Articles | Volume 18, issue 11
https://doi.org/10.5194/bg-18-3421-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-18-3421-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
10 Jun 2021
Research article |
| 10 Jun 2021
| 10 Jun 2021
Seasonality of nitrogen sources, cycling, and loading in a New England river discerned from nitrate isotope ratios
Veronica R. Rollinson
CORRESPONDING AUTHOR
Department of Marine Sciences, University of Connecticut, Groton,
06340, USA
Julie Granger
Department of Marine Sciences, University of Connecticut, Groton,
06340, USA
Sydney C. Clark
Department of Earth, Environmental and Planetary Sciences, Brown
University, Providence, 02912, USA
Mackenzie L. Blanusa
Department of Marine Sciences, University of Connecticut, Groton,
06340, USA
Claudia P. Koerting
Department of Marine Sciences, University of Connecticut, Groton,
06340, USA
Jamie M. P. Vaudrey
Department of Marine Sciences, University of Connecticut, Groton,
06340, USA
Lija A. Treibergs
Department of Marine Sciences, University of Connecticut, Groton,
06340, USA
Adirondack Watershed Institute, Paul Smith's College, Paul Smiths,
12970, USA
Holly C. Westbrook
Department of Marine Sciences, University of Connecticut, Groton,
06340, USA
School or the Earth, Ocean and Environment, University of South
Carolina, Columbia, 29208, USA
Catherine M. Matassa
Department of Marine Sciences, University of Connecticut, Groton,
06340, USA
Meredith G. Hastings
Department of Earth, Environmental and Planetary Sciences, Brown
University, Providence, 02912, USA
Craig R. Tobias
Department of Marine Sciences, University of Connecticut, Groton,
06340, USA
Related authors
Josie L. Mottram, Anne M. Gothmann, Maria G. Prokopenko, Austin Cordova, Veronica Rollinson, Katie Dobkowski, and Julie Granger
Biogeosciences, 21, 1071–1091, https://doi.org/10.5194/bg-21-1071-2024, https://doi.org/10.5194/bg-21-1071-2024, 2024
Short summary
Short summary
Knowledge of ancient ocean N cycling can help illuminate past climate change. Using field and lab studies, this work ground-truths a promising proxy for marine N cycling, the N isotope composition of cold-water coral (CWC) skeletons. Our results estimate N turnover in CWC tissue; quantify the isotope effects between CWC tissue, diet, and skeleton; and suggest that CWCs possibly feed mainly on metazoan zooplankton, suggesting that the marine N proxy may be sensitive to the food web structure.
Wendell W. Walters, Masayuki Takeuchi, Danielle E. Blum, Gamze Eris, David Tanner, Weiqi Xu, Jean Rivera-Rios, Fobang Liu, Tianchang Xu, Greg Huey, Justin B. Min, Rodney Weber, Nga L. Ng, and Meredith G. Hastings
EGUsphere, https://doi.org/10.5194/egusphere-2024-3860, https://doi.org/10.5194/egusphere-2024-3860, 2024
Short summary
Short summary
We studied how chemicals released from plants and pollution interact in the atmosphere, affecting air quality and climate. By combining laboratory experiments and chemistry models, we tracked unique chemical fingerprints to understand how nitrogen compounds transform to form particles in the air. Our findings help explain the role of these reactions in pollution and provide tools to improve predictions for cleaner air and better climate policies.
Wendell W. Walters, Masayuki Takeuchi, Nga L. Ng, and Meredith G. Hastings
Geosci. Model Dev., 17, 4673–4687, https://doi.org/10.5194/gmd-17-4673-2024, https://doi.org/10.5194/gmd-17-4673-2024, 2024
Short summary
Short summary
The study introduces a novel chemical mechanism for explicitly tracking oxygen isotope transfer in oxidized reactive nitrogen and odd oxygen using the Regional Atmospheric Chemistry Mechanism, version 2. This model enhances our ability to simulate and compare oxygen isotope compositions of reactive nitrogen, revealing insights into oxidation chemistry. The approach shows promise for improving atmospheric chemistry models and tropospheric oxidation capacity predictions.
Josie L. Mottram, Anne M. Gothmann, Maria G. Prokopenko, Austin Cordova, Veronica Rollinson, Katie Dobkowski, and Julie Granger
Biogeosciences, 21, 1071–1091, https://doi.org/10.5194/bg-21-1071-2024, https://doi.org/10.5194/bg-21-1071-2024, 2024
Short summary
Short summary
Knowledge of ancient ocean N cycling can help illuminate past climate change. Using field and lab studies, this work ground-truths a promising proxy for marine N cycling, the N isotope composition of cold-water coral (CWC) skeletons. Our results estimate N turnover in CWC tissue; quantify the isotope effects between CWC tissue, diet, and skeleton; and suggest that CWCs possibly feed mainly on metazoan zooplankton, suggesting that the marine N proxy may be sensitive to the food web structure.
Jessica M. Burger, Emily Joyce, Meredith G. Hastings, Kurt A. M. Spence, and Katye E. Altieri
Atmos. Chem. Phys., 23, 5605–5622, https://doi.org/10.5194/acp-23-5605-2023, https://doi.org/10.5194/acp-23-5605-2023, 2023
Short summary
Short summary
A seasonal analysis of the nitrogen isotopes of atmospheric nitrate over the remote Southern Ocean reveals that similar natural NOx sources dominate in spring and summer, while winter is representative of background-level conditions. The oxygen isotopes suggest that similar oxidation pathways involving more ozone occur in spring and winter, while the hydroxyl radical is the main oxidant in summer. This work helps to constrain NOx cycling and oxidant budgets in a data-sparse remote marine region.
Claire Bekker, Wendell W. Walters, Lee T. Murray, and Meredith G. Hastings
Atmos. Chem. Phys., 23, 4185–4201, https://doi.org/10.5194/acp-23-4185-2023, https://doi.org/10.5194/acp-23-4185-2023, 2023
Short summary
Short summary
Nitrate is a critical component of the atmosphere that degrades air quality and ecosystem health. We have investigated the nitrogen isotope compositions of nitrate from deposition samples collected across the northeastern United States. Spatiotemporal variability in the nitrogen isotope compositions was found to track with nitrate formation chemistry. Our results highlight that nitrogen isotope compositions may be a robust tool for improving model representation of nitrate chemistry.
Heejeong Kim, Wendell W. Walters, Claire Bekker, Lee T. Murray, and Meredith G. Hastings
Atmos. Chem. Phys., 23, 4203–4219, https://doi.org/10.5194/acp-23-4203-2023, https://doi.org/10.5194/acp-23-4203-2023, 2023
Short summary
Short summary
Atmospheric nitrate has an important impact on human and ecosystem health. We evaluated atmospheric nitrate formation pathways in the northeastern US utilizing oxygen isotope compositions, which indicated a significant difference between the phases of nitrate (i.e., gas vs. particle). Comparing the observations with model simulations indicated that N2O5 hydrolysis chemistry was overpredicted. Our study has important implications for improving atmospheric chemistry model representation.
Wendell W. Walters, Madeline Karod, Emma Willcocks, Bok H. Baek, Danielle E. Blum, and Meredith G. Hastings
Atmos. Chem. Phys., 22, 13431–13448, https://doi.org/10.5194/acp-22-13431-2022, https://doi.org/10.5194/acp-22-13431-2022, 2022
Short summary
Short summary
Atmospheric ammonia and its products are a significant source of urban haze and nitrogen deposition. We have investigated the seasonal source contributions to a mid-sized city in the northeastern US megalopolis utilizing geospatial statistical analysis and novel isotopic constraints, which indicate that vehicle emissions were significant components of the urban-reduced nitrogen budget. Reducing vehicle ammonia emissions should be considered to improve ecosystems and human health.
Jessica M. Burger, Julie Granger, Emily Joyce, Meredith G. Hastings, Kurt A. M. Spence, and Katye E. Altieri
Atmos. Chem. Phys., 22, 1081–1096, https://doi.org/10.5194/acp-22-1081-2022, https://doi.org/10.5194/acp-22-1081-2022, 2022
Short summary
Short summary
The nitrogen (N) isotopic composition of atmospheric nitrate in the Southern Ocean (SO) marine boundary layer (MBL) reveals the importance of oceanic alkyl nitrate emissions as a source of reactive N to the atmosphere. The oxygen isotopic composition suggests peroxy radicals contribute up to 63 % to NO oxidation and that nitrate forms via the OH pathway. This work improves our understanding of reactive N sources and cycling in a remote marine region, a proxy for the pre-industrial atmosphere.
Jiajue Chai, Jack E. Dibb, Bruce E. Anderson, Claire Bekker, Danielle E. Blum, Eric Heim, Carolyn E. Jordan, Emily E. Joyce, Jackson H. Kaspari, Hannah Munro, Wendell W. Walters, and Meredith G. Hastings
Atmos. Chem. Phys., 21, 13077–13098, https://doi.org/10.5194/acp-21-13077-2021, https://doi.org/10.5194/acp-21-13077-2021, 2021
Short summary
Short summary
Nitrous acid (HONO) derived from wildfire emissions plays a key role in controlling atmospheric oxidation chemistry. However, the HONO budget remains poorly constrained. By combining the field-observed concentrations and novel isotopic composition (N and O) of HONO and nitrogen oxides (NOx), we quantitatively constrained the relative contribution of each pathway to secondary HONO production and the relative importance of major atmospheric oxidants (ozone versus peroxy) in aged wildfire smoke.
Guitao Shi, Hongmei Ma, Zhengyi Hu, Zhenlou Chen, Chunlei An, Su Jiang, Yuansheng Li, Tianming Ma, Jinhai Yu, Danhe Wang, Siyu Lu, Bo Sun, and Meredith G. Hastings
The Cryosphere, 15, 1087–1095, https://doi.org/10.5194/tc-15-1087-2021, https://doi.org/10.5194/tc-15-1087-2021, 2021
Short summary
Short summary
It is important to understand atmospheric chemistry over Antarctica under a changing climate. Thus snow collected on a traverse from the coast to Dome A was used to investigate variations in snow chemistry. The non-sea-salt fractions of K+, Mg2+, and Ca2+ are associated with terrestrial inputs, and nssCl− is from HCl. In general, proportions of non-sea-salt fractions of ions to the totals are higher in the interior areas than on the coast, and the proportions are higher in summer than in winter.
Wendell W. Walters, Linlin Song, Jiajue Chai, Yunting Fang, Nadia Colombi, and Meredith G. Hastings
Atmos. Chem. Phys., 20, 11551–11567, https://doi.org/10.5194/acp-20-11551-2020, https://doi.org/10.5194/acp-20-11551-2020, 2020
Short summary
Short summary
This article details new field observations of the nitrogen stable isotopic composition of ammonia emitted from vehicles conducted in the US and China. Vehicle emissions of ammonia may be a significant source to urban regions with important human health and environmental implications. Our measurements have indicated a consistent isotopic signature from vehicle ammonia emissions. The nitrogen isotopic composition of ammonia may be a useful tool for tracking vehicle emissions.
Erika Marín-Spiotta, Rebecca T. Barnes, Asmeret Asefaw Berhe, Meredith G. Hastings, Allison Mattheis, Blair Schneider, and Billy M. Williams
Adv. Geosci., 53, 117–127, https://doi.org/10.5194/adgeo-53-117-2020, https://doi.org/10.5194/adgeo-53-117-2020, 2020
Short summary
Short summary
The geosciences are one of the least diverse disciplines in the United States, despite the field's relevance to people's livelihoods and economies. Bias, discrimination and harassment present serious hurdles to diversifying the field. We summarize research on the factors that contribute to the persistence of hostile climates in the geosciences and other scientific disciplines and provide recommendations for cultural change through the role of mentoring networks and professional associations.
