European Journal of Soil Biology最新文献

{"title":"Faba bean-wheat intercropping controls the occurrence of faba bean Fusarium wilt by improving the microecological environment of rhizosphere soil","authors":"Yiran Zheng ,&nbsp;Jing Zhang ,&nbsp;Dongsheng Wang,&nbsp;Siyin Yang,&nbsp;Zixuan Cen,&nbsp;Yan Dong","doi":"10.1016/j.ejsobi.2024.103685","DOIUrl":"10.1016/j.ejsobi.2024.103685","url":null,"abstract":"<div><h3>Background</h3><div>Fusarium wilt is a severe soil-borne disease that affects faba bean production. Faba bean-wheat intercropping is often used to control the occurrence of Fusarium wilt in faba bean.</div></div><div><h3>Aims</h3><div>To evaluate the effects of faba bean-wheat intercropping on the occurrence of faba bean Fusarium wilt and soil microecology.</div></div><div><h3>Methods</h3><div>We established two planting patterns, faba bean monocropping (M) and faba bean-wheat intercropping (I), to investigate Fusarium wilt occurrence and plant dry weight and assess changes in soil enzyme activities, microbial diversity, and community composition during different stages of disease onset.</div></div><div><h3>Results</h3><div>Intercropping effectively controlled faba bean Fusarium wilt at the three disease stages and increased the dry weight of faba bean plants. Intercropping promoted the activities of catalase (CAT), urease, sucrase, and acid phosphatase in the rhizosphere soil of faba bean at three disease stages. Bacterial and fungal diversity decreased with disease progression, and intercropping mitigated this trend. Compared with monocropping, intercropping increased the abundance of beneficial bacteria such as Proteobacteria, Actinobacteriota, Gemmatimonadota, <em>Gemmatimonas</em>, <em>Conexibacter</em>, and <em>Sphingomonas</em>, while reducing the abundance of pathogenic fungi such as <em>Alternaria</em>, <em>Cladosporium</em>, and <em>Fusarium</em>. Intercropping also increased the abundance of arbuscular mycorrhiza, soil saprophytes, and undefined saprophytes while decreasing the abundance of plant pathogens.</div></div><div><h3>Conclusion</h3><div>Faba bean-wheat intercropping enhanced soil enzyme activities, effective nutrient content, and alpha diversity indices of bacteria and fungi in the rhizosphere soil of faba bean, while promoting the abundance of beneficial bacteria, arbuscular mycorrhizal fungi, as well as both soil and undefined humus. Simultaneously, intercropping reduced the abundance of plant pathogens, facilitated nutrient cycling in the soil, provided sufficient nutrients for crop uptake, and mitigated the toxic effects of hydrogen peroxide on cells. Ultimately, this resulted in a reduced occurrence of Fusarium wilt.</div></div>","PeriodicalId":12057,"journal":{"name":"European Journal of Soil Biology","volume":"123 ","pages":"Article 103685"},"PeriodicalIF":3.7,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142433042","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 microbial resistance and resilience to drought under organic and conventional farming","authors":"Elena Kost ,&nbsp;Dominika Kundel ,&nbsp;Rafaela Feola Conz ,&nbsp;Paul Mäder ,&nbsp;Hans-Martin Krause ,&nbsp;Johan Six ,&nbsp;Jochen Mayer ,&nbsp;Martin Hartmann","doi":"10.1016/j.ejsobi.2024.103690","DOIUrl":"10.1016/j.ejsobi.2024.103690","url":null,"abstract":"<div><div>The impacts of climate change, such as drought, can affect soil microbial communities. These communities are crucial for soil functioning and crop production. Organic and conventional cropping systems can promote distinct soil microbiomes and soil organic carbon contents, which might generate different capacities to mitigate drought effects on these cropping systems. A field-scale drought simulation was performed in long-term organically and conventionally managed cropping systems differing in fertilization and pesticide application. The soil microbiome was assessed during and after drought in bulk soil, rhizosphere, and roots of wheat. We found that drought reduced soil respiration and altered microbial community structures, affecting fungi in the bulk soil and rhizosphere more strongly than prokaryotes. Microbial communities associated with crops (i.e. rhizosphere and root) were more strongly influenced by drought compared to bulk soil communities. Drought legacy