Soil Biology & Biochemistry最新文献

{"title":"Vegetation restoration shapes soil organic matter chemistry and microbial processes","authors":"Shuzhen Wang ,&nbsp;Wenxin Chen ,&nbsp;Kate V. Heal ,&nbsp;Jingjing Liang ,&nbsp;Weijuan Qiu ,&nbsp;Yuanchun Yu ,&nbsp;Chuifan Zhou","doi":"10.1016/j.soilbio.2025.109970","DOIUrl":"10.1016/j.soilbio.2025.109970","url":null,"abstract":"<div><div>Vegetation restoration is a critical process for the recovery of ecosystem functioning in red soil (Ultisol) erosion areas, yet the mechanisms underlying its effects on soil organic carbon (SOC) stability and nutrient cycling remain poorly understood. By integrating ¹³C-NMR spectroscopy, Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), and microbial necromass quantification, this study elucidates the dynamic coupling mechanisms among SOC composition, dissolved organic matter (DOM) molecular signatures, and microbial necromass carbon (MNC) across vegetation types and soil depths in red soil erosion areas of southern China. Vegetation restoration significantly decreased mean soil pH from 5.02 to 4.54 in topsoil (0–10 cm) (<em>P</em> &lt; 0.05). The dissolved organic carbon concentration in topsoil increased from 75.1 mg kg⁻¹ in the degraded site (CK) to 217 mg kg⁻¹ in broadleaf forest over 80 years old (BF) (<em>P</em> &lt; 0.05) and that of easily oxidizable carbon concentrations increased from 0.48 to 2.77 g kg⁻¹ (<em>P</em> &lt; 0.05). ¹³C-NMR analysis revealed a decline in the relative abundance of alkyl C in SOC with vegetation restoration, accompanied by an increase in O-alkyl C. DOM molecular characterization indicated that vegetation restoration promoted the accumulation of oxidized compounds (lignin- and tannin-like molecules) and reduced the abundance of reduced-state compounds (lipid- and protein/amino sugar-derived molecules). Thermodynamic analysis revealed that vegetation restoration decreased energy availability of DOM molecules. Vegetation restoration significantly enhanced MNC accumulation over 10-fold in both 0–10 cm and 20–40 cm soil layers compared to severely degraded zones (<em>P</em> &lt; 0.05). Vegetation restoration significantly increased bacterial Shannon diversity and drove a bacterial community-level transition toward <em>K</em>-strategists, evidenced by a significant shift in the <em>K:r</em> ratio from 0.29 to 9.20 in 0–10 cm soil layer (<em>P</em> &lt; 0.05). Moreover, the abundance of saprotroph-symbiotroph functional guilds in fungal communities increased with vegetation restoration. Path analysis confirmed that soil DOM parameters regulate microbial necromass accumulation and multi-nutrient cycling potential by mediating DOM ΔG⁰_Cox and functional diversity. This study elucidates how vegetation restoration enhances SOC stability and ecological function recovery in red soils by reshaping DOM molecular signatures and microbial life-history strategies. These findings provide a framework for understanding and promoting carbon sequestration mechanisms in erosion-prone ecosystems, emphasizing the critical role of fungal necromass and DOM thermodynamics in long-term soil C stabilization.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"211 ","pages":"Article 109970"},"PeriodicalIF":10.3,"publicationDate":"2025-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144996043","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":"Aggregate size mediates the stability and temperature sensitivity of soil organic carbon in response to decadal biochar and straw amendments","authors":"Yalan Chen ,&nbsp;Yakov Kuzyakov ,&nbsp;Qiwen Ma ,&nbsp;Zhangliu Du ,&nbsp;Ke Sun ,&nbsp;Keqing Xiao ,&nbsp;Xinru Liang ,&nbsp;Yang Li ,&nbsp;Yunxian Zhang ,&nbsp;Xianqiang Lai ,&nbsp;Wei Fu ,&nbsp;Bo Gao ,&nbsp;Fei Wang ,&nbsp;Shishu Zhu ,&nbsp;Qun Gao ,&nbsp;Matthias C. Rillig","doi":"10.1016/j.soilbio.2025.109969","DOIUrl":"10.1016/j.soilbio.2025.109969","url":null,"abstract":"<div><div>The temperature sensitivity (Q₁₀) of soil organic carbon (SOC) decomposition governs soil-climate feedbacks, yet how soil management mediates Q₁₀ through aggregate-scale processes remains unclear. Through a 14-year