Jiajue Chai, David J. Miller, Eric Scheuer, Jack Dibb, Vanessa Selimovic, Robert Yokelson, Kyle J. Zarzana, Steven S. Brown, Abigail R. Koss, Carsten Warneke, and Meredith Hastings
Atmos. Meas. Tech., 12, 6303–6317, https://doi.org/10.5194/amt-12-6303-2019, https://doi.org/10.5194/amt-12-6303-2019, 2019
Short summary
Short summary
Isotopic analysis offers a potential tool to distinguish between sources and interpret transformation pathways of atmospheric species. We applied recently developed techniques in our lab to characterize the isotopic composition of reactive nitrogen species (NOx, HONO, HNO3, pNO3-) in fresh biomass burning emissions. Intercomparison with other techniques confirms the suitability of our methods, allowing for future applications of our techniques in a variety of environments.
Guitao Shi, Meredith G. Hastings, Jinhai Yu, Tianming Ma, Zhengyi Hu, Chunlei An, Chuanjin Li, Hongmei Ma, Su Jiang, and Yuansheng Li
The Cryosphere, 12, 1177–1194, https://doi.org/10.5194/tc-12-1177-2018, https://doi.org/10.5194/tc-12-1177-2018, 2018
Short summary
Short summary
The deposition and preservation of NO3− across East Antarctica was investigated. On the coast, dry deposition contributes 27–44 % of the NO3− fluxes, and the linear relationship between NO3− and snow accumulation rate suggests a homogeneity of atmospheric NO3− levels. In inland snow, a relatively weak correlation between NO3− and snow accumulation was found, indicating that NO3− is mainly dominated by post-depositional processes. The coexisting ions are generally less influential on snow NO3−.
Nathan J. Chellman, Meredith G. Hastings, and Joseph R. McConnell
The Cryosphere Discuss., https://doi.org/10.5194/tc-2016-163, https://doi.org/10.5194/tc-2016-163, 2016
Revised manuscript not accepted
Short summary
Short summary
This manuscript analyzes the changing sources of nitrate deposition to Greenland since 1760 CE using a dataset consisting of sub-seasonally resolved nitrogen isotopes of nitrate and source tracers. Correlations amongst ion concentration, source tracers, and the δ15N–NO3− provide evidence of the impact of biomass burning and fossil fuel combustion emissions of nitrogen oxides and suggest that oil combustion is the likely driver of increased nitrate concentration in Greenland ice since 1940 CE.
G. Shi, A. M. Buffen, M. G. Hastings, C. Li, H. Ma, Y. Li, B. Sun, C. An, and S. Jiang
Atmos. Chem. Phys., 15, 9435–9453, https://doi.org/10.5194/acp-15-9435-2015, https://doi.org/10.5194/acp-15-9435-2015, 2015
Short summary
Short summary
We evaluate isotopic composition of NO3- in different environments across East Antarctica. At high snow accumulation sites, isotopic ratios are suggestive of preservation of NO3- deposition. At low accumulation sites, isotopes are sensitive to both the loss of NO3- due to photolysis and secondary formation of NO3- within the snow. The imprint of post-depositional alteration is not uniform with depth, making it difficult to predict the isotopic composition at depth from near-surface data alone.
E. D. Sofen, B. Alexander, E. J. Steig, M. H. Thiemens, S. A. Kunasek, H. M. Amos, A. J. Schauer, M. G. Hastings, J. Bautista, T. L. Jackson, L. E. Vogel, J. R. McConnell, D. R. Pasteris, and E. S. Saltzman
Atmos. Chem. Phys., 14, 5749–5769, https://doi.org/10.5194/acp-14-5749-2014, https://doi.org/10.5194/acp-14-5749-2014, 2014
A. K. Hardison, E. A. Canuel, I. C. Anderson, C. R. Tobias, B. Veuger, and M. N. Waters
Biogeosciences, 10, 5571–5588, https://doi.org/10.5194/bg-10-5571-2013, https://doi.org/10.5194/bg-10-5571-2013, 2013
Related subject area
Biogeochemistry: Stable Isotopes & Other Tracers
Stable iron isotope signals indicate a “pseudo-abiotic” process driving deep iron release in methanic sediments
How long does carbon stay in a near-pristine central Amazon forest? An empirical estimate with radiocarbon
No increase is detected and modeled for the seasonal cycle amplitude of δ13C of atmospheric carbon dioxide
Sea ice and mixed layer depth influence on nitrate depletion and associated isotopic effects in the Drake Passage – Weddell Sea region, Southern Ocean
Fungi present distinguishable isotopic signals when grown on glycolytic versus tricarboxylic acid cycle intermediates
Bias in calculating gross nitrification rates in forested catchments using the triple oxygen isotopic composition (Δ17O) of stream nitrate
Position-specific kinetic isotope effects for nitrous oxide: a new expansion of the Rayleigh model
Technical note: A Bayesian mixing model to unravel isotopic data and quantify trace gas production and consumption pathways for time series data – Time-resolved FRactionation And Mixing Evaluation (TimeFRAME)
Separating above-canopy CO2 and O2 measurements into their atmospheric and biospheric signatures
Climatic controls on leaf wax hydrogen isotope ratios in terrestrial and marine sediments along a hyperarid-to-humid gradient
Fractionation of stable carbon isotopes during microbial propionate consumption in anoxic rice paddy soils
Sources and sinks of carbonyl sulfide inferred from tower and mobile atmospheric observations in the Netherlands
Downpour dynamics: outsized impacts of storm events on unprocessed atmospheric nitrate export in an urban watershed
The hidden role of dissolved organic carbon in the biogeochemical cycle of carbon in modern redox-stratified lakes
Biogeochemical processes captured by carbon isotopes in redox-stratified water columns: a comparative study of four modern stratified lakes along an alkalinity gradient
Partitioning of carbon export in the euphotic zone of the oligotrophic South China Sea
Determination of respiration and photosynthesis fractionation factors for atmospheric dioxygen inferred from a vegetation–soil–atmosphere analogue of the terrestrial biosphere in closed chambers
Permafrost degradation and nitrogen cycling in Arctic rivers: insights from stable nitrogen isotope studies
Neodymium budget in the Mediterranean Sea: evaluating the role of atmospheric dusts using a high-resolution dynamical-biogeochemical model
Nitrate isotope investigations reveal future impacts of climate change on nitrogen inputs and cycling in Arctic fjords: Kongsfjorden and Rijpfjorden (Svalbard)
Mineralization of autochthonous particulate organic carbon is a fast channel of organic matter turnover in Germany's largest drinking water reservoir
Carbon isotopic ratios of modern C3 and C4 vegetation on the Indian peninsula and changes along the plant–soil–river continuum – implications for vegetation reconstructions
Controls on nitrite oxidation in the upper Southern Ocean: insights from winter kinetics experiments in the Indian sector
Tracing the source of nitrate in a forested stream showing elevated concentrations during storm events
Intra-skeletal variability in phosphate oxygen isotope composition reveals regional heterothermies in marine vertebrates
Isotopic differences in soil–plant–atmosphere continuum composition and control factors of different vegetation zones on the northern slope of the Qilian Mountains
An analysis of the variability in δ13C in macroalgae from the Gulf of California: indicative of carbon concentration mechanisms and isotope discrimination during carbon assimilation
Summertime productivity and carbon export potential in the Weddell Sea, with a focus on the waters adjacent to Larsen C Ice Shelf
Particulate biogenic barium tracer of mesopelagic carbon remineralization in the Mediterranean Sea (PEACETIME project)
Hydrogen and carbon isotope fractionation factors of aerobic methane oxidation in deep-sea water
Host-influenced geochemical signature in the parasitic foraminifera Hyrrokkin sarcophaga
Comparing modified substrate-induced respiration with selective inhibition (SIRIN) and N2O isotope approaches to estimate fungal contribution to denitrification in three arable soils under anoxic conditions
How are oxygen budgets influenced by dissolved iron and growth of oxygenic phototrophs in an iron-rich spring system? Initial results from the Espan Spring in Fürth, Germany
Stable isotope ratios in seawater nitrate reflect the influence of Pacific water along the northwest Atlantic margin
High-resolution 14C bomb peak dating and climate response analyses of subseasonal stable isotope signals in wood of the African baobab – a case study from Oman
Geographic variability in freshwater methane hydrogen isotope ratios and its implications for global isotopic source signatures
Evaluating the response of δ13C in Haloxylon ammodendron, a dominant C4 species in Asian desert ecosystems, to water and nitrogen addition as well as the availability of its δ13C as an indicator of water use efficiency
Modern silicon dynamics of a small high-latitude subarctic lake
Radium-228-derived ocean mixing and trace element inputs in the South Atlantic
Nitrogen isotopic fractionations during nitric oxide production in an agricultural soil
Silicon uptake and isotope fractionation dynamics by crop species
Barium stable isotopes as a fingerprint of biological cycling in the Amazon River basin
Bottomland hardwood forest growth and stress response to hydroclimatic variation: evidence from dendrochronology and tree ring Δ13C values
N2O isotope approaches for source partitioning of N2O production and estimation of N2O reduction – validation with the 15N gas-flux method in laboratory and field studies
Technical note: Single-shell δ11B analysis of Cibicidoides wuellerstorfi using femtosecond laser ablation MC-ICPMS and secondary ion mass spectrometry
Biogeochemical evidence of anaerobic methane oxidation and anaerobic ammonium oxidation in a stratified lake using stable isotopes
Effects of 238U variability and physical transport on water column 234Th downward fluxes in the coastal upwelling system off Peru
Do degree and rate of silicate weathering depend on plant productivity?
Alpine Holocene tree-ring dataset: age-related trends in the stable isotopes of cellulose show species-specific patterns
Ideas and perspectives: The same carbon behaves like different elements – an insight into position-specific isotope distributions
Susann Henkel, Bo Liu, Michael Staubwasser, Simone A. Kasemann, Anette Meixner, David A. Aromokeye, Michael W. Friedrich, and Sabine Kasten
Biogeosciences, 22, 1673–1696, https://doi.org/10.5194/bg-22-1673-2025, https://doi.org/10.5194/bg-22-1673-2025, 2025
Short summary
Short summary
We intend to unravel iron (Fe) reduction pathways in high-deposition methanic sediments because pools of Fe minerals could stimulate methane oxidation and also generation. Our data from the North Sea show that Fe release takes place mechanistically differently to Fe reduction in shallow sediments, which typically fractionates Fe isotopes. We conclude that fermentation of organic matter involving interspecies electron transfer, partly through conductive Fe oxides, could play an important role.
Ingrid Chanca, Ingeborg Levin, Susan Trumbore, Kita Macario, Jost Lavric, Carlos Alberto Quesada, Alessandro Carioca de Araújo, Cléo Quaresma Dias Júnior, Hella van Asperen, Samuel Hammer, and Carlos A. Sierra
Biogeosciences, 22, 455–472, https://doi.org/10.5194/bg-22-455-2025, https://doi.org/10.5194/bg-22-455-2025, 2025
Short summary
Short summary
Assessing the net carbon (C) budget of the Amazon entails considering the magnitude and timing of C absorption and losses through respiration (transit time of C). Radiocarbon-based estimates of the transit time of C in the Amazon Tall Tower Observatory (ATTO) suggest a change in the transit time from 6 ± 2 years and 18 ± 4 years within 2 years (October 2019 and December 2021, respectively). This variability indicates that only a fraction of newly fixed C can be stored for decades or longer.