effects were observed in the bulk soil after harvesting and rewetting. The extent of the structural shifts in the soil microbiome in response to severe drought did not differ significantly between the organic and conventional cropping systems but each cropping system maintained a unique microbiome under drought. All cropping systems showed relative increases in potential plant growth-promoting genera under drought but some genera such as <em>Streptomyces</em>, <em>Rhizophagus, Actinomadura</em>, and <em>Aneurinibacillus</em> showed system-specific drought responses. This agricultural field study indicated that fungal communities might be less resistant to drought than prokaryotic communities in cropping systems and these effects get more pronounced in closer association with plants. Organic fertilization and the associated increase in soil organic carbon, or the reduction in pesticide application might not have the proposed ability to buffer severe drought stress on soil microbial taxonomic diversity. Yet, it remains to be elucidated whether the ability to maintain system-specific soil microbiomes also during drought translates into different functional capabilities to cope with the stress.</div></div>","PeriodicalId":12057,"journal":{"name":"European Journal of Soil Biology","volume":"123 ","pages":"Article 103690"},"PeriodicalIF":3.7,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142587210","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bacteria contribute more than fungi to SOC decomposition in a paddy field under long-term free-air CO2 enrichment","authors":"Meiling Xu ,&nbsp;Feifan Zhang ,&nbsp;Ling Zhang ,&nbsp;Hongze Zhang ,&nbsp;Caixian Tang ,&nbsp;Xiaozhi Wang ,&nbsp;Jing Ma ,&nbsp;Qiao Xu","doi":"10.1016/j.ejsobi.2024.103682","DOIUrl":"10.1016/j.ejsobi.2024.103682","url":null,"abstract":"<div><div>Microbial responses to future climate change are important in determining soil organic carbon cycling and evaluating carbon-climate feedback. Paddy soils from a 15-year free-air CO₂ enrichment (FACE) experiment were incubated and analyzed to reveal the responses of soil microbial activity, community diversity and composition to the soil depth and elevated CO₂. Network topology analysis was conducted to determine microbial complexity and stability, and Mantel tests were used to analyze the correlation between bacteria and fungi and soil respiration. Elevated CO₂ stimulated cumulative soil respiration (topsoil 6.2 %, subsoil 21.8 %), which was positively correlated with bacterial diversity. The elevated CO₂ effects on the microbial community were greater in the topsoil than in the subsoil, namely, bacterial diversity was increased by 2.1 % in the topsoil (0–15 cm). Elevated CO₂ also increased the abundance of Nitrospirota in the top- but not in the subsoil. Fungal diversity and phyla were not affected by elevated CO₂, but fungal diversity was significantly correlated with the contents of soil DOC, total dissolved N, and total P in the subsoil. Compared to the subsoil, bacterial richness was higher in topsoil, and more Ascomycota was found but fewer Mortierellomycota; the microbial network had a greater number of nodes and edges. These results suggested that 1) depth was a major factor affecting soil properties that determine microbial community and function; 2) bacterial taxa were more sensitive to elevated CO₂ than fungal taxa; 3) elevated CO₂ increased SOC decomposition directly via enhanced soil C availability and altered bacterial diversity and microbial complexity and stability.</div></div>","PeriodicalId":12057,"journal":{"name":"European Journal of Soil Biology","volume":"123 ","pages":"Article 103682"},"PeriodicalIF":3.7,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142420021","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":"Nutrient supply enhances positive priming of soil organic C under straw amendment and accelerates the incorporation of straw-derived C into organic C pool in paddy soils","authors":"Yuxuan Zhang ,&nbsp;Mengya Lu ,&nbsp;Zhiquan Wang ,&nbsp;Kun Zhang ,&nbsp;Bin Zhang ,&nbsp;Reziwanguli Naimaiti ,&nbsp;Shangyuan Wei ,&nbsp;Xueli Ding","doi":"10.1016/j.ejsobi.2024.103695","DOIUrl":"10.1016/j.ejsobi.2024.103695","url":null,"abstract":"<div><div>Straw return accelerates the decomposition