Stable Isotope Ecology (CER, Kyoto Univ.)

@stableisotopeecol.bsky.social

23 hours ago

Field-Based Quantification of Isotope Effects during Nitrogen Transformations Using High-Resolution Geochemical Monitoring and Numerical Modeling at an Agricultural Site Nitrogen transformations in agricultural soils strongly influence nitrate leaching, greenhouse gas emissions, and water quality. However, quantifying these processes under field conditions remains cha...

Field-Based Quantification of Isotope Effects during Nitrogen Transformations Using High-Resolution Geochemical Monitoring and Numerical Modeling at an Agricultural Site | ACS ES&T Water pubs.acs.org/doi/10.1021/... #stableisotopes

Stable Isotope Ecology (CER, Kyoto Univ.)

@stableisotopeecol.bsky.social

1 day ago

Depth of nutrient uptake by deep-rooted plants is regulated by water availability | PNAS The capacity of some plants to access water and nutrients at depths greater than one meter is a critical functional trait that confers resistance t...

Depth of nutrient uptake by deep-rooted plants is regulated by water availability | PNAS www.pnas.org/doi/10.1073/... #stableisotopes

Stable Isotope Ecology (CER, Kyoto Univ.)

@stableisotopeecol.bsky.social

1 day ago

Using a Multi-Tracer Approach to Examine Perfluoroalkyl Substance Sources and Dietary Exposure Pathways in Pacific Bald Eagles Perfluoroalkyl substances (PFAS) are globally distributed contaminants that bioaccumulate in avian apex predators, yet species-specific bioaccumulation processes and links to dietary sources remain poorly resolved. Using an integrative, multi-habitat sampling framework, we blood sampled 89 bald eagle (Haliaeetus leucocephalus) nestlings across eight regions from the Pacific coast of British Columbia (BC), Canada and quantified 17 PFAS. We paired contaminant data with stable isotope analyses (δ15N, δ13C, δ34S) to characterize trophic position and habitat use, and fatty acid (FA) profiling to partition aquatic vs terrestrial prey sources, while modeling biological covariates. Our most parsimonious model describing spatial variation in PFAS exposure included region and nestling age. PFAS profiles were dominated by PFOS (mean = 23.5; range 2.1–159 ng/mL), comprising 33–72% of ∑17 PFAS, with remaining burdens composed of PFNA, PFDA, PFUdA, and PFTrDA. Stable isotopes did not uniformly predict PFAS concentrations; however, PFUdA and PFTrDA were positively correlated with δ13C and ∑ Omega-3 FAs, consistent with marine-derived diets. PFOS and PFHxS were negatively correlated with ∑ Omega-6 FAs, suggesting greater biomagnification in nestlings feeding within terrestrial or mammalian food webs. To our knowledge, this work represents the first comprehensive assessment of PFAS exposure in Pacific bald eagles and is also one of the first attempts to apply a multi-dietary tracer approach to contextualize habitat use and dietary pathways of PFAS in a regional apex predator.

Using a Multi-Tracer Approach to Examine Perfluoroalkyl Substance Sources and Dietary Exposure Pathways in Pacific Bald Eagles | Environmental Science & Technology pubs.acs.org/doi/10.1021/... #stableisotopes

Stable Isotope Ecology (CER, Kyoto Univ.)

@stableisotopeecol.bsky.social

1 day ago

Global Role of Vanadium for Cryptogamic Nitrogen Fixation in Extratropical Forests Biological nitrogen fixation (BNF) by nitrogenase is often assumed to rely on molybdenum as an enzymatic cofactor, despite molybdenum scarcity in terrestrial ecosystems relative to vanadium and iron, ...

Global Role of Vanadium for Cryptogamic Nitrogen Fixation in Extratropical Forests | Environmental Science & Technology pubs.acs.org/doi/10.1021/... #stableisotopes

Stable Isotope Ecology (CER, Kyoto Univ.)

@stableisotopeecol.bsky.social

1 day ago

Sulfur Isotopes Reveal Spatial Variation in Waterbird Trace Element Contamination from Tropical Estuaries to the Open Ocean Marine and freshwater pollution is a major environmental concern, yet the spatial extent of estuarine contamination in marine food webs remains poorly understood. In this study, we sampled blood from ...

