Stable isotope labeling of agricultural polyesters enables demonstration of their microbial utilization in soils.
Investigating active participants in the fixation of dinitrogen gas is vital as N is often a limiting factor for primary production. Biological nitrogen fixation is performed by a diverse guild of bacteria and archaea (diazotrophs), which can be free\uffe2\uff80\uff90living or symbionts. Free\uffe2\uff80\uff90living diazotrophs are widely distributed in the environment, yet our knowledge about their identity and ecophysiology is still limited. A major challenge in investigating this guild is inferring activity from genetic data as this process is highly regulated. To address this challenge, we evaluated and improved several 15N\uffe2\uff80\uff90based methods for detecting N2 fixation activity (with a focus on soil samples) and studying active diazotrophs. We compared the acetylene reduction assay and the 15N2 tracer method and demonstrated that the latter is more sensitive in samples with low activity. Additionally, tracing 15N into microbial RNA provides much higher sensitivity compared to bulk soil analysis. Active soil diazotrophs were identified with a 15N\uffe2\uff80\uff90RNA\uffe2\uff80\uff90SIP approach optimized for environmental samples and benchmarked to 15N\uffe2\uff80\uff90DNA\uffe2\uff80\uff90SIP. Lastly, we investigated the feasibility of using SIP\uffe2\uff80\uff90Raman microspectroscopy for detecting 15N\uffe2\uff80\uff90labelled cells. Taken together, these tools allow identifying and investigating active free\uffe2\uff80\uff90living diazotrophs in a highly sensitive manner in diverse environments, from bulk to the single\uffe2\uff80\uff90cell level.
", "keywords": ["Spectrum Analysis", " Raman", "BIOLOGICAL SOIL CRUSTS", "106005 Bioinformatik", "106023 Molekularbiologie", "Nitrogen Fixation", "REVEALS", "FLUORESCENCE", "Research Articles", "Soil Microbiology", "106022 Mikrobiologie", "SPECTROSCOPY", "Bacteria", "Nitrogen Isotopes", "106003 Biodiversity research", "106023 Molecular biology", "GENETIC-REGULATION", "Archaea", "6. Clean water", "SURFACE-ENHANCED RAMAN", "COMMUNITY", "106003 Biodiversit\u00e4tsforschung", "13. Climate action", "Isotope Labeling", "106022 Microbiology", "NITROGEN-FIXATION", "106005 Bioinformatics", "RIBOSOMAL-RNA", "N-2 FIXATION"]}, "links": [{"href": "https://onlinelibrary.wiley.com/doi/pdf/10.1111/1462-2920.13954"}, {"href": "https://doi.org/10.1111/1462-2920.13954"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Environmental%20Microbiology", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1111/1462-2920.13954", "name": "item", "description": "10.1111/1462-2920.13954", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1111/1462-2920.13954"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2017-12-15T00:00:00Z"}}, {"id": "10.1016/j.soilbio.2016.03.008", "type": "Feature", "geometry": null, "properties": {"updated": "2026-05-24T16:16:54Z", "type": "Journal Article", "created": "2016-03-26", "title": "Soil microbial carbon use efficiency and biomass turnover in a long-term fertilization experiment in a temperate grassland", "description": "Soil microbial carbon use efficiency (CUE), defined as the ratio of organic C allocated to growth over organic C taken up, strongly affects soil carbon (C) cycling. Despite the importance of the microbial CUE for the terrestrial C cycle, very little is known about how it is affected by nutrient availability. Therefore, we studied microbial CUE and microbial biomass turnover time in soils of a long-term fertilization experiment in a temperate grassland comprising five treatments (control, PK, NK, NP, NPK). Microbial CUE and the turnover of microbial biomass were determined using a novel substrate-independent method based on incorporation of 18O from labeled water into microbial DNA. Microbial respiration was 28-37% smaller in all three N treatments (NK, NP, and NPK) compared to the control, whereas the PK treatment did not affect microbial respiration. N-fertilization decreased microbial C uptake, while the microbial growth rate was not affected. Microbial CUE ranged between 0.31 and 0.45, and was 1.3- to 1.4-fold higher in the N-fertilized soils than in the control. The turnover time ranged between 80 and 113 days and was not significantly affected by fertilization. Net primary production (NPP) and the abundance of legumes differed strongly across the treatments, and the fungal:bacterial ratio was very low in all treatments. Structural equation modeling revealed that microbial CUE was exclusively controlled by N fertilization and that neither the abundance of legumes (as a proxy for the quality of the organic matter inputs) nor NPP (as a proxy for C inputs) had an effect on microbial CUE. Our results show that N fertilization did not only decrease microbial respiration, but also microbial C uptake, indicating that less C was intracellularly processed in the N fertilized soils. The reason for reduced C uptake and increased CUE in the N-fertilization treatments is likely an inhibition of oxidative enzymes involved in the degradation of aromatic compounds by N in combination with a reduced energy requirement for microbial N acquisition in the fertilized soils. In conclusion, the study shows that N availability can control soil C cycling by affecting microbial CUE, while plant community-mediated changes in organic matter inputs and P and K availability played no important role for C partitioning of the microbial community in this temperate grassland.
", "keywords": ["FUNGAL", "2. Zero hunger", "106022 Mikrobiologie", "Nitrogen addition", "BACTERIAL", "NITROGEN DEPOSITION", "GROWTH EFFICIENCY", "FOREST FLOOR", "Nutrients", "04 agricultural and veterinary sciences", "15. Life on land", "Stoichiometry", "ORGANIC-MATTER", "RESPIRATION", "106026 \u00d6kosystemforschung", "13. Climate action", "Nutrient limitation", "Microbial growth yield", "106022 Microbiology", "0401 agriculture", " forestry", " and fisheries", "Mean residence time", "STOICHIOMETRIC CONTROLS", "ENZYME-ACTIVITY", "106026 Ecosystem research", "COMMUNITY STRUCTURE"]}, "links": [{"href": "https://doi.org/10.1016/j.soilbio.2016.03.008"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Soil%20Biology%20and%20Biochemistry", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1016/j.soilbio.2016.03.008", "name": "item", "description": "10.1016/j.soilbio.2016.03.008", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1016/j.soilbio.2016.03.008"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2016-06-01T00:00:00Z"}}, {"id": "10.1016/j.soilbio.2019.03.028", "type": "Feature", "geometry": null, "properties": {"updated": "2026-05-24T16:16:56Z", "type": "Journal Article", "created": "2019-04-01", "title": "Coupled carbon and nitrogen losses in response to seven years of chronic warming in subarctic soils", "description": "Increasing temperatures may alter the stoichiometric demands of soil microbes and impair their capacity to stabilize carbon (C) and retain nitrogen (N), with critical consequences for the soil C and N storage at high latitude soils. Geothermally active areas in Iceland provided wide, continuous and stable gradients of\u00a0soil temperatures\u00a0to test this hypothesis. In order to characterize the stoichiometric demands of microbes from these subarctic soils, we incubated soils from ambient temperatures after the factorial addition of C, N and P substrates separately and in combination. In a second experiment, soils that had been exposed to different\u00a0in situ\u00a0warming intensities (+0, +0.5, +1.8, +3.4, +8.7, +15.9\u00a0\u00b0C above ambient) for seven years were incubated after the combined addition of C, N and P to evaluate the capacity of soil microbes to store and immobilize C and N at the different warming scenarios. The seven years of chronic soil warming triggered large and proportional soil C and N losses (4.1\u00a0\u00b1\u00a00.5% \u00b0C\u22121\u00a0of the stocks in unwarmed soils) from the upper 10\u202fcm of soil, with a predominant depletion of the physically accessible organic substrates that were weakly sorbed in\u00a0soil minerals\u00a0up to 8.7\u202f\u00b0C warming. Soil microbes met the increasing respiratory demands under conditions of low C accessibility at the expenses of a reduction of the standing biomass in warmer soils. This together with the strict microbial C:N stoichiometric demands also constrained their capacity of N retention, and increased the vulnerability of soil to N losses. Our findings suggest a strong control of\u00a0microbial physiology and C:N stoichiometric needs on the retention of soil N and on the resilience of soil C stocks from high-latitudes to warming, particularly during periods of vegetation dormancy and low C inputs.", "keywords": ["0301 basic medicine", "Microbial carbon and nutrients limitation", "Microbial biomass", "TERM", "03 medical and health sciences", "FOREST SOIL", "Temperature increase", "ORGANIC-CARBON", "Substrate induced respiration", "SDG 13 - Climate Action", "TEMPERATURE SENSITIVITY", "CYCLE", "106026 Ecosystem research", "METAANALYSIS", "2. Zero hunger", "106022 Mikrobiologie", "0303 health sciences", "CLIMATE-CHANGE", "Nitrogen loss", "AVAILABILITY", "15. Life on land", "106026 \u00d6kosystemforschung", "13. Climate action", "SDG 13 \u2013 Ma\u00dfnahmen zum Klimaschutz", "FEEDBACKS", "Nitrogen immobilization", "106022 Microbiology", "PLANT BIOMASS"]}, "links": [{"href": "https://doi.org/10.1016/j.soilbio.2019.03.028"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Soil%20Biology%20and%20Biochemistry", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1016/j.soilbio.2019.03.028", "name": "item", "description": "10.1016/j.soilbio.2019.03.028", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1016/j.soilbio.2019.03.028"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2019-07-01T00:00:00Z"}}, {"id": "10.1016/j.soilbio.2019.107521", "type": "Feature", "geometry": null, "properties": {"updated": "2026-05-24T16:16:56Z", "type": "Journal Article", "created": "2019-06-26", "title": "Soil multifunctionality is affected by the soil environment and by microbial community composition and diversity", "description": "Microorganisms are critical in mediating carbon (C) and nitrogen (N) cycling processes in soils. Yet, it has long been debated whether the processes underlying biogeochemical cycles are affected by the composition and diversity of the soil microbial community or not. The composition and diversity of soil microbial communities can be influenced by various environmental factors, which in turn are known to impact biogeochemical processes. The objectives of this study were to test effects of multiple edaphic drivers individually and represented as the multivariate soil environment interacting with microbial community composition and diversity, and concomitantly on multiple soil functions (i.e. soil enzyme activities, soil C and N processes). We employed high-throughput sequencing (Illumina MiSeq) to analyze bacterial/archaeal and fungal community composition by targeting the 16S rRNA gene and the ITS1 region of soils collected from three land uses (cropland, grassland and forest) deriving from two bedrock forms (silicate and limestone). Based on this data set we explored single and combined effects of edaphic variables on soil microbial community structure and diversity, as well as on soil enzyme activities and several soil C and N processes. We found that both bacterial/archaeal and fungal communities were shaped by the same edaphic factors, with most single edaphic variables and the combined soil environment representation exerting stronger effects on bacterial/archaeal communities than on fungal communities, as demonstrated by (partial) Mantel tests. We also found similar edaphic controls on the bacterial/archaeal/fungal richness and diversity. Soil C processes were only directly affected by the soil environment but not affected by microbial community composition. In contrast, soil N processes were significantly related to bacterial/archaeal community composition