Geoderma最新文献

{"title":"Wheel traffic compaction intensified with orchard age while hydraulic responses were partially decoupled in the top 30 cm","authors":"Siyu Wang ,&nbsp;Wei Hu ,&nbsp;Heather Jenkins ,&nbsp;Dougal Stalker ,&nbsp;Craig Tregurtha ,&nbsp;Rogerio Cichota ,&nbsp;Henry Wai Chau ,&nbsp;Jim Moir ,&nbsp;Karin Müller ,&nbsp;Brendon Malcolm","doi":"10.1016/j.geoderma.2026.117725","DOIUrl":"10.1016/j.geoderma.2026.117725","url":null,"abstract":"<div><div>Soil compaction from frequent wheel traffic is a concern in orchards. The potential impacts of soil compaction, particularly over orchard age, on soil physical properties, remain unclear. This study aimed to investigate the impacts of wheel traffic on soil physical properties, both mechanical and hydraulic, at various depths (0–10, 10–20, and 20–30 cm) across different plantation ages in two commercial apple orchards located in Canterbury (3, 12, and 40 years) and Tasman (12, 17, and 28 years), New Zealand. Soil samples and field measurements were taken at three positions: tree rows, wheel tracks, and inter-track areas. Penetration resistance, a mechanical property, was measured in situ as an indicator of compaction, while hydraulic properties, including total porosity, macroporosity, available water capacity, saturated hydraulic conductivity, and relative field capacity were measured in the laboratory using intact soil cores to assess water- and aeration-related functions. Results showed that wheel traffic significantly increased soil compaction, reducing available water capacity and saturated hydraulic conductivity and impairing aeration. Notably, these declines were also observed beyond the visibly compacted wheel tracks, suggesting more widespread functional impairment across orchard soils. Older plantations generally exhibited higher penetration resistance, and significant interactions between plantation age and sampling position were observed for penetration resistance. However, older plantations did not necessarily exhibit worse hydraulic conditions (e.g., available water capacity, saturated hydraulic conductivity), and no interactions between plantation age and sampling position were detected for soil hydraulic properties. These findings suggest that while wheel traffic-induced compaction impaired soil hydraulic functions, compaction intensity and hydraulic responses became less consistent with increasing plantation age. This study highlights the importance and potential of mitigating soil compaction to improve soil physical properties and environmental sustainability through targeted management interventions. Future research should focus on understanding the broader impacts of soil compaction on soil functions (e.g., water and aeration storage and transport) and ecosystem services in orchards.</div></div>","PeriodicalId":12511,"journal":{"name":"Geoderma","volume":"467 ","pages":"Article 117725"},"PeriodicalIF":6.6,"publicationDate":"2026-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146160811","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":"Amorphous aluminum hydroxide and rice-husk biochar enhance new organic carbon stabilization via different mechanisms","authors":"Han Lyu ,&nbsp;Arisa Nishiki ,&nbsp;Ruohan Zhong ,&nbsp;Ryosuke Kusumi ,&nbsp;Mayuko Seki ,&nbsp;Soh Sugihara ,&nbsp;Randy A. Dahlgren ,&nbsp;Shinya Funakawa ,&nbsp;Tetsuhiro Watanabe","doi":"10.1016/j.geoderma.2026.117721","DOIUrl":"10.1016/j.geoderma.2026.117721","url":null,"abstract":"<div><div>Increasing soil organic carbon (SOC) levels is essential for sustainable agricultural productivity and climate change mitigation, particularly in alkaline soils with inherently low SOC. While amorphous Al hydroxide (Am-Al) significantly influences SOC stabilization in volcanic and humid-region soils, and biochar enhances SOC in temperate and tropical regions, their effectiveness and stabilization mechanisms in alkaline soils require further exploration. We conducted a 1-year incubation of low SOC alkaline soils (5.2 g kg⁻¹) amended with ¹³C-labeled maize residue (1 g kg⁻¹), with or without Am-Al or rice-husk biochar (each 10 g kg⁻¹); residue mineralization/retention was quantified and molecular composition profiled by solid-state ¹³C NMR and Py-GC/MS. Rapid decomposition of plant residue ceased around 12 weeks, while plant residue-derived C and native SOC decomposition continued throughout the