Sulfur Isotopes Reveal Spatial Variation in Waterbird Trace Element Contamination from Tropical Estuaries to the Open Ocean | Environmental Science & Technology pubs.acs.org/doi/10.1021/... #stableisotopes

Stable Isotope Ecology (CER, Kyoto Univ.)

@stableisotopeecol.bsky.social

1 day ago

Long-term nitrogen burial exceeds denitrification in global fjords - Nature Communications Contrary to previous assumptions, nitrogen burial – not denitrification – dominates nitrogen loss in fjords, accounting for up to 18% of oceanic nitrogen burial. Deoxygenation may yet alter the future...

Cheung, H.L.S., Levin, L.S., Smeaton, C. et al. Long-term nitrogen burial exceeds denitrification in global fjords. Nat Commun 17, 3148 (2026). doi.org/10.1038/s414... #stableisotopes

Stable Isotope Ecology (CER, Kyoto Univ.)

@stableisotopeecol.bsky.social

1 day ago

Tracing terrestrial nitrogen contributions to the salt marsh food web of the Obitsu River estuary in Tokyo Bay using compound-specific δ15N analysis of amino acids - Progress in Earth and Planetary Sc... Abstract Salt marshes, which sustain high productivity, serve as essential living environments for a wide range of organisms. The aquatic food web in salt marshes is basically supported by the high pr...

Tracing terrestrial nitrogen contributions to the salt marsh food web of the Obitsu River estuary in Tokyo Bay using compound-specific δ15N analysis of amino acids. Prog Earth Planet Sci 13, 18 (2026). doi.org/10.1186/s406... #stableisotopes

Stable Isotope Ecology (CER, Kyoto Univ.)

@stableisotopeecol.bsky.social

1 day ago

Comparisons of strontium isotope ratios in the water and otoliths suggest narrow habitat ranges of freshwater three-spined sticklebacks in Otsuchi, Japan - Progress in Earth and Planetary Science Stable isotope analysis is useful in elucidating the flow of elements among organisms and environments. Understanding the movement of organisms is important for the conservation of ecosystems, and rad...

Uji, K., Nakano, T., Shin, KC. et al. Comparisons of strontium isotope ratios in the water and otoliths suggest narrow habitat ranges of freshwater three-spined sticklebacks in Otsuchi, Japan. #stableisotopes Prog Earth Planet Sci 13, 21 (2026). doi.org/10.1186/s406...

Stable Isotope Ecology (CER, Kyoto Univ.)

@stableisotopeecol.bsky.social

1 day ago

Discrepancies between feeding ecology and trophic position based on nitrogen isotopic composition in endosymbiont-bearing benthic foraminifers - Progress in Earth and Planetary Science Symbiotic relationships of microorganisms including eukaryotic algae and prokaryotes affect holobiont nitrogen metabolism and provide survival advantages in extreme environments; however, the influenc...

Maeda, A., Naito, Y.I., Tsuchiya, M. et al. Discrepancies between feeding ecology and trophic position based on nitrogen isotopic composition in endosymbiont-bearing benthic foraminifers. #stableisotopes Prog Earth Planet Sci 13, 19 (2026). doi.org/10.1186/s406...

Stable Isotope Ecology (CER, Kyoto Univ.)

@stableisotopeecol.bsky.social

1 day ago

Dynamics of 13C and 15N isotopes in fire-affected soils under rotational shifting cultivation in Northern Thailand - Biogeochemistry Understanding the biogeochemical consequences of fire and land-use history in tropical upland systems is essential for sustainable soil management. We investigated the vertical distribution of stable ...

Arunrat, N., Sereenonchai, S., Sakurada, H. et al. Dynamics of 13C and 15N isotopes in fire-affected soils under rotational shifting cultivation in Northern Thailand. #stableisotopes Biogeochemistry 169, 11 (2026). doi.org/10.1007/s105...

Stable Isotope Ecology (CER, Kyoto Univ.)