and bacterial/archaeal/fungal richness/diversity but not directly affected by the soil environment. This indicates direct control of the soil environment on soil C processes and indirect control of the soil environment on soil N processes by structuring the microbial communities. The study further highlights the importance of edaphic drivers and microbial communities (i.e. composition and diversity) on important soil C and N processes.", "keywords": ["0301 basic medicine", "570", "550", "ECOSYSTEM MULTIFUNCTIONALITY", "BACTERIAL COMMUNITY", "106027 \u00d6kotoxikologie", "FUNGAL COMMUNITIES", "Soil functions", "Article", "03 medical and health sciences", "Microbial community composition and diversity", "CARBON-USE EFFICIENCY", "106027 Ecotoxicology", "ENZYME-ACTIVITIES", "14. Life underwater", "SDG 15 \u2013 Leben an Land", "Life Below Water", "SDG 15 - Life on Land", "2. Zero hunger", "106022 Mikrobiologie", "0303 health sciences", "Agricultural and Veterinary Sciences", "LAND-USE", "SUBSTRATE USE EFFICIENCY", "Agronomy & Agriculture", "Biological Sciences", "15. Life on land", "6. Clean water", "TEMPERATE FOREST", "13. Climate action", "LONG-TERM N", "106022 Microbiology", "Edaphic drivers", "BAYESIAN CLASSIFIER", "Environmental Sciences"]}, "links": [{"href": "https://escholarship.org/content/qt83b3006k/qt83b3006k.pdf"}, {"href": "https://doi.org/10.1016/j.soilbio.2019.107521"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Soil%20Biology%20and%20Biochemistry", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1016/j.soilbio.2019.107521", "name": "item", "description": "10.1016/j.soilbio.2019.107521", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1016/j.soilbio.2019.107521"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2019-09-01T00:00:00Z"}}, {"id": "10.1016/j.soilbio.2022.108604", "type": "Feature", "geometry": null, "properties": {"updated": "2026-05-24T16:16:56Z", "type": "Journal Article", "created": "2022-03-18", "title": "From diversity to complexity: Microbial networks in soils", "description": "ABSTRACTNetwork analysis has been used for many years in ecological research to analyze organismal associations, for example in food webs, plant-plant or plant-animal interactions. Although network analysis is widely applied in microbial ecology, only recently has it entered the realms of soil microbial ecology, shown by a rapid rise in studies applying co-occurrence analysis to soil microbial communities. While this application offers great potential for deeper insights into the ecological structure of soil microbial ecosystems, it also brings new challenges related to the specific characteristics of soil datasets and the type of ecological questions that can be addressed. In this Perspectives Paper we assess the challenges of applying network analysis to soil microbial ecology due to the small-scale heterogeneity of the soil environment and the nature of soil microbial datasets. We review the different approaches of network construction that are commonly applied to soil microbial datasets and discuss their features and limitations. Using a test dataset of microbial communities from two depths of a forest soil, we demonstrate how different experimental designs and network constructing algorithms affect the structure of the resulting networks, and how this in turn may influence ecological conclusions. We will also reveal how assumptions of the construction method, methods of preparing the dataset, and definitions of thresholds affect the network structure. Finally, we discuss the particular questions in soil microbial ecology that can be approached by analyzing and interpreting specific network properties. Targeting these network properties in a meaningful way will allow applying this technique not in merely descriptive, but in hypothesis-driven research.
Using reverse microdialysis, we simulated root exudation by releasing a13C-labelled mix of low-molecular-weight organic C compounds at mm-sized locations in undisturbed soil. Combined with stable isotope tracing, we investigated the fine-scale temporal and spatial response of microbial metabolism, soil chemistry, and traced microbial respiration and uptake of exuded compounds.
Our results show that a 9-h simulated root exudation pulse leads to i) a large local respiration event and ii) alteration of the temporal dynamics of soil metabolites over the following 12\u202fday\u202fat the exudation spot. Notably, we observed a threefold increase in ammonium concentrations at 12\u202fh and increased nitrate concentrations five days after the pulse. Moreover, various short-chain fatty acids (acetate, propionate, formate) increased over the following days, indicating altered microbial metabolic pathways and activity. Phospholipid and neutral lipid fatty acids (PLFAs, NLFAs) of all major microbial groups were significantly 13C-enriched within a 5\u202fmm radius around the microdialysis probes, but not beyond. The highest relative 13C enrichment was observed in fungal NLFAs, indicating that a significant proportion of the exuded compounds had been incorporated into fungal storage compounds.
Our findings indicate that the punctual release of low-molecular-weight organic C compounds into intact soil significantly changes microbial metabolism and activity in its immediate surroundings, enhancing mineralization of native organic nitrogen. This highlights the versatility of microbial metabolic pathways in response to rapidly changing C availability and their effectiveness in increasing nutrient availability near plant roots.", "keywords": ["Oxygen depletion", "2. Zero hunger", "570", "106022 Mikrobiologie", "Root exudation", "short-chain fatty acids", "Reverse microdialysis", "reverse microdialysis", "[SDV.SA.SDS]Life Sciences [q-bio]/Agricultural sciences/Soil study", "15. Life on land", "root exudation", "6. Clean water", "Short-chain fatty acids", "Sugar metabolism", "106026 \u00d6kosystemforschung", "thizosphere priming effect", "crabtree effect", "sugar metabolism", "106022 Microbiology", "[SDV.SA.SDS] Life Sciences [q-bio]/Agricultural sciences/Soil study", "106026 Ecosystem research", "Rhizosphere priming effect"]}, "links": [{"href": "https://doi.org/10.1016/j.soilbio.2023.109259"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Soil%20Biology%20and%20Biochemistry", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1016/j.soilbio.2023.109259", "name": "item", "description": "10.1016/j.soilbio.2023.109259", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1016/j.soilbio.2023.109259"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2024-02-01T00:00:00Z"}}, {"id": "10.1038/s41396-020-00750-8", "type": "Feature", "geometry": null, "properties": {"updated": "2026-05-24T16:17:31Z", "type": "Journal Article", "created": "2020-10-06", "title": "Acidobacteria are active and abundant members of diverse atmospheric H2-oxidizing communities detected in temperate soils", "description": "Abstract
Significant rates of atmospheric dihydrogen (H2) consumption have been observed in temperate soils due to the activity of high-affinity enzymes, such as the group 1h [NiFe]-hydrogenase. We designed broadly inclusive primers targeting the large subunit gene (hhyL) of group 1h [NiFe]-hydrogenases for long-read sequencing to explore its taxonomic distribution across soils. This approach revealed a diverse collection of microorganisms harboring hhyL, including previously unknown groups and taxonomically not assignable sequences. Acidobacterial group 1h [NiFe]-hydrogenase genes were abundant and expressed in temperate soils. To support the participation of acidobacteria in H2 consumption, we studied two representative mesophilic soil acidobacteria, which expressed group 1h [NiFe]-hydrogenases and consumed atmospheric H2 during carbon starvation. This is the first time mesophilic acidobacteria, which are abundant in ubiquitous temperate soils, have been shown to oxidize H2 down to below atmospheric concentrations. As this physiology allows bacteria to survive periods of carbon starvation, it could explain the success of soil acidobacteria. With our long-read sequencing approach of group 1h [NiFe]-hydrogenase genes, we show that the ability to oxidize atmospheric levels of H2 is more widely distributed among soil bacteria than previously recognized and could represent a common mechanism enabling bacteria to persist during periods of carbon deprivation.Microbial activity in drylands tends to be confined to rare and short periods of rain. Rapid growth should be key to the maintenance of ecosystem processes in such narrow activity windows, if desiccation and rehydration cause widespread cell death due to osmotic stress. Here, simulating rain with 2H2O followed by single-cell NanoSIMS, we show that biocrust microbial communities in the Negev Desert are characterized by limited productivity, with median replication times of 6 to 19 days and restricted number of days allowing growth. Genome-resolved metatranscriptomics reveals that nearly all microbial populations resuscitate within minutes after simulated rain, independent of taxonomy, and invest their activity into repair and energy generation. Together, our data reveal a community that makes optimal use of short activity phases by fast and universal resuscitation enabling the maintenance of key ecosystem functions. We conclude that desert biocrust communities are highly adapted to surviving rapid changes in soil moisture and solute concentrations, resulting in high persistence that balances limited productivity.Nitrification, the oxidation of ammonia to nitrate, is an essential process in the biogeochemical nitrogen cycle. The first step of nitrification, ammonia oxidation, is performed by three, often co-occurring guilds of chemolithoautotrophs: ammonia-oxidizing bacteria (AOB), archaea (AOA), and complete ammonia oxidizers (comammox). Substrate kinetics are considered to be a major niche-differentiating factor between these guilds, but few AOA strains have been kinetically characterized. Here, the ammonia oxidation kinetic properties of 12 AOA representing all major cultivated phylogenetic lineages were determined using microrespirometry. Members of the genus Nitrosocosmicus have the lowest affinity for both ammonia and total ammonium of any characterized AOA, and these values are similar to previously determined ammonia and total ammonium affinities of AOB. This contrasts previous assumptions that all AOA possess much higher substrate affinities than their comammox or AOB counterparts. The substrate affinity of ammonia oxidizers correlated with their cell surface area to volume ratios. In addition, kinetic measurements across a range of pH values supports the hypothesis that\uffe2\uff80\uff94like for AOB\uffe2\uff80\uff94ammonia and not ammonium is the substrate for the ammonia monooxygenase enzyme of AOA and comammox. Together, these data will facilitate predictions and interpretation of ammonia oxidizer community structures and provide a robust basis for establishing testable hypotheses on competition between AOB, AOA, and comammox.Boreal forests are ecosystems with low nitrogen (N) availability that store globally significant amounts of carbon (C), mainly in plant biomass and soil organic matter (SOM). Although crucial for future climate change predictions, the mechanisms controlling boreal C and N pools are not well understood. Here, using a three-year field experiment, we compare SOM decomposition and stabilization in the presence of roots, with exclusion of roots but presence of fungal hyphae and with exclusion of both roots and fungal hyphae. Roots accelerate SOM decomposition compared to the root exclusion treatments, but also promote a different soil N economy with higher concentrations of organic soil N compared to inorganic soil N accompanied with the build-up of stable SOM-N. In contrast, root exclusion leads to an inorganic soil N economy (i.e., high level of inorganic N) with reduced stable SOM-N build-up. Based on our findings, we provide a framework on how plant roots affect SOM decomposition and stabilization.
