Corey A. Palmer , David A. Orwig , Cameron D. McIntire , Ashley D. Keiser
{"title":"Decomposer functional breadth maintains litter decomposition patterns three decades after Eastern Hemlock decline","authors":"Corey A. Palmer , David A. Orwig , Cameron D. McIntire , Ashley D. Keiser","doi":"10.1016/j.soilbio.2025.109943","DOIUrl":"10.1016/j.soilbio.2025.109943","url":null,"abstract":"<div><div>Soil microbial communities, key drivers of decomposition and carbon cycling, can retain historical legacies whereby past environmental conditions, such as litter inputs or climate, shape contemporary function. The decline of eastern hemlock (<em>Tsuga canadensis</em>) due to the invasive hemlock woolly adelgid (HWA) is shifting North American forests toward birch-dominated stands, potentially imprinting a functional legacy on soil carbon cycling. However, due to the gradual nature of hemlock decline, it remains unclear whether this legacy persists over time, and if so, for how long. To test for an HWA-induced legacy effect, we measured litter decomposition and soil carbon and nitrogen pools across a chronosequence of six sites within the CT River valley (Connecticut and Massachusetts, USA). The sites span the northward spread of HWA ranging from 1987 infection in Southern Connecticut to 2020 infection in northern Massachusetts. We found no significant differences in litter mass loss across sites or litter types, suggesting that the functional breadth of soil microbial communities in hemlock forests persists even after hemlock mortality. Latitude was a strong predictor of soil labile carbon and nitrogen cycling, with higher values observed at lower latitudes where tree species richness was also greater. These findings indicate that legacy hemlock soils maintain microbial functional breadth for at least three decades following HWA invasion, sustaining decomposition and nutrient cycling during stand transition. Our results highlight the role of fine-scale microbially driven processes in mediating forest ecosystem responses to invasive pests, and suggests that microbial functional legacies may buffer ecosystem shifts following tree mortality.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"210 ","pages":"Article 109943"},"PeriodicalIF":10.3,"publicationDate":"2025-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144802902","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}
Keren Yanuka-Golub, Elisa Korenblum, Emma L. Aronson, Maor Matzrafi
{"title":"Linking microbial-mediated methane production in wetlands to invasive plants","authors":"Keren Yanuka-Golub, Elisa Korenblum, Emma L. Aronson, Maor Matzrafi","doi":"10.1016/j.soilbio.2025.109944","DOIUrl":"https://doi.org/10.1016/j.soilbio.2025.109944","url":null,"abstract":"Plant invasion has risen in recent decades due to climate change and land-use alterations, profoundly impacting biodiversity and ecosystem functioning. Belowground, invasive plants disrupt native microbial networks, altering nutrient cycling and soil organic matter dynamics. In wetlands, such disruptions can enhance methane (CH<sub>4</sub>) fluxes by reshaping both production and oxidation processes. Methanogenic archaea (methanogens) are the primary producers of biogenic CH<sub>4</sub>, but they differ in metabolic strategies (acetoclastic, hydrogenotrophic, or methylotrophic methanogenesis), depending on available substrates and environmental conditions. This review explores how invasive plants influence CH<sub>4</sub> emissions through changes in plant–soil feedbacks (PSFs), root exudation, microbial community composition, and methanogenic pathways. Invasive plants often restructure soil microbial communities by releasing species-specific metabolites, enhancing labile carbon inputs, and modifying rhizosphere conditions that favor methanogens. These shifts can elevate CH<sub>4</sub> emissions; however, the effects are highly context-dependent, some invasions lead to increased emissions, others show negligible change, and some even reduce CH<sub>4</sub> fluxes. In addition, the formation of aerenchyma in invasive wetland plants may bypass the methane filter formed by surface-dwelling methanotrophs, thus leading to higher net CH<sub>4</sub> emissions even if production remains unchanged. These variable outcomes depend on plant traits, microbial selection, soil hydrology, and interactions with climate-driven stressors. We propose that invasive plants, microbial communities, and climate change form a self-reinforcing PSF triangle that can amplify CH<sub>4</sub> emissions. Understanding the mechanisms behind these dynamics, including root exudate-driven microbial colonization and rhizosphere priming, could support predicting climate impacts of biological invasions in wetland ecosystems.","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"31 1","pages":""},"PeriodicalIF":9.7,"publicationDate":"2025-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144787465","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}