incubation period. Am-Al significantly reduced maize mineralization within the initial two weeks and retained a higher proportion of residue-derived C than the control soil with maize addition after one year (Am-Al: 36% vs. Control: 28%). ¹³C NMR and pyrolysis–GC/MS showed smaller decreases in carbohydrate-C and saccharides and a higher carbon preference index and odd–even predominance of alkanes, indicating that Am-Al better preserved carbohydrate- and cuticular-wax-derived components, proxies for less-degraded residues. Respiration dynamics and molecular fingerprints indicate Am-Al rapidly stabilizes labile plant compounds, possibly through non-electrostatic sorption and ligand-exchange. Biochar also retained more residue-derived C (33%) than the control, but its effects on mineralization emerged later in the incubation (&gt;6 months). We attribute this lag to surface degradation/activation of the biochar, which may stabilize residue-derived C more efficiently. Overall, adding Am-Al or biochar with plant residues significantly increased residue-derived C retention through immediate and delayed mechanisms, respectively. Treatments combining Am-Al or biochar with plant residue yielded a net positive C balance over the incubation, whereas residue alone was negative. Thus, the application of Am-Al and biochar with plant residues represents a promising strategy for sustained C stabilization, thereby improving SOC in degraded alkaline soils.</div></div>","PeriodicalId":12511,"journal":{"name":"Geoderma","volume":"467 ","pages":"Article 117721"},"PeriodicalIF":6.6,"publicationDate":"2026-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146172867","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":"Spectroscopic analysis shows crandallite can be a major component of soil phosphorus","authors":"Christian Vogel ,&nbsp;Julian Helfenstein ,&nbsp;Michael Massey ,&nbsp;Ruben Kretzschmar ,&nbsp;Ulrich Schade ,&nbsp;René Verel ,&nbsp;Oliver Chadwick ,&nbsp;Emmanuel Frossard","doi":"10.1016/j.geoderma.2026.117712","DOIUrl":"10.1016/j.geoderma.2026.117712","url":null,"abstract":"<div><div>Phosphorus (P) bioavailability is crucial for the productivity of natural and agricultural ecosystems, and soil P speciation plays a major role therein. Better understanding of P forms present in soil is thus essential to predict bioavailability. However, P speciation studies are only as powerful as the reference spectra used to interpret them, and most studies rely on a limited set of reference spectra. Most studies on soil P forms differentiate between Ca-bound P (e.g. apatite), organic P, Fe-bound P, and Al-bound P. In our analysis of a Ca, Al, and P rich soil from the Kohala region of Hawaii, we identified the mineral crandallite, CaAl₃(PO₄)₂(OH)₅·H₂O, a mineral previously not considered to play a significant role in soils. Crandallite was first identified with powder X-ray diffraction. Subsequently reference spectra were collected, and the presence of crandallite was confirmed using micro-focused P <em>K</em>-edge X-ray absorption near edge structure (XANES) spectroscopy, micro-infrared spectroscopy, and solid-state ³¹P nuclear magnetic resonance (NMR) spectroscopy. Crandallite XANES spectra were distinct from other common XANES spectra due to the presence of features in the post-edge region of the spectrum. Linear combination fitting of bulk P <em>K</em>-edge XANES spectra allowed the determination of the proportion of crandallite to the total P content, indicating that crandallite comprises up to half, possibly even more of the soil P in the samples. Crandallite is therefore an important and potentially overlooked component of soil P, which pedogenically forms in soils with high P, Al, and Ca contents, where it could play an important role in P bioavailability.