Fortunat Joos, Sebastian Lienert, and Sönke Zaehle
Biogeosciences, 22, 19–39, https://doi.org/10.5194/bg-22-19-2025, https://doi.org/10.5194/bg-22-19-2025, 2025
Short summary
Short summary
How plants regulate their exchange of CO2 and water with the atmosphere under global warming is critical for their carbon uptake and their cooling influence. We analyze the isotope ratio of atmospheric CO2 and detect no significant decadal trends in the seasonal cycle amplitude. The data are consistent with the regulation towards leaf CO2 and intrinsic water use efficiency growing proportionally to atmospheric CO2, in contrast to recent suggestions of downregulation of CO2 and water fluxes.
Aymeric Pierre Marie Servettaz, Yuta Isaji, Chisato Yoshikawa, Yanghee Jang, Boo-Keun Khim, Yeongjun Ryu, Daniel M. Sigman, Nanako O. Ogawa, Francisco J. Jiménez-Espejo, and Naohiko Ohkouchi
EGUsphere, https://doi.org/10.5194/egusphere-2024-3687, https://doi.org/10.5194/egusphere-2024-3687, 2024
Short summary
Short summary
Phytoplankton blooms occur after sea ice retreats in the Southern Ocean. In this study we investigate the influence of seasonal cycle of sea ice concentration on nitrate depletion, testing the hypothesis that meltwater release stabilizes the water column and favors nutrient utilization. We find that, at a regional scale, nitrate depletion and vertical mixing are weakly correlated with sea ice cycle. Nitrate depletion is rather linked to other oceanographic processes controlling mixing depth.
Stanislav Jabinski, Vítězslav Kučera, Marek Kopáček, Jan Jansa, and Travis B. Meador
EGUsphere, https://doi.org/10.5194/egusphere-2024-3153, https://doi.org/10.5194/egusphere-2024-3153, 2024
Short summary
Short summary
Microbial production is a key parameter in estimations of organic matter cycling in environmental systems, and fungi play a major role as decomposers. In order to investigate fungal production and turnover times in soils, we incubated fungal pure cultures with isotopically labelled water and bicarbonate to investigate growth signals encoded into lipid biomarkers, which can be applied to improve flux estimates in environmental studies.
Weitian Ding, Urumu Tsunogai, and Fumiko Nakagawa
Biogeosciences, 21, 4717–4722, https://doi.org/10.5194/bg-21-4717-2024, https://doi.org/10.5194/bg-21-4717-2024, 2024
Short summary
Short summary
Past studies have used the Δ17O of stream nitrate to estimate the gross nitrification rates (GNRs) in each forested catchment by approximating the Δ17O value of soil nitrate to be equal to that of stream nitrate. Based on inference and calculation of measured data, we found that this approximation resulted in an overestimated GNR. Therefore, it is essential to clarify and verify the Δ17O NO3− values in forested soils and streams before applying the Δ17O values of stream NO3− to GNR estimation.
Elise D. Rivett, Wenjuan Ma, Nathaniel E. Ostrom, and Eric L. Hegg
Biogeosciences, 21, 4549–4567, https://doi.org/10.5194/bg-21-4549-2024, https://doi.org/10.5194/bg-21-4549-2024, 2024
Short summary
Short summary
Many different processes produce nitrous oxide (N2O), a potent greenhouse gas. Measuring the ratio of heavy and light nitrogen isotopes (15N/14N) for the non-exchangeable central and outer N atoms of N2O helps to distinguish sources of N2O. To accurately calculate the position-specific isotopic preference, we developed an expansion of the widely used Rayleigh model. Application of our new model to simulated and experimental data demonstrates its improved accuracy for analyzing N2O synthesis.
Eliza Harris, Philipp Fischer, Maciej P. Lewicki, Dominika Lewicka-Szczebak, Stephen J. Harris, and Fernando Perez-Cruz
Biogeosciences, 21, 3641–3663, https://doi.org/10.5194/bg-21-3641-2024, https://doi.org/10.5194/bg-21-3641-2024, 2024
Short summary
Short summary
Greenhouse gases are produced and consumed via a number of pathways. Quantifying these pathways helps reduce the climate and environmental footprint of anthropogenic activities. The contribution of the pathways can be estimated from the isotopic composition, which acts as a fingerprint for these pathways. We have developed the Time-resolved FRactionation And Mixing Evaluation (TimeFRAME) model to simplify interpretation and estimate the contribution of different pathways and their uncertainty.
Kim A. P. Faassen, Jordi Vilà-Guerau de Arellano, Raquel González-Armas, Bert G. Heusinkveld, Ivan Mammarella, Wouter Peters, and Ingrid T. Luijkx
Biogeosciences, 21, 3015–3039, https://doi.org/10.5194/bg-21-3015-2024, https://doi.org/10.5194/bg-21-3015-2024, 2024
Short summary
Short summary
The ratio between atmospheric O2 and CO2 can be used to characterize the carbon balance at the surface. By combining a model and observations from the Hyytiälä forest (Finland), we show that using atmospheric O2 and CO2 measurements from a single height provides a weak constraint on the surface CO2 exchange because large-scale processes such as entrainment confound this signal. We therefore recommend always using multiple heights of O2 and CO2 measurements to study surface CO2 exchange.
Nestor Gaviria-Lugo, Charlotte Läuchli, Hella Wittmann, Anne Bernhardt, Patrick Frings, Mahyar Mohtadi, Oliver Rach, and Dirk Sachse
Biogeosciences, 20, 4433–4453, https://doi.org/10.5194/bg-20-4433-2023, https://doi.org/10.5194/bg-20-4433-2023, 2023
Short summary
Short summary
We analyzed how leaf wax hydrogen isotopes in continental and marine sediments respond to climate along one of the strongest aridity gradients in the world, from hyperarid to humid, along Chile. We found that under extreme aridity, the relationship between hydrogen isotopes in waxes and climate is non-linear, suggesting that we should be careful when reconstructing past hydrological changes using leaf wax hydrogen isotopes so as to avoid overestimating how much the climate has changed.
Ralf Conrad and Peter Claus
Biogeosciences, 20, 3625–3635, https://doi.org/10.5194/bg-20-3625-2023, https://doi.org/10.5194/bg-20-3625-2023, 2023
Short summary
Short summary
Knowledge of carbon isotope fractionation is important for the assessment of the pathways involved in the degradation of organic matter. Propionate is an important intermediate. In the presence of sulfate, it was degraded by Syntrophobacter species via acetate to CO2. In the absence of sulfate, it was mainly consumed by Smithella and methanogenic archaeal species via butyrate and acetate to CH4. However, stable carbon isotope fractionation during the degradation process was quite small.
Alessandro Zanchetta, Linda M. J. Kooijmans, Steven van Heuven, Andrea Scifo, Hubertus A. Scheeren, Ivan Mammarella, Ute Karstens, Jin Ma, Maarten Krol, and Huilin Chen
Biogeosciences, 20, 3539–3553, https://doi.org/10.5194/bg-20-3539-2023, https://doi.org/10.5194/bg-20-3539-2023, 2023
Short summary
Short summary
Carbonyl sulfide (COS) has been suggested as a tool to estimate carbon dioxide (CO2) uptake by plants during photosynthesis. However, understanding its sources and sinks is critical to preventing biases in this estimate. Combining observations and models, this study proves that regional sources occasionally influence the measurements at the 60 m tall Lutjewad tower (1 m a.s.l.; 53°24′ N, 6°21′ E) in the Netherlands. Moreover, it estimates nighttime COS fluxes to be −3.0 ± 2.6 pmol m−2 s−1.
Joel T. Bostic, David M. Nelson, and Keith N. Eshleman
Biogeosciences, 20, 2485–2498, https://doi.org/10.5194/bg-20-2485-2023, https://doi.org/10.5194/bg-20-2485-2023, 2023
Short summary
Short summary
Land-use changes can affect water quality. We used tracers of pollution sources and water flow paths to show that an urban watershed exports variable sources during storm events relative to a less developed watershed. Our results imply that changing precipitation patterns combined with increasing urbanization may alter sources of pollution in the future.
Robin Havas, Christophe Thomazo, Miguel Iniesto, Didier Jézéquel, David Moreira, Rosaluz Tavera, Jeanne Caumartin, Elodie Muller, Purificación López-García, and Karim Benzerara
Biogeosciences, 20, 2405–2424, https://doi.org/10.5194/bg-20-2405-2023, https://doi.org/10.5194/bg-20-2405-2023, 2023
Short summary
Short summary
Dissolved organic carbon (DOC) is a reservoir of prime importance in the C cycle of both continental and marine systems. It has also been suggested to influence the past Earth climate but is still poorly characterized in ancient-Earth-like environments. In this paper we show how DOC analyses from modern redox-stratified lakes can evidence specific metabolic reactions and environmental factors and how these can help us to interpret the C cycle of specific periods in the Earth's past.
Robin Havas, Christophe Thomazo, Miguel Iniesto, Didier Jézéquel, David Moreira, Rosaluz Tavera, Jeanne Caumartin, Elodie Muller, Purificación López-García, and Karim Benzerara
Biogeosciences, 20, 2347–2367, https://doi.org/10.5194/bg-20-2347-2023, https://doi.org/10.5194/bg-20-2347-2023, 2023
Short summary
Short summary
We describe the C cycle of four modern stratified water bodies from Mexico, a necessary step to better understand the C cycle of primitive-Earth-like environments, which were dominated by these kinds of conditions. We highlight the importance of local external factors on the C cycle of these systems. Notably, they influence the sensitivity of the carbonate record to environmental changes. We also show the strong C-cycle variability among these lakes and their organic C sediment record.
Yifan Ma, Kuanbo Zhou, Weifang Chen, Junhui Chen, Jin-Yu Terence Yang, and Minhan Dai
Biogeosciences, 20, 2013–2030, https://doi.org/10.5194/bg-20-2013-2023, https://doi.org/10.5194/bg-20-2013-2023, 2023
Short summary
Short summary
We distinguished particulate organic carbon (POC) export fluxes out of the nutrient-depleted layer (NDL) and the euphotic zone. The amount of POC export flux at the NDL base suggests that the NDL could be a hotspot of particle export. The substantial POC export flux at the NDL base challenges traditional concepts that the NDL was limited in terms of POC export. The dominant nutrient source for POC export fluxes should be subsurface nutrients, which was determined by 15N isotopic mass balance.
Clémence Paul, Clément Piel, Joana Sauze, Nicolas Pasquier, Frédéric Prié, Sébastien Devidal, Roxanne Jacob, Arnaud Dapoigny, Olivier Jossoud, Alexandru Milcu, and Amaëlle Landais
Biogeosciences, 20, 1047–1062, https://doi.org/10.5194/bg-20-1047-2023, https://doi.org/10.5194/bg-20-1047-2023, 2023
Short summary
Short summary
To improve the interpretation of the δ18Oatm and Δ17O of O2 in air bubbles in ice cores, we need to better quantify the oxygen fractionation coefficients associated with biological processes. We performed a simplified analogue of the terrestrial biosphere in a closed chamber. We found a respiration fractionation in agreement with the previous estimates at the microorganism scale, and a terrestrial photosynthetic fractionation was found. This has an impact on the estimation of the Dole effect.
Adam Francis, Raja S. Ganeshram, Robyn E. Tuerena, Robert G. M. Spencer, Robert M. Holmes, Jennifer A. Rogers, and Claire Mahaffey
Biogeosciences, 20, 365–382, https://doi.org/10.5194/bg-20-365-2023, https://doi.org/10.5194/bg-20-365-2023, 2023
Short summary
Short summary
Climate change is causing extensive permafrost degradation and nutrient releases into rivers with great ecological impacts on the Arctic Ocean. We focused on nitrogen (N) release from this degradation and associated cycling using N isotopes, an understudied area. Many N species are released at degradation sites with exchanges between species. N inputs from permafrost degradation and seasonal river N trends were identified using isotopes, helping to predict climate change impacts.