@stableisotopeecol.bsky.social

1 day ago

Variation in Soil Organic Carbon Across a Latitudinal Chronosequence of Mangrove Poleward Expansion - Ecosystems The critical carbon sink provided by coastal wetlands, known as blue carbon, can be affected by multiple aspects of climate change. One important example is warming-induced mangrove poleward expansion...

Kang, Y., Assavapanuvat, P., Osland, M.J. et al. Variation in Soil Organic Carbon Across a Latitudinal Chronosequence of Mangrove Poleward Expansion. #stableisotopes Ecosystems 29, 2 (2026). doi.org/10.1007/s100...

Stable Isotope Ecology (CER, Kyoto Univ.)

@stableisotopeecol.bsky.social

1 day ago

Bottom-up Effects of Seabird Colonies on Arctic Benthic Communities Mediated by Kelp Forests - Ecosystems Arctic seabird colonies concentrate marine-derived nutrients on land through the deposition of guano, which fertilizes the vegetation and supports local consumers. However, the process in which nutrie...

Zmudczyńska-Skarbek, K., Balazy, P., Chełchowski, M. et al. Bottom-up Effects of Seabird Colonies on Arctic Benthic Communities Mediated by Kelp Forests. #stableisotopes Ecosystems 29, 26 (2026). doi.org/10.1007/s100...

Stable Isotope Ecology (CER, Kyoto Univ.)

@stableisotopeecol.bsky.social

1 day ago

Acclimation of the Nitrogen Cycle to Changes in Precipitation - Ecosystems Climate change drivers elicit ecosystem responses that vary through time. We propose that the mismatch between equilibrium and transient ecosystem response defines ecological acclimation. As precipita...

Currier, C.M., Reichmann, L.G. & Sala, O.E. Acclimation of the Nitrogen Cycle to Changes in Precipitation. Ecosystems 29, 25 (2026). doi.org/10.1007/s100... #stableisotopes

Stable Isotope Ecology (CER, Kyoto Univ.)

@stableisotopeecol.bsky.social

1 day ago

Stable isotope analysis shows limited assimilation of carbohydrates in muscle tissue of an omnivorous fish - Environmental Biology of Fishes Stable isotope analysis is key to understanding trophic relationships, but how different diet components are incorporated into tissues remains unclear. Understanding trophic relationships for omnivoro...

Sturtz, J.M., Peoples, B., Goforth, R. et al. Stable isotope analysis shows limited assimilation of carbohydrates in muscle tissue of an omnivorous fish. #stableisotopes Environ Biol Fish 109, 10 (2026). doi.org/10.1007/s106...

Stable Isotope Ecology (CER, Kyoto Univ.)

@stableisotopeecol.bsky.social

1 day ago

Muscle-fin tissue stable isotope relationships for studying Arctic grayling (Thymallus arcticus) and bull trout (Salvelinus confluentus) trophic ecology - Environmental Biology of Fishes Concern over the use of lethal sampling for routine ecological research work has driven the development of equations for equating non-lethally sampled tissue to the archival database of previously let...

Power, M., Clevenger, I. & Martins, E.G. Muscle-fin tissue stable isotope relationships for studying Arctic grayling (Thymallus arcticus) and bull trout (Salvelinus confluentus) trophic ecology. #stableisotopes Environ Biol Fish 109, 42 (2026). doi.org/10.1007/s106...

Stable Isotope Ecology (CER, Kyoto Univ.)

@stableisotopeecol.bsky.social

1 day ago

Minimally Destructive Radiocarbon Dating of Bone Rationale Bone is commonly used in radiocarbon dating in archaeology and other disciplines. Despite advances in collagen extraction protocols, the process remains destructive, requiring sawing, dril...

Minimally Destructive Radiocarbon Dating of Bone - Higham - 2026 - Rapid Communications in Mass Spectrometry #stableisotopes analyticalsciencejournals.onlinelibrary.wiley.com/doi/full/10....

Stable Isotope Ecology (CER, Kyoto Univ.)