</div></div>","PeriodicalId":12511,"journal":{"name":"Geoderma","volume":"467 ","pages":"Article 117712"},"PeriodicalIF":6.6,"publicationDate":"2026-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146152893","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":"Regional patterns of soil magnetic susceptibility and color in the Itacaiúnas River Watershed: Geological influences and practical applications","authors":"Paula Godinho Ribeiro ,&nbsp;Gabriel Negreiros Salomão ,&nbsp;Sérgio Henrique Godinho Silva ,&nbsp;Gabriel Caixeta Martins ,&nbsp;Luiz Roberto Guimarães Guilherme ,&nbsp;Marcio Sousa da Silva ,&nbsp;Silvio Junio Ramos ,&nbsp;Roberto Dall’Agnol","doi":"10.1016/j.geoderma.2026.117722","DOIUrl":"10.1016/j.geoderma.2026.117722","url":null,"abstract":"<div><div>Magnetic susceptibility (MS) is directly related to magnetic minerals in soils, primarily magnetite and maghemite. Determining MS and soil color is easy and cost-effective using sensors. They have great potential in agriculture, mining, and pedometrics, as they provide numerical characterization of these properties and can be correlated with other soil attributes. This study aimed to determine MS and color of surface (SS) and subsurface (SP) soil samples from a regional geochemical survey of the Itacaiúnas River Watershed, Carajás Mineral Province, and deduce relationships between these properties and soil chemical element contents and geological features. A total of 1204 composite samples from 602 locations at depths of 0–20 cm (SS) and 30–50 cm (SP) were selected for study. For MS determination, samples were analyzed at low frequency (0.47 kHz) and color numerical determination was quantified using a portable colorimeter sensor. The MS variations were strongly associated with local geology. Higher MS values were found along two east–west-oriented zones corresponding to northern and southern hydrothermal copper belts. These belts host iron oxide–copper–gold (IOCG) mineralization, where magnetite is systematically present among hydrothermal minerals. Reddish soils exhibit a spatial distribution similar to samples with higher MS values, indicating soil color indirectly reflects magnetic mineral content. MS and soil redness (a* International Commission on Illumination parameter) were positively correlated with Cu, Fe, Ni, and other elements, highlighting their potential for soil monitoring, although correlation strength varied among geological domains. These findings contribute to a soil MS database for the Amazon and may refine existing geological maps, while also indicating MS as an indicator of IOCG mineralization potential to guide new prospecting efforts.</div></div>","PeriodicalId":12511,"journal":{"name":"Geoderma","volume":"467 ","pages":"Article 117722"},"PeriodicalIF":6.6,"publicationDate":"2026-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146160814","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":"The impact of grazing and fertilization intensity on functional trait diversity and assembly processes of soil mesofauna in grasslands","authors":"Dennis Baulechner ,&nbsp;Katharina John ,&nbsp;Andrey Zaitsev ,&nbsp;Ruslan Saifutdinov ,&nbsp;Volkmar Wolters","doi":"10.1016/j.geoderma.2026.117715","DOIUrl":"10.1016/j.geoderma.2026.117715","url":null,"abstract":"<div><div>Assessing the impact of land-use intensification on soil communities is important for developing conservation strategies to maintain grassland ecosystem functioning. We aimed to establish a trait-based mechanistic understanding of how soil community composition responds to varying grazing and fertilization intensity, and whether this alters assembly processes of soil microarthropod metacommunities (Collembola and Oribatida). Microarthropods were sampled at 150 grassland plots of the German DFG Biodiversity Exploratories, covering gradients in three regions (north, centre, south).</div><div>First, functional community responses (functional richness, functional dispersion) to grazing and fertilization gradients were analysed using a trait-based approach. Hierarchical assembly models then estimated contributions of stochastic (dispersal-driven) vs. niche-based (environmental filtering, limiting similarity) processes. We compared low- vs. high-intensity plots to test whether trait-based responses shifted assembly processes. Trait–environment relationships were assessed using RLQ analyses.</div><div>Increased grazing reduced functional diversity and increased similarity in collembolan communities. Environmental filtering dominated Collembola assembly in intensively grazed grasslands in north and central Germany, but not in the south. Grazing had no effect on oribatid assembly processes. The strength of environmental filtering was region-specific. Fertilizer input was positively correlated with functional richness in Collembola but not Oribatida. Environmental filtering contributed less to Collembola assembly in intensively fertilized than unfertilized sites, suggesting low nutrient availability limits community structure.