Mohamed Ayache, Jean-Claude Dutay, Kazuyo Tachikawa, Thomas Arsouze, and Catherine Jeandel
Biogeosciences, 20, 205–227, https://doi.org/10.5194/bg-20-205-2023, https://doi.org/10.5194/bg-20-205-2023, 2023
Short summary
Short summary
The neodymium (Nd) is one of the most useful tracers to fingerprint water mass provenance. However, the use of Nd is hampered by the lack of adequate quantification of the external sources. Here, we present the first simulation of dissolved Nd concentration and Nd isotopic composition in the Mediterranean Sea using a high-resolution model. We aim to better understand how the various external sources affect the Nd cycle and particularly assess how it is impacted by atmospheric inputs.
Marta Santos-Garcia, Raja S. Ganeshram, Robyn E. Tuerena, Margot C. F. Debyser, Katrine Husum, Philipp Assmy, and Haakon Hop
Biogeosciences, 19, 5973–6002, https://doi.org/10.5194/bg-19-5973-2022, https://doi.org/10.5194/bg-19-5973-2022, 2022
Short summary
Short summary
Terrestrial sources of nitrate are important contributors to the nutrient pool in the fjords of Kongsfjorden and Rijpfjorden in Svalbard during the summer, and they sustain most of the fjord primary productivity. Ongoing tidewater glacier retreat is postulated to favour light limitation and less dynamic circulation in fjords. This is suggested to encourage the export of nutrients to the middle and outer part of the fjord system, which may enhance primary production within and in offshore areas.
Marlene Dordoni, Michael Seewald, Karsten Rinke, Kurt Friese, Robert van Geldern, Jakob Schmidmeier, and Johannes A. C. Barth
Biogeosciences, 19, 5343–5355, https://doi.org/10.5194/bg-19-5343-2022, https://doi.org/10.5194/bg-19-5343-2022, 2022
Short summary
Short summary
Organic matter (OM) turnover into dissolved inorganic carbon (DIC) was investigated by means of carbon isotope mass balances in Germany's largest water reservoir. This includes a metalimnetic oxygen minimum (MOM). Autochthonous particulate organic carbon (POC) was the main contributor to DIC, with rates that were highest for the MOM. Generally low turnover rates outline the environmental fragility of this water body in the case that OM loads increase due to storm events or land use changes.
Frédérique M. S. A. Kirkels, Hugo J. de Boer, Paulina Concha Hernández, Chris R. T. Martes, Marcel T. J. van der Meer, Sayak Basu, Muhammed O. Usman, and Francien Peterse
Biogeosciences, 19, 4107–4127, https://doi.org/10.5194/bg-19-4107-2022, https://doi.org/10.5194/bg-19-4107-2022, 2022
Short summary
Short summary
The distinct carbon isotopic values of C3 and C4 plants are widely used to reconstruct past hydroclimate, where more C3 plants reflect wetter and C4 plants drier conditions. Here we examine the impact of regional hydroclimatic conditions on plant isotopic values in the Godavari River basin, India. We find that it is crucial to identify regional plant isotopic values and consider drought stress, which introduces a bias in C3 / C4 plant estimates and associated hydroclimate reconstructions.
Mhlangabezi Mdutyana, Tanya Marshall, Xin Sun, Jessica M. Burger, Sandy J. Thomalla, Bess B. Ward, and Sarah E. Fawcett
Biogeosciences, 19, 3425–3444, https://doi.org/10.5194/bg-19-3425-2022, https://doi.org/10.5194/bg-19-3425-2022, 2022
Short summary
Short summary
Nitrite-oxidizing bacteria in the winter Southern Ocean show a high affinity for nitrite but require a minimum (i.e., "threshold") concentration before they increase their rates of nitrite oxidation significantly. The classic Michaelis–Menten model thus cannot be used to derive the kinetic parameters, so a modified equation was employed that also yields the threshold nitrite concentration. Dissolved iron availability may play an important role in limiting nitrite oxidation.
Weitian Ding, Urumu Tsunogai, Fumiko Nakagawa, Takashi Sambuichi, Hiroyuki Sase, Masayuki Morohashi, and Hiroki Yotsuyanagi
Biogeosciences, 19, 3247–3261, https://doi.org/10.5194/bg-19-3247-2022, https://doi.org/10.5194/bg-19-3247-2022, 2022
Short summary
Short summary
Excessive leaching of nitrate from forested catchments during storm events degrades water quality and causes eutrophication in downstream areas. Thus, tracing the source of nitrate increase during storm events in forested streams is important for sustainable forest management. Based on the isotopic compositions of stream nitrate, including Δ17O, this study clarifies that the source of stream nitrate increase during storm events was soil nitrate in the riparian zone.
Nicolas Séon, Romain Amiot, Guillaume Suan, Christophe Lécuyer, François Fourel, Fabien Demaret, Arnauld Vinçon-Laugier, Sylvain Charbonnier, and Peggy Vincent
Biogeosciences, 19, 2671–2681, https://doi.org/10.5194/bg-19-2671-2022, https://doi.org/10.5194/bg-19-2671-2022, 2022
Short summary
Short summary
We analysed the oxygen isotope composition of bones and teeth of four marine species possessing regional heterothermies. We observed a consistent link between oxygen isotope composition and temperature heterogeneities recorded by classical methods. This opens up new perspectives on the determination of the thermoregulatory strategies of extant marine vertebrates where conventional methods are difficult to apply, but also allows us to investigate thermophysiologies of extinct vertebrates.
Yuwei Liu, Guofeng Zhu, Zhuanxia Zhang, Zhigang Sun, Leilei Yong, Liyuan Sang, Lei Wang, and Kailiang Zhao
Biogeosciences, 19, 877–889, https://doi.org/10.5194/bg-19-877-2022, https://doi.org/10.5194/bg-19-877-2022, 2022
Short summary
Short summary
We took the water cycle process of soil–plant–atmospheric precipitation as the research objective. In the water cycle of soil–plant–atmospheric precipitation, precipitation plays the main controlling role. The main source of replenishment for alpine meadow plants is precipitation and alpine meltwater; the main source of replenishment for forest plants is soil water; and the plants in the arid foothills mainly use groundwater.
Roberto Velázquez-Ochoa, María Julia Ochoa-Izaguirre, and Martín Federico Soto-Jiménez
Biogeosciences, 19, 1–27, https://doi.org/10.5194/bg-19-1-2022, https://doi.org/10.5194/bg-19-1-2022, 2022
Short summary
Short summary
Our research is the first approximation to understand the δ13C macroalgal variability in one of the most diverse marine ecosystems in the world, the Gulf of California. The life-form is the principal cause of δ13C macroalgal variability, mainly taxonomy. However, changes in habitat characteristics and environmental conditions also influence the δ13C macroalgal variability. The δ13C macroalgae is indicative of carbon concentration mechanisms and isotope discrimination during carbon assimilation.
Raquel F. Flynn, Thomas G. Bornman, Jessica M. Burger, Shantelle Smith, Kurt A. M. Spence, and Sarah E. Fawcett
Biogeosciences, 18, 6031–6059, https://doi.org/10.5194/bg-18-6031-2021, https://doi.org/10.5194/bg-18-6031-2021, 2021
Short summary
Short summary
Biological activity in the shallow Weddell Sea affects the biogeochemistry of recently formed deep waters. To investigate the drivers of carbon and nutrient export, we measured rates of primary production and nitrogen uptake, characterized the phytoplankton community, and estimated nutrient depletion ratios across the under-sampled western Weddell Sea in mid-summer. Carbon export was highest at the ice shelves and was determined by a combination of physical, chemical, and biological factors.
Stéphanie H. M. Jacquet, Christian Tamburini, Marc Garel, Aurélie Dufour, France Van Vambeke, Frédéric A. C. Le Moigne, Nagib Bhairy, and Sophie Guasco
Biogeosciences, 18, 5891–5902, https://doi.org/10.5194/bg-18-5891-2021, https://doi.org/10.5194/bg-18-5891-2021, 2021
Short summary
Short summary
We compared carbon remineralization rates (MRs) in the western and central Mediterranean Sea in late spring during the PEACETIME cruise, as assessed using the barium tracer. We reported higher and deeper (up to 1000 m depth) MRs in the western basin, potentially sustained by an additional particle export event driven by deep convection. The central basin is the site of a mosaic of blooming and non-blooming water masses and showed lower MRs that were restricted to the upper mesopelagic layer.
Shinsuke Kawagucci, Yohei Matsui, Akiko Makabe, Tatsuhiro Fukuba, Yuji Onishi, Takuro Nunoura, and Taichi Yokokawa
Biogeosciences, 18, 5351–5362, https://doi.org/10.5194/bg-18-5351-2021, https://doi.org/10.5194/bg-18-5351-2021, 2021
Short summary
Short summary
Hydrogen and carbon isotope ratios of methane as well as the relevant biogeochemical parameters and microbial community compositions in hydrothermal plumes in the Okinawa Trough were observed. We succeeded in simultaneously determining hydrogen and carbon isotope fractionation factors associated with aerobic oxidation of methane in seawater (εH = 49.4 ± 5.0 ‰, εC = 5.2 ± 0.4 ‰) – the former being the first of its kind ever reported.
Nicolai Schleinkofer, David Evans, Max Wisshak, Janina Vanessa Büscher, Jens Fiebig, André Freiwald, Sven Härter, Horst R. Marschall, Silke Voigt, and Jacek Raddatz
Biogeosciences, 18, 4733–4753, https://doi.org/10.5194/bg-18-4733-2021, https://doi.org/10.5194/bg-18-4733-2021, 2021
Short summary
Short summary
We have measured the chemical composition of the carbonate shells of the parasitic foraminifera Hyrrokkin sarcophaga in order to test if it is influenced by the host organism (bivalve or coral). We find that both the chemical and isotopic composition is influenced by the host organism. For example strontium is enriched in foraminifera that grew on corals, whose skeleton is built from aragonite, which is naturally enriched in strontium compared to the bivalves' calcite shell.
Lena Rohe, Traute-Heidi Anderson, Heinz Flessa, Anette Goeske, Dominika Lewicka-Szczebak, Nicole Wrage-Mönnig, and Reinhard Well
Biogeosciences, 18, 4629–4650, https://doi.org/10.5194/bg-18-4629-2021, https://doi.org/10.5194/bg-18-4629-2021, 2021
Short summary
Short summary
This is the first experimental setup combining a complex set of methods (microbial inhibitors and isotopic approaches) to differentiate between N2O produced by fungi or bacteria during denitrification in three soils. Quantifying the fungal fraction with inhibitors was not successful due to large amounts of uninhibited N2O production. All successful methods suggested a small or missing fungal contribution. Artefacts occurring with microbial inhibition to determine N2O fluxes are discussed.
Inga Köhler, Raul E. Martinez, David Piatka, Achim J. Herrmann, Arianna Gallo, Michelle M. Gehringer, and Johannes A. C. Barth
Biogeosciences, 18, 4535–4548, https://doi.org/10.5194/bg-18-4535-2021, https://doi.org/10.5194/bg-18-4535-2021, 2021
Short summary
Short summary
We investigated how high Fe(II) levels influence the O2 budget of a circum-neutral Fe(II)-rich spring and if a combined study of dissolved O (DO) and its isotopic composition can help assess this effect. We showed that dissolved Fe(II) can exert strong effects on the δ18ODO even though a constant supply of atmospheric O2 occurs. In the presence of photosynthesis, direct effects of Fe oxidation become masked. Critical Fe(II) concentrations indirectly control the DO by enhancing photosynthesis.
