content and extractable metals were positively correlated with MAOM-N stocks, none of the geochemical characteristics measured were strongly predictive of MAOM-N decline due to land use. This suggests that more intensive crop management limited the formation or caused the disruption of a broad suite of associations between a variety of soil minerals and organic N compounds. Under both agricultural land uses, approximately 20% of MAOM-N was mobilized through sequential extractions that may mimic conditions in the rhizosphere, suggesting that a significant portion of MAOM-N may be available to plants. Together, these findings help to quantify MAOM’s potential to supply crops with N across different soil types and agricultural systems. This can inform agricultural management recommendations and supports a growing understanding of MAOM as a dynamic N source and sink.</div></div>","PeriodicalId":12511,"journal":{"name":"Geoderma","volume":"465 ","pages":"Article 117627"},"PeriodicalIF":6.6,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145902302","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Global patterns and drivers of decomposition of mixed-species litter","authors":"Limin Bai ,&nbsp;Chao Song ,&nbsp;Mengfan Li ,&nbsp;Lei Yang ,&nbsp;Xin Wang ,&nbsp;Qiqian Wu ,&nbsp;Jianxiao Zhu","doi":"10.1016/j.geoderma.2025.117662","DOIUrl":"10.1016/j.geoderma.2025.117662","url":null,"abstract":"<div><div>Mixed-species litter modifies decomposition rates through complex interplays driven by species composition and functional traits of litter. However, there remains no consensus on how ecosystem type, climate, species traits, and decomposition stage jointly influence the direction and magnitude of litter mixing effects. We conducted a global meta-analysis of 1,258 effect sizes from 91 field studies (1989–2024) to assess how ecosystem type, climate, and species traits influence mixed-species litter decomposition rates across different stages of decomposition. Decomposition rates of mixed-species litter were 4.4 % significantly higher than those of the mono-species litter. Synergistic effects were most pronounced in temperate and forest ecosystems. These effects were generally observed after 180 days, and peaked between 360 and 720 days, but they declined as decomposition progressed, often shifting to additive or antagonistic effects as recalcitrant compounds accumulated. The relationship between species diversity and mixing effects was not linear, depending on specific species combinations and proportions. Phylogenetic distance and litter quality divergence between species significantly affect the mixing effect of decomposition. The mixing effects of litter decomposition are highly context-dependent and temporally dynamic. Our results provide empirical support for a dynamic, stage-dependent theory of litter mixing effects, emphasizing that their strength and direction hinge on critical decomposition phases and trait-mediated interactions. Recognizing these temporal dynamics is essential for predicting biodiversity impacts on ecosystem carbon and nutrient cycling.</div></div>","PeriodicalId":12511,"journal":{"name":"Geoderma","volume":"465 ","pages":"Article 117662"},"PeriodicalIF":6.6,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145902315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Harvest intensity, rather than harvest method or soil preparation, affects post-harvest nutrient leaching in acidic sandy forest soils","authors":"Marleen A.E. Vos ,&nbsp;Wim de Vries ,&nbsp;Jorad de Vries ,&nbsp;Marcel R. Hoosbeek ,&nbsp;José A. Medina Vega ,&nbsp;Richard Sikkema ,&nbsp;Frank Sterck","doi":"10.1016/j.geoderma.2025.117657","DOIUrl":"10.1016/j.geoderma.2025.117657","url":null,"abstract":"<div><div>Increasing demands for timber and biomass production from European forests have raised concerns about the sustainability of harvesting practices, since forest nutrient stocks have decreased due to enhanced leaching of base cations driven by soil acidification from elevated nitrogen (N) and sulfur (S) deposition. We quantified the impact of three harvest intensities—high-thinning (also known as crown thinning; ∼20 % basal area removal), shelterwood (∼80 %), and clearcut (100 %)—, two harvest methods (stem-only and whole-tree harvest), and soil preparation (shallow mulching and no mulching) on post-harvest nutrient leaching in beech, Douglas fir, and Scots pine stands in the Netherlands, compared to unharvested control plots. Leaching was quantified by combining monthly dissolved nutrient measurements over a full year with a mechanistic model simulating monthly water fluxes.