", "keywords": ["roots", "0106 biological sciences", "330", "Nitrogen", "Science", "ta1171", "Hyphae", "Models", " Biological", "Plant Roots", "01 natural sciences", "Article", "LITTER DECOMPOSITION", "Soil", "POLYPHENOLS", "CARBON SEQUESTRATION", "soil organic matter", "Taiga", "SDG 13 - Climate Action", "SUGAR MAPLE", "Biomass", "Organic Chemicals", "forest ecology", "106026 Ecosystem research", "Ecosystem", "Soil Microbiology", "TANNINS", "2. Zero hunger", "106022 Mikrobiologie", "ECTOMYCORRHIZAL FUNGI", "MYCORRHIZA", "Q", "ta1182", "Forestry", "04 agricultural and veterinary sciences", "Plants", "15. Life on land", "Carbon", "Environmental sciences", "NITROGEN", "Boreal forests", "106026 \u00d6kosystemforschung", "13. Climate action", "SDG 13 \u2013 Ma\u00dfnahmen zum Klimaschutz", "106022 Microbiology", "ta1181", "0401 agriculture", " forestry", " and fisheries", "COMMUNITIES", "STORAGE"]}, "links": [{"href": "https://www.nature.com/articles/s41467-019-11993-1.pdf"}, {"href": "https://doi.org/10.1038/s41467-019-11993-1"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Nature%20Communications", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1038/s41467-019-11993-1", "name": "item", "description": "10.1038/s41467-019-11993-1", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1038/s41467-019-11993-1"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2019-09-04T00:00:00Z"}}, {"id": "10.1038/s41559-019-1055-3", "type": "Feature", "geometry": null, "properties": {"updated": "2026-05-24T16:17:34Z", "type": "Journal Article", "created": "2019-12-09", "title": "A systemic overreaction to years versus decades of warming in a subarctic grassland ecosystem", "description": "Temperature governs most biotic processes, yet we know little about how warming affects whole ecosystems. Here we examined the responses of 128\u2009components of a subarctic grassland to either 5-8 or >50\u2009years of soil warming. Warming of >50\u2009years drove the ecosystem to a new steady state possessing a distinct biotic composition and reduced species richness, biomass and soil organic matter. However, the warmed state was preceded by an overreaction to warming, which was related to organism physiology and was evident after 5-8\u2009years. Ignoring this overreaction yielded errors of >100% for 83\u2009variables when predicting their responses to a realistic warming scenario of 1\u2009\u00b0C over 50\u2009years, although some, including soil carbon content, remained stable after 5-8\u2009years. This study challenges long-term ecosystem predictions made from short-term observations, and provides a framework for characterization of ecosystem responses to sustained climate change.", "keywords": ["0301 basic medicine", "570", "Environmental management", "INCREASES", "Ecosystem ecology", "Climate Change", "Evolutionary biology", "TERM", "630", "Article", "Carbon Cycle", "Soil", "03 medical and health sciences", "SDG 13 - Climate Action", "106026 Ecosystem research", "Life Below Water", "Ecosystem", "106022 Mikrobiologie", "0303 health sciences", "Ecology", "Climate-change ecology", "SHIFTS", "Biological Sciences", "15. Life on land", "Grassland", "106026 \u00d6kosystemforschung", "13. Climate action", "SDG 13 \u2013 Ma\u00dfnahmen zum Klimaschutz", "FEEDBACKS", "106022 Microbiology", "VEGETATION", "SENSITIVITY", "Environmental Sciences", "SOIL RESPIRATION", "RESPONSES"]}, "links": [{"href": "https://escholarship.org/content/qt99v0g8pc/qt99v0g8pc.pdf"}, {"href": "https://doi.org/10.1038/s41559-019-1055-3"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Nature%20Ecology%20%26amp%3B%20Evolution", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1038/s41559-019-1055-3", "name": "item", "description": "10.1038/s41559-019-1055-3", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1038/s41559-019-1055-3"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2019-12-09T00:00:00Z"}}, {"id": "10.1038/s41561-020-0612-3", "type": "Feature", "geometry": null, "properties": {"updated": "2026-05-24T16:17:34Z", "type": "Journal Article", "created": "2020-07-27", "title": "Persistence of soil organic carbon caused by functional complexity", "description": "Soil organic carbon management has the potential to aid climate change mitigation through drawdown of atmospheric carbon dioxide. To be effective, such management must account for processes influencing carbon storage and re-emission at different space and time scales. Achieving this requires a conceptual advance in our understanding to link carbon dynamics from the scales at which processes occur to the scales at which decisions are made. Here, we propose that soil carbon persistence can be understood through the lens of decomposers as a result of functional complexity derived from the interplay between spatial and temporal variation of molecular diversity and composition. For example, co-location alone can determine whether a molecule is decomposed, with rapid changes in moisture leading to transport of organic matter and constraining the fitness of the microbial community, while greater molecular diversity may increase the metabolic demand of, and thus potentially limit, decomposition. This conceptual shift accounts for emergent behaviour of the microbial community and would enable soil carbon changes to be predicted without invoking recalcitrant carbon forms that have not been observed experimentally. Functional complexity as a driver of soil carbon persistence suggests soil management should be based on constant care rather than one-time action to lock away carbon in soils.", "keywords": ["[SDE] Environmental Sciences", "DECOMPOSITION", "2. Zero hunger", "106022 Mikrobiologie", "[SDE.MCG]Environmental Sciences/Global Changes", "UNCERTAINTY", "04 agricultural and veterinary sciences", "INPUTS", "15. Life on land", "TRANSPORT", "MODEL", "[SDE.MCG] Environmental Sciences/Global Changes", "106026 \u00d6kosystemforschung", "13. Climate action", "SDG 13 \u2013 Ma\u00dfnahmen zum Klimaschutz", "[SDE]Environmental Sciences", "SDG 13 - Climate Action", "Meteorology & Atmospheric Sciences", "106022 Microbiology", "GROWTH", "0401 agriculture", " forestry", " and fisheries", "TURNOVER", "PLANT", "106026 Ecosystem research", "MATTER"]}, "links": [{"href": "http://www.nature.com/articles/s41561-020-0612-3.pdf"}, {"href": "https://escholarship.org/content/qt84n3398c/qt84n3398c.pdf"}, {"href": "https://doi.org/10.1038/s41561-020-0612-3"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Nature%20Geoscience", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1038/s41561-020-0612-3", "name": "item", "description": "10.1038/s41561-020-0612-3", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1038/s41561-020-0612-3"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2020-07-27T00:00:00Z"}}, {"id": "10.1038/s42003-022-04178-y", "type": "Feature", "geometry": null, "properties": {"updated": "2026-05-24T16:17:37Z", "type": "Journal Article", "created": "2022-11-17", "title": "Both abundant and rare fungi colonizing Fagus sylvatica ectomycorrhizal root-tips shape associated bacterial communities", "description": "AbstractEctomycorrhizal fungi live in close association with their host plants and form complex interactions with bacterial/archaeal communities in soil. We investigated whether abundant or rare ectomycorrhizal fungi on root-tips of young beech trees (Fagus sylvatica) shape bacterial/archaeal communities. We sequenced 16S rRNA genes and fungal internal transcribed spacer regions of individual root-tips and used ecological networks to detect the tendency of certain assemblies of fungal and bacterial/archaeal taxa to inhabit the same root-tip (i.e. modularity). Individual ectomycorrhizal root-tips hosted distinct fungal communities associated with unique bacterial/archaeal communities. The structure of the fungal-bacterial/archaeal association was determined by both, dominant and rare fungi. Integrating our data in a conceptual framework suggests that the effect of rare fungi on the bacterial/archaeal communities of ectomycorrhizal root-tips contributes to assemblages of bacteria/archaea on root-tips. This highlights the potential impact of complex fine-scale interactions between root-tip associated fungi and other soil microorganisms for the ectomycorrhizal symbiosis.Microbial soil habitats are characterized by rapid shifts in substrate and nutrient availabilities, as well as chemical and physical parameters. One such parameter that can vary in soil is oxygen; thus, microbial survival is dependent on adaptation to this substrate. To better understand the metabolic abilities and adaptive strategies to oxygen-deprived environments, we combined genomics with transcriptomics of a model organism, Acidobacterium capsulatum, to explore the effect of decreasing, environmentally relevant oxygen concentrations. The decrease from 10 to 0.1\uffc2\uffa0\uffc2\uffb5M oxygen (3.6 to 0.036 pO2% present atmospheric level, respectively) caused the upregulation of the transcription of genes involved in signal transduction mechanisms, energy production and conversion and secondary metabolites biosynthesis, transport, and catabolism based on clusters of orthologous group categories. Contrary to established observations for aerobic metabolism, key genes in oxidative stress response were significantly upregulated at lower oxygen concentrations, presumably due to an NADH/NAD+ redox ratio imbalance as the cells transitioned into nanoxia. Furthermore, A. capsulatum adapted to nanoxia by inducing a respiro-fermentative metabolism and rerouting fluxes of its central carbon and energy pathways to adapt to high NADH/NAD+ redox ratios. Our results reveal physiological features and metabolic capabilities that allowed A. capsulatum to adapt to oxygen-limited conditions, which could expand into other environmentally relevant soil strains.Quantifying global patterns of terrestrial nitrogen (N) cycling is central to predicting future patterns of primary productivity, carbon sequestration, nutrient fluxes to aquatic systems and climate forcing. With limited direct measures of soil N cycling at the global scale, syntheses of the 15N:14N ratio of soil organic matter across climate gradients provide key insights into understanding global patterns of N cycling. In synthesizing data from over 6000 soil samples, we show strong global relationships among soil N isotopes, mean annual temperature (MAT), mean annual precipitation (MAP) and the concentrations of organic carbon and clay in soil. In both hot ecosystems and dry ecosystems, soil organic matter was more enriched in 15N than in corresponding cold ecosystems or wet ecosystems. Below a MAT of 9.8\uffc2\uffb0C, soil \uffce\uffb415N was invariant with MAT. At the global scale, soil organic C concentrations also declined with increasing MAT and decreasing MAP. After standardizing for variation among mineral soils in soil C and clay concentrations, soil \uffce\uffb415N showed no consistent trends across global climate and latitudinal gradients. Our analyses could place new constraints on interpretations of patterns of ecosystem N cycling and global budgets of gaseous N loss.
