European Journal of Soil Biology最新文献

{"title":"Impact of grassland management intensity on associations between bacterial, fungal and plant communities","authors":"Johanna Mayerhofer ,&nbsp;Franziska Richter ,&nbsp;Aaron Fox ,&nbsp;Franco Widmer ,&nbsp;Andreas Lüscher ,&nbsp;Valentin Klaus ,&nbsp;Martin Hartmann","doi":"10.1016/j.ejsobi.2025.103754","DOIUrl":"10.1016/j.ejsobi.2025.103754","url":null,"abstract":"<div><div>Understanding co-occurrences of different taxa is of both fundamental and applied relevance, for example, to understand ecosystem processes and to design monitoring programs for above- and belowground biodiversity. Plants and microorganisms form complex, interdependent relationships, which are exposed to and may be compromised by agricultural management. Here we assessed the effect of grassland management intensities on bacterial, fungal and plant communities and their associations. We further analyzed the potential of inferring information from taxa of one community on structural changes of the other communities with the aim of potentially enhancing the efficiency of biodiversity assessments by finding common indicator taxa. For that, bacterial, fungal and plant communities as well as environmental factors were assessed in 89 grassland sites of either extensive type (no fertilization, late and infrequent cuttings) or intensive type (fertilization, early and frequent cuttings) of management in the Swiss lowlands.</div><div>Bacterial, fungal and plant community structures as well as plant indicator values for soil nutrients and moisture differed between management types. Also, community homogeneity was significantly higher for all communities in the intensively managed grassland. For bacterial community structures, this was likely related to a smaller soil pH range in intensively managed grassland, while a lower fungal and plant richness may have caused more homogenous fungal and plant community structures in intensively managed grassland. Further, correlation strength among community structures dropped by 25–66 % from extensively to intensively managed grassland. Finally, indicator analysis suggested that future monitoring programs may use plant taxa to estimate expected effects on fungal communities and vice versa, but bacterial communities require additional assessment. Our results revealed a multifaceted and profound effect of management on bacterial, fungal and plant communities, which reinforces the conservation value of extensively managed grassland.</div></div>","PeriodicalId":12057,"journal":{"name":"European Journal of Soil Biology","volume":"126 ","pages":"Article 103754"},"PeriodicalIF":3.7,"publicationDate":"2025-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144581420","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tracking assimilation of microbial biomass, leaf litter and artificially created soil organic matter by soil fauna using multi-resource stable isotope labelling","authors":"Amelie Hauer ,&nbsp;Andrey Zuev ,&nbsp;Antonis Chatzinotas ,&nbsp;Stephanie Jurburg ,&nbsp;Steffen Kümmel ,&nbsp;Anton Potapov","doi":"10.1016/j.ejsobi.2025.103752","DOIUrl":"10.1016/j.ejsobi.2025.103752","url":null,"abstract":"<div><div>Understanding the resource utilization of soil invertebrates is essential for elucidating nutrient cycling and energy flow in terrestrial ecosystems. The soil environment offers a wide range of resources to its consumers, including microbes, soil organic matter (SOM), and plant litter. Soil invertebrates are small and cryptic, and typically rely on diverse arrays of basal resources, making the determination of its specific contributions to the diets of distinct animal groups challenging. This study investigated the carbon and nitrogen flows from different organic resources to soil meso- and macrofauna using stable isotope dual-labelling (¹³C and ¹⁵N) in an experimental temperate forest mesocosm over a one-month period. Studied resources included bacterial and fungal biomass, leaf litter and artificial mineral-associated organic matter ‘a-MaOM’ made of microbial necromass and vermiculite – a newly developed substrate produced in-house to experimentally mimic stabilized SOM. Our findings indicate that mesofauna incorporated the isotopic label from bacteria and fungi within three days after label introduction, demonstrating their role as primary microbial consumers in soil food webs and highlighting the importance of