Owen A. Sherwood, Samuel H. Davin, Nadine Lehmann, Carolyn Buchwald, Evan N. Edinger, Moritz F. Lehmann, and Markus Kienast
Biogeosciences, 18, 4491–4510, https://doi.org/10.5194/bg-18-4491-2021, https://doi.org/10.5194/bg-18-4491-2021, 2021
Short summary
Short summary
Pacific water flowing eastward through the Canadian Arctic plays an important role in redistributing nutrients to the northwest Atlantic Ocean. Using samples collected from northern Baffin Bay to the southern Labrador Shelf, we show that stable isotopic ratios in seawater nitrate reflect the fraction of Pacific to Atlantic water. These results provide a new framework for interpreting patterns of nitrogen isotopic variability recorded in modern and archival organic materials in the region.
Franziska Slotta, Lukas Wacker, Frank Riedel, Karl-Uwe Heußner, Kai Hartmann, and Gerhard Helle
Biogeosciences, 18, 3539–3564, https://doi.org/10.5194/bg-18-3539-2021, https://doi.org/10.5194/bg-18-3539-2021, 2021
Short summary
Short summary
The African baobab is a challenging climate and environmental archive for its semi-arid habitat due to dating uncertainties and parenchyma-rich wood anatomy. Annually resolved F14C data of tree-ring cellulose (1941–2005) from a tree in Oman show the annual character of the baobab’s growth rings but were up to 8.8 % lower than expected for 1964–1967. Subseasonal δ13C and δ18O patterns reveal years with low average monsoon rain as well as heavy rainfall events from pre-monsoonal cyclones.
Peter M. J. Douglas, Emerald Stratigopoulos, Sanga Park, and Dawson Phan
Biogeosciences, 18, 3505–3527, https://doi.org/10.5194/bg-18-3505-2021, https://doi.org/10.5194/bg-18-3505-2021, 2021
Short summary
Short summary
Hydrogen isotopes could be a useful tool to help resolve the geographic distribution of methane emissions from freshwater environments. We analyzed an expanded global dataset of freshwater methane hydrogen isotope ratios and found significant geographic variation linked to water isotopic composition. This geographic variability could be used to resolve changing methane fluxes from freshwater environments and provide more accurate estimates of the relative balance of global methane sources.
Zixun Chen, Xuejun Liu, Xiaoqing Cui, Yaowen Han, Guoan Wang, and Jiazhu Li
Biogeosciences, 18, 2859–2870, https://doi.org/10.5194/bg-18-2859-2021, https://doi.org/10.5194/bg-18-2859-2021, 2021
Short summary
Short summary
δ13C in plants is a sensitive long-term indicator of physiological acclimatization. The present study suggests that precipitation change and increasing atmospheric N deposition have little impact on δ13C of H. ammodendron, a dominant plant in central Asian deserts, but affect its gas exchange. In addition, this study shows that δ13C of H. ammodendron could not indicate its water use efficiency (WUE), suggesting that whether δ13C of C4 plants indicates WUE is species-specific.
Petra Zahajská, Carolina Olid, Johanna Stadmark, Sherilyn C. Fritz, Sophie Opfergelt, and Daniel J. Conley
Biogeosciences, 18, 2325–2345, https://doi.org/10.5194/bg-18-2325-2021, https://doi.org/10.5194/bg-18-2325-2021, 2021
Short summary
Short summary
The drivers of high accumulation of single-cell siliceous algae (diatoms) in a high-latitude lake have not been fully characterized before. We studied silicon cycling of the lake through water, radon, silicon, and stable silicon isotope balances. Results showed that groundwater brings 3 times more water and dissolved silica than the stream inlet. We demonstrate that groundwater discharge and low sediment deposition have driven the high diatom accumulation in the studied lake in the past century.
Yu-Te Hsieh, Walter Geibert, E. Malcolm S. Woodward, Neil J. Wyatt, Maeve C. Lohan, Eric P. Achterberg, and Gideon M. Henderson
Biogeosciences, 18, 1645–1671, https://doi.org/10.5194/bg-18-1645-2021, https://doi.org/10.5194/bg-18-1645-2021, 2021
Short summary
Short summary
The South Atlantic near 40° S is one of the high-productivity and most dynamic nutrient regions in the oceans, but the sources and fluxes of trace elements (TEs) to this region remain unclear. This study investigates seawater Ra-228 and provides important constraints on ocean mixing and dissolved TE fluxes to this region. Vertical mixing is a more important source than aeolian or shelf inputs in this region, but particulate or winter deep-mixing inputs may be required to balance the TE budgets.
Zhongjie Yu and Emily M. Elliott
Biogeosciences, 18, 805–829, https://doi.org/10.5194/bg-18-805-2021, https://doi.org/10.5194/bg-18-805-2021, 2021
Short summary
Short summary
In this study, we demonstrated distinct nitrogen isotope effects for nitric oxide (NO) production from major microbial and chemical NO sources in an agricultural soil. These results highlight characteristic bond-forming and breaking mechanisms associated with microbial and chemical NO production and implicate that simultaneous isotopic analyses of NO and nitrous oxide (N2O) can lead to unprecedented insights into the sources and processes controlling NO and N2O emissions from agricultural soils.
Daniel A. Frick, Rainer Remus, Michael Sommer, Jürgen Augustin, Danuta Kaczorek, and Friedhelm von Blanckenburg
Biogeosciences, 17, 6475–6490, https://doi.org/10.5194/bg-17-6475-2020, https://doi.org/10.5194/bg-17-6475-2020, 2020
Short summary
Short summary
Silicon is taken up by some plants to increase structural stability and to develop stress resistance and is rejected by others. To explore the underlying mechanisms, we used the stable isotopes of silicon that shift in their relative abundance depending on the biochemical transformation involved. On species with a rejective (tomato, mustard) and active (wheat) uptake mechanism, grown in hydroculture, we found that the transport of silicic acid is controlled by the precipitation of biogenic opal.
Quentin Charbonnier, Julien Bouchez, Jérôme Gaillardet, and Éric Gayer
Biogeosciences, 17, 5989–6015, https://doi.org/10.5194/bg-17-5989-2020, https://doi.org/10.5194/bg-17-5989-2020, 2020
Short summary
Short summary
The abundance and isotope composition of the trace metal barium (Ba) allows us to track and quantify nutrient cycling throughout the Amazon Basin. In particular, we show that the Ba biological fingerprint evolves from that of a strong net nutrient uptake in the mountainous area of the Andes towards efficient nutrient recycling on the plains of the Lower Amazon. Our study highlights the fact that the geochemical signature of rock-derived nutrients transported by the Amazon is scarred by life.
Ajinkya G. Deshpande, Thomas W. Boutton, Ayumi Hyodo, Charles W. Lafon, and Georgianne W. Moore
Biogeosciences, 17, 5639–5653, https://doi.org/10.5194/bg-17-5639-2020, https://doi.org/10.5194/bg-17-5639-2020, 2020
Short summary
Short summary
Wetland forests in the southern USA are threatened by changing climate and human-induced pressures. We used tree ring widths and C isotopes as indicators of forest growth and physiological stress, respectively, and compared these to past climate data. We observed that vegetation growing in the drier patches is susceptible to stress, while vegetation growth and physiology in wetter patches is less sensitive to unfavorable environmental conditions, highlighting the importance of optimal wetness.
Dominika Lewicka-Szczebak, Maciej Piotr Lewicki, and Reinhard Well
Biogeosciences, 17, 5513–5537, https://doi.org/10.5194/bg-17-5513-2020, https://doi.org/10.5194/bg-17-5513-2020, 2020
Short summary
Short summary
We present the first validation of N2O isotopic approaches for estimating N2O source pathways and N2O reduction. These approaches are widely used for tracing soil nitrogen cycling, but the results of these estimations are very uncertain. Here we report the results from parallel treatments allowing for precise validation of these approaches, and we propose the best strategies for results interpretation, including the new idea of an isotope model integrating three isotopic signatures of N2O.
Markus Raitzsch, Claire Rollion-Bard, Ingo Horn, Grit Steinhoefel, Albert Benthien, Klaus-Uwe Richter, Matthieu Buisson, Pascale Louvat, and Jelle Bijma
Biogeosciences, 17, 5365–5375, https://doi.org/10.5194/bg-17-5365-2020, https://doi.org/10.5194/bg-17-5365-2020, 2020
Short summary
Short summary
The isotopic composition of boron in carbonate shells of marine unicellular organisms is a popular tool to estimate seawater pH. Usually, many shells need to be dissolved and measured for boron isotopes, but the information on their spatial distribution is lost. Here, we investigate two techniques that allow for measuring boron isotopes within single shells and show that they yield robust mean values but provide additional information on the heterogeneity within and between single shells.
Florian Einsiedl, Anja Wunderlich, Mathieu Sebilo, Ömer K. Coskun, William D. Orsi, and Bernhard Mayer
Biogeosciences, 17, 5149–5161, https://doi.org/10.5194/bg-17-5149-2020, https://doi.org/10.5194/bg-17-5149-2020, 2020
Short summary
Short summary
Nitrate pollution of freshwaters and methane emissions into the atmosphere are crucial factors in deteriorating the quality of drinking water and in contributing to global climate change. Here, we report vertical concentration and stable isotope profiles of CH4, NO3-, NO2-, and NH4+ in the water column of Fohnsee (southern Bavaria, Germany) that may indicate linkages between nitrate-dependent anaerobic methane oxidation and the anaerobic oxidation of ammonium.
Ruifang C. Xie, Frédéric A. C. Le Moigne, Insa Rapp, Jan Lüdke, Beat Gasser, Marcus Dengler, Volker Liebetrau, and Eric P. Achterberg
Biogeosciences, 17, 4919–4936, https://doi.org/10.5194/bg-17-4919-2020, https://doi.org/10.5194/bg-17-4919-2020, 2020
Short summary
Short summary
Thorium-234 (234Th) is widely used to study carbon fluxes from the surface ocean to depth. But few studies stress the relevance of oceanic advection and diffusion on the downward 234Th fluxes in nearshore environments. Our study in offshore Peru showed strong temporal variations in both the importance of physical processes on 234Th flux estimates and the oceanic residence time of 234Th, whereas salinity-derived seawater 238U activities accounted for up to 40 % errors in 234Th flux estimates.
Ralf A. Oeser and Friedhelm von Blanckenburg
Biogeosciences, 17, 4883–4917, https://doi.org/10.5194/bg-17-4883-2020, https://doi.org/10.5194/bg-17-4883-2020, 2020
Short summary
Short summary
We present a novel strategy to decipher the relative impact of biogenic and abiotic drivers of weathering. We parameterized the nutrient fluxes in four ecosystems along a climate and vegetation gradient situated on the Chilean Coastal Cordillera. We investigated how nutrient demand by plants drives weathering. We found that the increase in biomass nutrient demand is accommodated by faster nutrient recycling rather than an increase in the weathering–release rates.
Tito Arosio, Malin M. Ziehmer, Kurt Nicolussi, Christian Schlüchter, and Markus Leuenberger
Biogeosciences, 17, 4871–4882, https://doi.org/10.5194/bg-17-4871-2020, https://doi.org/10.5194/bg-17-4871-2020, 2020
Short summary
Short summary
Stable isotopes in tree-ring cellulose are tools for climatic reconstructions, but interpretation is challenging due to nonclimate trends. We analyzed the tree-age trends in tree-ring isotopes of deciduous larch and evergreen cembran pine. Samples covering the whole Holocene were collected at the tree line in the Alps. For cambial ages over 100 years, we prove the absence of age trends in δD, δ18O, and δ13C for both species. For lower cambial ages, trends differ for each isotope and species.