</div><div>Leaching of macronutrients in unharvested control plots was generally higher in Douglas fir than in Scots pine and beech. Clearcutting, and to a lesser extent shelterwood harvesting, strongly increased dissolved nutrient concentrations, especially nitrate (NO₃), indicating rapid mobilization of large N stocks and, to a lesser extent, S stocks. These increases were associated with accelerated soil acidification, induced by losses of base cations (calcium [Ca], magnesium [Mg] and potassium [K]) and acid cations (aluminum [Al], iron [Fe] and manganese [Mn]). Thinning, harvest method, and shallow mulching had minimal or negligible effects on post-harvest leaching, underscoring the potential of low-intensity harvests for sustainable forest use with low nutrient losses. Our study shows that high harvest intensity strongly accelerates nutrient leaching within one year after harvest, but the long-term impacts over a rotation period remain to be explored.</div></div>","PeriodicalId":12511,"journal":{"name":"Geoderma","volume":"465 ","pages":"Article 117657"},"PeriodicalIF":6.6,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145902303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Scale dependence of genome-derived microbial functional diversity informing soil functions","authors":"Nannan Wang ,&nbsp;Kexin Li ,&nbsp;Xinhao Zhu ,&nbsp;Yunjiang Zuo ,&nbsp;Jianzhao Liu ,&nbsp;Ziyu Guo ,&nbsp;Ying Sun ,&nbsp;Yuedong Guo ,&nbsp;Changchun Song ,&nbsp;Fenghui Yuan ,&nbsp;Xiaofeng Xu","doi":"10.1016/j.geoderma.2025.117659","DOIUrl":"10.1016/j.geoderma.2025.117659","url":null,"abstract":"<div><div>The relationship between soil multifunctionality and microbial diversity is well established, and using genomic data to link microbial diversity with soil functions is increasingly recognized as a reliable approach, despite challenges such as horizontal gene transfer, functional redundancy, and transcriptional uncertainty. Here, we investigated how microbial taxonomic and functional diversities derived from metagenomic data explain soil multifunctionality across soil profiles. We conducted analyses across four seasons and two contrasting hydrological habitats: wetland and cropland. We found that microbial functional diversity captured soil functions more effectively than taxonomic diversity, and its explanatory power depended on scale, strongest at broader classification levels (phylum/module) and higher data hierarchies (cosmopolitan). Microbial functional diversity explained 95 % and 79 % of individual soil functions in wetland and cropland, respectively, and showed a closer association with overall soil multifunctionality. The relationship remained consistent across spatial (0–100 cm soil profiles), temporal (four seasons), and hydrological (wetland and cropland) gradients, demonstrating greater stability than taxonomic diversity. By linking microbial diversity to soil functions across space and time, our findings show that genome-derived microbial functional diversity provides a robust and reliable framework for explaining soil functions, reinforcing the potential of genome-based microbial modeling.</div></div>","PeriodicalId":12511,"journal":{"name":"Geoderma","volume":"465 ","pages":"Article 117659"},"PeriodicalIF":6.6,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145902312","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spartina alterniflora invasion-induced soil organic carbon content changes: An assessment by time-series remote sensing and machine learning","authors":"Qingwen Zhang ,&nbsp;Dehua Mao ,&nbsp;Weidong Man ,&nbsp;Fuping Li ,&nbsp;Yongbin Zhang ,&nbsp;Fenghua Wu ,&nbsp;Caiyao Kou ,&nbsp;Rui Yang ,&nbsp;Jiannan He ,&nbsp;Xuan Yin ,&nbsp;Mingyue Liu","doi":"10.1016/j.geoderma.2025.117650","DOIUrl":"10.1016/j.geoderma.2025.117650","url":null,"abstract":"<div><div>Coastal wetlands play a vital role in carbon sequestration and