Xiaodong Sun, Chenyang Zhang, Kailou Liu, Minggang Xu, Andong Cai
{"title":"Long-term manure application enhances carbon use efficiency in soil aggregates by regulating microbial communities in cropland","authors":"Xiaodong Sun, Chenyang Zhang, Kailou Liu, Minggang Xu, Andong Cai","doi":"10.1016/j.soilbio.2025.109945","DOIUrl":"https://doi.org/10.1016/j.soilbio.2025.109945","url":null,"abstract":"Microbial carbon use efficiency (CUE), a key metric reflecting the allocation of carbon between microbial growth and respiration, plays a central role in predicting soil carbon (C) dynamics. Microbial CUE is influenced by soil aggregates that create nutrient heterogeneity, and long-term fertilization may alter these heterogeneous microsites. However, the effects of long-term fertilization on microbial CUE across different aggregates remain unclear, limiting mechanistic understanding of soil C cycling at the microscale. Here, a 34-year field experiment was conducted with five treatments including no fertilizer (CT), mineral nitrogen (N), mineral N, phosphorus and potassium (NPK), manure-only (M), and combined mineral fertilizer and manure (NPKM). Microbial CUE was measured in bulk soil and in >2 mm, 0.25–2 mm, and <0.25 mm aggregates using an <sup>18</sup>O-H<sub>2</sub>O labeling approach. Metagenomic sequencing, enzyme activity assays, and substrate analyses were integrated to examine how fertilization altered interactions among aggregates, substrate quality, and microbial communities affecting CUE. Results showed that, compared to CT, manure application (M and NPKM) significantly increased microbial CUE both in bulk soil and aggregates. While microbial activity and CUE differed among aggregates under CT and NPK, manure application homogenized CUE across aggregates. Further analysis revealed that manure application regulated enzyme activities and substrate quality, which affected key bacterial modules (M11 and M14) and consequently modulated microbial CUE. These findings underscore the role of manure in enhancing microbial CUE and suggest that accounting for manure-induced microscale homogenization can improve predictions of SOC dynamics in global C models.","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"27 1","pages":""},"PeriodicalIF":9.7,"publicationDate":"2025-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144787519","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}
Xiu Liu , Sheng Tang , Congyue Tou , Ji Chen , Wolfgang Wanek , Yakov Kuzyakov , David R. Chadwick , Davey L. Jones , Lianghuan Wu , Qingxu Ma
{"title":"Opposite roles of plant quality and soil exoenzymes in regulation of litter carbon transfer to fungal and bacterial necromass","authors":"Xiu Liu , Sheng Tang , Congyue Tou , Ji Chen , Wolfgang Wanek , Yakov Kuzyakov , David R. Chadwick , Davey L. Jones , Lianghuan Wu , Qingxu Ma","doi":"10.1016/j.soilbio.2025.109940","DOIUrl":"10.1016/j.soilbio.2025.109940","url":null,"abstract":"<div><div>Plant litter is a primary source of soil organic matter (SOM) through microbial transformation, with its quality, especially the hemicellulose and lignin content, strongly influencing litter decomposition and carbon (C) cycling. However, how the hemicellulose:lignin ratio regulates litter decomposition, transformation, and contribution to SOM remains unclear. Here, <sup>13</sup>C-labelled litter (hemicellulose:lignin ratios of 0.42–1.02) from six maize plant parts was used to trace <sup>13</sup>C incorporation into dissolved organic <sup>13</sup>C (DO<sup>13</sup>C), microbial biomass <sup>13</sup>C (MB<sup>13</sup>C), particulate organic <sup>13</sup>C (PO<sup>13</sup>C), mineral-associated organic <sup>13</sup>C (MAO<sup>13</sup>C), and <sup>13</sup>C-microbial necromass during an 84-day incubation. After 84 days, 11–18 % of litter decomposed to CO<sub>2</sub>, with fast decomposition at high hemicellulose:lignin ratios. Most litter C (9.1–16 %) was incorporated into MAO<sup>13</sup>C, followed by MB<sup>13</sup>C, PO<sup>13</sup>C, and DO<sup>13</sup>C. High hemicellulose:lignin ratios reduced microbial C use efficiency (CUE), indicating microbes prioritized energy utilization from hemicellulose-rich, labile substrates. Lower CUE led to greater MAOC accumulation