Geoderma最新文献

{"title":"Effects of water conservation methods on soil amelioration and crop yield in saline–alkali soil across China: A meta-analysis","authors":"Weihao Dou ,&nbsp;Ran Li ,&nbsp;Chen Guo ,&nbsp;Yonggan Zhao ,&nbsp;Wan Geng ,&nbsp;Liebao Han ,&nbsp;Wenchao Zhang","doi":"10.1016/j.geoderma.2026.117705","DOIUrl":"10.1016/j.geoderma.2026.117705","url":null,"abstract":"<div><div>Saline‒alkali soil is widespread and pose a major constraint to crop production. Nevertheless, as a substantial reserve of cultivable land, their reclamation plays a pivotal role in mitigating land scarcity, safeguarding food security, and promoting sustainable ecological development. With the development of irrigated agriculture, flood irrigation, drip irrigation and other water conservation methods are often used to ameliorate saline‒alkali soils. Nevertheless, an insufficient understanding of the efficacy, limitations, and contextual applicability of these methods when used indiscriminately, may render these interventions ineffective and trigger secondary soil salinization and alkalization processes. We employed a <em>meta</em>-analysis and linear regression to quantify the effects of typical water conservation methods (included various forms of drip and flood irrigation, with or without salinity or drainage) on soil properties (salinity, alkalinity, nutrient) and crop yield in saline–alkali soils across China, and to clarify the relationships among these effects. The results indicated that water conservation methods significantly reduced the soil electrical conductivity (EC, −10.0%), soil salt content (SSC, −65.0%), pH (−4.2%), and sodium adsorption ratio (SAR, −42.3%) while notably increasing the soil nutrient content (73.1%) and crop yield (13.3%). Among these methods, conventional drip irrigation and film-mulched drip irrigation reduced soil salinity and alkalinity and increased crop yield the most. Notably, saline water irrigation exhibited unstable ameliorative effects with potential secondary salinization risks, accompanied by yield suppression. The impoundment method decreased the SSC (−56.4%), pH (−7.3%), establishing a viable pathway for the amelioration of saline–alkali soil. However, the combination of flood irrigation with drainage method had a more positive effect on saline–alkali soils than the combination of drip irrigation with drainage. The results of regression analysis revealed that the reduction of soil salinity and alkalinity by water conservation methods improved soil fertility, thereby enhancing crop yields. This study provides theoretical support for the formulation of site-specific strategies to develop resource-efficient and eco-friendly agriculture.</div></div>","PeriodicalId":12511,"journal":{"name":"Geoderma","volume":"466 ","pages":"Article 117705"},"PeriodicalIF":6.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146048417","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":"Number and dissimilarity of soil amendments influence soil properties and plant communities in a greenhouse experiment","authors":"Huiying Li ,&nbsp;Rebecca Rongstock ,&nbsp;Anika Lehmann ,&nbsp;Inga Simon ,&nbsp;Emma Ring ,&nbsp;Anja Wulf ,&nbsp;Stefanie Maaß ,&nbsp;Matthias C. Rillig","doi":"10.1016/j.geoderma.2026.117703","DOIUrl":"10.1016/j.geoderma.2026.117703","url":null,"abstract":"<div><div>Soil health is fundamental in supporting plant diversity and productivity. In turn, a species-rich plant community enhances soil functions and is crucial in sustainable ecosystem management. However, soil degradation increases globally, raising the need for soil restoration. This study aims to test whether improving soil properties through multiple soil amendments promotes a species-rich plant community. We find that the diversity of amendments drives the changes in plant community composition, enhancing species richness, increasing herb and legume biomass, while reducing grass biomass. However, modifications in soil properties, such as water stable aggregates, water holding capacity and soil pH, are influenced by the number of amendments. Aligned with our findings, we observe that greater dissimilarity between restoration amendments results in more synergistic interactions for total above- and below-ground biomass. Our work emphasizes the mechanistic interactions of multiple soil amendments, providing actionable approach to enhance soil multifunctionality and support more targeted restoration strategies.