Articles | Volume 14, issue 12
https://doi.org/10.5194/bg-14-3111-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/bg-14-3111-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
26 Jun 2017
Research article |
| 26 Jun 2017
Quantifying nutrient uptake as driver of rock weathering in forest ecosystems by magnesium stable isotopes
David Uhlig
CORRESPONDING AUTHOR
GFZ German Research Centre for Geosciences, Earth Surface Geochemistry, Telegrafenberg, 14473 Potsdam, Germany
Jan A. Schuessler
GFZ German Research Centre for Geosciences, Earth Surface Geochemistry, Telegrafenberg, 14473 Potsdam, Germany
Julien Bouchez
GFZ German Research Centre for Geosciences, Earth Surface Geochemistry, Telegrafenberg, 14473 Potsdam, Germany
present address: IPGP-CNRS Institut de Physique du Globe de Paris, Rue Jussieu, 75238 Paris CEDEX 05, France
Jean L. Dixon
GFZ German Research Centre for Geosciences, Earth Surface Geochemistry, Telegrafenberg, 14473 Potsdam, Germany
present address: Department of Earth Sciences, Montana State University, Bozeman, Montana 59717, USA
Friedhelm von Blanckenburg
GFZ German Research Centre for Geosciences, Earth Surface Geochemistry, Telegrafenberg, 14473 Potsdam, Germany
Institute of Geological Sciences, Freie Universität Berlin, Malteserstr. 74–100, 12249 Berlin, Germany
Related authors
No articles found.
Sofía López-Urzúa, Louis Derry, and Julien Bouchez
EGUsphere, https://doi.org/10.5194/egusphere-2025-78, https://doi.org/10.5194/egusphere-2025-78, 2025
This preprint is open for discussion and under review for Biogeosciences (BG).
Short summary
Short summary
Silicon (Si) is essential for ecosystem health and Earth's climate, yet human activities such as agriculture have significantly disrupted its natural cycle. In a French agricultural catchment, we found that crop harvesting removes most of the Si released from rocks—1 to 4 times more than the dissolved Si transport downstream by rivers. Using geochemical tools, including Si isotopes and germanium-silicon ratio, we traced Si cycling and highlighted the impact of agriculture on Si exports.
Rahmantara Trichandi, Klaus Bauer, Trond Ryberg, Benjamin Heit, Jaime Araya Vargas, Friedhelm von Blanckenburg, and Charlotte M. Krawczyk
Earth Surf. Dynam., 12, 747–763, https://doi.org/10.5194/esurf-12-747-2024, https://doi.org/10.5194/esurf-12-747-2024, 2024
Short summary
Short summary
This study investigates subsurface weathering zones, revealing their structure through shear wave velocity variations. The research focuses on the arid climate of Pan de Azúcar National Park, Chile, using seismic ambient noise recordings to construct pseudo-3D models. The resulting models show the subsurface structure, including granite gradients and mafic dike intrusions. Comparison with other sites emphasizes the intricate relationship between climate, geology, and weathering depth.
Yutian Ke, Damien Calmels, Julien Bouchez, Marc Massault, Benjamin Chetelat, Aurélie Noret, Hongming Cai, Jiubin Chen, Jérôme Gaillardet, and Cécile Quantin
Earth Surf. Dynam., 12, 347–365, https://doi.org/10.5194/esurf-12-347-2024, https://doi.org/10.5194/esurf-12-347-2024, 2024
Short summary
Short summary
Through a river cross-section, we show that fluvial organic carbon in the lower Huanghe has clear vertical and lateral heterogeneity in elemental and isotopic signals. Bank erosion supplies terrestrial organic carbon to the fluvial transport. Physical erosion of aged and refractory organic carbon, including radiocarbon-dead organic carbon source from the biosphere, from relatively deep soil horizons of the Chinese Loess Plateau contributes to fluvial particulate organic carbon in the Huanghe.
Ferdinand J. Hampl, Ferry Schiperski, Christopher Schwerdhelm, Nicole Stroncik, Casey Bryce, Friedhelm von
Blanckenburg, and Thomas Neumann
Earth Surf. Dynam., 11, 511–528, https://doi.org/10.5194/esurf-11-511-2023, https://doi.org/10.5194/esurf-11-511-2023, 2023
Short summary
Short summary
We investigated the mineral content and geochemical composition of the upper 6 m of regolith, formed by weathering of granitic rocks in Mediterranean and humid climate zones. We found that the development of the upper regolith in the Mediterranean climate is controlled by secondary minerals which cause fracturing and thus facilitate fluid infiltration to depth. The upper regolith in the humid climate is controlled by secondary minerals that cause a reduction of fluid infiltration to depth.
