Soil Biology & Biochemistry最新文献

{"title":"Controlling matric potential in microfluidics to examine microbial dynamics in unsaturated porous media","authors":"Shane M. Franklin ,&nbsp;Scott T. Retterer ,&nbsp;Amber N. Bible ,&nbsp;Jennifer L. Morrell-Falvey","doi":"10.1016/j.soilbio.2025.109916","DOIUrl":"10.1016/j.soilbio.2025.109916","url":null,"abstract":"<div><div>The use of microfluidics for the study of soil microbial ecology is an emerging field. Most microfluidic studies of biological systems, however, have been performed under fully saturated conditions that are not representative of natural soil. Therefore, while microfluidics offer many unique capabilities that other methodologies cannot, they are not currently suited to address the effects of matric potential, an important variable defining the microbial moisture niche. Here, a methodology is presented that allows the user to control the aqueous conditions within microfluidic networks by manipulating matric potential using a hanging water column. The method relies on hydrophilic surface treatment of the microfluidic device using polyvinyl alcohol (PVA) and incorporating a bed of small pores at the network boundaries, which serve as a porous ceramic plate analogue (PPA). The method was validated on a simple capillary bundle and then on a more complex pore network. A water retention curve, exhibiting hysteresis, was generated for the pore network over a narrow matric potential range of 0 to – 5 kPa. Both the drainage and wetting curves were reproducible, as were the spatial configuration and the number of fragmented moisture niches in the pore network, particularly on the drainage curve. In contrast, the wetting curve exhibited greater variability in spatial configuration due to the “ink bottle effect,” where capillarity was interrupted by wider pore bodies. Ultimately, the methodology provides realistic pore-scale moisture conditions that can be easily manipulated and maintained, enabling new opportunities to explore soil biophysics and microbial biogeography in unsaturated porous media. As a brief example, images showing the localization of fluorescently tagged <em>Pantoea</em> sp. YR343 at −4.3 kPa are presented, highlighting bacterial distributions in water films and air-water interfaces.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"210 ","pages":"Article 109916"},"PeriodicalIF":9.8,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144629962","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":"Nitrogen fertilisation of boreal forest soil increases soil carbon pool through elevated microbial necromass formation but also modifies tree secondary metabolism","authors":"Bartosz Adamczyk ,&nbsp;Sylwia Adamczyk ,&nbsp;Boris Tupek ,&nbsp;Qian Li ,&nbsp;Tijana Martinovic ,&nbsp;Etienne Richy ,&nbsp;Aleksi Lehtonen ,&nbsp;Petr Baldrian ,&nbsp;Raisa Mäkipää","doi":"10.1016/j.soilbio.2025.109917","DOIUrl":"10.1016/j.soilbio.2025.109917","url":null,"abstract":"<div><div>Forests contain significant amounts of the global carbon (C) pool with the major fraction stored belowground. Nitrogen (N) fertilisation of forest soils may increase biomass production and soil organic C pools, providing a strategy for climate change mitigation.</div><div>Here we aimed to elucidate the mechanisms behind the increase in soil C due to N addition using a long–term fertilisation experiment on a Scots pine stand with a combination of chemistry, microbiology and greenhouse gas fluxes.</div><div>Our results showed that N fertilisation increased C stocks, microbial biomass, necromass and the activity of extracellular enzymes, with no significant increase in greenhouse gas production. Moreover, N fertilisation decreased the production of a group of plant secondary metabolites, tannins. These profound changes were observed in the organic layer of the soil, and differences in mineral soil were less detectable.</div><div>Mechanistically, N fertilisation increased the C stock via elevated litter input and higher transfer of root C to soil microorganisms increasing fungal biomass and further necromass, which was stabilised in the soil. Our study supports the view that management strategies to increase microbial necromass in persistent C pools could lead to elevated C stabilization, though caution should be taken regarding potential changes in plant metabolism.