of soil organic C (SOC), a phenomenon referred to as the priming effect. However, the interactive influence of nutrient supply levels on priming effect intensity and SOC sequestration in paddy soils still needs to be better understood. In this study, we investigated the dynamics of the priming effect and associated changes in phospholipid fatty acids, enzyme activity, and microbial necromass following the addition of ¹³C-labelled rice straw (98 % atom) to soils under three nutrient supply levels during a 300-d incubation period. Our results showed that the addition of straw (5 g C kg⁻¹ soil) with no-nutrient (S + Nu₀), low nutrient (S + Nu_low, 42 mg N kg⁻¹, 10 mg P kg⁻¹), and high nutrient (S + Nu_high, 126 mg N kg⁻¹, 30 mg P kg⁻¹) supply increased total CO₂ production by 42.9 %, 59.0 %, and 97.3 %, respectively, compared to the control soil. After 300 d, the cumulative priming effect was nearly doubled in the S + Nu_low and tripled in the S + Nu_high compared to the S + Nu₀. Moreover, the intensity of priming varied with the incubation stage under nutrient treatments. Similar patterns of priming effect were observed across all straw amendments during the early incubation stages; however, the priming effect increased with the nutrient supply levels in the later stages. These patterns are linked to microbial metabolic limitation and resource acquisition strategies, as evidenced by a lower C-to-N stoichiometry of extracellular enzymes and necromass in the S + Nu_low S + Nu_high. A greater proportion of straw-derived C incorporation into SOC (indicated by higher levels ¹³C-SOC) in nutrient-enriched was found, which largely offset the native SOC losses, resulting in high SOC content by the end of incubation. Our findings highlight the critical role of nutrient supply in regulating the priming effect and the balance of SOC after straw return in paddy soils.</div></div>","PeriodicalId":12057,"journal":{"name":"European Journal of Soil Biology","volume":"123 ","pages":"Article 103695"},"PeriodicalIF":3.7,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142652449","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":"Dynamics of nitrogen mineralization and nitrogen cycling functional genes in response to soil pore size distribution","authors":"Danni Li ,&nbsp;Yi Li ,&nbsp;Shuihong Yao ,&nbsp;Hu Zhou ,&nbsp;Shan Huang ,&nbsp;Xianlong Peng ,&nbsp;Yili Meng","doi":"10.1016/j.ejsobi.2024.103692","DOIUrl":"10.1016/j.ejsobi.2024.103692","url":null,"abstract":"<div><div>Soil pore distribution influences the permeability of gas, water, and solutes, affecting microbial activities such as nitrogen (N) mineralization. Understanding its impact on N mineralization and the subsequent N transformations is essential for managing compacted paddy soils. This study conducted incubation experiments on two paddy soils from typical Chinese rice regions, Northeastern meadow chernozemic Mollisols, and Southern umbric Ferralsols, under three bulk densities (1.0 g cm⁻³, 1.2 g cm⁻³, and 1.4 g cm⁻³) to investigate the effects of soil porosity on N mineralization and N cycling functional genes. Although the cumulative mineralized N showed no significant difference, with increased macropores (&gt;100 μm) and mesopores (30–100 μm), Ferralsols exhibited a significantly higher net N mineralization rate from day 0 to day 7, while Mollisols extended the mineralization after day 21. Soil dissolved organic carbon (DOC) had a similar temporal trend to the net N mineralization rate, suggesting DOC was the product of mineralization. Soil microbial biomass carbon (MBC) showed an opposite temporal trend to the net N mineralization rate in Mollisols, suggesting microbial biomass as a key N source for mineralization. Soil pores distribution did not affect nitrification under waterlogged conditions, but it affected <em>nirK</em>, <em>nirS</em> and <em>nosZ</em> genes by altering redox potential and substrates availability in the pore micro-environment. Overall, soil pores over 30 μm were the key pore size ranges affecting the intensity and duration of N mineralization, with different effects on DOC, MBC, and N cycling functional genes in Mollisols and Ferralsols. These findings emphasized the role of pore size in regulating N transformation in waterlogged conditions, contributing to the understanding of the N availability in compacted paddy soils from typical geographic rice-growing regions.