</div><div>Oribatida appeared more resistant to land-use change than Collembola. We conclude that grazing intensification reduces soil microarthropod functional diversity. Under high-intensity use, this promotes environmental filtering (especially for Collembola), altering assembly processes. Medium-intensity grazing reduced some functional groups but communities remained more resilient than at high-intensity sites, where filtering excluded entire groups. We recommend reducing high-intensity grazing to conserve soil biodiversity and ecosystem functioning.</div></div>","PeriodicalId":12511,"journal":{"name":"Geoderma","volume":"467 ","pages":"Article 117715"},"PeriodicalIF":6.6,"publicationDate":"2026-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146160815","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":"Intensive smooth cordgrass removal strengthens tidal and temperature impacts on methane emission","authors":"Yueting Deng ,&nbsp;Ruichen Lin ,&nbsp;Han Yang ,&nbsp;Hui Luo ,&nbsp;Lulu Song ,&nbsp;Xudong Zhu","doi":"10.1016/j.geoderma.2026.117719","DOIUrl":"10.1016/j.geoderma.2026.117719","url":null,"abstract":"<div><div>The world’s largest ecosystem restoration via intensive removals of invasive smooth cordgrass (<em>Spartina alterniflora</em>) is being implemented in coastal China, potentially exerting a large impact on soil biogeochemical cycles of greenhouse gases including methane (CH₄). However, the degree to which CH₄ emission and its environmental controls change with such anthropogenic disturbances has been rarely assessed with direct empirical evidence. To quantify these disturbance effects, we utilized the eddy covariance (EC) approach to continuously measure net CH₄ exchange from Jul. 2022 to Oct. 2023, covering both pre- and post-removal periods, in a disturbed coastal wetland of Southeast China experiencing an intensive cordgrass removal in late Oct. 2022. Our analyses, based on this unique EC dataset of high-frequency (30-min) time series CH₄ fluxes, revealed that (a) the removal caused a pulse of CH₄ emission peaking one month later up to 0.76 g CH₄ m⁻² d^-1, with the mean post-removal emission over ten times that of the pre-removal level (0.03 g CH₄ m⁻² d^-1); (b) the removal intensified the controls of tidal inundation and pumping on CH₄ fluxes, showing much stronger pumping effects within two months following the disturbances; (c) the removal also enlarged the temperature sensitivity of CH₄ emission, leading to larger daytime emission especially at afternoon hours; (d) the combination of enhanced tidal impacts and temperature dependence thus promoted the diel variability of CH₄ fluxes during the post-removal period. These results suggest that coastal restoration via intensive cordgrass removals boosts both the magnitude and the diel variability of CH₄ emission, highlighting the necessity of better understanding the climate impact of restoration activities. Future longer flux data with extended years are needed to further assess potential regime shift in soil CH₄ biogeochemistry and long-term evolution of such unintended environmental costs of the restoration.</div></div>","PeriodicalId":12511,"journal":{"name":"Geoderma","volume":"467 ","pages":"Article 117719"},"PeriodicalIF":6.6,"publicationDate":"2026-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146146752","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":"Differential responses of prokaryotic and fungal communities in soil microenvironments to drying and wetting as affected by soil aggregate isolation method","authors":"Jonathan Y. Lin ,&nbsp;Daoyuan Wang ,&nbsp;Cameron K. McMillan ,&nbsp;King C. Law ,&nbsp;Kate M. Scow ,&nbsp;Jorge L. Mazza Rodrigues","doi":"10.1016/j.geoderma.2026.117723","DOIUrl":"10.1016/j.geoderma.2026.117723","url":null,"abstract":"<div><div>Microorganisms live in communities within and on the surface of soil aggregates of varying sizes. A growing body of evidence suggests that different size fractions of aggregates are habitats for distinct microbial communities, but comparisons have been difficult owing to different aggregate separation methods. Two aggregate isolation methods, dry and wet sieving, originating from field moist and dried soils were used to investigate their effects on the prokaryotic and fungal communities in four aggregate size fractions (large