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"209 ","pages":"Article 109917"},"PeriodicalIF":9.8,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144629960","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":"Diverging soil peroxidase activity under ectomycorrhizal versus arbuscular mycorrhizal conifers with increasing C:N and exchangeable manganese","authors":"J. Marty Kranabetter ,&nbsp;Freya Innes ,&nbsp;Charlotte E. Norris ,&nbsp;Timothy J. Philpott ,&nbsp;Terri Lacourse ,&nbsp;Barbara J. Hawkins","doi":"10.1016/j.soilbio.2025.109913","DOIUrl":"10.1016/j.soilbio.2025.109913","url":null,"abstract":"<div><div>Ectomycorrhizal (EM) fungi purportedly contribute to the enzymatic decay of soil organic matter (SOM), in contrast to arbuscular mycorrhizal (AM) stands where SOM turnover may be more fully governed by free-living saprotrophic fungi. We tested this distinction in a 30-year-old mixedwood conifer trial by comparing total peroxidase activity (including manganese-peroxidase [MnP]), fungal communities and mass of the humus layer between <em>Pseudotsuga menziesii</em> (EM host), <em>Thuja plicata</em> (AM host), and a 50:50 mixture across a natural productivity gradient. Total peroxidase and MnP activity diverged between hosts as humus C:N ratio increased, culminating in 3- to 4-fold greater enzyme activity under <em>P. menziesii</em> on low fertility soils. This soil effect also correlated positively with exchangeable Mn, highlighting a possible further restriction on SOM turnover under EM stands. Peroxidase activity was well aligned with a subset of abundant EM fungal species, notably <em>Piloderma olivaceum</em> and <em>Piloderma sphaerosporum</em>, suggesting a much greater enzymatic contribution by these symbiotic fungi in comparison to saprotrophic fungi under <em>T. plicata</em>. After three decades, mass of the humus layer averaged 2.15 kg OM m⁻² and did not yet differ among stand types. However, a 3-fold range in humus mass in correlation with declining soil fertility under <em>P</em>. <em>menziesii</em> suggests that select EM fungal taxa engaged in organic N liberation can limit SOM accumulation. This research highlights the adaptive ligninolytic enzymatic capacity of EM fungal communities and underscores how dual soil properties (low N or high Mn availability) may enhance peroxidase production and SOM turnover in EM forests.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"209 ","pages":"Article 109913"},"PeriodicalIF":9.8,"publicationDate":"2025-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144611352","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":"Wetland restoration following agricultural abandonment supports diversity and reduces stochasticity in soil fungal communities due to anaerobic-induced interspecific associations","authors":"Huijie Zheng ,&nbsp;Ye Li ,&nbsp;Deyan Liu ,&nbsp;Junji Yuan ,&nbsp;Zengming Chen ,&nbsp;Junjie Li ,&nbsp;Weixin Ding","doi":"10.1016/j.soilbio.2025.109909","DOIUrl":"10.1016/j.soilbio.2025.109909","url":null,"abstract":"<div><div>Soil fungi play a pivotal role in regulating various functions within terrestrial ecosystems. Understanding the progression of soil fungal communities during wetland restoration following agricultural abandonment is essential for assessing the sustainability of rehabilitated ecosystems. Soils along a chronosequence of paddy fields and wetlands restored for 1, 3, and 4 years were studied to investigate the dynamics of fungal diversity and assembly processes, focusing on how these changes relate to species associations and soil environmental factors, particularly redox condition and carbon (C) supply, which predominantly regulate a range of ecological services. Wetland restoration increased both soil fungal taxonomic and phylogenetic diversity. The relative contribution of nestedness increased with restoration duration, emphasising the importance of richness increases in soil fungal community succession during wetland restoration. Concurrently, stochastic assembly processes of soil fungal communities decreased with restoration duration, as indicated by a decline in the phylogenetic normalised stochasticity ratio. However, soil fungal community assembly was decoupled from anaerobic condition (indicated by ferrous iron/ferric iron ratio) and labile C supply (indicated by organic C content and the relative abundance of the di-O-alkyl C functional group). In contrast, the decrease in stochasticity was associated with enhanced species associations, reflected by increases in node number, edge number, and average degree, particularly positive associations, as shown by the rise in the positive-to-negative edge ratio during wetland restoration. This pattern might be because that despite stronger soil anaerobic condition, enriched anaerobic species (e.g., Mortierellales) could provide nutrients to aerobic species (e.g., Helotiales) through positive associations, thereby broadening fungal niche breadth. This, in turn, might cascade into more diversified and less stochastic fungal communities during wetland restoration. Overall, our results suggest that anaerobic-induced interspecific associations reduce stochasticity in soil fungal communities and provide a mechanistic perspective on the protection of soil fungal diversity during wetland restoration following agricultural abandonment.