microbial biomass as nutrient sources for soil mesofauna. In contrast, macrofauna showed no detectable label uptake during the entire experimental period, suggesting either dietary preferences for other, unidentified resources or reflecting physiological factors such as lower metabolic turnover and slower assimilation of labelled materials. No detectable label was found in the studied invertebrate groups in the a-MaOM and litter treatments during the short experimental period, indicating that its consumption by soil fauna was negligible in comparison to microbial biomass. Beyond feeding ecology, our study introduces a methodological innovation by producing stable ¹³C- and ¹⁵N-labelled a-MaOM, offering a new tool for experimentally tracking stabilized SOM pathways in soil food webs while its bioavailability to soil organisms remains to be studied. Overall, our results reveal distinct feeding strategies among soil invertebrates, emphasizing the importance of mesofauna-microorganism interactions in soil nutrient cycling and the differentiated feeding modes of meso- and macrofauna in temperate forest ecosystems.</div></div>","PeriodicalId":12057,"journal":{"name":"European Journal of Soil Biology","volume":"126 ","pages":"Article 103752"},"PeriodicalIF":3.7,"publicationDate":"2025-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144570658","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluating DNA extraction methods for eDNA metabarcoding of soil invertebrate diversity","authors":"Rumakanta Sapkota ,&nbsp;Živilė Buivydaitė ,&nbsp;Mille Anna Lilja ,&nbsp;Lea Ellegaard-Jensen ,&nbsp;Anne Winding ,&nbsp;Paul Henning Krogh","doi":"10.1016/j.ejsobi.2025.103751","DOIUrl":"10.1016/j.ejsobi.2025.103751","url":null,"abstract":"<div><div>Metabarcoding of environmental DNA (eDNA) has been increasingly used in assessing soil biodiversity, primarily for microorganisms but also for invertebrates. Currently, conventional morphological identification (CMI) for detecting microarthropods and earthworms involves extracting them via heat treatment or hand-sorting from soil blocks, and subsequent morphological identification. To compare the soil fauna community composition assessment methods, we compared CMI, DNA metabarcoding of heat-extracted invertebrates (comDNA), and DNA extracted directly from soil (eDNA). For eDNA, two commercially available QIAGEN DNA extraction kits were further compared: DNeasy Powerlyzer PowerSoil kit (eDNA_PS), based on 0.25 g of soil, and DNeasy PowerMax soil kit (eDNA_PM), based on 10 g of soil. PowerMax captured higher richness, while PowerSoil captured diversity comparable to that of comDNA. In eDNA and comDNA samples, arthropods dominated the community composition, followed by annelids. Both eDNA and comDNA methods captured several overlapping species,; however, each method also detected unique ASVs. Interestingly, comDNA captured a higher abundance of several ASVs that were not detected in eDNA. Regardless of the methods used, the location of the soil sampled showed a significant effect on soil fauna community structure. Several species detected or shared in DNA-based methods were also shared with CMI, and a few collembolan species detected by eDNA were also correlated with the abundance data from CMI. Further, the community composition of collembolans varied between the comDNA and two eDNA (eDNA_PS, eDNA_PM) methods; however, more than one-third of the species were detected across all three methods. Our findings show the complementarity of eDNA and comDNA and support the integration of DNA-based methods in future soil fauna biodiversity assessment programs.</div></div>","PeriodicalId":12057,"journal":{"name":"European Journal of Soil Biology","volume":"126 ","pages":"Article 103751"},"PeriodicalIF":3.7,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144523515","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Combining effects of nitrogen fertilizer and biochar on soil N2O emissions and microbial community in a subtropical rapeseed-soybean rotation","authors":"Chi Zhang ,&nbsp;Zhibo Li ,&nbsp;Yulin Miao ,&nbsp;Xiaolin Liao","doi":"10.1016/j.ejsobi.2025.103750","DOIUrl":"10.1016/j.ejsobi.2025.103750","url":null,"abstract":"<div><div>Reducing nitrogen fertilizer application is a key strategy for mitigating soil N₂O emissions in agriculture. Biochar has great potential in reducing excessive fertilizer use. However, the interactive effects of biochar and nitrogen (N) fertilization on N₂O emissions are poorly understood. This study investigated how varying N fertilization (H: 100 %, M: 75 %, and L: 50 % of the conventional urea application rate) and biochar application rates (B0: 0 t ha⁻², B1: 15 t ha⁻², and B2: 60 t ha⁻²) affect N₂O emissions, microbial community, and the abundance of N₂O-related functional genes (<em>amoA</em>, <em>nirS</em>, <em>nirK</em>, and <em>nosZ</em>) in a subtropical oilseed rape (<em>Brassica napus</em> L.)