", "keywords": ["N-15 Natural-Abundance", "550", "Ecosystem ecology", "TROPICAL FORESTS", "Organic chemistry", "Suelo", "Nitrogen cycle", "01 natural sciences", "Nutrient cycle", "cycle de l'azote", "CARBON", "Agricultural and Biological Sciences", "Soil", "Terrestrial ecosystem", "Isotopes", "https://purl.org/becyt/ford/1.6", "Soil water", "SDG 13 - Climate Action", "N-15 NATURAL-ABUNDANCE", "Climate change", "croisement de donn\u00e9es", "Milieux et Changements globaux", "SDG 15 \u2013 Leben an Land", "Global change", "SDG 15 - Life on Land", "2. Zero hunger", "106022 Mikrobiologie", "Climatic Factors", "Tropical Forests", "Ecology", "Geography", "Nitr\u00f3geno", "Nutrient Cycling", "FRACTIONATION", "Litter Decomposition", "ECOSYSTEM ECOLOGY", "Life Sciences", "ecosystem ecology", "Cycling", "Forestry", "Is\u00f3topos", "Carbon cycle", "04 agricultural and veterinary sciences", "Nitrogen Cycle", "Soil carbon", "6. Clean water", "Organic-Matter", "Earth and Planetary Sciences", "ORGANIC-MATTER", "Chemistry", "PRECIPITATION", "SDG 13 \u2013 Ma\u00dfnahmen zum Klimaschutz", "Physical Sciences", "106022 Microbiology", "carbone du sol", "Stable Isotope Analysis of Groundwater and Precipitation", "Ecosystem Functioning", "570", "STABLE ISOTOPE", "Biogeochemical Cycling of Nutrients in Aquatic Ecosystems", "Stable isotope analysis", "Nitrogen", "[SDE.MCG]Environmental Sciences/Global Changes", "Soil Science", "stable isotope analysis;ecosystem ecology", "Article", "Environmental science", "LITTER DECOMPOSITION", "sol min\u00e9ral", "INORGANIC NITROGEN", "Geochemistry and Petrology", "stable isotope analysis", "Carbono", "Environmental Chemistry", "Factores Clim\u00e1ticos", "https://purl.org/becyt/ford/1", "Biology", "Ecosystem", "0105 earth and related environmental sciences", "Soil science", "Soil organic matter", "Soil Fertility", "climat", "AVAILABILITY", "Nitrogen Dynamics", "15. Life on land", "Carbon", "Inorganic", "NITROGEN", "MODEL", "[SDE.MCG] Environmental Sciences/Global Changes", "13. Climate action", "FOS: Biological sciences", "Environmental Science", "PATTERNS", "0401 agriculture", " forestry", " and fisheries", "Soil Carbon Dynamics and Nutrient Cycling in Ecosystems"]}, "links": [{"href": "https://scholars.unh.edu/context/faculty_pubs/article/1042/viewcontent/srep08280.pdf"}, {"href": "https://edoc.unibas.ch/37215/1/srep08280.pdf"}, {"href": "https://doi.org/10.1038/srep08280"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Scientific%20Reports", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1038/srep08280", "name": "item", "description": "10.1038/srep08280", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1038/srep08280"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2015-02-06T00:00:00Z"}}, {"id": "10.1101/2023.10.03.560709", "type": "Feature", "geometry": null, "properties": {"updated": "2026-05-24T16:18:15Z", "type": "Journal Article", "created": "2023-10-04", "title": "Bacteria face trade-offs in the decomposition of complex biopolymers", "description": "AbstractAlthough depolymerization of complex carbohydrates is a growth-limiting bottleneck for microbial decomposers, we still lack understanding about how the production of different types of extracellular enzymes affect individual microbes and in turn the performance of whole decomposer communities. In this work we use a theoretical model to evaluate the potential trade-offs faced by microorganisms in biopolymer decomposition which arise due to the varied biochemistry of different depolymerizing enzyme classes. We specifically consider two broad classes of depolymerizing extracellular enzymes, which are widespread across microbial taxa: exo-enzymes that cleave small units from the ends of polymer chains and endo-enzymes that act at random positions generating degradation products of varied sizes. Our results demonstrate a fundamental trade-off in the production of these enzymes, which is independent of system\uffe2\uff80\uff99s complexity and which appears solely from the intrinsically different temporal depolymerization dynamics. As a consequence, specialists that produce either exo- or only endo-enzymes limit their growth to high or low substrate conditions, respectively. Conversely, generalists that produce both enzymes in an optimal ratio expand their niche and benefit from the synergy between the two enzymes. Finally, our results show that, in spatially-explicit environments, consortia composed of endo- and exo-specialists can only exist under oligotrophic conditions. In summary, our analysis demonstrates that the (evolutionary or ecological) selection of a depolymerization pathway will affect microbial fitness under low- or high substrate conditions, with impacts on the ecological dynamics of microbial communities. It provides a possible explanation why many polysaccharide degraders in nature show the genetic potential to produce both of these enzyme classes.
Author summaryThe decomposition of polysaccharides by microbes is a key process in the global carbon cycle. It requires the joint action of a variety of microbially-produced extracellular enzymes. They can be broadly classified into endo-enzymes, that act in the middle of polymers, and exo-enzymes, that cleave units from polymer ends. Little is known about the benefits for microbes producing a certain enzyme type and the interplay between enzyme producing strategies in mixed communities. This hampers our comprehensive understanding of decomposition in terrestrial and marine ecosystems and thus limits the prediction of decomposition processes, for example in a changing climate.
Based on theoretical modelling, we revealed a fundamental trade-off in the action of these enzymes. While exo-enzymes are more efficient at high substrate conditions, endo-enzymes perform better when substrate is low. Generalists producing both enzymes expand their ecological niche of substrate availability compared to specialists only producing one of the two types. Complementary specialists only co-exist in oligotrophic conditions. We conclude that producing enzymes for specific steps within polymer degradation represents relevant ecological strategies for microbes in decomposer communities.Soils provide essential ecosystem services and represent the most diverse habitat on Earth. It has been suggested that the presence of various physico-chemically heterogeneous microhabitats supports the enormous diversity of microbial communities in soil. However, little is known about the relationship between microbial communities and their immediate environment at the micro- to millimetre scale. In this study, we examined whether bacteria, archaea, and fungi organize into distinct communities in individual 2-mm-sized soil aggregates and compared them to communities of homogenized bulk soil samples. Furthermore, we investigated their relationship to their local environment by concomitantly determining microbial community structure and physico-chemical properties from the same individual aggregates. Aggregate communities displayed exceptionally high beta-diversity, with 3\uffe2\uff80\uff934 aggregates collectively capturing more diversity than their homogenized parent soil core. Up to 20%\uffe2\uff80\uff9330% of ASVs (particularly rare ones) were unique to individual aggregates selected within a few centimetres. Aggregates and bulk soil samples showed partly different dominant phyla, indicating that taxa that are potentially driving biogeochemical processes at the small scale may not be recognized when analysing larger soil volumes. Microbial community composition and richness of individual aggregates were closely related to aggregate-specific carbon and nitrogen content, carbon stable-isotope composition, and soil moisture, indicating that aggregates provide a stable environment for sufficient time to allow co-development of communities and their environment. We conclude that the soil microbiome is a metacommunity of variable subcommunities. Our study highlights the necessity to study small, spatially coherent soil samples to better understand controls of community structure and community-mediated processes in soils.
Drought periods are projected to become more severe and more frequent in many European regions. While effects of single strong droughts on plant and microbial carbon (C) dynamics have been studied in some detail, impacts of recurrent drought events are still little understood.
We tested whether the legacy of extreme experimental drought affects responses of plant and microbial C and nitrogen (N) turnover to further drought and rewetting. In a mountain grassland, we conducted a 13C pulse\uffe2\uff80\uff90chase experiment during a naturally occurring drought and rewetting event in plots previously exposed to experimental droughts and in ambient controls (AC). After labelling, we traced 13C below\uffe2\uff80\uff90ground allocation and incorporation into soil microbes using phospholipid fatty acid biomarkers.
Drought history (DH) had no effects on the standing shoot and fine root plant biomass. However, plants with experimental DH displayed decreased shoot N concentrations and increased fine root N concentrations relative to those in AC. During the natural drought, plants with DH assimilated and allocated less 13C below\uffe2\uff80\uff90ground; moreover, fine root respiration was reduced and not fuelled by fresh C compared to plants in AC.
Regardless of DH, microbial biomass remained stable during natural drought and rewetting. Although microbial communities initially differed in their composition between soils with and without DH, they responded to the natural drought and rewetting in a similar way: gram\uffe2\uff80\uff90positive bacteria increased, while fungal and gram\uffe2\uff80\uff90negative bacteria remained stable. In soils with DH, a strongly reduced uptake of recent plant\uffe2\uff80\uff90derived 13C in microbial biomarkers was observed during the natural drought, pointing to a smaller fraction of active microbes or to a microbial community that is less dependent on plant C.