</div></div>","PeriodicalId":12511,"journal":{"name":"Geoderma","volume":"466 ","pages":"Article 117703"},"PeriodicalIF":6.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146048418","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":"A bimodal model for thermal conductivity as a function of matric potential incorporating adsorption and capillarity","authors":"Yongwei Fu ,&nbsp;Wenjie Li ,&nbsp;Yili Lu ,&nbsp;Hu Zhou ,&nbsp;Tusheng Ren ,&nbsp;Joshua Heitman ,&nbsp;Robert Horton","doi":"10.1016/j.geoderma.2026.117677","DOIUrl":"10.1016/j.geoderma.2026.117677","url":null,"abstract":"<div><div>Estimating soil thermal conductivity (λ) in relation to soil water matric potential (<em>h</em>) is important to understand energy transfer, water movement, and ecological processes in soils. However, there is a lack of universally applicable λ(<em>h</em>) relationships that characterize soil thermal behavior across the full <em>h</em> range, particularly for soils with diverse textural classes and varying bulk density. In this study, we present the Boltzman-Tani (BoT) model, a physically based and continuous framework that captures the bimodal pattern of λ (pF, the common logarithm of |<em>h|</em>) relationship over the entire <em>h</em> range by incorporating both adsorption and capillarity. The BoT model parameters pF_ads and pF_cap, which mark the inflection points in the adsorption and capillary domains, respectively, have clear physical meanings and are linked to key soil thermal and hydraulic properties, i.e., critical and hydraulic continuity water contents. We evaluate the BoT model using a λ(pF) dataset comprising 246 observations from 18 soil samples, representing a wide range of texture and bulk density. The BOT model outperforms two existing models: the unified exponential model and the two-segment power model, achieving the least root mean square error (0.043 W m⁻¹ K⁻¹) and mean error (0.033 W m⁻¹ K⁻¹), the lowest Akaike Information Criterion (−82.2), and the highest coefficient of determination (0.983). The changes in λ are driven by variations in the adsorption and capillary components, with adsorptive force dominating at higher pF and capillary force becoming more influential at lower pF, validating the model’s theoretical framework. Furthermore, we develop pedo-transfer functions to estimate the BoT model parameters from soil texture and bulk density, which facilitates its broader and practical application such as soil-climate feedback and optimizing land management. Future work should focus on validating the model with larger, independent datasets and exploring its integration with advanced machine learning techniques to expand its predictive capabilities.</div></div>","PeriodicalId":12511,"journal":{"name":"Geoderma","volume":"466 ","pages":"Article 117677"},"PeriodicalIF":6.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146000550","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":"Carbon-phosphorus stoichiometric imbalance induced by manure amendment enhances microbial phosphorus mobilization and crop phosphorus uptake","authors":"Wangzun Chen ,&nbsp;Yanlong Li ,&nbsp;Yi Peng ,&nbsp;Letian Wang ,&nbsp;Gu Feng","doi":"10.1016/j.geoderma.2026.117711","DOIUrl":"10.1016/j.geoderma.2026.117711","url":null,"abstract":"<div><div>Fertilization alters soil stoichiometric ratios, shaping microbial processes and phosphorus (P) dynamics, yet the underlying mechanisms remain poorly understood. Here, we conducted a three-year maize field experiment on the North China Plain, to test how P-based manure amendments modified soil C:P ratio, intensified microbially mediated soil P mobilization and turnover processes, and improved crop P uptake and yield. There were four treatments as follows: P0, no P fertilizer; P1, 39.27 kg ha⁻¹ of chemical P; LCP, with a total P input of 39.27 kg P ha⁻¹, input 0.76 t ha⁻¹ manure C; and HCP, with a total P input of 39.27 kg P ha⁻¹, input 1.53 t ha⁻¹ manure C. Our results suggested that manure C inputs significantly