within 84-day incubation. Increased <sup>13</sup>C-fungal necromass at a higher hemicellulose:lignin ratio suggests that labile C-rich litter supports new C sequestration, as fungal necromass is more stable than bacterial. <sup>13</sup>C-microbial necromass accounted for 22–38 % of MAO<sup>13</sup>C, suggesting that a large fraction of litter C was directly incorporated into MAOC without microbial transformation during the 84-day incubation period. Bacterial necromass formation was regulated by C-degradation enzyme activity, while fungal necromass was governed by litter quality. These findings highlight the role of litter quality and C-degradation enzyme activities in forming newly sequestered C by regulating C incorporation into microbial necromass, emphasizing labile litter component importance in soil C sequestration.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"210 ","pages":"Article 109940"},"PeriodicalIF":10.3,"publicationDate":"2025-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144779338","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":"Adaptive strategies of soil viruses in oligotrophic arid environments","authors":"Li Bi , Bin Ma , Ji-Zheng He , Hang-Wei Hu","doi":"10.1016/j.soilbio.2025.109941","DOIUrl":"10.1016/j.soilbio.2025.109941","url":null,"abstract":"<div><div>In natural environments, viruses must adapt to changing conditions such as variations in nutrient and water availability. However, our understanding of viral adaptation to different soil conditions remains limited. We compared soil viral adaptations in nutrient-limited arid inland regions versus nutrient-rich humid coastal regions using viromics. Our results provide new evidence that viruses employed diverse strategies to persist in oligotrophic arid environments. These strategies include (i) a higher prevalence of potential lysogenic viruses; (ii) a broader host range to enhance infection chances; (iii) encoding specific auxiliary metabolic genes to enhance viral fitness by boosting host resilience against nutrient limitation and aridity; and (iv) maintaining higher micro-diversity and more genes under positive selection to improve viral responses to inhospitable conditions.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"210 ","pages":"Article 109941"},"PeriodicalIF":10.3,"publicationDate":"2025-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144779339","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":"Dose-response patterns of anaerobic oxidation of methane to nitrogen addition in Chinese paddy fields","authors":"Wang-ting Yang, Qi-nan Hu, Si-le Wen, Bing-jie Ren, Evgenios Agathokleous, Li-dong Shen, Wei-qi Wang","doi":"10.1016/j.soilbio.2025.109942","DOIUrl":"https://doi.org/10.1016/j.soilbio.2025.109942","url":null,"abstract":"Anaerobic oxidation of methane (AOM) has been identified as a previously overlooked methane sink in paddy fields, and it is known to be stimulated by nitrogen inputs. However, important knowledge gaps remain regarding the response patterns of AOM potential to different levels of nitrogen addition, as well as the optimal nitrogen levels that maximize AOM. Here, we investigated AOM potential across six Chinese paddy fields under NaNO<sub>3</sub> additions of 0-200 mg N kg<sup>-1</sup> (with increments of 40 mg N kg<sup>-1</sup>). The AOM potential quantified by <sup>13</sup>CH<sub>4</sub> isotopic experiments was observed to increase linearly with nitrogen input, peaking at 120-160 mg N kg<sup>-1</sup>, after which the stimulatory effect plateaued or declined. AOM potential responses differed among sampling sites, and sites characterized by lower background available nitrogen levels or higher conductivity were more responsive to nitrogen addition. Furthermore, high-throughput sequencing and principal coordinates analysis revealed that the community composition of ANME-2d archaea played a more prominent role than that of NC10 bacteria in modulating AOM responses to nitrogen addition. Overall, this study revealed the dose-dependent stimulation of AOM potential by nitrogen addition in different Chinese paddy soils, highlighting the critical roles of soil inorganic nitrogen availability, conductivity, and the ANME-2d archaeal community in shaping AOM responses.","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"6 1","pages":""},"PeriodicalIF":9.7,"publicationDate":"2025-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144787660","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}
Gang Huang, Yan-gui Su, Si-nuo Lin, Zheng-yi Huang, Jin-yi Yan, Xiao-han Dai