macroaggregates (&gt;2000 μm), small macroaggregates (250–2000 μm), microaggregates (53–250 μm), and silt &amp; clay (&lt;53 μm)) using metabarcoding of the 16S rRNA gene and internal transcribed spacer. While prokaryotic community composition among treatments in each of the four size fractions was different, the composition and alpha diversity for fungi were more resistant to change in large and small macroaggregates than in the microaggregate and silt &amp; clay fractions. The average prokaryotic ribosomal RNA copy number and genome size increased in all aggregate size fractions when soils were dried before sieving. Decisions on which aggregate separation method to use depend heavily on the questions one is interested in, but soil storage conditions between sample collection and sieving are highlighted as driving the biggest differences in microbial community composition.</div></div>","PeriodicalId":12511,"journal":{"name":"Geoderma","volume":"467 ","pages":"Article 117723"},"PeriodicalIF":6.6,"publicationDate":"2026-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146152898","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":"Different mechanisms of phosphorus transformation in calcareous and acid soils affected by ammonium polyphosphate","authors":"Yang Luo,&nbsp;Yaoli Su,&nbsp;Minghui Huang,&nbsp;Yang Li,&nbsp;Dehua Xu,&nbsp;Zhengjuan Yan,&nbsp;Xinlong Wang","doi":"10.1016/j.geoderma.2026.117718","DOIUrl":"10.1016/j.geoderma.2026.117718","url":null,"abstract":"<div><div>The effects of ammonium polyphosphate (APP, (NH₄)_n+2P_nO_3n+1, n &lt; 20) on soil phosphorus (P) availability vary depending on polymerization distributions and the soil type, yet the mechanisms driving these differences remain unclear. This study explored the availability and transformation of P affected by APP1 (P species of P₁-P₂) and APP2 (P species of P₁-P₇) in two different soils, in comparison with conventional ammonium phosphates (APs). APP application increased Olsen-P by 10.7–24.8% in calcareous soil, but decreased it by 2.6–10.8% in acid soil relative to APs. In calcareous soil, APP significantly increased soluble-P, adsorbed-P, and Fe-associated P, as reflected by CaCl₂, NaHCO₃, and NaOH extractable Ps, while decreased more stable Ca-associated P and occluded P indicated by NH₄Ac and Na₃C₆H₅O₇-Na₂S₂O₄-NaOH extractable Ps. The changes in the composition of CaCO₃ and Fe/Al oxides together with/without the reduced organic carbon loss mainly contributed to the decrease in P sorption/precipitation and the increase in P desorption/dissolution. In acid soil, APP significantly increased microbial biomass P, leading to reduced labile inorganic P and elevated labile organic P. Meanwhile, APP increased both oxalate-extractable and complex Fe/Al oxides, which affected P adsorption–desorption to a certain extent. Compared to APP1, APP2 resulted in P existing in a more labile adsorbed state, thereby increasing P availability in both calcareous and acid soils. The main processes affecting P availability in the calcareous soils were abiotic transformations, while biotic transformations played the key role in the acid soils.</div></div>","PeriodicalId":12511,"journal":{"name":"Geoderma","volume":"467 ","pages":"Article 117718"},"PeriodicalIF":6.6,"publicationDate":"2026-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146146753","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":"Subsoiling reduces N2O emissions by altering the relative gas diffusivity, O2 status and microbial communities in grazed pasture soil","authors":"Juan Liu ,&nbsp;Timothy Clough ,&nbsp;Sam Carrick ,&nbsp;Jiafa Luo ,&nbsp;Andriy Podolyan ,&nbsp;Naomi Wells ,&nbsp;Chris Chisholm ,&nbsp;Jupei Shen ,&nbsp;Peng Li ,&nbsp;Lianfeng Du ,&nbsp;Hong Pan ,&nbsp;Limei Zhang ,&nbsp;Hong J. Di","doi":"10.1016/j.geoderma.2026.117716","DOIUrl":"10.1016/j.geoderma.2026.117716","url":null,"abstract":"<div><div>Nitrous oxide (N₂O) is a potent greenhouse gas predominantly emitted from grazed pasture through denitrification, driven by soil oxygen (O₂) availability and urine-derived nitrogen (N). Pasture soils are vulnerable to compaction from animal treading, restricting gas diffusion and enhancing N₂O emissions. Although subsoiling alleviates compaction, its impact on soil O₂ status and N₂O emissions, particularly under high urine N load, remain poorly understood and rarely investigated. This