@stableisotopeecol.bsky.social

1 day ago

Continuum of denitrification to end-member controls on nitrate isotopic ratios: evidence from meta-analyses and a six-year record of seasonality from Kentucky, USA The isotopic ratios of nitrate (δ15NNO3 and δ18ONO3) are common tracers of nitrate source and transformation in soil and aquatic systems. However, inv…

Continuum of denitrification to end-member controls on nitrate isotopic ratios: evidence from meta-analyses and a six-year record of seasonality from Kentucky, USA #stableisotopes www.sciencedirect.com/science/arti...

Stable Isotope Ecology (CER, Kyoto Univ.)

@stableisotopeecol.bsky.social

1 day ago

Massive wildfires followed oceanic anoxic events during the Late Devonian Frasnian-Famennian mass extinction Wildfire was a consequence — not a cause — of widespread marine anoxia during the Late Devonian mass extinction.

Massive wildfires followed oceanic anoxic events during the Late Devonian Frasnian-Famennian mass extinction | Science Advances www.science.org/doi/10.1126/... #stableisotopes

Stable Isotope Ecology (CER, Kyoto Univ.)

@stableisotopeecol.bsky.social

5 days ago

Recent progress in the application of organic isotopes in environmental geochemistry of the Anthropocene Naturally occurring stable and radioactive isotopes in organic compounds are extensively utilized in terrestrial, atmospheric, and aquatic environment…

Recent progress in the application of organic isotopes in environmental geochemistry of the Anthropocene #stableisotopes www.sciencedirect.com/science/arti...

Stable Isotope Ecology (CER, Kyoto Univ.)

@stableisotopeecol.bsky.social

5 days ago

Dino Diets Revealed by Isotopes What did dinosaurs such as ‘Spinosaurus’ eat? Analytical techniques settle some decades-long debates.

Dino Diets Revealed by Isotopes | ACS Central Science pubs.acs.org/doi/10.1021/... #stableisotopes

Stable Isotope Ecology (CER, Kyoto Univ.)

@stableisotopeecol.bsky.social

5 days ago

A mineralisation-based method for estimating soil microbial carbon use efficiency Microbial carbon use efficiency (CUE) reflects how microorganisms allocate carbon between mineralisation and biosynthesis, with consequences for soil …

A mineralisation-based method for estimating soil microbial carbon use efficiency #stableisotopes www.sciencedirect.com/science/arti...

Stable Isotope Ecology (CER, Kyoto Univ.)

@stableisotopeecol.bsky.social

5 days ago

Mixotrophy emerges as an optimal strategy in mature waters of the Amazon River plume - Communications Biology There is a transition between four distinct microalgae communities through a mosaic of habitats with different physicochemical conditions associated with the aging of the Amazon River plume, progressi...

Fernández-Carrera, A., Choisnard, N., Wodarg, D. et al. Mixotrophy emerges as an optimal strategy in mature waters of the Amazon River plume. #stableisotopes Commun Biol 9, 434 (2026). doi.org/10.1038/s420...

Stable Isotope Ecology (CER, Kyoto Univ.)

@stableisotopeecol.bsky.social

5 days ago

Drought‐driven lipid deficits in overwintering monarch butterflies revealed by δ2H and fatty acid analysis Eastern populations of monarch butterflies (Danaus plexippus) overwinter in the central trans-volcanic belt of Mexico, relying primarily on lipids accumulated during migration to sustain this several....

Drought‐driven lipid deficits in overwintering monarch butterflies revealed by δ2H and fatty acid analysis - Anparasan - 2026 - Ecosphere #stableisotopes esajournals.onlinelibrary.wiley.com/doi/full/10....

Stable Isotope Ecology (CER, Kyoto Univ.)

@stableisotopeecol.bsky.social

5 days ago

Frontiers | Microbial efficiency enhancement drives carbon sequestration in long-term organic farming systems: linking taxonomic succession to carbon use efficiency Organic farming enhances soil carbon sequestration, which is a critical strategy for climate change mitigation and sustainable agriculture. However, the micr...

Microbial efficiency enhancement drives carbon sequestration in long-term organic farming systems: linking taxonomic succession to carbon use efficiency, doi.org/10.3389/fmicb.2026.1770908, #stableisotopes, Frontiers in Microbiology

Stable Isotope Ecology (CER, Kyoto Univ.)