field experiment comparing biochar and maize straw amendments, we demonstrated that aggregate size critically mediated SOC stability and temperature responses. Biochar addition enhanced SOC sequestration by 49–110 % while suppressing mineralization by 4.9–14 %, primarily through preferential stabilization in small macroaggregates (SMA) and microaggregates (MA) (i.e., increased benzene polycarboxylic acids and decreased ¹⁴C age and δ¹³C). These small aggregates exhibited high SOC stability and low Q₁₀ due to enhanced mineral association, and elevated microbial carbon use efficiency (+11–39 %) for microbial necromass accrual (+35–92 %). By contrast, large macroaggregates (LMA) showed limited SOC sequestration capacity due to thermal disruption of Fe-associated SOC that led to high Q₁₀. Maize straw preferentially sequestered SOC in SMA through physical occlusion (i.e., 36 % increase in MAOM, 45 % increase in Fe-oxides) but increased bulk Q₁₀ by 89 % due to temperature-sensitive decomposition of labile straw-derived C. The correlation analysis indicated that while mineral protection reduced SOC mineralization across all aggregates, its concurrent increase in Q₁₀ highlighted a warming vulnerability tradeoff. Our findings establish that biochar outperforms straw in decoupling SOC turnover from warming through aggregate-specific stabilization pathways, providing critical insights for optimizing soil amendments to mitigate carbon-climate feedbacks in agricultural systems.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"211 ","pages":"Article 109969"},"PeriodicalIF":10.3,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144930608","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":"Tropical tree-mycorrhizal types show divergent phosphorus adaptive strategies after 12-year simulated acid rain","authors":"Yuanliu Hu ,&nbsp;Ji Chen ,&nbsp;Dafeng Hui ,&nbsp;Ying-Ping Wang ,&nbsp;Xiaolin Huang ,&nbsp;Minghui Hu ,&nbsp;Yiren Zhu ,&nbsp;Yonghui Li ,&nbsp;Jianling Li ,&nbsp;Deqiang Zhang ,&nbsp;Qi Deng","doi":"10.1016/j.soilbio.2025.109968","DOIUrl":"10.1016/j.soilbio.2025.109968","url":null,"abstract":"<div><div>Acid rain is believed to exacerbate phosphorus (P) limitation in tropical forests, but how tropical trees respond and adapt to acid-induced P limitation, particularly after long-term acid rain events, remains poorly understood. We conducted a 12-year simulated acid rain (SAR) experiment by irrigating plots with water of different pH values (i.e., 3.0, 3.5, 4.0, and 4.5 as a control) in a tropical forest in southern China. Five tree species associated with either ectomycorrhizal (ECM) or arbuscular mycorrhizal fungi (AMF) were chosen to examine the changes of P fractions in their rhizosphere soils and green leaves. In ECM tree rhizospheres, SAR treatments significantly increased labile P by 27.3 % (<em>p</em> &lt; 0.05) and decreased occluded P by 11.7 % (<em>p</em> &lt; 0.05), which were positively correlated with increased phosphodiesterase activity and related gene abundance. However, in AMF trees, SAR treatments significantly reduced rhizosphere available P and foliar P by 45.9 % and 28.7 % (<em>p</em> &lt; 0.05 for both), respectively. In response, AMF trees exhibited greater plasticity in foliar P fractions than ECM trees, shifting from structural P (phospholipids and phosphorylated proteins) to metabolic P (P-containing metabolites and nucleic acid P) fractions under SAR treatments. These findings suggest that, to cope with acid-induced P limitation, ECM trees tend to adopt an acquisitive nutrient-use strategy for greater P mobilization, while AMF trees favor a conservative strategy with more efficient foliar P utilization.