Yuyang He, Xiaobin Cao, and Huiming Bao
Biogeosciences, 17, 4785–4795, https://doi.org/10.5194/bg-17-4785-2020, https://doi.org/10.5194/bg-17-4785-2020, 2020
Short summary
Short summary
Different carbon sites in a large organic molecule have different isotope compositions. Different carbon sites may not have the chance to exchange isotopes at all. The lack of appreciation of this notion might be blamed for an unsettled debate on the thermodynamic state of an organism. Here we demonstrate using minerals, N2O, and acetic acid that the dearth of exchange among different carbon sites renders them as independent as if they were different elements in organic molecules.
Cited articles
4500-NH3 NITROGEN (AMMONIA), Standard Methods For the
Examination of Water and Wastewater,
https://doi.org/10.2105/SMWW.2882.087, 2018.
4500-NO3− NITROGEN (NITRATE), Standard Methods For the
Examination of Water and Wastewater,
https://doi.org/10.2105/SMWW.2882.089, 2018.
4500-P PHOSPHORUS, Standard Methods For the Examination of Water and
Wastewater, https://doi.org/10.2105/SMWW.2882.093, 2018.
Amundson, R., Austin, A. T., Schuur, E. A. G., Yoo, K., Matzek, V., Kendall,
C., Uebersax, A., Brenner, D., and Baisden, W. T.: Global patterns of the
isotopic composition of soil and plant nitrogen, Global Biogeochem. Cy.,
17, https://doi.org/10.1029/2002GB001903, 2003.
Andersson, K. K. and Hooper, A. B.: O2 and H2O are each the source of one O
in NO2 produced from NH3 by Nitrosomonas: 15N-NMR evidence, FEBS Lett.,
164, 236–240, 1983.
Arar, E. and Collins, G.: In vitro determination of Chlorophyll a and
pheophytin in marine freshwater and algae by fluoresecence, National
Exposure Research Laboratory, Cincinnatri, USA, 22 pp., 1997.
Barnes, R. T. and Raymond, P.: The contribution of agricultural and urban
activities to inorganic carbon fluxes within temperate watersheds, Chem.
Geol., 266, 318–327, 2009.
Barnes, R. T., Raymond, P. A., and Casciotti, K. L.: Dual isotope analyses
indicate efficient processing of atmospheric nitrate by forested watersheds
in the northeastern U.S, Biogeochemistry, 90, 15–27, 2008.
Baron, J. S., Hall, E. K., Nolan, B. T., Finlay, J. C., Bernhardt, E. S.,
Harrison, J. A., Chan, F., and Boyer, E. W.: The interactive effects of
excess reactive nitrogen and climate change on aquatic ecosystems and water
resources of the United States, Biogeochemistry, 114, 71–92, 2013.
Beale, B. M. L.: Some uses of computers in operational research,
Industrielle Organisation, 31, 27–28, 1962.
Berezina, N. and Golubkov, S.: Effect of drifting macroalgae Cladophora
glomerata on benthic community dynamics in the easternmost Baltic Sea, J.
Mar. Syst., 74, S80–S85, https://doi.org/10.1016/j.jmarsys.2008.03.027, 2008.
Böhlke, J. K.: Sources, transport, and reaction of nitrate in ground
water, Residence times and nitrate transport in ground water discharging
to streams in the Chesapeake Bay Watershed, US Geological Survey
Water-Resources Investigations Report 03-4035, US Geological Survey, New Cumberland, Pennsylvania, USA, 215 pp.,
2003.
Böhlke, J. K., Smith, R. L., and Miller, D. N.: Ammonium transport and
reaction in contaminated groundwater: Application of isotope tracers and
isotope fractionation studies, Water Resour. Res., 42, W05411, https://doi.org/10.1029/2005WR004349, 2006.
Böhlke, J. K., Hatzinger, P. B., Sturchio, N. C., Gu, B., Abbene, I., and
Mroczkowski, S. J.: Atacama Perchlorate as an Agricultural Contaminant in
Groundwater: Isotopic and Chronologic Evidence from Long Island, New York,
Environ. Sci. Technol., 43, 5619–5625, 2009.
Boshers, D. S., Granger, J., Tobias, C. R., Böhlke, J. K., and
Smith, R. L.: Constraining the Oxygen Isotopic Composition of Nitrate
Produced by Nitrification, Environ. Sci. Technol., 53, 1206–1216, 2019.
Braman, R. S. and Hendrix, S. A.: Nanogram nitrite and nitrate determination
in environmental and biological materials by vanadium (III) reduction with
chemiluminescence detection, Anal. Chem., 61, 2715–2718, 1989.
Brandes, J. A. and Devol, A. H.: Isotopic fractionation of oxygen and
nitrogen in coastal marine sediments, Geochim. Cosmochim. Ac., 61,
1793–1801, https://doi.org/10.1016/S0016-7037(97)00041-0, 1997.
Brookshire, E. N. J., Valett, H. M., Thomas, S. A., and Webster, J. R.:
Coupled cycling of dissolved organic nitrogen and carbon in a forest stream,
Ecology, 86, 2487–2496, 2005.
Buchwald, C. and Casciotti, K. L.: Oxygen isotopic fractionation and
exchange during bacterial nitrite oxidation, Limnol. Oceanogr., 55,
1064–1074, 2010.
Casciotti, K., Trull, T. W., Glover, D. M., and Davies, D.: Constraints
on nitrogen cycling in the subtropical North Pacific Station ALOHA from
isotopic measurements of nitrate and particulate nitrogen, Deep Sea Res.,
55, 1661, https://doi.org/10.1016/j.dsr2.2008.04.017, 2008.
Casciotti, K. L.: Nitrogen and Oxygen Isotopic Studies of the Marine
Nitrogen Cycle, Annu. Rev. Mar. Sci., 8, 379–407, 2016.
Casciotti, K. L., Sigman, D. M., Hastings, M. G., Böhlke, J. K., and
Hilkert, A.: Measurement of the oxygen isotopic composition of nitrate in
seawater and freshwater using the denitrifier method, Anal. Chem., 74, 4905,
https://doi.org/10.1021/ac020113w, 2002.
D'Avanzo, C. and Kremer, J. N.: Diel oxygen dynamics and anoxic events in an
eutrophic estuary of Waquoit Bay, Massachusetts, Estuaries, 17, 131–139,
1994.
Deutsch, B., Liskow, I., Kahle, P., and Voss, M.: Variations in the δ15N and δ18O values of nitrate in drainage water of two fertilized
fields in Mecklenburg-Vorpommern (Germany), Aquat. Sci., 67, 156–165, 2005.
Dickerman, D. C. and Bell, R. W.: Hydrogeology, Water Quality, and
Ground-water-development Alternatives in the Lower Wood River Ground-water
Reservoir, Rhode Island, US Department of the Interior, US Geological
Survey, Providence, Rhode Island, USA, 92 pp., 1993.
Dickerman, D., Bell, R., Mulvey, K., Peterman, E., and Russell, J.:
Geohydrologic data for the upper Wood River ground-water reservoir, Rhode
Island, Rhode Island Water Resources Board Water Information Series Report,
Providence, RI, USA, 274 pp.,
1989.
Dillingham, T. P.: The Pawcatuck River Estuary and Little Narragansett Bay:
An Interstate Management Plan: Adopted July 14, 1992, Rhode Island Coastal Resources Management Council
Connecticut Department of Environmental Protection
Stonington, Connecticut and Westerly Rhode Island, 1993.
Divers, M., Elliott, E., and Bain, D.: Quantification of Nitrate Sources to
an Urban Stream Using Dual Nitrate Isotopes, Environ. Sci. Technol., 48, 10580-7, https://doi.org/10.1021/es404880j, 2014.
Dodds, W. K. and Gudder, D. A.: The Ecology Of Cladophora, J. Phycol., 28,
415–427, 1992.
Dubrovsky, N. M., Burow, K. R., Clark, G. M., Gronberg, J. M., Hamilton, P. A.,
Hitt, K. J., Mueller, D. K., Munn, M. D., Nolan, B. T., Puckett, L. J., Rupert,
M. G., Short, T. M., Spahr, N. E., Sprague, L. A., and Wilber, W. G.: The quality
of our Nation's waters – Nutrients in the Nation's streams and groundwater,
1992–2004, US Geological Survey Circular 1350, available at: http://water.usgs.gov/nawqa/nutrients/pubs/circ1350 (last access: 9 March 2020), 2010.
Elwood, J. W. and Turner, R. R.: Streams: Water Chemistry and Ecology, in:
Analysis of Biogeochemical Cycling Processes in Walker Branch Watershed, edited by:
Johnson, D. W. and Van Hook, R. I., Springer, New York, USA,
301–350, 1989.
Ensign, S. H. and Doyle, M. W.: Nutrient spiraling in streams and river
networks, J. Geophys. Res., 111, G04009, https://doi.org/10.1029/2005JG000114, 2006.
Fang, Y., Koba, K., Makabe, A., Zhu, F., Fan, S., and Yoh, M.: Low
δ18O Values of Nitrate Produced from Nitrification in Temperate Forest
Soils, Environ. Sci. Technol., 46, 8723–8730, 2012.
Froelich, P. N.: Kinetic control of dissolved phosphate in natural rivers
and estuaries: A primer on the phosphate buffer mechanism, Limnol.
Oceanogr., 33, 649–668, 1988.
Fulweiler, R. W. and Nixon, S. W.: Export of Nitrogen, Phosphorus, and
Suspended Solids from a Southern New England Watershed to Little
Narragansett Bay, Biogeochemistry, 76, 567–593, 2005.
Garside, C.: A chemiluminescent technique for the determination of nanomolar
concentrations of nitrate and nitrite in seawater, Mar. Chem., 11, 159–167,
1982.
Granger, J. and Wankel, S. D.: Isotopic overprinting of nitrification on
denitrification as a ubiquitous and unifying feature of environmental
nitrogen cycling, P. Natl. Acad. Sci. USA, 113, 6391–6400,
https://doi.org/10.1073/pnas.1601383113, 2016.
Granger, J., Sigman, D. M., Needoba, J. A., and Harrison, P. J.: Coupled
nitrogen and oxygen isotope fractionation of nitrate during assimilation by
cultures of marine phytoplankton, Limnol. Oceanogr., 49, 1763–1773, 2004.
Granger, J., Prokopenko, M. G., Sigman, D. M., Mordy, C. W., Morse, Z. M.,
Morales, L. V., Sambrotto, R. N., and Plessen, B.: Coupled
nitrification-denitrification in sediment of the eastern Bering Sea shelf
leads to 15N enrichment of fixed N in shelf waters, J. Geophys. Res., 116, C11006, https://doi.org/10.1029/2010JC006751,
2011.
Granger, J., Prokopenko, M. G., Mordy, C. W., and Sigman, D. M.: The
proportion of remineralized nitrate on the ice-covered eastern Bering Sea
shelf evidenced from the oxygen isotope ratio of nitrate, Global Biogeochem.
Cy., 27, 962–971, 2013.
Grasshoff, K., Kremling, K., and Ehrhardt, M.: Methods of Seawater Analysis,
Third Edition, Wiley, New York, USA, https://doi.org/10.1002/9783527613984, 1999.
Green, C. T., Fisher, L. H., and Bekins, B. A.: Nitrogen Fluxes through
Unsaturated Zones in Five Agricultural Settings across the United States, J.
Environ. Qual., 37, 1073–1085, 2008.