{"title":"Microbial recalcitrant-C metabolism and community composition shifts support enhanced thermal adaptation of soil microbial respiration","authors":"Gang Huang, Yan-gui Su, Si-nuo Lin, Zheng-yi Huang, Jin-yi Yan, Xiao-han Dai","doi":"10.1016/j.soilbio.2025.109939","DOIUrl":"10.1016/j.soilbio.2025.109939","url":null,"abstract":"<div><div>Understanding microbial thermal responses along natural climate gradients is crucial for improving predictions of carbon-climate feedbacks. However, the mechanisms by which variations in microbial carbon metabolic strategies and community composition modulate thermal responses of microbial respiration remain poorly understood. Here, we investigated thermal responses of microbial respiration along an elevational temperature gradient with and without glucose addition, focusing on the roles of microbial carbon metabolic strategies and community composition in shaping microbial thermal responses. Our results revealed that microbial respiration exhibited enhanced adaptation to increasing mean annual temperature (MAT) of the sampling sites, and glucose addition further promoted the magnitude of enhanced thermal adaptation in both surface and subsurface soils. This pattern suggests a positive feedback of microbial carbon decomposition to warming. Metabolism of recalcitrant carbon compounds and enzymatic activities related to recalcitrant carbon oxidation increased with MAT, explaining the largest variation in the enhancement magnitude of microbial respiration. These specific microbial carbon metabolic strategies were linked to microbial carbon availability and shifts in microbial community structure toward oligotrophic microbial strategies. Overall, enhanced thermal adaptation of microbial respiration was associated with increased decomposition of recalcitrant carbon, driven by elevated enzymatic oxidation activity and a microbial community shift toward higher oligotrophic strategists, potentially alleviating microbial substrate limitations. Our findings highlight a mechanism whereby altered microbial carbon metabolic strategies may amplify soil carbon loss by mitigating substrate limitations under warming conditions.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"210 ","pages":"Article 109939"},"PeriodicalIF":10.3,"publicationDate":"2025-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144779340","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":"Applicability of live-fluorescence in situ hybridization (Live-FISH) on soil microbiomes","authors":"Iuliana Nita, Meriel J. Bittner, Yannick Buijs, Arnaud Dechesne, Mikkel Bentzon-Tilia","doi":"10.1016/j.soilbio.2025.109938","DOIUrl":"10.1016/j.soilbio.2025.109938","url":null,"abstract":"<div><div>Soil microbiomes play pivotal roles in ecosystem functioning and have been a trove of commercially important enzymes and drug leads. In recent years, metagenomic scrutiny has exposed the immense taxonomic and functional diversity of these microbiomes, leading to the realization that most microorganisms remain out of reach by conventional cultivation approaches. Live-Fluorescence <em>in situ</em> Hybridization (Live-FISH) coupled with fluorescence activated cell sorting represents a potential strategy to overcome cultivation barriers by enabling the taxa-specific extraction of viable cells for targeted cultivation efforts. However, it remains unknown to what extent this approach is applicable on soil microbiomes. Here, we evaluated the impact of Live-FISH on the viability of microorganisms extracted from temperate topsoil. Using propidium monoazide (PMA) viability qPCR, we observed a one-order of magnitude reduction in the number of viable cells as a result of the treatment. Through PMA viability sequencing, we observed an overall reduction in viable taxa as function of treatment, yet, 501 ASVs retained their viability and could serve as targets for future cultivation efforts. The effects proved to be taxon-specific, and we observed that the viability of Bacillota and Planctomycetota was retained to a larger extent than that of other dominant phyla like Acidobacteriota, which were reduced by five orders of magnitude throughout the steps of the procedure. Furthermore, planctomycetes were amenable to labelling and distinguishable in subsequent microscopy and flow cytometry analyses, demonstrating the utility of this technique to selectively label and extract viable species of this elusive phylum.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"210 ","pages":"Article 109938"},"PeriodicalIF":10.3,"publicationDate":"2025-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144766716","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}