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"211 ","pages":"Article 109968"},"PeriodicalIF":10.3,"publicationDate":"2025-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144928468","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":"Tree-mycorrhizal types differ in their biomass response to nitrogen addition","authors":"Guoyin Chen ,&nbsp;Yuanliu Hu ,&nbsp;Jianping Wu ,&nbsp;Richard P. Phillips ,&nbsp;Jianyang Xia ,&nbsp;Ying-Ping Wang ,&nbsp;Dafeng Hui ,&nbsp;Jianling Li ,&nbsp;Xianyu Yao ,&nbsp;Qi Deng","doi":"10.1016/j.soilbio.2025.109967","DOIUrl":"10.1016/j.soilbio.2025.109967","url":null,"abstract":"<div><div>Increasing nitrogen (N) deposition can stimulate forest productivity and carbon (C) sequestration in woody biomass, but the magnitude and global importance of this effect remain poorly quantified. By synthesizing 123 N addition experiments globally, we show that woody biomass C gain per unit N applied (hereafter “C_perN”) was best explained by tree-mycorrhizal association (i.e., trees associated with arbuscular mycorrhizal [AM] <em>vs</em>. ectomycorrhizal [ECM] fungi) and latitude. Overall, C_perN increased with latitude, and was ∼6-fold greater in AM than ECM trees due to their distinct N-acquisition strategies. Using a global map of tree-mycorrhizal distributions, we estimated that N-induced tree C sequestration was 12% lower globally and 17% lower in temperate forests when accounting for the divergent mycorrhizal-tree C_perN, compared to estimates that ignored these effects. This reduction was largely due to the predominance of ECM trees in many temperate forests. Our results suggest that in areas receiving high N loading, trees with more acquisitive nutrient use strategies (such as AM tree sepcies) may be better positioned to sequester more C than trees with more conservative nutrient use strategies (such as ECM tree species). Therefore, shifts in the relative abundance of AM <em>versus</em> ECM trees could be a critical determinant of the future forest C sink under continued N enrichment.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"211 ","pages":"Article 109967"},"PeriodicalIF":10.3,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144924258","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":"Tree species diversity enhances dark microbial CO2 fixation rates in soil of a subtropical forest","authors":"Xintong Xu ,&nbsp;Pengpeng Duan ,&nbsp;Xinyi Yang ,&nbsp;Dejun Li","doi":"10.1016/j.soilbio.2025.109966","DOIUrl":"10.1016/j.soilbio.2025.109966","url":null,"abstract":"<div><div>Tree species diversity (TSD) is crucial for modulating microbial processes and enhancing soil organic carbon (SOC) accumulation in forest ecosystems. However, the role of TSD in regulating dark microbial CO₂ fixation (DMCF), a key microbial pathway contributing to SOC formation, remains largely unexplored. Here, we conducted a¹³C–CO₂ labeling experiment across three CO₂ concentrations (2 %, 5 %, and 15 %) using soils from a gradient of TSD (Shannon index 0.15–3.57) in a subtropical forest. Our results revealed that DMCF rates averaged 0.27 μg C g⁻¹ soil day⁻¹ and 174.39 μg C g⁻¹ MBC day⁻¹, offsetting 0.67 %–6.16 % of total soil CO₂ emissions in a subtropical karst forest. DMCF rates were positively correlated with TSD at both 2 % and 5 % atmospheric CO₂ concentrations. In contrast, this positive relationship disappeared under 15 % CO₂, where DMCF rates peaked at intermediate TSD, suggesting a potential stress-induced decoupling. TSD influenced DMCF through its effects on soil properties, microbial communities, and SOC stability. Microbial biomass carbon and the abundance of gram-positive bacteria were identified as key drivers of DMCF, underscoring the significance of microbial community composition in regulating DMCF rates. These findings highlight the often-overlooked contribution of DMCF to SOC storage in subtropical forests and emphasize the role of TSD in enhancing SOC sequestration. This study provides novel insights into the mechanisms governing DMCF, challenging the assumption that biodiversity consistently enhances ecosystem functions under extreme climatic drivers.