@stableisotopeecol.bsky.social

5 days ago

Frontiers | Assimilatory N2O reduction by Nostoc sp. strain MS1 isolated from a river: insights from genome and 15N tracer analysis Direct evidence for the assimilation of nitrous oxide (N₂O), a potent greenhouse gas, by freshwater cyanobacteria has been lacking. Here, we report a cyanoba...

Assimilatory N2O reduction by Nostoc sp. strain MS1 isolated from a river: insights from genome and 15N tracer analysis. www.frontiersin.org/journals/mic... #stableisotopes

Stable Isotope Ecology (CER, Kyoto Univ.)

@stableisotopeecol.bsky.social

5 days ago

Biocrusts enhance nitrogen fixation and mineralization, increasing soil nitrogen availability and uptake by dryland shrubs Biocrusts are key components of dryland ecosystems that strongly influence soil nitrogen (N) cycling. In semiarid regions, they often coexist with xer…

Biocrusts enhance nitrogen fixation and mineralization, increasing soil nitrogen availability and uptake by dryland shrubs #stableisotopes www.sciencedirect.com/science/arti...

Stable Isotope Ecology (CER, Kyoto Univ.)

@stableisotopeecol.bsky.social

5 days ago

Application of Isotopic Method to Identify the Sources of Nitrate in Freshwater: Principles, Biases, and Optimizations This review systematically examines the principles and systematic errors of isotope-Bayesian model coupling for nitrate source tracing in aquatic environments, proposes advanced optimization strategi....

Application of Isotopic Method to Identify the Sources of Nitrate in Freshwater: Principles, Biases, and Optimizations - Liu - 2026 - Water Environment Research #stableisotopes onlinelibrary.wiley.com/doi/abs/10.1...

Stable Isotope Ecology (CER, Kyoto Univ.)

@stableisotopeecol.bsky.social

5 days ago

Isotopic Signature of Organic Nitrogen in Authigenic Carbonates: Implications for Dynamic Nitrogen Cycling at Submarine Cold Seeps Organic nitrogen (ON) in seep carbonates records low δ15NON values at both methane and brine seeps δ15NON is largely decoupled from δ13CTOC of organic carbon, indicating variable nitrogen sources...

Isotopic Signature of Organic Nitrogen in Authigenic Carbonates: Implications for Dynamic Nitrogen Cycling at Submarine Cold Seeps - Zhang - 2026 - Journal of Geophysical Research: Oceans #stableisotopes agupubs.onlinelibrary.wiley.com/doi/abs/10.1...

Stable Isotope Ecology (CER, Kyoto Univ.)

@stableisotopeecol.bsky.social

5 days ago

Porewater‐Surface Water Interface Mediates Methanogenesis, Oxidation, and Large Methane Emissions in Mixed Seagrass‐Macroalgae Ecosystems Tidal pumping and seasonal bioturbation jointly regulate CH4 fluxes from porewater exchange Methylotrophic pathway dominates CH4 production, with negligible anaerobic oxidation of CH4 Macroalgae...

Porewater‐Surface Water Interface Mediates Methanogenesis, Oxidation, and Large Methane Emissions in Mixed Seagrass‐Macroalgae Ecosystems - Dai - 2026 - Journal of Geophysical Research: Oceans #stableisotopes agupubs.onlinelibrary.wiley.com/doi/abs/10.1...

Stable Isotope Ecology (CER, Kyoto Univ.)

@stableisotopeecol.bsky.social

5 days ago

Constraining Greenhouse Gas Cycling and Emissions in Africa's Largest Humic Lake Lake Mai Ndombe is supersaturated in CO2 ${\text{CO}}_{2}$, CH4 ${\text{CH}}_{4}$, and N2O ${\mathrm{N}}_{2}\mathrm{O}$, with outgassing fluxes of 375 ± 32 Gg C yr−1, 623 ± 136 Mg C yr−1, and 223 ...

Constraining Greenhouse Gas Cycling and Emissions in Africa's Largest Humic Lake - Barthel - 2026 - Journal of Geophysical Research: Biogeosciences #stableisotopes agupubs.onlinelibrary.wiley.com/doi/full/10....