Synthesis. Drought history can induce changes in above\uffe2\uff80\uff90 vs. below\uffe2\uff80\uff90ground plant N concentrations and affect the response of plant C turnover to further droughts and rewetting by decreasing plant C uptake and below\uffe2\uff80\uff90ground allocation. DH does not affect the responses of the microbial community to further droughts and rewetting, but alters microbial functioning, particularly the turnover of recent plant\uffe2\uff80\uff90derived carbon, during and after further drought periods.
", "keywords": ["0301 basic medicine", "plant-soil (below-ground) interactions", "NITROGEN TURNOVER", "Biomass Allocation", "microbial community composition", "Negibacteria", "drought", "phospholipid fatty acid", "nitrogen", "Microbial community composition", "Plant\u2013Soil (Below\u2010ground) Interactions", "Recovery", "ROOT RESPIRATION", "Plant-soil (below-ground) interactions", "CLIMATE EXTREMES", "C pulse labelling", "Below-ground carbon allocation", "2. Zero hunger", "106022 Mikrobiologie", "0303 health sciences", "SOIL INTERACTIONS", "below-ground carbon allocation", "C-13 pulse labelling", "Grassland", "6. Clean water", "Europe", "Phospholipid", "ORGANIC-MATTER", "Mountain Region", "Posibacteria", "DIOXIDE PULSES", "Phospholipid fatty acid", "106022 Microbiology", "Root/shoot Ratio", "Belowground Biomass", "Ecosystem Resilience", "Nitrogen", "Microbial Community", "Carbon Isotope", "Soil-vegetation Interaction", "recovery", "SUMMER DROUGHT", "03 medical and health sciences", "Rewetting", "Community Composition", "plant\u2013soil (below-ground) interactions", "WATER-STRESS", "resilience", "Drought", "Resilience", "RESILIENCE", "15. Life on land", "Turnover", "Microbial Activity", "13. Climate action", "Fatty Acid", "RESPONSES"]}, "links": [{"href": "https://doi.org/10.1111/1365-2745.12593"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Journal%20of%20Ecology", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1111/1365-2745.12593", "name": "item", "description": "10.1111/1365-2745.12593", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1111/1365-2745.12593"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2016-05-24T00:00:00Z"}}, {"id": "10.1111/1462-2920.15751", "type": "Feature", "geometry": null, "properties": {"updated": "2026-05-24T16:18:20Z", "type": "Journal Article", "created": "2021-09-28", "title": "Novel Alcaligenes ammonioxydans sp. nov. from wastewater treatment sludge oxidizes ammonia to N2 with a previously unknown pathway", "description": "SummaryHeterotrophic nitrifiers are able to oxidize and remove ammonia from nitrogen\uffe2\uff80\uff90rich wastewaters but the genetic elements of heterotrophic ammonia oxidation are poorly understood. Here, we isolated and identified a novel heterotrophic nitrifier, Alcaligenes ammonioxydans sp. nov. strain HO\uffe2\uff80\uff901, oxidizing ammonia to hydroxylamine and ending in the production of N2 gas. Genome analysis revealed that strain HO\uffe2\uff80\uff901 encoded a complete denitrification pathway but lacks any genes coding for homologous to known ammonia monooxygenases or hydroxylamine oxidoreductases. Our results demonstrated strain HO\uffe2\uff80\uff901 denitrified nitrite (not nitrate) to N2 and N2O at anaerobic and aerobic conditions respectively. Further experiments demonstrated that inhibition of aerobic denitrification did not stop ammonia oxidation and N2 production. A gene cluster (dnfT1RT2ABCD) was cloned from strain HO\uffe2\uff80\uff901 and enabled E. coli accumulated hydroxylamine. Sub\uffe2\uff80\uff90cloning showed that genetic cluster dnfAB or dnfABC already enabled E. coli cells to produce hydroxylamine and further to 15N2 from (15NH4)2SO4. Transcriptome analysis revealed these three genes dnfA, dnfB and dnfC were significantly upregulated in response to ammonia stimulation. Taken together, we concluded that strain HO\uffe2\uff80\uff901 has a novel dnf genetic cluster for ammonia oxidation and this dnf genetic cluster encoded a previously unknown pathway of direct ammonia oxidation (Dirammox) to N2.
", "keywords": ["Alcaligenes ammonioxydans sp. nov.", "0301 basic medicine", "106014 Genomics", "Nitrogen", "HYDROXYLAMINE OXIDASE", "direct ammonia oxidation (Dirammox)", "OXIDATION", "REDUCTASE", "Water Purification", "THIOSPHAERA-PANTOTROPHA", "PYRUVIC-OXIME", "03 medical and health sciences", "heterotrophic nitrifier", "Ammonia", "106014 Genomik", "Escherichia coli", "Alcaligenes", "wastewater", "Nitrites", "106022 Mikrobiologie", "HETEROTROPHIC NITRIFICATION", "0303 health sciences", "PURIFICATION", "Sewage", "AEROBIC DENITRIFICATION", "Nitrification", "Aerobiosis", "6. Clean water", "NITROGEN", "FAECALIS", "Denitrification", "106022 Microbiology", "Oxidation-Reduction"]}, "links": [{"href": "https://onlinelibrary.wiley.com/doi/pdf/10.1111/1462-2920.15751"}, {"href": "https://doi.org/10.1111/1462-2920.15751"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Environmental%20Microbiology", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1111/1462-2920.15751", "name": "item", "description": "10.1111/1462-2920.15751", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1111/1462-2920.15751"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2021-09-28T00:00:00Z"}}, {"id": "10.1111/1462-2920.16213", "type": "Feature", "geometry": null, "properties": {"updated": "2026-05-24T16:18:21Z", "type": "Journal Article", "created": "2022-10-18", "title": "Application of stable\u2010isotope labelling techniques for the detection of active diazotrophs", "description": "SummaryInvestigating active participants in the fixation of dinitrogen gas is vital as N is often a limiting factor for primary production. Biological nitrogen fixation is performed by a diverse guild of bacteria and archaea (diazotrophs), which can be free\uffe2\uff80\uff90living or symbionts. Free\uffe2\uff80\uff90living diazotrophs are widely distributed in the environment, yet our knowledge about their identity and ecophysiology is still limited. A major challenge in investigating this guild is inferring activity from genetic data as this process is highly regulated. To address this challenge, we evaluated and improved several 15N\uffe2\uff80\uff90based methods for detecting N2 fixation activity (with a focus on soil samples) and studying active diazotrophs. We compared the acetylene reduction assay and the 15N2 tracer method and demonstrated that the latter is more sensitive in samples with low activity. Additionally, tracing 15N into microbial RNA provides much higher sensitivity compared to bulk soil analysis. Active soil diazotrophs were identified with a 15N\uffe2\uff80\uff90RNA\uffe2\uff80\uff90SIP approach optimized for environmental samples and benchmarked to 15N\uffe2\uff80\uff90DNA\uffe2\uff80\uff90SIP. Lastly, we investigated the feasibility of using SIP\uffe2\uff80\uff90Raman microspectroscopy for detecting 15N\uffe2\uff80\uff90labelled cells. Taken together, these tools allow identifying and investigating active free\uffe2\uff80\uff90living diazotrophs in a highly sensitive manner in diverse environments, from bulk to the single\uffe2\uff80\uff90cell level.Ammonia\uffe2\uff80\uff90oxidising archaea (AOA) are important microorganisms contributing towards the nitrogen flux in the environment. Unlike archaea from other major phyla, genetic tools are yet to be developed for the AOA, and identification of antibiotic resistance markers for selecting mutants is required for a genetic system. The aim of this study was to test the effects of selected antibiotics (hygromycin B, neomycin, apramycin, puromycin, novobiocin) on pure cultures of three well studied AOA strains, \uffe2\uff80\uff98Candidatus Nitrosocosmicus franklandianus C13\uffe2\uff80\uff99, Nitrososphaera viennensis EN76 and Nitrosopumilus maritimus SCM1. Puromycin, hygromycin B and neomycin inhibited some but not all tested archaeal strains. All strains were resistant to apramycin and inhibited by novobiocin to various degrees. As N. viennensis EN76 was relatively more resistant to the tested antibiotics, a wider range of concentrations and compounds (chloramphenicol, trimethoprim, statins) was tested against this strain. N. viennensis EN76 was inhibited by trimethoprim, but not by chloramphenicol, and growth recovered within days in the presence of simvastatin, suggesting either degradation of, or spontaneous resistance against, this compound. This study highlights the physiological differences between different genera of AOA and has identified new candidate antibiotics for selective enrichment and the development of selectable markers for genetic systems in AOA.Thermal adaptations of soil microorganisms could mitigate or facilitate global warming effects on soil organic matter (SOM) decomposition and soil CO2 efflux. We incubated soil from warmed and control subplots of a forest soil warming experiment to assess whether 9\uffc2\uffa0years of soil warming affected the rates and the temperature sensitivity of the soil CO2 efflux, extracellular enzyme activities, microbial efficiency, and gross N mineralization. Mineral soil (0\uffe2\uff80\uff9310\uffc2\uffa0cm depth) was incubated at temperatures ranging from 3 to 23\uffc2\uffa0\uffc2\uffb0C. No adaptations to long\uffe2\uff80\uff90term warming were observed regarding the heterotrophic soil CO2 efflux (R10 warmed: 2.31\uffc2\uffa0\uffc2\uffb1\uffc2\uffa00.15\uffc2\uffa0\uffce\uffbcmol\uffc2\uffa0m\uffe2\uff88\uff922\uffc2\uffa0s\uffe2\uff88\uff921, control: 2.34\uffc2\uffa0\uffc2\uffb1\uffc2\uffa00.29\uffc2\uffa0\uffce\uffbcmol\uffc2\uffa0m\uffe2\uff88\uff922\uffc2\uffa0s\uffe2\uff88\uff921; Q10 warmed: 2.45\uffc2\uffa0\uffc2\uffb1\uffc2\uffa00.06, control: 2.45\uffc2\uffa0\uffc2\uffb1\uffc2\uffa00.04). Potential enzyme activities increased with incubation temperature, but the temperature sensitivity of the enzymes did not differ between the warmed and the control soils. The ratio of C\uffc2\uffa0:\uffc2\uffa0N acquiring enzyme activities was significantly higher in the warmed soil. Microbial biomass\uffe2\uff80\uff90specific respiration rates increased with incubation temperature, but the rates and the temperature sensitivity (Q10 warmed: 2.54\uffc2\uffa0\uffc2\uffb1\uffc2\uffa00.23, control 2.75\uffc2\uffa0\uffc2\uffb1\uffc2\uffa00.17) did not differ between warmed and control soils. Microbial substrate use efficiency (SUE) declined with increasing incubation temperature in both, warmed and control, soils. SUE and its temperature sensitivity (Q10 warmed: 0.84\uffc2\uffa0\uffc2\uffb1\uffc2\uffa00.03, control: 0.88\uffc2\uffa0\uffc2\uffb1\uffc2\uffa00.01) did not differ between warmed and control soils either. Gross N mineralization was invariant to incubation temperature and was not affected by long\uffe2\uff80\uff90term soil warming. Our results indicate that thermal adaptations of the microbial decomposer community are unlikely to occur in C\uffe2\uff80\uff90rich calcareous temperate forest soils.