-soybean (<em>Glycine max</em> (L.) Merrill) rotation system. Compared to control treatments (B0), biochar increased soil cumulative N₂O emissions by 55–61.5 % in the oilseed season and 200–245 % in the soybean season. Biochar also significantly increased microbial diversity and altered bacterial community composition, with notable shifts in the relative abundance of key phyla such as Bacillota, Bacteroidota, Armatimonadota, and Nitrospirota. These effects were more pronounced under higher biochar application, likely driven by increases in soil total carbon (TC), nitrogen (TN), and ammonium (NH₄⁺-N). Biochar increased the abundance of N₂O-related genes but had no significant effect on the (<em>nirS</em> + <em>nirK</em>)/<em>nosZ</em> ratio. Co-occurrence network analysis further revealed that biochar altered microbial interactions in a rate- and season-dependent manner, with high rate simplifying the network and potentially disrupting community stability, especially during the soybean season. In contrast, N fertilizer had limited effects on N₂O emissions, microbial diversity or community structure. Partial least squares path modeling (PLS-PM) suggested that biochar increased N₂O emissions primarily by enhancing soil TC, TN, pH, and denitrification process, while N fertilizer may affect N₂O emissions through nitrification. These findings highlight the need for optimized biochar and fertilizer management strategies and emphasize the importance of identifying N₂O production pathways and conducting long-term field studies to ensure the sustainable use of biochar in agriculture.</div></div>","PeriodicalId":12057,"journal":{"name":"European Journal of Soil Biology","volume":"126 ","pages":"Article 103750"},"PeriodicalIF":3.7,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144472179","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of the soil springtail Folsomia candida on the composition, function, and microbial network of root-associated microbes of host plant Sedum plumbizincicola","authors":"Shaobing Li ,&nbsp;Liming Pu ,&nbsp;Zinan Wang ,&nbsp;Siyao Liu ,&nbsp;Fang Liang ,&nbsp;Yuping Ma ,&nbsp;Mingyun Jia ,&nbsp;Zhu Li ,&nbsp;Xin Ke ,&nbsp;Longhua Wu","doi":"10.1016/j.ejsobi.2025.103748","DOIUrl":"10.1016/j.ejsobi.2025.103748","url":null,"abstract":"<div><div>Plant root-associated microorganisms play a major role in promoting plant growth and suppressing pathogenic bacteria. Soil animals in complex soil systems, and especially springtails, interact closely with plants and microorganisms by preying on microorganisms and feeding on roots. However, currently there is a lack of knowledge about how soil springtails modify microbes associated with plant roots. Here the bacterial and fungal communities in the rhizosphere and endosphere of <em>Sedum plumbizincicola</em> in the presence of a soil springtail were investigated. 16S rRNA and ITS gene sequencing were used together with assessments of microbial biomass and carbon source utilization in the rhizosphere. The presence of the springtail did not impact the overall diversity of the microbial community or its assembly processes but it did alter the abundance of specific microorganisms. The springtail influenced the relative abundance of the genus <em>Pseudomonas</em> and the class Nitrospira in the rhizosphere. Moreover, the springtail increased the biomass and carbon source utilization of rhizosphere microbes and influenced the abundance of nitrogen cycle genes. Co-occurrence network analysis revealed an increase in the average degree and total number of nodes and edges within the microbial network in the presence of the springtail, indicating heightened microbial interactions and a more stable network. The results indicate that the springtail regulated the ecological functions of plant root-associated microorganisms and highlight for the first time the role of soil springtails in regulating the microbial community and functions associated with plant roots.