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"211 ","pages":"Article 109966"},"PeriodicalIF":10.3,"publicationDate":"2025-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144919631","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":"Planar optodes reveal spatiotemporal heterogeneity of oxic and pH microenvironments driven by dung beetle activity in soil","authors":"Gianluca Natta ,&nbsp;Theresa Merl ,&nbsp;Alex Laini ,&nbsp;Angela Roggero ,&nbsp;Antonio Rolando ,&nbsp;Claudia Palestrini ,&nbsp;Klaus Koren ,&nbsp;Ugo Marzocchi","doi":"10.1016/j.soilbio.2025.109965","DOIUrl":"10.1016/j.soilbio.2025.109965","url":null,"abstract":"<div><div>Dung beetles (Coleoptera, Scarabaeidae) contribute to soil biogeochemical cycling via dung burial and soil mixing, yet little is known about their impact on soil biogeochemistry at the microscale. We employed planar optode imaging to simultaneously resolve oxygen and pH gradients in soil bioturbated by the tunneling species <em>Onthophagus nuchicornis</em> (Linnaeus, 1758). Using a “soil sandwich” setup, we monitored spatial and temporal changes in the soil microenvironments across a vertical plane over 96 h. Beetles generated a heterogeneous network of tunnels and dung balls, leading to steep oxygen and pH gradients and an 8-fold increase in the 2D oxic-anoxic interface zones. Buried dung balls exhibited persistent anoxia, confirmed via microsensor profiling, with more than 75 % of the volume remaining anoxic for over 45 h. Oxygen depletion was coupled to a rise in pH extending millimeters beyond the anoxic zone. Using fluorescent dye-labeled nanoparticles we were also able to track dung movement under waterlogged conditions, demonstrating continued, albeit reduced, beetle activity under anoxia. The combined effects on oxygen, pH, and the organic matter redistribution enhance microbial habitat heterogeneity and are expected to favor the coupling between aerobic and anaerobic processes, such as nitrification and denitrification. Finally, we obtained quantitative estimates of soil displacement and dung removal, providing direct metrics of the ecosystem services delivered by dung beetles, including enhanced soil porosity and organic matter burial. The novel methodological approach described here provides mechanistic insights into the microscale processes underlying dung beetle-mediated soil modification, sustaining their role as soil ecosystem engineers.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"211 ","pages":"Article 109965"},"PeriodicalIF":10.3,"publicationDate":"2025-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144919653","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":"Challenges in integrating dissolved organic matter chemodiversity into kinetic models of soil respiration","authors":"Arjun Chakrawal ,&nbsp;Odeta Qafoku ,&nbsp;Satish Karra ,&nbsp;John R. Bargar ,&nbsp;Emily B. Graham","doi":"10.1016/j.soilbio.2025.109954","DOIUrl":"10.1016/j.soilbio.2025.109954","url":null,"abstract":"<div><div>The chemodiversity of dissolved organic matter (DOM) in soil has been proposed to influence the microbial metabolism and fate of belowground organic carbon (C). However, integrating DOM chemistry into soil C cycle models to improve predictions of C stocks and fluxes—beyond simply considering DOM pool size—remains a challenge. While recent research suggests that incorporating DOM chemodiversity into models can improve predictions of microbial respiration, there is still a lack of mechanistic understanding describing how DOM chemodiversity affects microbial metabolism and soil respiration. We evaluated whether DOM chemodiversity was a determinant of soil respiration using paired measurements of high-resolution DOM chemistry, obtained from Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS), and potential soil respiration rates from across the United States (U.S.), all data provided by the Molecular Observation Network. Our objectives were to (1) assess statistical relationships between DOM chemodiversity and microbial respiration, and (2) evaluate the ability of kinetic models to leverage DOM chemistry to explain empirical relationships found in statistical models.