Gruber, N. and Galloway, J. N.: An Earth-system perspective of the global
nitrogen cycle, Nature, 451, 293–296,
https://doi.org/10.1038/nature06592, 2008.
Harvey, J. W., Böhlke, J. K., Voytek, M. A., Scott, D., and Tobias, C.
R.: Hyporheic zone denitrification: Controls on effective reaction depth and
contribution to whole-stream mass balance, Water Resour. Res., 49,
6298–6316, 2013.
Hauxwell, J., Cebrian, J., and Valiela, I.: Eelgrass Zostera marina loss in
temperate estuaries: Relationship to land-derived nitrogen loads and effect
of light limitation imposed by algae, Mar. Ecol. Prog. Ser., 247, 59–73, 2003.
Hedin, L. O., von Fischer, J. C., Ostrom, N. E., Kennedy, B. P., Brown, M. G., and Robertson, G. P.: Thermodynamic constraints on nitrogentransformations and other biogeochemicalprocesses at soil–stream interfaces, Ecology, 79, 684–703, 1998.
Heisler, J. P., Glibert, P., Burkholder, J., Anderson, D., Cochlan, W.,
Dennison, W., Dortch, Q., Gobler, C., Heil, C., Humphries, E., Lewitus, A.,
Magnien, R., Marshall, H., Sellner, K., Stockwell, D. A., Stoecker, D., and
Suddleson, M.: Eutrophication and Harmful Algal Blooms: A Scientific
Consensus, Harmful Algae, 8, 3–13, 2008.
Hendry, M. J., McCready, R. G. L., and Gould, W. D.: Distribution, source and
evolution of nitrate in a glacial till of southern Alberta, Canada, J.
Hydrol., 70, 177–198, https://doi.org/10.1016/0022-1694(84)90121-5, 1984.
Hinkle, S. R., Böhlke, J. K., and Fisher, L. H.: Mass balance and isotope
effects during nitrogen transport through septic tank systems with
packed-bed (sand) filters, Sci. Total Environ., 407, 324–332,
https://doi.org/10.1016/j.scitotenv.2008.08.036, 2008.
Hollocher, T. C.: Source of the oxygen atoms of nitrate in the oxidation of
nitrite by Nitrobacter agilis and evidence against a P-O-N anhydride
mechanism in oxidative phosphorylation, Arch. Biochem. Biophys., 233,
721–727, https://doi.org/10.1016/0003-9861(84)90499-5, 1984.
Holloway, J., Dahlgren, R., Hansen, B., and Casey, W.: Contribution of
bedrock nitrogen to high nitrate concentrations in stream water, Nature,
395, 785–788, 1998.
Houlton, B. Z. and Bai, E.: Imprint of denitrifying bacteria on the global
terrestrial biosphere, P. Natl. Acad. Sci. USA, 106, 21713, https://doi.org/10.1073/pnas.0912111106, 2009.
Houlton, B. Z., Sigman, D. M., and Hedin, L. O.: Isotopic evidence for large
gaseous nitrogen losses from tropical rainforests, P. Natl. Acad. Sci.
USA, 103, 8745–8750, https://doi.org/10.1073/pnas.0510185103,
2006.
Howarth, R. W., Jensen, H. S., Marina, R., and Postma, H.: Transport to and
processing of P in near-shore and oceanic waters, in: Phosphorus in the
global environment, John Wiley & Sons Ltd, Chichester, UK, 323–346, 1995.
Howarth, R. W., Billen, G., Swaney, D., Townsend, A., Jaworski, N., Lajtha,
K., Downing, J. A., Elmgren, R., Caraco, N., Jordan, T., Berendse, F.,
Freney, J., Kudeyarov, V., Murdoch, P., and Zhao-Liang, Z.: Regional nitrogen
budgets and riverine N and P fluxes for the drainages to the North Atlantic
Ocean: Natural and human influences, Biogeochemistry, 35, 75–139, 1996.
Johannsen, A., Dähnke, K., and Emeis, K.: Isotopic composition of nitrate
in five German rivers discharging into the North Sea, Org. Geochem., 39,
1678–1689, 2008.
Kaiser, J., Hastings, M. G., Houlton, B. Z., Röckmann, T., and Sigman, D.
M.: Triple Oxygen Isotope Analysis of Nitrate Using the Denitrifier Method
and Thermal Decomposition of N2O, Anal. Chem., 79, 599–607, 2007.
Kasper, J. W., Denver, J. M., and York, J. K.: Suburban Groundwater Quality
as Influenced by Turfgrass and Septic Sources, Delmarva Peninsula, USA, J.
Environ. Qual., 44, 642–654, 2015.
Katz, B., Hornsby, H., Bohlke, J., and Mokray, M.: Sources and Chronology of
Nitrate Contamination in Spring Waters, Suwannee River Basin, Florida,
Water-Resources Investigations Report 99-4252, US Geological Survey,
Tallahassee, USA, 59 pp.,
https://doi.org/10.3133/wri994252, 1999.
Keeling, C. D.: The concentration and isotopic abundances of atmospheric
carbon dioxide in rural areas, Geochim. Cosmochim. Ac., 13, 322–334,
https://doi.org/10.1016/0016-7037(58)90033-4, 1958.
Keeling, C. D.: The concentration and isotopic abundances of carbon dioxide
in rural and marine air, Geochim. Cosmochim. Ac., 24, 277–298,
https://doi.org/10.1016/0016-7037(61)90023-0, 1961.
Kellman, L. and Hillaire-Marcel, C.: Nitrate cycling in streams: using
natural abundances of NO3–δ15N to measure in-situ denitrification,
Biogeochemistry, 43, 273–292, 1998.
Kendall, C.: Tracing Nitrogen Sources and Cycling in Catchments, chap. 16, in: Isotope Tracers in Catchment Hydrology, edited by:
Kendall, C. and McDonnel, J. J.,
Elsevier Science B.V.,
Amsterdam, the Netherlands,
519–576, 1998.
Kendall, C., Elliott, E., and Wankel, S.: Tracing Anthropogenic Inputs of
Nitrogen to Ecosystems, in: Stable isotopes in ecology and environmental
science, edited by: Michener, R. and Lajtha, K., Blackwell, Oxford, UK, 375–449,
2007.
Kennedy, C., Genereux, D., Corbett, D., and Mitasova, H.:
Relationships among groundwater age, denitrification, and the coupled
groundwater and nitrogen fluxes through a streambed, Water Resour.
Res., 45, W09402, https://doi.org/10.1029/2008WR007400, 2009.
Knapp, A. N., Sigman, D. M., and Lipschultz, F.: N isotopic composition of
dissolved organic nitrogen and nitrate at the Bermuda Atlantic Time-series
Study site, Global Biogeochem. Cy., 19, GB1018, https://doi.org/10.1029/2004GB002320, 2005.
Kreitler, C. W., Ragone, S. E., and Katz, B. G.: N15/N14 Ratios of
Ground-Water Nitrate, Long Island, New Yorka, Groundwater, 16, 404–409,
1978.
Kroopnick, P. and Craig, H.: Atmospheric oxygen: isotopic composition and
solubility fractionation, Science, 175, 54–55,
https://doi.org/10.1126/science.175.4017.54, 1972.
Krumholz, J. S.: Spatial and temporal patterns in nutrient standing stock
and mass-balance in response to load reduction in a temperate estuary,
PhD thesis, University of Rhode Island, Kingston, RI, USA, 401 pp., 2012.
Latimer, J. and Charpentier, M.: Nitrogen inputs to seventy-four southern
New England estuaries: Application of a watershed nitrogen loading model,
Estuar. Coast. Shelf Sci., 89, 125–136, 2010.
Lehmann, M. F., Sigman, D. M., McCorkle, D. C., Brunelle, B. G., Hoffmann,
S., Kienast, M., Cane, G., and Clement, J.: Origin of the deep Bering Sea
nitrate deficit: Constraints from the nitrogen and oxygen isotopic
composition of water column nitrate and benthic nitrate fluxes, Global
Biogeochem. Cy., 19, GB4005, https://doi.org/10.1029/2005GB002508, 2005.
Lin, J., Böhlke, J. K., Huang, S., Gonzalez-Meler, M., and Sturchio, N.
C.: Seasonality of nitrate sources and isotopic composition in the Upper
Illinois River, J. Hydrology, 568, 849–861, 2019.
Mayer, B., Boyer, E. W., Goodale, C., Jaworski, N. A., van Breemen, N.,
Howarth, R. W., Seitzinger, S., Billen, G., Lajtha, K., Nadelhoffer, K., Van
Dam, D., Hetling, L. J., Nosal, M., and Paustian, K.: Sources of nitrate in
rivers draining sixteen watersheds in the northeastern US: Isotopic
constraints, Biogeochemistry, 57, 171–197, 2002.
McClelland, J. W., Valiela, I., and Michener, R. H.: Nitrogen-stable isotope
signatures in estuarine food webs: A record of increasing urbanization in
coastal watersheds, Limnol. Oceanogr., 42, 930–937, 1997.
McMahon, P. B. and Böhlke, J. K.: Regional patterns in the isotopic
composition of natural and anthropogenic nitrate in groundwater, High
Plains, USA, Environ. Sci. Technol., 40, 2965–2970,
https://doi.org/10.1021/es052229q, 2006.
Mengis, M., Walther, U., Bernasconi, S. M., and Wehrli, B.: Limitations of
Using δ18O for the Source Identification of Nitrate in Agricultural
Soils, Environ. Sci. Technol., 35, 1840–1844, 2001.
Michener, R. and Lajtha, K.: Stable Isotopes in Ecology and Environmental Science, Second Edition, Blackwell Publishing LTd, 2007.
Moran, S. B., Stachelhaus, S. L., Kelly, R. P., and Brush, M. J.: Submarine
Groundwater Discharge as a Source of Dissolved Inorganic Nitrogen and
Phosphorus to Coastal Ponds of Southern Rhode Island, Estuar. Coast.,
37, 104–118, 2014.
Morford, S. L., Houlton, B. Z., and Dahlgren, R. A.: Geochemical and tectonic
uplift controls on rock nitrogen inputs across terrestrial ecosystems,
Global Biogeochem. Cy., 30, 333–349, 2016.
Mueller, D. K., Hamilton, P. A., Helsel, D. R., Hitt, K. J., and Ruddy, B. C.: Nutrients in ground water and surface water of the United
States: An analysis of data through 1992, US Department of the Interior, US
Geological Survey, Denver, Colorado, USA, 81 pp., https://doi.org/10.3133/wri954031, 1995.
Mulholland, M. R. and Lomas, M. W.: Chap. 7, Nitrogen Uptake and Assimilation, in: Nitrogen in the Marine Environment, 2nd Edn., edited by: Capone, D. G., Bronk, D. A., Mulholland, M. R., and Carpenter, E. J., Academic Press, San Diego, 303–384, 2008.
Mulholland, P. J. and Hill, W. R.: Seasonal patterns in streamwater nutrient
and dissolved organic carbon concentrations: Separating catchment flow path
and in-stream effects, Water Resour. Res., 33, 1297–1306, 1997.
Mulholland, P. J., Wilson, G. V., and Jardine, P. M.: Hydrogeochemical
Response of a Forested Watershed to Storms: Effects of Preferential Flow
Along Shallow and Deep Pathways, Water Resour. Res., 26, 3021–3036, 1990.
Murphy, J. and Riley, J. P.: A modified single solution method for the determinatino of
phosphate in natural waters, Anal. Chim. Acta, 27, 31, https://doi.org/10.1016/S0003-2670(00)88444-5, 1962.