</div></div>","PeriodicalId":12057,"journal":{"name":"European Journal of Soil Biology","volume":"123 ","pages":"Article 103692"},"PeriodicalIF":3.7,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142593465","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Planting Chinese milk vetch with phosphate-solubilizing bacteria inoculation enhances phosphorus turnover by altering the structure of the phoD-harboring bacteria community","authors":"Danna Chang ,&nbsp;Yarong Song ,&nbsp;Hai Liang ,&nbsp;Rui Liu ,&nbsp;Cheng Cai ,&nbsp;Shuailei Lv ,&nbsp;Yulin Liao ,&nbsp;Jun Nie ,&nbsp;Tingyu Duan ,&nbsp;Weidong Cao","doi":"10.1016/j.ejsobi.2024.103678","DOIUrl":"10.1016/j.ejsobi.2024.103678","url":null,"abstract":"<div><p>This study aimed to reveal how planting Chinese milk vetch (CMV) as green manure in combination with phosphate-solubilizing bacteria-based biofertilizer can enhance phosphorus (P) utilization in CMV-rice crop rotations. The pot experiment included two factors: the presence of <em>Acinetobacter calcoaceticus</em> (<em>ACC</em>) inoculation, and the variety of CMV (six varieties), resulting in 12 treatments. The experiment lasted for 190 d and soil and plants were analyzed thereafter. <em>ACC</em> inoculation increased the average shoot dry weight by 37.1 % and P uptake by 73.9 % of CMV, and increased the average content of soil labile P by 9.2 %; decreased the average content of moderately labile P by 6.9 % and stable P by 5.4 %, compared to control. <em>ACC</em> inoculation increased the average concentrations of acetic acid, gluconic acid, oxalic acid, citric acid, acid phosphatase and alkaline phosphatase. Structural equation model showed that organic acid and phosphatase correlated with soil labile and moderately labile P pools. The average abundance and diversity of the alkaline phosphatase gene (<em>phoD</em>) and the proportion of dominant species in the mineralization of organic P (<em>Streptomycetaceae</em>) increased under <em>ACC</em> inoculation. Thus, planting CMV with <em>ACC</em> inoculation increased the average concentrations of organic acid and alkaline phosphatase, activating insoluble inorganic P and organic P. However, their combination enhanced the average abundance and altered the structure of the <em>phoD</em>-harboring bacteria community, which in turn promoted organic P mineralization. Planting Chinese milk vetch with <em>Acinetobacter calcoaceticus</em> inoculation can effectively utilize P in paddy soil, which can enhance P availability for subsequent rice crops.</p></div>","PeriodicalId":12057,"journal":{"name":"European Journal of Soil Biology","volume":"123 ","pages":"Article 103678"},"PeriodicalIF":3.7,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142242167","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":"Fire alters soil bacterial and fungal communities and intensifies seasonal variation in subtropical forest ecosystem","authors":"Ziyue Shi ,&nbsp;Yaru Chen ,&nbsp;Aogui Li ,&nbsp;Mengjun Hu ,&nbsp;Weixing Liu","doi":"10.1016/j.ejsobi.2024.103677","DOIUrl":"10.1016/j.ejsobi.2024.103677","url":null,"abstract":"<div><p>Soil microbes stand as pivotal constituents and perform important ecological functions in forest ecosystems due to their extensive diversity. The increasing frequency of forest fire, coupled with the accelerating global warming, has resulted in changes in environmental conditions and forest structure, consequently influencing soil microbial communities. Despite this, there is a lack of comprehensive understanding regarding the impacts of fire on soil bacterial and fungal communities. Based on a fire experimental study in subtropical forest ecosystem, we investigated the alterations in soil properties and microbial community across two seasons. The results showed that soil bacterial richness remained unchanged by fire in both seasons. In contrast, soil fungal richness decreased in spring but increased in autumn at burnt sites, indicating the amplified seasonal variation induced by fire. In addition, fire had a significant impact on soil microbial community composition. Specifically, it elevated the relative abundance of Actinobacteriota but reduced that of