increased the content of soil dissolved organic carbon (DOC) and induced a shift in microbial community composition from oligotrophic (Acidobacteria) to copiotrophic taxa (Proteobacteria, Bacteroidetes, Myxococcota), accompanied by increased microbial biomass P. Manure amendment significantly raised the soil C:P ratio, but the microbial C:P ratio remained relatively stable across treatments. The induced C:P imbalance intensified microbial P limitation, exerting selective pressure on soil microbes preferential investment in P mobilization. Through the coordinated regulation of microbial community composition and function, manure amendment enhanced the bioavailable P pool and increased plant P acquisition. By increasing soil C:P ratios relative to full chemical fertilization, P-based manure amendment increased maize yield by 12%, improved P fertilizer recovery efficiency from 81.34% to 97.06%, enhanced P fertilizer utilization efficiency from 22.01% to 36.69%, and reduced soil P accumulation from 7.35 to 1.15 kg P ha⁻¹ year⁻¹. These findings suggest that manure-induced stoichiometric imbalance triggers a priming effect on indigenous microbial P mobilization, providing an ecologically intensive pathway to enhance fertilizer P use efficiency, reduce environmental P loading, and improve crop productivity.</div></div>","PeriodicalId":12511,"journal":{"name":"Geoderma","volume":"466 ","pages":"Article 117711"},"PeriodicalIF":6.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146134163","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":"Commentary: Structural equation models and causal claims in soil science and biogeochemistry – An equation-free “how to”","authors":"Jordon Wade ,&nbsp;Teal M. Potter ,&nbsp;Andrew J. Margenot","doi":"10.1016/j.geoderma.2026.117702","DOIUrl":"10.1016/j.geoderma.2026.117702","url":null,"abstract":"<div><div>Structural equation modeling (SEM) is a set of approaches that have seen exponential usage in the soil sciences as well as the related fields of agriculture and biogeochemistry. When correctly used and interpreted, SEM can be a powerful and flexible tool to test complex hypotheses on causality. However, the recent explosion of SEM usage in the soil sciences facilitated by user-friendly statistical programs has not been fully met by statistical expertise of users, reviewers and editors, ultimately leading to widespread contamination of the literature with inappropriate modeling and inflated or unfounded causal claims. The rise of such “SEM slop” poses a serious risk of an unreliable knowledge base and also undermines efforts and standards on what constitutes causality in the soil sciences. To address this, we diagnose major pitfalls in SEM, with an eye towards considerations specific to soil sciences, categorizable as three types: (1) <em>Causal claims</em>, including not satisfying causal criteria, lack of justified a priori models, not considering counterfactuals, and unqualified causal language; (2) <em>Experimental design</em>, including use in randomized complete block designs without complete pooling or multi-level models, inappropriate data type (e.g., ontological misalignment), and insufficient sample size; and, (3) <em>Assessing the model</em>, including incomplete or inappropriate model evaluation, non-qualified use of modification indices, and lack of robustness tests. There is a dual imperative for users as well as reviewers and editors to better implement and evaluate SEMs <em>and</em> claims of causality made with SEMs. To support this, we offer best practices and practical considerations on these three major pitfalls. These best practices will help SEM be appropriately employed as a powerful, nuanced statistical tool that benefits the soil science community.</div></div>","PeriodicalId":12511,"journal":{"name":"Geoderma","volume":"466 ","pages":"Article 117702"},"PeriodicalIF":6.