</div><div>Statistical regressions revealed that DOM chemodiversity (alpha diversity) was nonlinearly related to potential soil respiration rates, both independently and through its interactions with DOM and total C concentrations. In soils with relatively high DOM but low total C concentrations, potential soil respiration rates were negatively correlated with DOM alpha diversity, whereas in soils with relatively low DOM and high total C concentrations showed the opposite trend. However, when metabolic transition theory kinetic models were modified to include chemodiversity, their performance was comparable to traditional Monod kinetics approaches, which simulate respiration rates as a function of DOM concentration. The inability to account for nonlinearities in DOM chemodiversity–respiration relationships highlight an opportunity to advance substrate uptake kinetics by establishing causal links between DOM chemodiversity, microbial metabolism trade-offs, and potential interactions under varied environmental conditions.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"211 ","pages":"Article 109954"},"PeriodicalIF":10.3,"publicationDate":"2025-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144911225","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":"Controlled redox potentials and flooding duration affect microbial community composition and biomass in an arable soil","authors":"Felizitas Boie ,&nbsp;Sabry M. Shaheen ,&nbsp;Ellen Kandeler ,&nbsp;Jörg Rinklebe","doi":"10.1016/j.soilbio.2025.109962","DOIUrl":"10.1016/j.soilbio.2025.109962","url":null,"abstract":"<div><div>Redox conditions regulate biogeochemical cycling and microbial communities in soils. However, the extent to which redox potentials (E_H) affect microbial community composition remains unclear. This study elucidates the effects of controlled E_H on microbial biomass and on bacterial, fungal, and archaeal abundance.</div><div>An arable soil with stagnant properties was flooded and incubated under stable E_H at 100, 300, 400, and 550 mV (standardized to pH 7). Microbial community composition was investigated by phospholipid fatty acid (PLFA) analysis and quantitative polymerase chain reaction (qPCR) targeting 16S and 18S rRNA genes. Additionally, relevant electron acceptors (NO₃⁻, Mn, Fe, SO₄²⁻), organic carbon (C), nitrogen, and nutrients (P and S) were measured in the dissolved phase to link anaerobic respiration and nutrient availability with microbial community composition.</div><div>Microbial biomass and community composition were affected by E_H and flooding duration. Bacterial, fungal, and archaeal gene copy numbers were lowest at 100 mV and decreased with flooding duration. The microbial community composition differed between reducing and oxidizing redox conditions, especially between 100 and 400 mV. This change was associated with nitrification at ≥ 400 mV and lower energy net yields at 100 mV due to microbial Mn reduction compared to NO₃⁻ reduction or aerobic respiration. Electron acceptor and nutrient availability explained over 50 % of variation in microbial community composition.</div><div>We conclude that E_H and flood duration regulate microbial biomass, community composition, and respiration pathways in flooded soils primarily through their effects on electron acceptor and nutrient availability.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"211 ","pages":"Article 109962"},"PeriodicalIF":10.3,"publicationDate":"2025-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144911226","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 long road to soil health restoration: earthworms and soil structure show partial recovery in 18-year-old forest skid trails","authors":"Maximilian Behringer ,&nbsp;John Koestel ,&nbsp;Bart Muys ,&nbsp;Karin Wriessnig ,&nbsp;Markus Bieringer ,&nbsp;Matthias Schlögl ,&nbsp;Klaus Katzensteiner","doi":"10.1016/j.soilbio.2025.109953","DOIUrl":"10.1016/j.soilbio.2025.109953","url":null,"abstract":"<div><div>Compaction may impair soil health for decades. In a controlled experiment on clayey temperate forest soils, we assessed the effects of ground-based timber harvesting on earthworm abundance and soil structure. We compared freshly trafficked skid trails with those created 18 years ago at the same site. Earthworms were sampled in the ruts of the skid trails and in adjacent undisturbed plots. In addition, we collected undisturbed soil cores at 5 and 15 cm depths for X-ray imaging to assess soil structure.