Acidobacteriota and Verrucomicrobiota, which was related to increased temperature, pH, and decreased nitrogen resulting from fire. The relative abundance of Ascomycota increased following fire, whereas the relative abundance of Basidiomycota decreased. These shifts in soil fungal community were mainly related to lower soil carbon:nitrogen ratio. Furthermore, bacterial community was more responsive to environmental changes than fungal community. Overall, our study demonstrates soil microbial diversity and community structure in response to forest fire and the driving factors, advancing our comprehension of soil microbial dynamics in forest ecosystems under environmental perturbations.</p></div>","PeriodicalId":12057,"journal":{"name":"European Journal of Soil Biology","volume":"123 ","pages":"Article 103677"},"PeriodicalIF":3.7,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142242096","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":"In-depth insights into carbohydrate-active enzyme genes regarding the disparities in soil organic carbon after 12-year rotational cropping system field study","authors":"Hao Wang ,&nbsp;JinPing Chen ,&nbsp;Mingxue Du ,&nbsp;Yihao Ruan ,&nbsp;Jiameng Guo ,&nbsp;Ruixin Shao ,&nbsp;Yongchao Wang ,&nbsp;Qinghua Yang","doi":"10.1016/j.ejsobi.2024.103694","DOIUrl":"10.1016/j.ejsobi.2024.103694","url":null,"abstract":"<div><div>Carbohydrate-active enzymes (CAZymes) play a crucial role in plant-derived carbon utilization and decomposition and are influenced by the crop rotation system; however, our knowledge of how different agricultural systems impact CAZyme functionality is still limited. We conducted a metagenomic analysis to evaluate the functional genes of CAZymes in a 12-year in situ farmland with three commonly used crop rotation systems: wheat-maize rotation (WM), wheat-cotton rotation (WC), and wheat-soybean rotation (WS). We aimed to study the impact of long-term use of crop rotation, especially crop rotation involving soybean, on soil organic carbon (SOC) content and to gain an in-depth understanding of the CAZyme genes in context of the disparities in SOC. After 12 years, the SOC content was significantly higher in WS than in WC (5.44 %) and WM (17.6 %). Furthermore, the crop rotation system had a significant effect on the soil microbial communities and CAZyme function genes. Detailly, WS increased the phyla abundance of <em>Proteobacteria</em>, <em>Actinobacteria</em>, and <em>Firmicutes</em> and enriched the glycoside hydrolase (GH) and carbohydrate-binding modules (CBM) genes; WC increased the abundance of <em>Acidobacteria</em> and <em>Bacteroidota</em> and enriched the polysaccharide lyase gene; WM increased the abundance of <em>Nitrospirae</em>, <em>Candidatus_Rokubacteria</em>, <em>Chloroflexi</em> and <em>Gemmatimonadetes</em> and enriched the gene abundance of glycosyltransferases and auxiliary activity genes. Additionally, <em>Acidobacteria</em>, <em>Proteobacteria</em>, and <em>Actinobacteria</em> are key phyla involved in soil carbon cycling and collectively contribute &gt;70 % of the total CAZyme functional genes, which highlights their importance. In addition, our results indicated that total nitrogen content played a major role in influencing genes related to CAZymes, especially those belonging to the GH family. Our study demonstrates that WS conferred the advantage of increasing SOC across the three crop rotation systems. CAZyme analysis revealed that WS's could potentially support the increased abundance of <em>Proteobacteria</em>, <em>Actinobacteria</em> and <em>Firmicutes</em> in the soil community, at the same time potentially leading to increased number of GH and CBM genes in the soil, which may bolster the decomposition and transformation of plant-derived carbon, thus promoting an increase in SOC content. The findings of this study offer new insights into the microbial factors contributing to SOC enhancement in rotation systems.