</div></div>","PeriodicalId":12057,"journal":{"name":"European Journal of Soil Biology","volume":"126 ","pages":"Article 103748"},"PeriodicalIF":3.7,"publicationDate":"2025-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144366465","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Soil depth affects bacterial, but not fungal community structure and assembly in Robinia pseudoacacia plantations","authors":"Long Lv ,&nbsp;Jingui Zhang ,&nbsp;Charles P.-A. Bourque ,&nbsp;Qian Xiang ,&nbsp;Jianjun Zhang ,&nbsp;Xianlong Yang ,&nbsp;Jianxiao Zhu ,&nbsp;Jingyong Ma","doi":"10.1016/j.ejsobi.2025.103747","DOIUrl":"10.1016/j.ejsobi.2025.103747","url":null,"abstract":"<div><div>Forest soil microbial communities play an important role in nutrient cycling and overall ecosystem functioning; however, their responses to variations in soil depth and forest age (chronosequence) remain insufficiently understood. Therefore, it is necessary to investigate how microbial community assembly varies across soil depths and forest ages to enhance our understanding of microbial diversity and its role in forest ecosystem functioning. In this study, we used 16S rRNA gene and ITS sequencing to characterize bacterial and fungal community traits in both topsoil (0–20 cm) and subsoil (70–100 cm) layers in <em>Robinia pseudoacacia</em> plantations ranging in age from 10 to 50 years old. The results revealed that soil depth significantly influenced bacterial diversity, whereas fungal diversity remained largely unaffected. Bacterial diversity was significantly higher in the topsoil compared to the subsoil (<em>P</em> &lt; 0.05), while fungal diversity did not differ significantly between the two soil layers (<em>P</em> &gt; 0.05). The composition of bacterial and fungal communities was significantly influenced by both soil depth and forest age. Community assembly processes for both groups were predominantly governed by deterministic factors, specifically homogeneous selection. However, with increasing forest age, β-nearest taxon index (βNTI) for bacterial communities significantly decreased in both soil layers, whereas βNTI for fungal communities increased in the topsoil. Soil carbon (C) composition, specifically soil organic C (SOC) and particulate organic C (POC), emerged as the main factors regulating variation in bacterial and fungal assembly processes across the chronosequence of <em>R. pseudoacacia</em> plantations. Network analysis revealed that bacterial network structures in the subsoil were more complex than those in the topsoil. Furthermore, our study highlights that SOC, POC, easily oxidizable organic C (EOC), and total nitrogen (TN) were identified as key environmental factors influencing microbial community composition, co-occurrence network patterns, and assembly processes across soil layers. Our study underscores the critical role of soil C composition in shaping forest soil microbial communities. This study provides empirical evidence that vertical heterogeneity in C availability mediates depth-dependent microbial assembly during forest succession, offering mechanistic insights into strategies for enhancing subsoil C sequestration in ecologically fragile areas.</div></div>","PeriodicalId":12057,"journal":{"name":"European Journal of Soil Biology","volume":"126 ","pages":"Article 103747"},"PeriodicalIF":3.7,"publicationDate":"2025-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144338935","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"From fire to soil: the role of prescribed burns in land snail communities for improve conservation","authors":"Meritxell Soler Brugués ,&nbsp;Vicenç Bros ,&nbsp;Santi Ramos ,&nbsp;Roger Puig-Gironès","doi":"10.1016/j.ejsobi.2025.103749","DOIUrl":"10.1016/j.ejsobi.2025.103749","url":null,"abstract":"<div><div>As climate change increases fire intensity and frequency, prescribed burns have become a key tool in ecosystem management. This study examines the effects of prescribed burning, burn frequency, and habitat heterogeneity on soil-dwelling snail communities in Mediterranean ecosystems, aiming to improve fire management to conserve biodiversity while reducing fire risks. Conducted in the Massís del Montgrí (NE Iberian Peninsula), 40 subplots with varying burn histories were sampled. Gastropods were surveyed through active searches for larger snails and soil samples for smaller ones. Vegetation cover, leaf litter, and