Pengpeng Duan , Chaoqun Wang , Wolfgang Wanek , Xinyi Yang , Peilei Hu , Kelin Wang , Dejun Li
{"title":"Soil microbial phosphorus limitation constrains carbon use efficiency in subtropical forests","authors":"Pengpeng Duan , Chaoqun Wang , Wolfgang Wanek , Xinyi Yang , Peilei Hu , Kelin Wang , Dejun Li","doi":"10.1016/j.soilbio.2025.109937","DOIUrl":"10.1016/j.soilbio.2025.109937","url":null,"abstract":"<div><div>Microbial carbon use efficiency (CUE) is a vital parameter that determines soil's ability to sequester organic C, yet the response of CUE to land use intensification and the underlying mechanisms remain poorly understood, leading to large uncertainties in developing strategies to mitigate soil C losses. We investigated how legacies of land use (cropland and forest) intensity and climate affect microbial CUE along a subtropical climate gradient in southwest China. Our findings showed that microbial utilization of organic C for growth and C losses through respiration varied proportionally between land–use types, resulting in similar CUE values. However, microbial CUE was more sensitive to climate in managed ecosystems, being higher in cropland soils than in forest soils under warmer and wetter climate conditions. This indicates that intensive land use management increases the sensitivity of microbial CUE to climate change. In forest soils, CUE was constrained by low phosphorus (P) availability and was enhanced after P addition, whereas CUE in cropland soils showed no response, indicating that chronic P limitation is a key regulator of microbial metabolism in forests but not in adjacent croplands. Collectively, our work suggests that land use conversion does not necessarily alter microbial CUE, and highlights the importance of microbial P limitation in regulating and predicting forest soil organic C dynamics, particularly against the background of increasing P limitation induced by global changes such as nitrogen deposition and warming.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"210 ","pages":"Article 109937"},"PeriodicalIF":10.3,"publicationDate":"2025-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144766896","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}
Dasiel Obregon, Elizabeth Haack, Micaela Tosi, Ken Hahn, Irene Montero, Kari Dunfield
{"title":"Brine-induced soil gradients drive microbial community assembly and ecological partitioning","authors":"Dasiel Obregon, Elizabeth Haack, Micaela Tosi, Ken Hahn, Irene Montero, Kari Dunfield","doi":"10.1016/j.soilbio.2025.109936","DOIUrl":"https://doi.org/10.1016/j.soilbio.2025.109936","url":null,"abstract":"Brine (produced water) releases from oil and gas infrastructure alter soil physicochemical properties, disrupt vegetation, and affect microbial communities vital for soil function. We evaluated long-term brine disturbance effects on soil microbiota at a 25-hectare boreal site in northern Alberta, Canada. Soils, including both topsoil (A horizon) and subsoil (B horizon) layers, were sampled along four 300 m transects spanning undisturbed forest to brine-impacted areas. Soil gradients intensified toward brine-impacted zones, with electrical conductivity (EC) increasing from 0.1 to 40 dS m<sup>-1</sup>, sodium adsorption ratio (SAR) from 0.1 to 41, and pH from 4 to 8. Microbial diversity declined with rising EC, SAR, and pH, however, even in very strongly saline soils (EC > 16 dS m<sup>-1</sup>), Shannon diversity indices remained above 7. Approximately one-third of the microbial genera shifted in abundance along these gradients, with salinity-adapted taxa enriched and key oligotrophic groups declining. We identified tipping points in salinity, sodicity, and pH gradients—at EC 1.9 and 4.2 dS m<sup>-1</sup>, SAR 3.5 and 6.4, and pH ∼5.5—coinciding with major shifts in community composition. Habitat partitioning was evident, with 27% and 39% of taxa specialized to unimpacted and brine-impacted soils, respectively, while 20% were generalists. Network analysis revealed denser community assembly but reduced robustness in brine-impacted soils, indicating greater vulnerability to environmental perturbations. These findings highlight how soil microbiota reflect both the detrimental effects of brine disturbance and adaptive responses, underscoring their value as bioindicators for soil health assessment in salt-impacted landscapes.","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"14 1","pages":""},"PeriodicalIF":9.7,"publicationDate":"2025-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144747900","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}