in-situ field study (March-August 2023) evaluated the effect of subsoiling on soil moisture, O₂ content, relative gas diffusivity (D_p/D_o), functional gene abundance, N₂O emissions, and pasture production. Treatments included non-subsoiling or subsoiling, each with or without synthetic ruminant urine (713 kg N ha⁻¹). Subsoiling improved macroporosity, enhanced O₂ availability, increased D_p/D_o at 5, 10 and 20 cm depth (<em>P &lt; 0.001</em>), and reduced moisture at 10 cm depth (<em>P &lt; 0.001</em>). Subsoiling significantly reduced N₂O emissions by 52% and 81% of non-subsoiled plots for non-urine and urine treatments, respectively (<em>P &lt; 0.05</em>). D_p/D_o was strongly correlated with N₂O fluxes during the first 15 days following urine application (<em>R² = 0.59</em>–<em>0.87</em>), suggesting its utility as a predictive indicator under high substrate availability. Molecular analysis showed reduced <em>nirK</em> gene abundance under subsoiling, with limited response for other denitrification genes. Subsoiling had no significant effect on pasture yield or N uptake. Overall, subsoiling mitigates N₂O emissions by improving soil aeration and D_p/D_o while maintaining productivity, offering a promising strategy for sustainable N management in grazed pasture soils.</div></div>","PeriodicalId":12511,"journal":{"name":"Geoderma","volume":"467 ","pages":"Article 117716"},"PeriodicalIF":6.6,"publicationDate":"2026-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146134156","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":"Selecting the right samples rather than more samples: A new spectral–environmental similarity strategy for local soil spectral modeling","authors":"Liangyi Li ,&nbsp;Zipeng Zhang ,&nbsp;Minglu Sun ,&nbsp;Jianli Ding ,&nbsp;Jingzhe Wang ,&nbsp;Dong Xu ,&nbsp;Yuanyuan Huang","doi":"10.1016/j.geoderma.2026.117710","DOIUrl":"10.1016/j.geoderma.2026.117710","url":null,"abstract":"<div><div>Addressing the dual challenges of limited sample size and high environmental heterogeneity in small-scale soil organic carbon (SOC) spectral modeling, this study proposes a fundamental hypothesis: selecting samples that are similar to the target region in both “spectral features and environmental characteristics” is more effective for improving prediction accuracy and stability. Based on this assumption, we developed a synergistic sample transfer strategy that integrates spectral similarity with environmental similarity under the Third Law of Geography, aiming to systematically screen the most comparable samples from the global soil spectral library to enhance the performance and robustness of local SOC modeling. A spectral-environmental similarity framework was established to identify samples that are simultaneously similar to the target region in spectral properties and environmental settings, and instance-based transfer modeling experiments were conducted in five representative small-sample regions (A-E). Results show that the synergistic strategy significantly improved modeling performance in most regions, with maximum increases in predictive power (as indicated by R²) of up to 18% compared with the baseline global transfer model. Remarkably, even when the number of global samples was reduced from 20,961 to around 200, the proposed strategy still outperformed local modeling and conventional global modeling approaches. In relatively stable environments, higher weights on environmental similarity yielded the best models, whereas in highly heterogeneous regions, spectral similarity played a more dominant role. The synergistic strategy also optimized the distribution of important spectral bands, enhanced SOC-responsive features in the visible region (450–750 nm), suppressed redundant information, and improved modeling efficiency. This study demonstrates that the proposed spectral-environmental synergistic sample transfer modeling method not only challenges the conventional assumption that “more samples guarantee better models” but also provides a novel pathway and theoretical support for the efficient use of global soil spectral libraries in regional SOC modeling.</div></div>","PeriodicalId":12511,"journal":{"name":"Geoderma","volume":"467 ","pages":"Article 117710"},"PeriodicalIF":6.6,"publicationDate":"2026-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146134155","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}