", "keywords": ["0106 biological sciences", "570", "substrate use efficiency", "Nitrogen", "ARCTIC SOIL", "Acclimatization", "Forests", "soil CO2 efflux", "Global Warming", "01 natural sciences", "630", "COMMUNITY COMPOSITION", "BOREAL FOREST", "Soil", "gross N mineralization", "SEASONAL PATTERNS", "thermal adaptation", "EXTRACELLULAR ENZYMES", "CARBON-USE EFFICIENCY", "soil warming", "Enzyme activities", "BEECH FOREST", "ENZYME-ACTIVITY", "Soil Microbiology", "2. Zero hunger", "106022 Mikrobiologie", "Soil CO efflux", "NITROGEN AVAILABILITY", "04 agricultural and veterinary sciences", "Carbon Dioxide", "15. Life on land", "Primary Research Articles", "Thermal adaptation", "enzyme activities", "13. Climate action", "Austria", "106022 Microbiology", "Soil warming", "0401 agriculture", " forestry", " and fisheries", "CYCLE FEEDBACKS", "Gross N mineralization", "Seasons", "Substrate use efficiency"]}, "links": [{"href": "https://doi.org/10.1111/gcb.12996"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Global%20Change%20Biology", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1111/gcb.12996", "name": "item", "description": "10.1111/gcb.12996", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1111/gcb.12996"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2015-09-28T00:00:00Z"}}, {"id": "10.1111/j.1469-8137.2010.03321.x", "type": "Feature", "geometry": null, "properties": {"updated": "2026-05-24T16:18:40Z", "type": "Journal Article", "created": "2010-06-11", "title": "Belowground Carbon Allocation By Trees Drives Seasonal Patterns Of Extracellular Enzyme Activities By Altering Microbial Community Composition In A Beech Forest Soil", "description": "*Plant seasonal cycles alter carbon (C) and nitrogen (N) availability for soil microbes, which may affect microbial community composition and thus feed back on microbial decomposition of soil organic material and plant N availability. The temporal dynamics of these plant-soil interactions are, however, unclear. *Here, we experimentally manipulated the C and N availability in a beech forest through N fertilization or tree girdling and conducted a detailed analysis of the seasonal pattern of microbial community composition and decomposition processes over 2 yr. *We found a strong relationship between microbial community composition and enzyme activities over the seasonal course. Phenoloxidase and peroxidase activities were highest during late summer, whereas cellulase and protease peaked in late autumn. Girdling, and thus loss of mycorrhiza, resulted in an increase in soil organic matter-degrading enzymes and a decrease in cellulase and protease activity. *Temporal changes in enzyme activities suggest a switch of the main substrate for decomposition between summer (soil organic matter) and autumn (plant litter). Our results indicate that ectomycorrhizal fungi are possibly involved in autumn cellulase and protease activity. Our study shows that, through belowground C allocation, trees significantly alter soil microbial communities, which may affect seasonal patterns of decomposition processes.", "keywords": ["Nitrogen", "Climate", "Trees", "Soil", "Mycorrhizae", "401902 Soil science", "Fagus", "Biomass", "Phospholipids", "Soil Microbiology", "106022 Mikrobiologie", "Bacteria", "Research", "Temperature", "04 agricultural and veterinary sciences", "15. Life on land", "401902 Bodenkunde", "Carbon", "Solubility", "106030 Pflanzen\u00f6kologie", "106022 Microbiology", "Regression Analysis", "0401 agriculture", " forestry", " and fisheries", "106030 Plant ecology", "Seasons", "Extracellular Space", "Biomarkers"]}, "links": [{"href": "https://doi.org/10.1111/j.1469-8137.2010.03321.x"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/New%20Phytologist", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1111/j.1469-8137.2010.03321.x", "name": "item", "description": "10.1111/j.1469-8137.2010.03321.x", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1111/j.1469-8137.2010.03321.x"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2010-07-19T00:00:00Z"}}, {"id": "10.1111/nph.12569", "type": "Feature", "geometry": null, "properties": {"updated": "2026-05-24T16:18:46Z", "type": "Journal Article", "created": "2013-10-31", "title": "Experimental Drought Reduces The Transfer Of Recently Fixed Plant Carbon To Soil Microbes And Alters The Bacterial Community Composition In A Mountain Meadow", "description": "Summary
Drought affects plants and soil microorganisms, but it is still not clear how it alters the carbon (C) transfer at the plant\uffe2\uff80\uff93microbial interface. Here, we tested direct and indirect effects of drought on soil microbes and microbial turnover of recent plant\uffe2\uff80\uff90derived C in a mountain meadow.
Microbial community composition was assessed using phospholipid fatty acids (PLFAs); the allocation of recent plant\uffe2\uff80\uff90derived C to microbial groups was analysed by pulse\uffe2\uff80\uff90labelling of canopy sections with 13CO2 and the subsequent tracing of the label into microbial PLFAs.
Microbial biomass was significantly higher in plots exposed to a severe experimental drought. In addition, drought induced a shift of the microbial community composition, mainly driven by an increase of Gram\uffe2\uff80\uff90positive bacteria. Drought reduced belowground C allocation, but not the transfer of recently plant\uffe2\uff80\uff90assimilated C to fungi, and in particular reduced tracer uptake by bacteria. This was accompanied by an increase of 13C in the extractable organic C pool during drought, which was even more pronounced after plots were mown.
We conclude that drought weakened the link between plant and bacterial, but not fungal, C turnover, and facilitated the growth of potentially slow\uffe2\uff80\uff90growing, drought\uffe2\uff80\uff90adapted soil microbes, such as Gram\uffe2\uff80\uff90positive bacteria.
", "keywords": ["Time Factors", "Nitrogen", "Mowing", "Mountain grassland", "Carbon Cycle", "Microbial community composition", "Soil", "Biomass", "Ecosystem", "Soil Microbiology", "2. Zero hunger", "106022 Mikrobiologie", "Carbon Isotopes", "Drought", "Research", "Microbiota", "Water", "Carbon allocation", "Microclimate", "04 agricultural and veterinary sciences", "15. Life on land", "Carbon", "6. Clean water", "Droughts", "C pulse-labelling", "13. Climate action", "Austria", "Phospholipid fatty acids", "106022 Microbiology", "0401 agriculture", " forestry", " and fisheries"]}, "links": [{"href": "https://doi.org/10.1111/nph.12569"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/New%20Phytologist", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1111/nph.12569", "name": "item", "description": "10.1111/nph.12569", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1111/nph.12569"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2013-10-31T00:00:00Z"}}, {"id": "10.1111/nph.19112", "type": "Feature", "geometry": null, "properties": {"updated": "2026-05-24T16:18:47Z", "type": "Journal Article", "created": "2023-06-29", "title": "Gold\u2010FISH enables targeted NanoSIMS analysis of plant\u2010associated bacteria", "description": "Summary
Bacteria colonize plant roots and engage in reciprocal interactions with their hosts. However, the contribution of individual taxa or groups of bacteria to plant nutrition and fitness is not well characterized due to a lack of in\uffc2\uffa0situ evidence of bacterial activity.
To address this knowledge gap, we developed an analytical approach that combines the identification and localization of individual bacteria on root surfaces via gold\uffe2\uff80\uff90based in\uffc2\uffa0situ hybridization with correlative NanoSIMS imaging of incorporated stable isotopes, indicative of metabolic activity.
We incubated Kosakonia strain DS\uffe2\uff80\uff901\uffe2\uff80\uff90associated, gnotobiotically grown rice plants with 15N\uffe2\uff80\uff93N2 gas to detect in\uffc2\uffa0situ N2 fixation activity. Bacterial cells along the rhizoplane showed\uffc2\uffa0heterogeneous patterns of 15N enrichment, ranging from the natural isotope abundance levels up to 12.07 at% 15N (average and median of 3.36 and 2.85 at% 15N, respectively, n\uffe2\uff80\uff89=\uffe2\uff80\uff89697 cells).
The presented correlative optical and chemical imaging analysis is applicable to a broad range of studies investigating plant\uffe2\uff80\uff93microbe interactions. For example, it enables verification of the in\uffc2\uffa0situ metabolic activity of host\uffe2\uff80\uff90associated commercialized strains or plant growth\uffe2\uff80\uff90promoting bacteria, thereby disentangling their role in plant nutrition. Such data facilitate the design of plant\uffe2\uff80\uff93microbe combinations for improvement of crop management.
Biological Market Models are common evolutionary frameworks to understand the maintenance of mutualism in mycorrhizas. \uffe2\uff80\uff98Surplus C\uffe2\uff80\uff99 hypotheses provide an alternative framework where stoichiometry and source\uffe2\uff80\uff93sink dynamics govern mycorrhizal function. A critical difference between these frameworks is whether carbon transfer from plants is regulated by nutrient transfer from fungi or through source\uffe2\uff80\uff93sink dynamics. In this review, we: provide a historical perspective; summarize studies that asked whether plants transfer more carbon to fungi that transfer more nutrients; conduct a meta\uffe2\uff80\uff90analysis to assess whether mycorrhizal plant growth suppressions are related to carbon transfer; and review literature on cellular mechanisms for carbon transfer. In sum, current knowledge does not indicate that carbon transfer from plants is directly regulated by nutrient delivery from fungi. Further, mycorrhizal plant growth responses were linked to nutrient uptake rather than carbon transfer. These findings are more consistent with \uffe2\uff80\uff98Surplus C\uffe2\uff80\uff99 hypotheses than Biological Market Models. However, we also identify research gaps, and future research may uncover a mechanism directly linking carbon and nutrient transfer. Until then, we urge caution when applying economic terminology to describe mycorrhizas. We present a synthesis of ideas, consider knowledge gaps, and suggest experiments to advance the field.Stable isotope labeling of agricultural polyesters enables demonstration of their microbial utilization in soils.