organic matter content were also measured. Prescribed burns generally reduced snail abundance and richness, with unburnt control areas hosting more snails. Small species were more common in unburnt plots with higher tree cover and organic matter content, while larger species generally thrived in frequently burned areas with higher herbaceous cover. Burn frequency and vegetation cover were key factors shaping snail communities, highlighting the role of fire-driven microhabitat changes – particularly through their effects on organic matter availability – in shifting soil-dwelling snail assemblages. By identifying species-specific responses to fire, this study contributes to our understanding of how fire shapes soil biodiversity and offer insights for prescribed burn regime management. We advocate for context-dependent Integrated Fire Management strategies that balance fire recurrence and intensity with habitat recovery. Adaptive management approaches and ongoing interdisciplinary monitoring will be essential to optimizing fire practices for biodiversity conservation.</div></div>","PeriodicalId":12057,"journal":{"name":"European Journal of Soil Biology","volume":"126 ","pages":"Article 103749"},"PeriodicalIF":3.7,"publicationDate":"2025-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144321759","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Diazotrophic communities shift with organic fertilizer substitution and growth stages in tomato field soil","authors":"Chunmiao Lu ,&nbsp;Jiahui Luo ,&nbsp;Tianlong Sheng ,&nbsp;Yuebin Xie ,&nbsp;Yuchen Xian ,&nbsp;Yanqiong Jiang ,&nbsp;Xiangzhen Li ,&nbsp;Minjie Yao","doi":"10.1016/j.ejsobi.2025.103746","DOIUrl":"10.1016/j.ejsobi.2025.103746","url":null,"abstract":"<div><div>Applying organic fertilizers can improve soil quality, promote the growth of nitrogen-fixing bacteria, and reduce dependence on chemical fertilizers. Here we investigated the effects of different organic fertilization treatments (organic fertilizer substituting 20 %, 40 % or 60 % of chemical nitrogen fertilizer and increased organic fertilizers at the rate of 45, 90 and 135 t ha⁻¹) on soil diazotrophic communities at different growth stages (seedling, flowering, fruiting and maturity) of tomato. The results indicated that both organic fertilizer treatments and growth stages significantly affected the diversity and compositions of soil diazotrophic community, and organic fertilizer had a greater effect than growth stages. Compared to chemical fertilizer, the organic substitution overall increased the relative abundances of <em>Bradyrhizobium</em>, <em>Skermanella</em>, <em>Paenibacillus</em> and <em>Azospirillum</em>. Increased organic fertilizers raised the relative abundances of <em>Methylocaldum</em> and <em>Hyphomicrobium</em>. Organic substitution treatments increased the network complexity and microbial interactions of diazotrophic communities, but increased organic fertilizers reduced the alpha diversity and network complexity. Organic fertilizer affected the diazotrophic community structure and key taxa mainly through altering soil available nutrients and pH. The key diazotrophic genera varied at different growth stages. <em>Azospirilum</em> and <em>Skermanella</em> played an important role in diazotrophic community assembly in the flowering stage, additionally, <em>Sinorhizobium</em>, <em>Paenibacillus</em>, and <em>Zoogloea</em> were important in the fruiting stage. This study provided a deep understanding of the roles of organic fertilizer in regulating soil diazotrophic communities in tomato field.</div></div>","PeriodicalId":12057,"journal":{"name":"European Journal of Soil Biology","volume":"126 ","pages":"Article 103746"},"PeriodicalIF":3.7,"publicationDate":"2025-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144290447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Trophic niche variation in springtails across soil depth","authors":"Jing-Zhong Lu ,&nbsp;Melissa Jüds ,&nbsp;Linlin Zhong ,&nbsp;Johannes Lux ,&nbsp;Stefan Scheu ,&nbsp;Amandine Erktan","doi":"10.1016/j.ejsobi.2025.103745","DOIUrl":"10.1016/j.ejsobi.2025.103745","url":null,"abstract":"<div><div>Soil invertebrates move vertically through the soil to forage and avoid environmental stress. However, how their diet shifts with depth remains poorly understood, limiting our understanding of their trophic plasticity. Trophic consistency across depths could result from similar