</div><div>We identified five earthworm species: <em>Aporrectodea rosea</em>, <em>Dendrobaena depressa</em>, <em>Dendrodrilus rubidus</em>, <em>Lumbricus rubellus</em>, and <em>Octolasion lacteum</em>. Earthworm abundance was highest on 18-year-old skid trails, particularly of endogeic and juvenile anecic individuals. The abundance of adult anecics remained reduced.</div><div>The X-ray data showed that imaged porosity declined sharply after trafficking (from 14.4 ± 5.0 % to 3.5 ± 1.6 % at 5 cm; and from 13.5 ± 4.9 % to 2.0 ± 1.1 % at 15 cm) but recovered at 5 cm within 18 years (12.2 ± 4.3 %), with only partial recovery at 15 cm (7.1 ± 2.5 %). Other structural parameters including biopores, pore anisotropy and Γ-connectivity (connectivity probability; dimensionless local connectivity measure, confined to the range [0,1]) and bulk density followed similar trends. However, the anisotropy of rock fragments did not recover. Pressure and shear forces during harvesting aligned the rock fragments horizontally.</div><div>Our data show that earthworms can recolonize compacted forest soils, but recovery of soil structure is depth-dependent and remains incomplete at 15 cm depth after 18 years, resulting in a highly biological active layer sitting on top of a hard pan.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"210 ","pages":"Article 109953"},"PeriodicalIF":10.3,"publicationDate":"2025-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144892152","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":"Exogenous carbon-to-nitrogen imbalance drives soil viral roles in microbial carbon mineralization and necromass accrual","authors":"Shuo Wang ,&nbsp;José Luis López Arcondo ,&nbsp;Ninghui Xie ,&nbsp;Yongfeng Wang ,&nbsp;Ying Zhang ,&nbsp;Mark Radosevich ,&nbsp;Bas E. Dutilh ,&nbsp;Xiaolong Liang","doi":"10.1016/j.soilbio.2025.109952","DOIUrl":"10.1016/j.soilbio.2025.109952","url":null,"abstract":"<div><div>Viruses are integral components of soil microbial community dynamics and carbon cycling, yet their roles in modulating organic matter (OM) transformations under varying nutrient conditions remain poorly understood. This study investigates how exogenous substrate treatment carbon-to-nitrogen (C/N) ratios influence soil viral communities and their roles in microbial activities and necromass carbon accrual in soils differing in physicochemical properties, including native OM contents. A 28-day incubation experiment was conducted using glucose and NH₄Cl amendments at C/N ratios of 5, 10, and 35 in soils from the Songnen and Liaohe Plains. Viromic analyses revealed that both soil properties and amendment C/N ratios significantly shaped viral diversity and composition. Notably, viral species richness and diversity were higher in LH-soils than in SN-soils and were significantly increased upon exogenous substrate addition in both soil types. In SN-soils, viral species richness declined with increasing amendment C/N ratios, coupled with shifts in viral lifestyle balances, underscoring the importance of nitrogen availability in virus-bacterial interactions. The relative abundance of temperate and virulent viruses exhibited distinct patterns associated with multiple soil properties, influencing microbial community interactions and necromass carbon accrual. Structural equation modeling (SEM) indicated divergent effects of viral communities on SOC accumulation across soils. In LH-soils, viral activity negatively associated with bacterial diversity and microbial necromass accumulation (using amino sugar biomarkers as proxies). In contrast, viral dynamics appeared to facilitate necromass incorporation into SOC in SN-soils, suggesting context-dependent viral influences on carbon sequestration. These findings highlight the critical yet nuanced roles of soil viruses in nutrient cycling and carbon storage, providing novel insights into viral ecological functions under varying nutrient and soil context conditions.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"210 ","pages":"Article 109952"},"PeriodicalIF":10.3,"publicationDate":"2025-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144886697","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}