Due to their abilities to survive intense radiation and low water availability, hypersaline microbial mats are often suggested to be analogs of potential extraterrestrial life. However, even on Earth, the limitations imposed on microbial processes by saturation-level salinity have rarely been studied in situ . Nitrification is a ubiquitous microbially mediated process in the environment and an essential process in engineered systems such as wastewater and drinking water treatment plants. However, nitrification also contributes to fertilizer loss from agricultural environments, increasing the eutrophication of downstream aquatic ecosystems, and produces the greenhouse gas nitrous oxide. As ammonia-oxidizing bacteria are the most dominant ammonia-oxidizing microbes in fertilized agricultural soils, understanding their responses to a variety of environmental conditions is essential for curbing the negative environmental effects of nitrification. Notably, oxygen limitation has been reported to significantly increase nitric oxide and nitrous oxide production during nitrification. Here, we investigate the physiology of the best-characterized ammonia-oxidizing bacterium, Nitrosomonas europaea , growing under oxygen-limited conditions. Microbial life is surprisingly abundant and diverse in global desert ecosystems. In these environments, microorganisms endure a multitude of physicochemical stresses, including low water potential, carbon and nitrogen starvation, and extreme temperatures. In this review, we summarize our current understanding of the energetic mechanisms and trophic dynamics that underpin microbial function in desert ecosystems. Accumulating evidence suggests that dormancy is a common strategy that facilitates microbial survival in response to water and carbon limitation. This study represents a comprehensive community-wide genome-centered metagenome analysis of biological soil crust (BSC) communities in arid environments, providing insights into the distribution of genes encoding different energy generation mechanisms, as well as survival strategies, among populations in an arid soil ecosystem. It reveals the metabolic potential of several uncultured and previously unsequenced microbial genera, families, and orders, as well as differences in the metabolic potential between the most abundant BSC populations and their cultured relatives, highlighting once more the danger of inferring function on the basis of taxonomy. <p>Soil organic matter (SOM) is important for soil fertility and climate change mitigation. Agricultural management - including soil amendments - can improve soil fertility and contribute to climate change mitigation by stabilising carbon in soils. This calls for cost-effective parameters to assess&#160; the influence of management practices on SOM. The current study aimed at understanding how sensitive the parameters active/permanganate oxidisable carbon (AC) and nitrogen mineralisation potential (NMP) react to different agricultural management practices compared to total organic carbon (TOC) and total nitrogen (Nt). We aimed to gain a better understanding of SOM processes, mainly regarding depth distribution and seasonality of SOM dynamics using AC and NMP.</p><p>Data were obtained in five Austrian long-term field experiments (LTEs) testing four management practices: i) tillage, ii) compost application, iii) crop residue management, and iv) mineral fertilisation.</p><p>AC was specifically sensitive in detecting the effect of tillage treatment at different soil depths. NMP differentiated between all different tillage treatments in the top soil layer, it showed the temporal dynamics between the years in the compost LTE, and it was identified as an early detection property in the crop residue LTE. Both AC and NMP detected short-term fluctuations better than TOC and Nt over the course of two years in the crop residue LTE. Thus, we suggest that AC and NMP are two valuable soil biochemical parameters providing more detailed information on C and N dynamics regarding depth distribution and seasonal dynamics and react more sensitively to different agricultural management practices compared to TOC and Nt. They should be integrated in monitoring agricultural LTEs and in field analyses conducted by farmers. However, when evaluating results of long-term carbon storage, their sensitivity towards annual fluctuations should be taken into account.</p> <p>Soil organic matter (SOM) is important for soil fertility and climate change mitigation. Agricultural management - including soil amendments - can improve soil fertility and contribute to climate change mitigation by stabilising carbon in soils. This calls for cost-effective parameters to assess&#160; the influence of management practices on SOM. The current study aimed at understanding how sensitive the parameters active/permanganate oxidisable carbon (AC) and nitrogen mineralisation potential (NMP) react to different agricultural management practices compared to total organic carbon (TOC) and total nitrogen (Nt). We aimed to gain a better understanding of SOM processes, mainly regarding depth distribution and seasonality of SOM dynamics using AC and NMP.</p><p>Data were obtained in five Austrian long-term field experiments (LTEs) testing four management practices: i) tillage, ii) compost application, iii) crop residue management, and iv) mineral fertilisation.</p><p>AC was specifically sensitive in detecting the effect of tillage treatment at different soil depths. NMP differentiated between all different tillage treatments in the top soil layer, it showed the temporal dynamics between the years in the compost LTE, and it was identified as an early detection property in the crop residue LTE. Both AC and NMP detected short-term fluctuations better than TOC and Nt over the course of two years in the crop residue LTE. Thus, we suggest that AC and NMP are two valuable soil biochemical parameters providing more detailed information on C and N dynamics regarding depth distribution and seasonal dynamics and react more sensitively to different agricultural management practices compared to TOC and Nt. They should be integrated in monitoring agricultural LTEs and in field analyses conducted by farmers. However, when evaluating results of long-term carbon storage, their sensitivity towards annual fluctuations should be taken into account.</p>
Soils provide essential ecosystem services and represent the most diverse habitat on Earth. It has been suggested that the presence of various physico-chemically heterogeneous microhabitats supports the enormous diversity of microbial communities in soil. However, little is known about the relationship between microbial communities and their immediate environment at the micro- to millimetre scale. In this study, we examined whether bacteria, archaea, and fungi organize into distinct communities in individual 2-mm-sized soil aggregates and compared them to communities of homogenized bulk soil samples. Furthermore, we investigated their relationship to their local environment by concomitantly determining microbial community structure and physico-chemical properties from the same individual aggregates. Aggregate communities displayed exceptionally high beta-diversity, with 3\uffe2\uff80\uff934 aggregates collectively capturing more diversity than their homogenized parent soil core. Up to 20%\uffe2\uff80\uff9330% of ASVs (particularly rare ones) were unique to individual aggregates selected within a few centimetres. Aggregates and bulk soil samples showed partly different dominant phyla, indicating that taxa that are potentially driving biogeochemical processes at the small scale may not be recognized when analysing larger soil volumes. Microbial community composition and richness of individual aggregates were closely related to aggregate-specific carbon and nitrogen content, carbon stable-isotope composition, and soil moisture, indicating that aggregates provide a stable environment for sufficient time to allow co-development of communities and their environment. We conclude that the soil microbiome is a metacommunity of variable subcommunities. Our study highlights the necessity to study small, spatially coherent soil samples to better understand controls of community structure and community-mediated processes in soils.Although depolymerization of complex carbohydrates is a growth-limiting bottleneck for microbial decomposers, we still lack understanding about how the production of different types of extracellular enzymes affect individual microbes and in turn the performance of whole decomposer communities. In this work we use a theoretical model to evaluate the potential trade-offs faced by microorganisms in biopolymer decomposition which arise due to the varied biochemistry of different depolymerizing enzyme classes. We specifically consider two broad classes of depolymerizing extracellular enzymes, which are widespread across microbial taxa: exo-enzymes that cleave small units from the ends of polymer chains and endo-enzymes that act at random positions generating degradation products of varied sizes. Our results demonstrate a fundamental trade-off in the production of these enzymes, which is independent of system\uffe2\uff80\uff99s complexity and which appears solely from the intrinsically different temporal depolymerization dynamics. As a consequence, specialists that produce either exo- or only endo-enzymes limit their growth to high or low substrate conditions, respectively. Conversely, generalists that produce both enzymes in an optimal ratio expand their niche and benefit from the synergy between the two enzymes. Finally, our results show that, in spatially-explicit environments, consortia composed of endo- and exo-specialists can only exist under oligotrophic conditions. In summary, our analysis demonstrates that the (evolutionary or ecological) selection of a depolymerization pathway will affect microbial fitness under low- or high substrate conditions, with impacts on the ecological dynamics of microbial communities. It provides a possible explanation why many polysaccharide degraders in nature show the genetic potential to produce both of these enzyme classes.
Author summaryThe decomposition of polysaccharides by microbes is a key process in the global carbon cycle. It requires the joint action of a variety of microbially-produced extracellular enzymes. They can be broadly classified into endo-enzymes, that act in the middle of polymers, and exo-enzymes, that cleave units from polymer ends. Little is known about the benefits for microbes producing a certain enzyme type and the interplay between enzyme producing strategies in mixed communities. This hampers our comprehensive understanding of decomposition in terrestrial and marine ecosystems and thus limits the prediction of decomposition processes, for example in a changing climate.