Narragansett Bay Estuary Program: State of Narragansett Bay and Its
Watershed, Narragansett Bay Estuary Program, Technical Report for Narragansett Bay Estuary Program
Providence, RI, USA,
166 pp., 2017.
National Atmospheric Deposition Program, NTN Data Retrieval, available at:
http://nadp.slh.wisc.edu/data/NTN/ (last access: November 2019), 2019.
National Water Quality Monitoring Council: Water Quality Portal, available at: https://www.waterqualitydata.us/ (last access: November 2019), 2020.
Needoba, J., Waser, D., Harrison, P., and Calvert, S.: Nitrogen Isotope
Fractionation in 12 Species of Marine Phytoplankton During Growth on
Nitrate, Mar. Ecol. Progr. Ser., 255, 81–91,
2003.
Nixon, S. W., Granger, S. L., and Nowicki, B. L.: An assessment of the annual mass balance of carbon, nitrogen, and phosphorus in Narragansett Bay, Biogeochemistry, 31, 15–61, 1995.
Nixon, S. W., Buckley, B. A., Granger, S. L., Harris, L. A., Oczkowski, A.
J., Fulweiler, R. W., and Cole, L. W.: Nitrogen and Phosphorus Inputs to
Narragansett Bay: Past, Present, and Future, in: Science for
Ecosystem-based Management, edited by:
Desbonnet, A. and Costa-Pierce, B. A., Springer, New York, USA,
2008.
NOAA National Centers for Environmental information: Climate at a Glance:
County Time Series, available at: https://www.ncdc.noaa.gov/cag/ (last access: 15 November 2019), 2019.
Pabich, W., Valiela, I., and Hemond, H.: Relationship between DOC
concentration and vadose zone thickness and depth below water table in
groundwater of Cape Cod, USA, Biogeochemistry, 55, 247–268, 2001.
Quilbé, R., Rousseau, A., Duchemin, M., Poulin, A., Gangbazo, G., and
Villeneuve, J.: Selecting a Calculation Method to Estimate Sediment and
Nutrient Loads in Streams: Application to the Beaurivage River (Québec,
Canada), J. Hydrology, 326, 295, https://doi.org/10.1016/j.jhydrol.2005.11.008, 2006.
Rollinson, V. R., Granger, J., Clark, S. C., Blanusa, M. L., Koerting, C. P., Vaudrey, J. M. P., Treibergs, L. A., Westbrook, H. C., Matassa, C. M., Hastings, M. K., Tobias, C. R.: Seasonal nitrogen concentrations and nitrate isotopes of a New England River from 2018 to 2019, PANGAEA [Dataset], https://doi.org/10.1594/PANGAEA.931561, 2021.
Savarino, J. and Thiemens, M.: Analytical procedure to determine both
δ18O and δ17O of H2O2 in natural water and first
measurements, Atmos. Environ., 33, 3683–3690, 1999.
Sebestyen, S. D., Ross, D. S., Shanley, J. B., Elliott, E. M., Kendall, C.,
Campbell, J. L., Dail, D. B., Fernandez, I. J., Goodale, C. L., Lawrence, G.
B., Lovett, G. M., McHale, P. J., Mitchell, M. J., Nelson, S. J., Shattuck,
M. D., Wickman, T. R., Barnes, R. T., Bostic, J. T., Buda, A. R., Burns, D.
A., Eshleman, K. N., Finlay, J. C., Nelson, D. M., Ohte, N., Pardo, L. H.,
Rose, L. A., Sabo, R. D., Schiff, S. L., Spoelstra, J., and Williard, K. W.
J.: Unprocessed Atmospheric Nitrate in Waters of the Northern Forest Region
in the US and Canada, Environ. Sci. Technol., 53, 3620–3633, 2019.
Sebilo, M., Billen, G., Grably, M., and Mariotti, A.: Isotopic composition of
nitrate-nitrogen as a marker of riparian and benthic denitrification at the
scale of the whole Seine River system, Biogeochemistry, 63, 35–51, 2003.
Sebilo, M., Billen, G., Mayer, B., Billiou, D., Grably, M., Garnier, J., and
Mariotti, A.: Assessing Nitrification and Denitrification in the Seine River
and Estuary Using Chemical and Isotopic Techniques, Ecosystems, 9, 564–577,
2006.
Seitzinger, S. and Sanders, R.: Contribution of Dissolved Organic Nitrogen
From Rivers to Estuarine Eutrophication, Mar. Ecol. Progr. Ser., 159, 1–12, 1997.
Sigman, D. and Fripiat, F.: Nitrogen isotopes in the ocean, in:
Encyclopedia of Ocean Sciences, edited by: Kirk, J., Cochran Henry Bokuniewicz Patricia Yager
Cambridge, MA, USA, Elsevier, 263–278, https://doi.org/10.1016/B978-0-12-409548-9.11605-7, 2019.
Sigman, D., Casciotti, K., Andreani, M., Barford, C., Hastings, M., and
Bohlke, J.: A Bacterial Method for the Nitrogen Isotopic Analysis of Nitrate
in Seawater and Freshwater, Anal. Chem., 73, 4145–4153, 2001.
Sigman, D., Karsh, K., and Casciotti, K. L.: Nitrogen Isotopes in the Ocean,
in: Encyclopedia of ocean sciences, edited by: Steele, J. H., Encyclopedia of Ocean Sciences, 2nd Edn.,
Amsterdam, the Netherlands, Academic Press, 40–54, 2009.
Snider, D. M., Spoelstra, J., Schiff, S. L., and Venkiteswaran, J. J.: Stable
Oxygen Isotope Ratios of Nitrate Produced from Nitrification: 18O-Labeled
Water Incubations of Agricultural and Temperate Forest Soils, Environ. Sci.
Technol., 44, 5358–5364, 2010.
Solórzano, L. and Sharp, J. H.: Determination of total dissolved
phosphorus and particulate phosphorus in natural waters, Limnol. Oceanogr.,
25, 754–758, 1980.
Stevenson, F. J.: Humus Chemistry: Genesis, Composition, Reactions, 2nd edition,
John Wiley and Sons, New York, USA, 1994.
Strickland, J. D. and Parsons, T. R.: A Practical Handbook of Seawater
Analysis, 2nd edition, Fisheries Research Board of Canada, Ottawa, Canada,
1972.
Thiemens, M. H.: Mass-Independent Isotope Effects in Planetary Atmospheres
and the Early Solar System, Science, 283, 341–345,
https://doi.org/10.1126/science.283.5400.341, 1999.
Tiner, R., Berquist, H., Halavik, T., and MacLachlan, A.: Eelgrass Survey for
Eastern Long Island Sound, Connecticut and New York, US Fish and Wildlife
Service, National Wetlands Inventory Program, Hadley, USA, 22 pp., 2003.
Townsend, M., Young, D., and Macko, S.: Kansas case study applications of
nitrogen-15 natural abundance method for identification of nitrate sources,
Journal of Hazardous Substance Research, 4, 22 pp., 2003.
US Census Bureau: 2017 TIGER/Line Shapefiles (Area_Water), 2019 TIGER/Line Shapefiles (machinereadable data files)/prepared by the U.S. Census Bureau, 2019,
2017.
US Environmental Protection Agency: Method 365.3: Phosphorous, All Forms
(Colorimetric, Ascorbic Acid, Two Reagent), Environmental Monitoring
Systems Laboratory Office of Research and Development, Environmental Monitoring Systems Laboratory Office Of Research and Development U.S. Environmental Protection Agency Cincinnati, Ohio 45268, 18 pp., 1978.
US Environmental Protection Agency: Method 350.1: Determination of Ammonia
Nitrogen by semi-automated Colorimetry, Environmental Monitoring Systems
Laboratory Office of Research and Development, Environmental Monitoring Systems Laboratory Office Of Research and Development U.S. Environmental Protection Agency Cincinnati, Ohio 45268, 15 pp., 1993a.
US Environmental Protection Agency: Method 353.2: Revision 2.0:
Determination of Nitrate-Nitrite Nitrogen by Automated Colorimetry,
Environmental Monitoring Systems Laboratory Office of Research and
Development, Environmental Monitoring Systems Laboratory Office Of Research and Development U.S. Environmental Protection Agency Cincinnati, Ohio 45268, 15 pp., 1993b.
US Environmental Protection Agency: Fact Sheet Spring 2005: South County
RI Watersheds, SDMS Doc ID 579486, Flyer created by: United States Enivronmental Protection Agency New England, 2005.
US Environmental Protection Agency: Authorization to Discharge under the
Rhode Island Pollutant Discharge Elimination System, Permit No. RI0000191, Kenyon Industries, Richmond, USA, 2010.
US Geological Survey: National Atlas of the United States for Streams and
Waterbodies of the United States, available at: http://nationalatlas.gov (last acces: September 2020),
2005.
US Geological Survey: 20140331, NLCD 2011 Land Cover, U.S. Geological Survey, Sioux Falls, SD, U.S. Geological Survey,
2011.
URIEDC_RIGIS: Watershed Boundary Dataset HUC 12, Credit:
USDA-NRCS, USEPA, RI-DEM, 2019.
Valiela, I., McClelland, J., Hauxwell, J., Behr, P. J., Hersh, D., and
Foreman, K.: Macroalgal blooms in shallow estuaries: controls and
ecophysiological and ecosystem consequences, Limnol. Oceanogr., 42,
1105–1118, 1997.
Vaudrey, J., Yarish, C., Kim, J., Pickerell, C., Brousseau, L., Eddings, J.,
and Sautkulis, M.: Long Island Sound Nitrogen Loading Model, 2016.
Vaudrey, J., Brousseau, L., Yarish, C., and Kyun Kim, J.: Modeling nitrogen
loads to address point and non-point source nutrient pollution, in: 24th
Biennial CEFT Conference, Rhode Island, USA, November 5–9, 2017,
Providence, RI, 41 pp., 2017.
Veale, N., Visser, A., Esser, B., Singleton, M., and Moran, J.: Nitrogen
Cycle Dynamics Revealed Through δ18O–NO3-Analysis in California
Groundwater, Geosciences, 9, 95, https://doi.org/10.3390/geosciences9020095, 2019.
Wood-Pawcatuck Watershed Association: Wood-Pawcatuck Watershed Baseline
Assessment, Wood-Pawcatuck Watershed Flood Resiliency Management Plan, Fuss
and O'Neill, Manchester, USA, 2016.
Wood-Pawcatuck Watershed Association: Wood-Pawcatuck Water Quality
Monitoring Data: available at: https://wpwa.org/water-quality/ (last access: November 2019), 2020.
Xue, D., Botte, J., De Baets, B., Accoe, F., Nestler, A., Taylor, P., Van
Cleemput, O., Berglund, M., and Boeckx, P.: Present limitations and future
prospects of stable isotope methods for nitrate source identification in
surface- and groundwater, Water Res., 43, 1159–1170,
https://doi.org/10.1016/j.watres.2008.12.048, 2009.
Zhang, L., Altabet, M. A., Wu, T., and Hadas, O.: Sensitive measurement of
NH4 +15N/14N (δ15NH4 + ) at natural abundance levels in fresh and
saltwaters, Anal. Chem., 79, 5297–5303, 2007.
Short summary
We measured nutrients and the naturally occurring nitrogen (N) and oxygen (O) stable isotope ratios of nitrate discharged from a New England river over an annual cycle, to monitor N loading and identify dominant sources from the watershed. We uncovered a seasonality to loading and sources of N from the watershed. Seasonality in the nitrate isotope ratios also informed on N cycling, conforming to theoretical expectations of riverine nutrient cycling.
We measured nutrients and the naturally occurring nitrogen (N) and oxygen (O) stable isotope...
Altmetrics
Final-revised paper
Preprint