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"209 ","pages":"Article 109909"},"PeriodicalIF":9.8,"publicationDate":"2025-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144612976","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phosphorus-transforming microbes enhance phosphatase catalytic efficiency to alleviate phosphorus limitation under nitrogen and phosphorus additions in subtropical forest soil","authors":"Shuang Liu ,&nbsp;Xinyu Zhang ,&nbsp;Huimin Wang ,&nbsp;Yakov Kuzyakov ,&nbsp;Junxiao Pan ,&nbsp;Fusheng Chen ,&nbsp;Fangchao Wang ,&nbsp;Dandan Li ,&nbsp;Yuqian Tang ,&nbsp;Zeqing Ma","doi":"10.1016/j.soilbio.2025.109915","DOIUrl":"10.1016/j.soilbio.2025.109915","url":null,"abstract":"<div><div>Phosphatase catalytic efficiency (V_max/K_m) is a key determinant of soil phosphorus (P) availability and is governed by microbial P-transformations. In subtropical forest soils, low intrinsic P availability is constrained by atmospheric nitrogen (N) deposition, yet the effects of P-transforming microorganisms and microbial food webs on V_max/K_m remain unclear. This study quantifies how P-transforming microorganisms and microbial trophic interactions modulate phosphatase catalytic efficiency under N, P, and NP additions in subtropical Chinese fir plantations. Partial least squares path modelling revealed two dominant microbial pathways contributing to increased V_max/K_m: (i) N-induced acidification upregulated phosphate transporter genes (e.g., <em>pstB</em>), increasing microbial P uptake; P and NP additions alleviated microbial P limitation and downregulated P-starvation response genes (e.g., <em>phoB</em>), indicating a shift from stress-response to uptake-oriented strategies. (ii) P and NP additions increased upper trophic-level protist diversity, triggering a top-down microbial food web cascade that selectively enriched <em>Acidobacteria</em>, increased phosphatase catalytic efficiency, and increased P availability in soil. Overall, these gene-regulatory and trophic pathways explained over 60 % of the variation in phosphatase catalytic efficiency across all nutrient treatments. These findings challenge the traditional focus on phosphatase-encoding genes alone and underscore the importance of (i) phosphate transport systems, like <em>pstB</em> gene, and (ii) keystone taxa, like <em>Acidobacteria</em>, in increasing V_max/K_m. This study provides a mechanistic foundation to raisephosphatase catalytic efficiency and alleviate P limitation through targeted microbial and genetic interventions in P-deficient subtropical forest soils.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"209 ","pages":"Article 109915"},"PeriodicalIF":9.8,"publicationDate":"2025-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144603871","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":"Modelling mycelial responses to nitrogen limitation during litter decomposition","authors":"Samia Ghersheen ,&nbsp;Stefano Manzoni ,&nbsp;Marie Spohn ,&nbsp;Björn D. Lindahl","doi":"10.1016/j.soilbio.2025.109899","DOIUrl":"10.1016/j.soilbio.2025.109899","url":null,"abstract":"<div><div>Most soil organic matter models focus on carbon (C) dynamics rather than on element interactions. However, in many regions of the world, particularly at high latitudes, soil organic matter decomposition is constrained by low nitrogen (N) availability. This phenomenon is not well understood and usually not mechanistically represented in decomposition models. Here we formulated a process-based model of litter decomposition to investigate N limitation effects on fungus-driven decomposition. Unlike most other decomposition models, our model describes fungal mycelial dynamics explicitly. Fungal biomass is divided into three fractions: (1) cytoplasmic cells active in decomposition, (2) vacuolised cells with a lower N content and without decomposition capacity, and (3) dead cells (necromass). The model can predict mass loss trajectories of litter types with different N content based on site-specific parameters. The fungal mycelium responds to N limitation by increasing the proportion of vacuolised, inactive cells with a low N content, reducing decomposition rates. As a consequence of increased cell inactivation under N limitation, N accumulates in the necromass pool. To predict observed patterns of N immobilisation and release, the rate of fungal necromass decomposition has to be slow and close to that of lignin. Moreover, we found that slow mycelial growth facilitates exploitation of low N resources, whereas fast growth intensifies N-limitation. Our model disentangles the interplay between N availability, mycelial dynamics, and decomposition, pointing towards the potentials of more explicit incorporation of fungal traits in models of N limited ecosystems.