climate change mitigation. However, the invasion of <em>Spartina alterniflora</em> (<em>S.alterniflora</em>) poses a significant threat to these ecosystems. In this study, we collected 114 soil samples from <em>S.alterniflora</em>-invaded coastal wetlands and acquired monthly remote sensing images throughout the sampling year. Time-series variables covering the entire growth stages of <em>S.alterniflora</em> were extracted from these images. The iterative Boruta algorithm was employed to identify sensitive variables, and machine learning algorithms (Random Forest, Boosted Regression Trees, and eXtreme Gradient Boosting) were used to predict soil organic carbon (SOC) content. A space-for-time substitution approach was then applied to assess the impact of <em>S.alterniflora</em> invasion age on SOC dynamics. The results show that the correlation between SOC content and remote sensing variables varied significantly across months, with June-derived variables exhibiting the highest average correlation. Independent validation further indicated that all machine learning models achieved R² values above 0.6, with the random forest model performing best (R² = 0.663, nRMSE = 0.157, RPD = 1.713). NDWI was identified as the most important predictor based on variable importance and SHAP analysis, followed by the vertical–vertical (VV) polarization and shortwave infrared (SWIR) band reflectance. Furthermore, spatial evidence revealed that SOC content increased with invasion age, peaking at a saturation point after 19 years. A slight decline was observed after 22 years, due to the greater distance from the coastline, which may have limited the exchange of water, salt, and nutrients. These findings provide spatially explicit insights into the long-term effects of biological invasion on soil carbon dynamics and establish a scientific basis for the sustainable management of coastal wetlands under invasion pressure.</div></div>","PeriodicalId":12511,"journal":{"name":"Geoderma","volume":"465 ","pages":"Article 117650"},"PeriodicalIF":6.6,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145921707","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cross-modal integration framework for soil organic matter estimation using proximal and satellite spectral data: Modeling optimization with particle size effects and spatial similarity","authors":"Mingchang Wang ,&nbsp;Xingnan Liu ,&nbsp;Yilin Bao ,&nbsp;Jialin Cai ,&nbsp;Liheng Liang ,&nbsp;Yiting Fan ,&nbsp;Hongchao Fan","doi":"10.1016/j.geoderma.2025.117671","DOIUrl":"10.1016/j.geoderma.2025.117671","url":null,"abstract":"<div><div>Remote sensing (RS) technology enables the rapid and accurate acquisition of soil organic matter (SOM) content, which is crucial for ensuring food security and promoting precision agriculture. Multispectral imagery is widely used for large-scale SOM mapping, but its limited spectral resolution substantially constrains estimation accuracy. While proximal hyperspectral data provide detailed spectral information, their point-based observations limit scalability across large regions. To overcome these limitations, a cross-modal modeling framework integrating proximal hyperspectral and satellite spectral data was proposed. Hyperspectral reconstruction technology was applied to enhance satellite spectral resolution and to extend proximal hyperspectral observations into spatially continuous imagery, achieving a balance between spectral accuracy and spatial continuity. To address SOM spatial heterogeneity, a spatial similarity-based random forest (SS-RF) local modeling strategy was introduced. Furthermore, the study systematically evaluated the impact of different soil particle size levels on spectral reflectance and SOM estimation accuracy. This study was conducted in a typical black soil region located in Northeast China. A multimodal dataset was constructed for SOM modeling, including in-situ and laboratory hyperspectral data with multiple particle size treatments, as well as satellite imagery from Zhuhai-1 and Sentinel-2A. The results indicated that the proposed cross-modal fusion and SS-RF framework demonstrated superior SOM estimation performance. The reconstructed hyperspectral imagery effectively integrated proximal and satellite spectral data, thereby