Based on theoretical modelling, we revealed a fundamental trade-off in the action of these enzymes. While exo-enzymes are more efficient at high substrate conditions, endo-enzymes perform better when substrate is low. Generalists producing both enzymes expand their ecological niche of substrate availability compared to specialists only producing one of the two types. Complementary specialists only co-exist in oligotrophic conditions. We conclude that producing enzymes for specific steps within polymer degradation represents relevant ecological strategies for microbes in decomposer communities.Soil microbial carbon use efficiency (CUE), defined as the ratio of organic C allocated to growth over organic C taken up, strongly affects soil carbon (C) cycling. Despite the importance of the microbial CUE for the terrestrial C cycle, very little is known about how it is affected by nutrient availability. Therefore, we studied microbial CUE and microbial biomass turnover time in soils of a long-term fertilization experiment in a temperate grassland comprising five treatments (control, PK, NK, NP, NPK). Microbial CUE and the turnover of microbial biomass were determined using a novel substrate-independent method based on incorporation of 18O from labeled water into microbial DNA. Microbial respiration was 28-37% smaller in all three N treatments (NK, NP, and NPK) compared to the control, whereas the PK treatment did not affect microbial respiration. N-fertilization decreased microbial C uptake, while the microbial growth rate was not affected. Microbial CUE ranged between 0.31 and 0.45, and was 1.3- to 1.4-fold higher in the N-fertilized soils than in the control. The turnover time ranged between 80 and 113 days and was not significantly affected by fertilization. Net primary production (NPP) and the abundance of legumes differed strongly across the treatments, and the fungal:bacterial ratio was very low in all treatments. Structural equation modeling revealed that microbial CUE was exclusively controlled by N fertilization and that neither the abundance of legumes (as a proxy for the quality of the organic matter inputs) nor NPP (as a proxy for C inputs) had an effect on microbial CUE. Our results show that N fertilization did not only decrease microbial respiration, but also microbial C uptake, indicating that less C was intracellularly processed in the N fertilized soils. The reason for reduced C uptake and increased CUE in the N-fertilization treatments is likely an inhibition of oxidative enzymes involved in the degradation of aromatic compounds by N in combination with a reduced energy requirement for microbial N acquisition in the fertilized soils. In conclusion, the study shows that N availability can control soil C cycling by affecting microbial CUE, while plant community-mediated changes in organic matter inputs and P and K availability played no important role for C partitioning of the microbial community in this temperate grassland.
", "keywords": ["FUNGAL", "2. Zero hunger", "106022 Mikrobiologie", "Nitrogen addition", "BACTERIAL", "NITROGEN DEPOSITION", "GROWTH EFFICIENCY", "FOREST FLOOR", "Nutrients", "04 agricultural and veterinary sciences", "15. Life on land", "Stoichiometry", "ORGANIC-MATTER", "RESPIRATION", "106026 \u00d6kosystemforschung", "13. Climate action", "Nutrient limitation", "Microbial growth yield", "106022 Microbiology", "0401 agriculture", " forestry", " and fisheries", "Mean residence time", "STOICHIOMETRIC CONTROLS", "ENZYME-ACTIVITY", "106026 Ecosystem research", "COMMUNITY STRUCTURE"]}, "links": [{"href": "https://doi.org/2309129852"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Soil%20Biology%20and%20Biochemistry", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "2309129852", "name": "item", "description": "2309129852", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/2309129852"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2016-06-01T00:00:00Z"}}, {"id": "2932651632", "type": "Feature", "geometry": null, "properties": {"updated": "2026-05-24T16:24:55Z", "type": "Journal Article", "created": "2019-04-01", "title": "Coupled carbon and nitrogen losses in response to seven years of chronic warming in subarctic soils", "description": "Increasing temperatures may alter the stoichiometric demands of soil microbes and impair their capacity to stabilize carbon (C) and retain nitrogen (N), with critical consequences for the soil C and N storage at high latitude soils. Geothermally active areas in Iceland provided wide, continuous and stable gradients of\u00a0soil temperatures\u00a0to test this hypothesis. In order to characterize the stoichiometric demands of microbes from these subarctic soils, we incubated soils from ambient temperatures after the factorial addition of C, N and P substrates separately and in combination. In a second experiment, soils that had been exposed to different\u00a0in situ\u00a0warming intensities (+0, +0.5, +1.8, +3.4, +8.7, +15.9\u00a0\u00b0C above ambient) for seven years were incubated after the combined addition of C, N and P to evaluate the capacity of soil microbes to store and immobilize C and N at the different warming scenarios. The seven years of chronic soil warming triggered large and proportional soil C and N losses (4.1\u00a0\u00b1\u00a00.5% \u00b0C\u22121\u00a0of the stocks in unwarmed soils) from the upper 10\u202fcm of soil, with a predominant depletion of the physically accessible organic substrates that were weakly sorbed in\u00a0soil minerals\u00a0up to 8.7\u202f\u00b0C warming. Soil microbes met the increasing respiratory demands under conditions of low C accessibility at the expenses of a reduction of the standing biomass in warmer soils. This together with the strict microbial C:N stoichiometric demands also constrained their capacity of N retention, and increased the vulnerability of soil to N losses. Our findings suggest a strong control of\u00a0microbial physiology and C:N stoichiometric needs on the retention of soil N and on the resilience of soil C stocks from high-latitudes to warming, particularly during periods of vegetation dormancy and low C inputs.", "keywords": ["0301 basic medicine", "Microbial carbon and nutrients limitation", "Microbial biomass", "TERM", "03 medical and health sciences", "FOREST SOIL", "Temperature increase", "ORGANIC-CARBON", "Substrate induced respiration", "SDG 13 - Climate Action", "TEMPERATURE SENSITIVITY", "CYCLE", "106026 Ecosystem research", "METAANALYSIS", "2. Zero hunger", "106022 Mikrobiologie", "0303 health sciences", "CLIMATE-CHANGE", "Nitrogen loss", "AVAILABILITY", "15. Life on land", "106026 \u00d6kosystemforschung", "13. Climate action", "SDG 13 \u2013 Ma\u00dfnahmen zum Klimaschutz", "FEEDBACKS", "Nitrogen immobilization", "106022 Microbiology", "PLANT BIOMASS"]}, "links": [{"href": "https://doi.org/2932651632"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Soil%20Biology%20and%20Biochemistry", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "2932651632", "name": "item", "description": "2932651632", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/2932651632"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2019-07-01T00:00:00Z"}}, {"id": "10067/1974270151162165141", "type": "Feature", "geometry": null, "properties": {"updated": "2026-05-24T16:23:43Z", "type": "Journal Article", "created": "2023-05-10", "title": "Tree stem and soil methane and nitrous oxide fluxes, but not carbon dioxide fluxes, switch sign along a topographic gradient in a tropical forest", "description": "PurposeSignificant rates of atmospheric dihydrogen (H2) consumption have been observed in temperate soils due to the activity of high-affinity enzymes, such as the group 1h [NiFe]-hydrogenase. We designed broadly inclusive primers targeting the large subunit gene (hhyL) of group 1h [NiFe]-hydrogenases for long-read sequencing to explore its taxonomic distribution across soils. This approach revealed a diverse collection of microorganisms harboring hhyL, including previously unknown groups and taxonomically not assignable sequences. Acidobacterial group 1h [NiFe]-hydrogenase genes were abundant and expressed in temperate soils. To support the participation of acidobacteria in H2 consumption, we studied two representative mesophilic soil acidobacteria, which expressed group 1h [NiFe]-hydrogenases and consumed atmospheric H2 during carbon starvation. This is the first time mesophilic acidobacteria, which are abundant in ubiquitous temperate soils, have been shown to oxidize H2 down to below atmospheric concentrations. As this physiology allows bacteria to survive periods of carbon starvation, it could explain the success of soil acidobacteria. With our long-read sequencing approach of group 1h [NiFe]-hydrogenase genes, we show that the ability to oxidize atmospheric levels of H2 is more widely distributed among soil bacteria than previously recognized and could represent a common mechanism enabling bacteria to persist during periods of carbon deprivation.Carbon storage is a common strategy of soil microbes to cope with resource fluctuations. Fungi use neutral lipids (triacylglycerols, TAGs) for storage, which can be quantified via their derived fatty acids (NLFAs). NLFAs specific to bacteria can also be abundant in soils, but are rarely analysed as soil bacteria are assumed to not store TAGs. Instead, bacterial NLFAs are thought to derive from degraded phospholipids (diacylglycerols, DAGs), and thus indicate bacterial necromass, but this interpretation lacks evidence. In this perspective, we synthesise knowledge from the literature and our own experimental results on the origin of soil bacterial NLFAs. In sum, we provide evidence that bacterial NLFAs are predominantly derived from TAGs used for carbon storage: (1) Several pure culture studies provide evidence for TAG production in selected bacterial isolates. (2) Screening of genomes showed that wax ester synthase/diacylglycerol acyltransferases, which mediate the last step of TAG synthesis, are abundant in bacterial isolates from soil, suggesting a widespread genetic capability to produce TAGs. (3) We experimentally created conditions of excess labile carbon by adding isotopically labelled glucose to soil. Glucose-13C was rapidly allocated into bacterial NLFAs, with higher relative enrichment than phospholipid-derived fatty acids, indicating storage. (4) DAGs are not necessarily produced\uffe2\uff80\uff94and may only be intermediate compounds\uffe2\uff80\uff94during phospholipid degradation. We conclude that soil bacterial NLFAs are mainly derived from storage compounds, but a potential contribution from degraded phospholipids needs further validation. Isotopic labelling could resolve this, making NLFAs a valuable biomarker for microbial storage compounds in soil.
HighlightsBacterial NLFAs originate from triacylglycerols (TAGs) or degraded phospholipids
Neutral lipids are not necessarily produced during phospholipid degradation
Soil bacteria have the genetic potential to produce TAGs for storage
Rapid transfer of excess glucose-13C into soil bacterial NLFAs suggests storage
Bacterial NLFAs are markers for carbon storage rather than necromassNetwork analysis has been used for many years in ecological research to analyze organismal associations, for example in food webs, plant-plant or plant-animal interactions. Although network analysis is widely applied in microbial ecology, only recently has it entered the realms of soil microbial ecology, shown by a rapid rise in studies applying co-occurrence analysis to soil microbial communities. While this application offers great potential for deeper insights into the ecological structure of soil microbial ecosystems, it also brings new challenges related to the specific characteristics of soil datasets and the type of ecological questions that can be addressed. In this Perspectives Paper we assess the challenges of applying network analysis to soil microbial ecology due to the small-scale heterogeneity of the soil environment and the nature of soil microbial datasets. We review the different approaches of network construction that are commonly applied to soil microbial datasets and discuss their features and limitations. Using a test dataset of microbial communities from two depths of a forest soil, we demonstrate how different experimental designs and network constructing algorithms affect the structure of the resulting networks, and how this in turn may influence ecological conclusions. We will also reveal how assumptions of the construction method, methods of preparing the dataset, and definitions of thresholds affect the network structure. Finally, we discuss the particular questions in soil microbial ecology that can be approached by analyzing and interpreting specific network properties. Targeting these network properties in a meaningful way will allow applying this technique not in merely descriptive, but in hypothesis-driven research.