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"209 ","pages":"Article 109899"},"PeriodicalIF":9.8,"publicationDate":"2025-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144603869","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":"Interpreting differences in microbial carbon and nitrogen use efficiencies estimated by isotope methods and the ecoenzyme stoichiometry model","authors":"Lifei Sun ,&nbsp;Wolfgang Wanek ,&nbsp;Daryl L. Moorhead ,&nbsp;Xinyi Yang ,&nbsp;Wenlong Gao ,&nbsp;Luiz Alberto Domeignoz-Horta","doi":"10.1016/j.soilbio.2025.109914","DOIUrl":"10.1016/j.soilbio.2025.109914","url":null,"abstract":"<div><div>Isotope methods and ecoenzyme stoichiometry are the most commonly used approaches to estimate carbon and nitrogen use efficiencies (CUE and NUE) of microbial communities. Isotope methods estimate metabolic efficiencies by tracking the allocation of substrate between catabolic and anabolic fates, whereas ecoenzyme stoichiometry estimates resource use efficiencies based on balancing substrate availability with microbial element requirements. These differences affect interpretation, which has often been overlooked, leading to misconceptions and erroneous conclusions. In this paper, we clarify key differences in frameworks for interpreting results from the two methods with respect to potential driving factors. Differences in element use efficiencies determined by isotope methods primarily reflect changes in substrate biochemical transformations within microbial communities, whereas ecoenzyme stoichiometry mirrors shifts in the match between substrate stoichiometry and microbial community element requirements. Specifically clarifying these differences provides a better understanding and complementary interpretation of microbial CUE and NUE.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"209 ","pages":"Article 109914"},"PeriodicalIF":9.8,"publicationDate":"2025-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144594760","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":"Microhabitat more than ecosystem type determines the trophic position of springtail species","authors":"Junbo Yang ,&nbsp;Gaozhong Pu ,&nbsp;Melissa Jüds ,&nbsp;Amandine Erktan ,&nbsp;Stefan Scheu ,&nbsp;Jing-Zhong Lu","doi":"10.1016/j.soilbio.2025.109912","DOIUrl":"10.1016/j.soilbio.2025.109912","url":null,"abstract":"<div><div>Trophic plasticity may intensify competition among soil animal species and reduce their high diversity, which is often maintained by trophic niche differentiation and vertical microstratification in soils. Soil decomposers such as Collembola can shift their trophic niche with changing microhabitats across soil depths (vertical variation) and between different ecosystem types (horizontal variation), but these variations need further investigation. Here, we compared the stable isotope values of 27 Collembola species between litter and soil layers in 40 forest stands, comprising monocultures of European beech, Norway spruce, Douglas fir, or mixtures of European beech with either of the two conifer species. The results showed that the δ¹⁵N values of Collembola within species were uniformly higher in soil than in the litter layer irrespective of forest type. This increase correlated with the biomass of Gram-negative bacteria but not with that of fungi. The δ¹³C values of Collembola were significantly enriched in beech forests, but were similar in Douglas fir and Norway spruce forests indicating similar effects of the two coniferous species on the basal resource use of Collembola. Overall, the results suggest that Collembola shift their diet to consume local resources available in the respective soil layer they colonize, with bacteria playing a more important role in driving variations in their trophic positions than previously assumed. By contrast, the consistent trophic position of Collembola between ecosystem types suggest access to similar food sources in the soil microhabitat, despite large changes in aboveground vegetation type. Overall this study suggests that changes in ecosystem types has little influence on the resources accessible to Collembola which presumably selectively feed on specific resources in the soil microhabitat. By contrast, variations in resource types and soil microhabitats across soil depth more strongly affect the trophic niche of Collembola, which requires plasticity to adapt to their diet.