preserving spectral integrity and enhancing their correlation with SOM. Among these, the reconstructed imagery based on finer particle sizes (100 mesh, ≤0.15 mm) exhibited the best performance (R² = 0.874, LCCC = 0.756, RMSE = 2.871 g·kg⁻¹, and RPIQ = 2.159), while the reconstruction using 50 mesh particles (≤0.35 mm) also achieved comparatively good accuracy (R² = 0.864). In contrast, the model constructed using field in-situ hyperspectral reconstructed imagery produced the lowest accuracy (R² = 0.730). The estimation accuracy based on the reconstructed imagery was significantly higher than that achieved using Sentinel-2A (R² = 0.712) and Zhuhai-1 (R² = 0.759). Compared to traditional global models, the proposed SS-RF local strategy improved accuracy, increasing R² by 7.64 %. This synergistic optimization approach, which combines spectral reconstruction, local modeling, and particle size standardization provides new insights and technical support for high-precision SOM estimation at the regional scale.</div></div>","PeriodicalId":12511,"journal":{"name":"Geoderma","volume":"465 ","pages":"Article 117671"},"PeriodicalIF":6.6,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145902304","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Composition and persistence of soil organic matter along eroding and depositional transects in buried vs. modern soil layers: A case of the Brady paleosol at Wauneta, Nebraska","authors":"Manisha Dolui ,&nbsp;Teneille Nel ,&nbsp;Laura M. Phillips ,&nbsp;Abbygail R. McMurtry ,&nbsp;Kimber Moreland ,&nbsp;Malak Tfaily ,&nbsp;Karis McFarlane ,&nbsp;Joseph A. Mason ,&nbsp;Erika Marin-Spiotta ,&nbsp;Marie-Anne de Graaff ,&nbsp;Teamrat Ghezzehei ,&nbsp;Asmeret Asefaw Berhe","doi":"10.1016/j.geoderma.2025.117660","DOIUrl":"10.1016/j.geoderma.2025.117660","url":null,"abstract":"<div><div>Paleosols form when soils are buried through deposition by aeolian, colluvial, alluvial or other processes. Burial of former topsoil isolates soil organic matter (SOM) from surface conditions, allowing carbon to accumulate and potentially remain stable for millennia. In this study, SOM composition, distribution, and persistence were analyzed in the Brady Soil of Nebraska, USA to compare SOM spatial variability in modern and buried soils, as well as the impact of erosional exposure on SOM stability. The Brady Soil, formed as a surface soil during the Pleistocene-Holocene transition and now a paleosol buried up to 6 m deep (or more) by loess deposition during the Holocene, was sampled along burial (up to 5.8 m depth) and erosional (up to 1.8 m depth) transects to compare SOM dynamics in different geomorphic settings. Fourier Transform Infrared Spectroscopy (FTIR) and Fourier Transform ion cyclotron resonance mass spectrometry (FTICR-MS) were used to analyze SOM composition, while <span><math><msup><mrow><mi>δ</mi></mrow><mrow><mn>13</mn></mrow></msup></math></span>C isotope analyses identified SOM sources and radiocarbon values were used to estimate turnover rates. Results confirmed a vegetation shift from C3 to C4 plants after Brady Soil formation, reflecting warming climatic conditions. Increasing SOM age and decreasing <span><math><msup><mrow><mi>δ</mi></mrow><mrow><mn>13</mn></mrow></msup></math></span>C and <span><math><msup><mrow><mi>δ</mi></mrow><mrow><mn>15</mn></mrow></msup></math></span>N values with depth indicated slowing of decomposition rate in buried soils. Higher pH in the Brady Soil suggested greater base cation content, supporting SOM stabilization through organo-mineral associations and aggregate formation. However, exposure of the Brady Soil due to surface erosion caused faster SOM turnover. This result suggested susceptibility of buried SOM to losses via decomposition upon erosional exposure, possibly accelerated by priming in response to modern SOM inputs. These findings highlight the potential loss of carbon stocks in buried soils under future climate change, as shifts in soil physicochemical properties may destabilize long-preserved SOM.</div></div>","PeriodicalId":12511,"journal":{"name":"Geoderma","volume":"465 ","pages":"Article 117660"},"PeriodicalIF":6.6,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145902313","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}