</div></div>","PeriodicalId":12057,"journal":{"name":"European Journal of Soil Biology","volume":"123 ","pages":"Article 103694"},"PeriodicalIF":3.7,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142652448","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":"Differences in succession of bacterial communities during co-cultivation of corn straw with different soils","authors":"Shuang Liu,&nbsp;Qingxin Meng,&nbsp;Yujia Li,&nbsp;Zhigang Wang,&nbsp;Weihui Xu,&nbsp;Yingning Sun,&nbsp;Zhidan Yu,&nbsp;Yunlong Hu","doi":"10.1016/j.ejsobi.2024.103683","DOIUrl":"10.1016/j.ejsobi.2024.103683","url":null,"abstract":"<div><div>Managing carbon inputs from straw can pave the way towards carbon neutrality and climate change mitigation. Straw decomposition by cooperative microbial actions is an important process of carbon cycling in nature, and in this process, microbial communities are constantly in succession. Soil is rich in microorganisms and can be a source of microbial for straw degradation. In this study, corn straw was mixed with different soil types and incubated in conical flasks for 70 days. Bacterial diversity and community structure were determined using 16S rRNA sequencing. Then, the effects of physicochemical parameters and enzyme activities on the composition of bacterial communities at different stages were evaluated. The results showed that bacterial diversity decreased during co-cultivation. The differences in bacterial communities between all treatments were greater in the later stages, with Pseudomonadota, Actinomycetota, and Bacillota as the major phyla. Among them, the biomarkers at different times for different treatments included <em>Sphingomonas</em>, <em>Mycobacterium</em>, <em>Oceanobacillus</em>, <em>Streptomyces</em>, <em>Pseudomonas</em>, <em>Flavobacterium</em>, and <em>Saccharomonospora</em>. All of them showed cellulose degradation capacity; thus, the organic matter gradually decreased during the co-cultivation. Canonical correspondence analysis (CCA) showed that pH, organic matter (OM), electrical conductivity (EC), cellulase, β-glucosidase, and filter paper (FPase) activities had a significant effect on bacterial communities at different stages. Our findings suggested that soil microbial communities can be an effective source of cellulose-degrading microorganisms, and corn straw co-cultivation with different soil types increased the abundance of cellulose-degrading bacteria, which provides the theoretical basis for efficient cellulose-degrading agent screening.</div></div>","PeriodicalId":12057,"journal":{"name":"European Journal of Soil Biology","volume":"123 ","pages":"Article 103683"},"PeriodicalIF":3.7,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142433043","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":"Coupling methane oxidation and N2 fixation under methanogenic conditions in contrasting environments","authors":"Yongliang Mo ,&nbsp;Jiwei Li ,&nbsp;Xiaotong Peng ,&nbsp;Adrian Ho ,&nbsp;Zhongjun Jia","doi":"10.1016/j.ejsobi.2024.103693","DOIUrl":"10.1016/j.ejsobi.2024.103693","url":null,"abstract":"<div><div>Microbial methane oxidation under widespread suboxic environment is crucial for understanding methane emission. However, the role of aerobic methanotrophs in mediating methane oxidation and nitrogen fixation is less understood in oxygen-limiting environments. In this study, we identified diazotrophic methanotrophs under oxygen-limited conditions (initial O₂ of 6–8 μM) in two contrasting habitats (paddy soil and marine sediment) using DNA-based stable isotope probing combined with amplicon sequencing. Consistently, we documented significant ¹³CH₄ oxidation and ¹⁵N₂ fixation after 740 days of suboxic isotope labeling. Sequencing analysis revealed the predominance of <em>Methylobacter</em>–affiliated aerobic methanotrophs in the ¹³C-labeled DNA fractions. These <em>Methylobacter</em>-like OTUs accounted for 97.86 % in paddy soil and 99.49 % in marine sediment of the total <em>pmoA</em> gene sequences; while relative abundances for the <em>nifH</em> gene sequences were 91.59 % in paddy soil and 99.49 % in marine sediment. Taken together, our analyses revealed that <em>Methylobacter</em> is responsible for methane oxidation and nitrogen fixation under oxygen limitation in both habitats, demonstrating convergent emergence of this aerobic methanotroph under oxygen deficiency.</div></div>","PeriodicalId":12057,"journal":{"name":"European Journal of Soil Biology","volume":"123 ","pages":"Article 103693"},"PeriodicalIF":3.7,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142705591","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}