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146110572","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":"Deep amelioration of compaction and acidity doubled the water use efficiency of cereal crops on a sandy soil in a long-term experiment in a water-limited environment","authors":"Gaus Azam ,&nbsp;Md. Shahinur Rahman ,&nbsp;Craig Scanlan ,&nbsp;Md. Hasinur Rahman ,&nbsp;Ross Gazey ,&nbsp;Edward G. Barrett-Lennard ,&nbsp;Kanch Wickramarachchi ,&nbsp;Bob Nixon ,&nbsp;Chris Gazey","doi":"10.1016/j.geoderma.2026.117700","DOIUrl":"10.1016/j.geoderma.2026.117700","url":null,"abstract":"<div><div>The co-occurrence of subsoil compaction and acidity commonly decreases the yield and water use efficiency (WUE) of agricultural crops around the world, yet the benefits of the complete amelioration of these constraints on yield and WUE remain unclear. We conducted a long-term field experiment in Western Australia (WA) to evaluate the effects of the complete removal of subsoil compaction and acidity through soil profile re-engineering — involving soil removal, replacement, and lime incorporation — on root architecture, yield, and WUE in wheat (<em>Triticum aestivum</em> L.) and barley (<em>Hordeum vulgare</em> L.). Treatments included an untreated control, and soil loosening to 0.45 m depth and lime incorporation at three depths combined with loosening (0.45 m). Results showed that the improvements in soil conditions through soil re-engineering were maintained for seven years. In the control, the roots of cereal crops were confined to the top 0.2–0.3 m of soil, while soil re-engineering tripled the rooting depth and created a more uniform root distribution. The removal of compaction improved wheat root architecture but did not affect barley. These improvements increased yield and WUE up to 3.7-fold, and the benefits occurred in every season. In the best treatment, wheat yield ranged from 945 to 4164 kg ha⁻¹ and WUE from 16.9 to 33.3 kg mm⁻¹, compared with 252–1722 kg ha⁻¹ and 6.5–13.0 kg mm⁻¹ in the control. Moreover, the best treatments substantially exceeded the expected yields of crops grown under comparable climatic conditions, based on two independent published datasets from WA and southern Australia. Our findings show that soil re-engineering can sustainably improve yield and WUE on coarse-textured sandy soils with multiple subsoil constraints for the long-term in water-limited environments. While this approach may not be directly scalable or economically feasible, it provides a foundation for the development of more comprehensive tillage machinery suitable for large scale soil profile re-engineering.</div></div>","PeriodicalId":12511,"journal":{"name":"Geoderma","volume":"466 ","pages":"Article 117700"},"PeriodicalIF":6.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146048419","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":"Assessing global passive microwave soil moisture retrievals in mountainous terrain: insights from in situ validation and extended triple collocation","authors":"Yanqing Yang ,&nbsp;Wei Zhao ,&nbsp;Tao Ding ,&nbsp;Jiujiang Wu ,&nbsp;Junli Zhao","doi":"10.1016/j.geoderma.2026.117707","DOIUrl":"10.1016/j.geoderma.2026.117707","url":null,"abstract":"<div><div>Soil moisture (SM) conditions are closely linked to water availability, energy balance, and ecosystem processes, highlighting the importance of accurate SM data for hydrological modeling and environmental monitoring. Passive microwave products offer large-scale SM estimates, but their validation in mountainous areas remains difficult due to sparse in situ data and complex terrain. This study systematically evaluated three global passive microwave soil moisture products—SMAP, SMOS, and AMSR2—across mountainous regions by integrating in situ observations from the International Soil Moisture Network (ISMN) with the Extended Triple Collocation (ETC) method. Results indicated that SMAP and SMOS outperformed AMSR2 in both in situ and ETC-based evaluations, with higher median correlation coefficients (0.95 for SMAP, 0.84 for SMOS) and lower RMSEs (0.026 and 0.048 m3/m3, respectively). In the Rocky Mountains, where station density is highest, over 86% of sites showed consistent product rankings between in situ and ETC results, confirming the reliability of ETC in data-scarce areas. Further analysis revealed contrasting environmental controls: SMAP’s error increased with slope and vegetation density, while its sensitivity increased with elevation and surface roughness. SMOS showed more stable performance across gradients, whereas AMSR2 was more affected by terrain and vegetation complexity. These findings clarify uncertainty patterns and environmental controls on passive microwave soil moisture retrievals in mountainous regions, and provide insights for product selection, algorithm improvement, and data fusion in hydrological and ecological applications.