trophic niches existing at the microscale within different soil layers (the micro-scale feeding hypothesis). To test this, we conducted a microcosm experiment incubating springtails (<em>Ceratophysella denticulata</em>) in six separate forest soil layers (O_L, and O_F/H, and 0–3, 3–6, 6–9 and 9–12 cm depth of the mineral soil) and analysed changes in Collembola stable isotope ratios (¹³C/¹²C, ¹⁵N/¹⁴N). As expected, ¹³C/¹²C and ¹⁵N/¹⁴N ratios in litter and soil organic matter increased with depth, whereas ¹³C/¹²C ratios of Collembola did not significantly differ across layers suggesting consistent basal resource use supporting the micro-scale feeding hypothesis. By contrast, ¹⁵N/¹⁴N ratios of Collembola increased with depth, following the trend of organic matter from O_L to 0–3 cm soil, but not beyond. These results suggest that carbon and nitrogen nutrition of springtails is decoupled, and that the use of litter to calibrate ¹⁵N/¹⁴N values for estimating trophic positions of soil animals requires careful interpretation. Our results highlight the importance of soil depth as determinant of trophic positions of soil animals and point to principle differences in nitrogen resource acquisition between litter and soil in soil animal decomposers. Overall, the vertical structure of soils and a microscale view of trophic interactions needs closer attention to better understand niche differentiation and resource acquisition of soil animals.</div></div>","PeriodicalId":12057,"journal":{"name":"European Journal of Soil Biology","volume":"126 ","pages":"Article 103745"},"PeriodicalIF":3.7,"publicationDate":"2025-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144289021","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Substitution of organic fertilizer did not change the dominant role of biochar on bacterial community stability but the soil carbon fractions","authors":"Husen Qiu ,&nbsp;Jieyun Liu ,&nbsp;Tida Ge","doi":"10.1016/j.ejsobi.2025.103744","DOIUrl":"10.1016/j.ejsobi.2025.103744","url":null,"abstract":"<div><div>Biochar and organic fertilizers are used to improve soil carbon retention. However, the interactive roles of biochar and organic fertilizer in stabilizing soil organic carbon (SOC) at different horizons remain unclear. A field experiment with biochar application (0 %, 1 %, and 2 % of dry soil; Control, LB, and HB, respectively) and organic fertilizer substitution (0 %, 20 %, 40 %, and 60 % of inorganic N; T0, T2, T4, and T6, respectively) (fermented sheep manure replacing urea-N)) was conducted to reveal the mechanisms. The SOC, particulate organic carbon (POC), and mineral-associated organic carbon (MAOC) contents increased with the biochar addition and organic fertilizer substitution. In the topsoil (0–15 cm), values ranged from 17 to 24 g kg⁻¹ (SOC), 2.03–6.6 g kg⁻¹ (POC), and 15–19 g kg⁻¹ (MAOC). In the subsoil (16–30 cm), the ranges were 16–20 g kg⁻¹ (SOC), 1.2–3.4 g kg⁻¹ (POC), and 14–18 g kg⁻¹ (MAOC). HB combined with organic fertilizer substitution promoted SOC, POC, and MAOC more effectively than biochar alone. The β-1,4-glucosidase and cellobiohydrolase (CBH) activities in the topsoil were 1.2–1.6 times higher than those in the subsoil. Increases in biochar reduced the POC/MAOC ratio by limiting CBH activity (P &lt; 0.05). Substituting organic fertilizer increased the POC/MAOC ratio by alleviating the limitation of biochar on bacterial biomass in the soil horizons. Bacterial community composition varied significantly with biochar addition and between soil horizons (P &lt; 0.05). Biochar enhanced the dominant role of heterogeneous selection and increased bacterial network complexity in both the topsoil and subsoil. Based on structural equation modeling, an increase in bacterial negative/positive cohesion significantly improved the proportion of MAOC in the topsoil (P &lt; 0.05). This study provides evidence that biochar (but not organic fertilizer substitution) helped improve C storage by decreasing the CBH activity and bacterial biomass, and enhancing network complexity. Thus, it is essential to consider soil horizons when evaluating the dynamic effects of agricultural practices on SOC pools.</div></div>","PeriodicalId":12057,"journal":{"name":"European Journal of Soil Biology","volume":"126 ","pages":"Article 103744"},"PeriodicalIF":3.7,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144239503","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}