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"209 ","pages":"Article 109912"},"PeriodicalIF":9.8,"publicationDate":"2025-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144578500","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":"Livestock manure-based organic fertilization facilitates the transmission of antibiotic resistance genes across the soil-onion continuum: A significant contribution from root exudates","authors":"Zixuan Zhao ,&nbsp;Bin Luo ,&nbsp;Tao Cao ,&nbsp;Tongtong Bai ,&nbsp;Yifan Sun ,&nbsp;Hengrui Liu ,&nbsp;Li Zhang ,&nbsp;Jun Xie ,&nbsp;Jun Wang ,&nbsp;Huakang Li ,&nbsp;Zichen Duan ,&nbsp;Zixuan Gao ,&nbsp;Xiaojuan Wang ,&nbsp;Jie Gu ,&nbsp;Xun Qian ,&nbsp;James M. Tiedje","doi":"10.1016/j.soilbio.2025.109910","DOIUrl":"10.1016/j.soilbio.2025.109910","url":null,"abstract":"<div><div>The transmission and transformation patterns of antibiotic resistance genes (ARGs) in the soil-onion continuum under the application of organic fertilizers in actual agricultural cultivation are still unknown. This study systematically analyzed the occurrence characteristics of ARGs in soil and onion (roots and bulbs) under the application of organic fertilizer from livestock manure, and revealed the response mechanism of phenolic metabolites in roots. The results showed that fertilization promoted the enrichment of ARGs in the soil and onions. The abundance of ARGs in the bulbs of the pig manure and sheep manure treatment groups was 4 times and 2 times as high as that in the unfertilized group, respectively. In comparison to the bulbs, a higher abundance of ARGs was observed in the roots of onions. The 11 ARGs, including high-risk variants such as <em>tetX</em> and <em>mexE</em>, were detected co-occurring in both onion tissues and the surrounding soil. Fertilization treatment significantly changed the community composition of ARGs-related host bacteria in onion tissues. Livestock manure-based organic fertilizers elevated the potential exposure risk of ARGs in bulbs by more than 20 %. Five strains of multidrug-resistant endophytic bacteria (including <em>Streptomyces</em> and <em>Fictibacillus</em>) were isolated from the main edible parts of onion bulbs. It is worth noting that this study found that kaempferol (35–140 μg/L) and <em>p</em>-coumaric acid (2.5–10 μg/L) significantly enhanced the conjugation and transfer of the RP4 plasmid in the onion endophytes (<em>Bacillus</em> sp. and <em>Paenibacillus</em> sp.) and soil microbial communities. Root exudates were the predominant factors regulating the transmission of ARGs in the soil-onion system.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"209 ","pages":"Article 109910"},"PeriodicalIF":9.8,"publicationDate":"2025-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144578147","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 method to isolate soil organic phosphorus from other soil organic matter to determine its carbon isotope ratio","authors":"Ye Tian,&nbsp;Marie Spohn","doi":"10.1016/j.soilbio.2025.109911","DOIUrl":"10.1016/j.soilbio.2025.109911","url":null,"abstract":"<div><div>Despite the importance of soil organic phosphorus (OP) for plant nutrition, its dynamics in soil remain elusive due to the lack of multiple stable P isotopes. Here, we developed a method that isolates the soil OP pool from other soil organic matter to measure its carbon isotope signature to elucidate soil OP decomposition. We tested three extractants (H₂SO₄, HCl, and NaOH in 0.5 M) for their capacity to preferentially extract OP. For isolating OP from the extract, we evaluated different pH adjustments (pH 1.5–10) and iron- or aluminum hydroxide additions. Finally, we determined the carbon isotope ratio (δ¹³C) of the isolated OP pool. We found that the H₂SO₄ extracts had the highest OP content and the lowest organic carbon (OC):OP ratio compared to the HCl and NaOH extracts. The pH adjustments of the H₂SO₄ extracts to pH 4–7.5 removed ≥93 % of the extracted OP from the solution. The OC:OP ratio of the precipitates was the lowest (11–16) at pH 7.5, showing a strong preferential OP precipitation caused by the pH alteration. Metal hydroxide addition (combined with pH treatment) did not improve the preferential OP removal. The δ¹³C of the OP reflected differences in the vegetation (C₃/C₄) that grows at the soil sampling sites. Overall, this method provides a simple and effective approach to isolate the soil OP pool from other soil organic matter and determine its carbon isotope ratio, which opens new avenues to study soil OP dynamics.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"210 ","pages":"Article 109911"},"PeriodicalIF":9.8,"publicationDate":"2025-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144568953","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}