</div></div>","PeriodicalId":12511,"journal":{"name":"Geoderma","volume":"466 ","pages":"Article 117707"},"PeriodicalIF":6.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146074611","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":"Pasture management in Ferralsols drives mineral-associated organic matter storage, exceeding native soil carbon stocks and enhancing cation exchange capacity","authors":"Lucas Raimundo Bento ,&nbsp;Ladislau Martin-Neto ,&nbsp;João Vitor dos Santos ,&nbsp;Vitor Silveira Freitas ,&nbsp;José Ricardo Macedo Pezzopane ,&nbsp;Alberto Carlos de Campos Bernardi ,&nbsp;Patrícia Perondi Anchão Oliveira ,&nbsp;Steffen A. Schweizer","doi":"10.1016/j.geoderma.2026.117678","DOIUrl":"10.1016/j.geoderma.2026.117678","url":null,"abstract":"<div><div>Pasture management is pivotal for enhancing soil organic carbon (SOC) storage in tropical grasslands, yet SOC recovery is often considered merely as the replenishment of historical losses following land-use change. It remains unclear whether managed Ferralsols can surpass the SOC stocks of native vegetation (NV) and which mechanisms drive such gains. We evaluated SOC pools, chemical composition, and nutrient-holding capacity after 24 years under unmanaged degraded pasture (DP) and fertilized managed pasture (MP), relative to NV. SOC storage in these systems was primarily mediated by the mineral-associated organic matter (MAOM) pool. Compared to NV, DP soils exhibited reduced MAOM stocks (119 vs. 92 Mg<!--> <!-->C<!--> <!-->ha⁻¹), whereas MP soils stored 148 <!--> <!-->Mg<!--> <!-->C<!--> <!-->ha⁻¹. In DP, soil acidity, low nutrient availability, and poor forage inputs induced microbial stress (as revealed by phospholipid fatty acid profiles), likely constraining MAOM formation and yielding MAOM enriched in carbohydrates with fewer carbonyl groups. In contrast, liming and fertilization in MP alleviated the Ferralsol’s low pH and nutrient deficiencies, enhancing forage yields and reducing microbial stress, likely promoting MAOM with more microbially processed signatures. NanoSIMS analyses revealed microscale organic matter patches sparsely covering clay-sized particles, indicating that SOC storage is decoupled from mineral surface area and highlighting the role of organic inputs and microbial activity in MAOM formation. Higher MAOM under MP not only increased SOC stocks but also enhanced cation exchange capacity, demonstrating that targeted pasture management can exceed native SOC stocks while improving nutrient retention.</div></div>","PeriodicalId":12511,"journal":{"name":"Geoderma","volume":"466 ","pages":"Article 117678"},"PeriodicalIF":6.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146014527","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":"Response of element cycling and budgets to nutrient additions in a tropical montane forest of Ecuador","authors":"Andre Velescu ,&nbsp;Jürgen Homeier ,&nbsp;Carlos Iván Espinosa ,&nbsp;Wolfgang Wilcke","doi":"10.1016/j.geoderma.2026.117698","DOIUrl":"10.1016/j.geoderma.2026.117698","url":null,"abstract":"<div><div>The tropical montane forests in southern Ecuador are subject to rising nitrogen (N), low phosphorus (P), and episodic calcium (Ca) deposition. To investigate the response of the vegetation, soil organic layer and mineral soil to 0.3 m depth to increased nutrient inputs, we initiated in 2008 an interdisciplinary Nutrient Manipulation Experiment (NUMEX) at 2000 m a.s.l. We have applied N as urea at 50 kg ha⁻¹ year⁻¹, P as NaH₂PO₄ at 10 kg ha⁻¹ year⁻¹, combined N and P at 50 + 10 kg ha⁻¹ year⁻¹, and Ca (as CaCl₂), at 10 kg ha⁻¹ year⁻¹. From 2008 to 2012, we set up annual budgets by calculating net fluxes of N, P, Ca and Na for the canopy, the organic layer and the mineral soil and determined δ¹⁵N values in the foliage of the four most abundant tree species, litterfall and organic layer. The addition of P and N + P increased P leaching from the canopy, suggesting a reduced retention of deposited P by canopy organisms. All added nutrients were largely retained in the soil organic layer and tightly cycled between the organic layer and the vegetation via litterfall and throughfall. The small leaching losses of N, P, Ca and Na from the organic layer were retained in the upper mineral soil. The retention of the added nutrients in the ecosystem indicated a strong nutrient demand. Nevertheless, the ¹⁵N enrichment in the organic layer was an early indicator of beginning N losses from the ecosystem by leaching and volatilization, which could not yet be detected by our flux-based budgeting approach.</div></div>","PeriodicalId":12511,"journal":{"name":"Geoderma","volume":"466 ","pages":"Article 117698"},"PeriodicalIF":6.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146033237","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":"Phosphorus dynamics in acidic and neutral fen soils − does vivianite limit phosphorus release?","authors":"Adrian F. Florea ,&nbsp;Dominik H. Zak ,&nbsp;Rasmus Jes Petersen ,&nbsp;Carolin L. Dreher ,&nbsp;Andreas Kappler ,&nbsp;Hans Christian B. Hansen","doi":"10.1016/j.geoderma.2026.117685","DOIUrl":"10.1016/j.geoderma.2026.117685","url":null,"abstract":"<div><div>Drainage and cultivation of organic lowland peat soils have profoundly altered their hydrological and biogeochemical functions, increasing greenhouse gas emissions and phosphorus (P) mobilization due to enhanced mineralization. Rewetting is increasingly promoted to mitigate these impacts. However, intensive agricultural use has led to P accumulation, primarily bound to Fe(III)(oxyhydr)oxide minerals, raising the risk of P release under anoxic conditions and challenging the restoration of these systems as nutrient sinks. Predicting P release remains difficult due to complex interactions, including P re-sorption to metal oxides with remaining P binding places and precipitation as Fe(II) or Ca phosphates such as vivianite and hydroxyapatite.</div><div>This study investigates Fe(III)(oxyhydr)oxide reduction extent and associated P mobilization in two contrasting Danish lowland peatlands over 24 months: the acidic Vejrumbro and neutral-alkaline Løvenborg. Oxalate-extractable Fe, Al, and P (Fe_ox, Al_ox, P_ox) differed substantially between sites. Løvenborg exhibited higher Fe_ox (198–241 mmol kg⁻¹) and Al_ox (41–49 mmol kg⁻¹) than Vejrumbro (Fe_ox: 27–122 mmol kg⁻¹; Al_ox: 4.5–40 mmol kg⁻¹), resulting in greater P sorption capacity (PSC: 239–287 vs. 44–155 mmol kg⁻¹). The degree of P saturation (DPS) remained low at both sites (&lt;10%).</div><div>Under winter or wet field conditions, Fe(III)(oxyhydr)oxide reduction extent reached up to 100%, indicating complete dissolution of the Fe_ox pool. Despite extensive reduction, soluble P (P_Sol) remained low in Løvenborg (≤0.3 mg L⁻¹), whereas Vejrumbro exhibited high P_Sol concentrations (up to 4.7 mg L⁻¹). Powder X-ray diffraction and Mössbauer spectroscopy confirmed vivianite formation in Løvenborg, demonstrating P immobilization via precipitation. Moreover, in Løvenborg, the saturation index calculated using the geochemical model Minteq showed values between 2.5 and 4.2 with respect to vivianite supersaturation, while for Ca-P precipitates such as hydroxyapatite, Løvenborg soils show near equilibrium (0.09) to slight undersaturation (−1.8). In contrast, P retention in Vejrumbro was mainly through adsorption onto residual Fe and Al oxide minerals.</div><div>These results indicate that P release risk models must go beyond re-adsorption, and include precipitation pathways, which depend on metal-oxide content, cation availability (e.g., Ca²⁺, Fe²⁺), pH, alkalinity, and the extent of Fe(III) reduction. Incorporating key geochemical indicators—such as pH, sorption capacity, calcium content, Fe(III) reduction extent, and alkalinity may lead to better classification of peat soils and guide rewetting strategies safeguarding minimal P release.</div></div>","PeriodicalId":12511,"journal":{"name":"Geoderma","volume":"466 ","pages":"Article 117685"},"PeriodicalIF":6.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146000552","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}