Yutian Ke, Damien Calmels, Julien Bouchez, and Cécile Quantin
Earth Syst. Sci. Data, 14, 4743–4755, https://doi.org/10.5194/essd-14-4743-2022, https://doi.org/10.5194/essd-14-4743-2022, 2022
Short summary
Short summary
In this paper, we introduce the largest and most comprehensive database for riverine particulate organic carbon carried by suspended particulate matter in Earth's fluvial systems: 3546 data entries for suspended particulate matter with detailed geochemical parameters are included, and special attention goes to the elemental and isotopic carbon compositions to better understand riverine particulate organic carbon and its role in the carbon cycle from regional to global scales.
Pierre Nevers, Julien Bouchez, Jérôme Gaillardet, Christophe Thomazo, Delphine Charpentier, Laëticia Faure, and Catherine Bertrand
Earth Surf. Dynam., 9, 487–504, https://doi.org/10.5194/esurf-9-487-2021, https://doi.org/10.5194/esurf-9-487-2021, 2021
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.
Travis Clow, Jane K. Willenbring, Mirjam Schaller, Joel D. Blum, Marcus Christl, Peter W. Kubik, and Friedhelm von Blanckenburg
Geochronology, 2, 411–423, https://doi.org/10.5194/gchron-2-411-2020, https://doi.org/10.5194/gchron-2-411-2020, 2020
Short summary
Short summary
Meteoric beryllium-10 concentrations in soil profiles have great capacity to quantify Earth surface processes, such as erosion rates and landform ages. However, determining these requires an accurate estimate of the delivery rate of this isotope to local sites. Here, we present a new method to constrain the long-term delivery rate to an eroding western US site, compare it against existing delivery rate estimates (revealing considerable disagreement between methods), and suggest best practices.
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.
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.
Aurèle Vuillemin, André Friese, Richard Wirth, Jan A. Schuessler, Anja M. Schleicher, Helga Kemnitz, Andreas Lücke, Kohen W. Bauer, Sulung Nomosatryo, Friedhelm von Blanckenburg, Rachel Simister, Luis G. Ordoñez, Daniel Ariztegui, Cynthia Henny, James M. Russell, Satria Bijaksana, Hendrik Vogel, Sean A. Crowe, Jens Kallmeyer, and the Towuti Drilling Project
Science team
Biogeosciences, 17, 1955–1973, https://doi.org/10.5194/bg-17-1955-2020, https://doi.org/10.5194/bg-17-1955-2020, 2020
Short summary
Short summary
Ferruginous lakes experience restricted primary production due to phosphorus trapping by ferric iron oxides under oxic conditions. We report the presence of large crystals of vivianite, a ferrous iron phosphate, in sediments from Lake Towuti, Indonesia. We address processes of P retention linked to diagenesis of iron phases. Vivianite crystals had light Fe2+ isotope signatures and contained mineral inclusions consistent with antecedent processes of microbial sulfate and iron reduction.
Renee van Dongen, Dirk Scherler, Hella Wittmann, and Friedhelm von Blanckenburg
Earth Surf. Dynam., 7, 393–410, https://doi.org/10.5194/esurf-7-393-2019, https://doi.org/10.5194/esurf-7-393-2019, 2019
Short summary
Short summary
The concentration of cosmogenic 10Be is typically measured in the sand fraction of river sediment to estimate catchment-average erosion rates. Using the sand fraction in catchments where the 10Be concentrations differ per grain size could potentially result in biased erosion rates. In this study we investigated the occurrence and causes of grain size-dependent 10Be concentrations and identified the types of catchments which are sensitive to biased catchment-average erosion rates.
Paul Floury, Jérôme Gaillardet, Eric Gayer, Julien Bouchez, Gaëlle Tallec, Patrick Ansart, Frédéric Koch, Caroline Gorge, Arnaud Blanchouin, and Jean-Louis Roubaty
Hydrol. Earth Syst. Sci., 21, 6153–6165, https://doi.org/10.5194/hess-21-6153-2017, https://doi.org/10.5194/hess-21-6153-2017, 2017
Short summary
Short summary
We present a new prototype
lab in the fieldnamed River Lab (RL) designed for water quality monitoring to perform a complete analysis at sub-hourly frequency of major dissolved species in river water. The article is an analytical paper to present the proof of concept, its performances and improvements. Our tests reveal a significant improvement of reproducibility compared to conventional analysis in the laboratory. First results are promising for understanding the critical zone.
Jean L. Dixon, Friedhelm von Blanckenburg, Kurt Stüwe, and Marcus Christl
Earth Surf. Dynam., 4, 895–909, https://doi.org/10.5194/esurf-4-895-2016, https://doi.org/10.5194/esurf-4-895-2016, 2016
Short summary
Short summary
We quantify the glacial legacy of Holocene erosion at the eastern edge of the European Alps and add insight to the debate on drivers of Alpine erosion. We present the first data explicitly comparing 10Be-based erosion rates in previously glaciated and non-glaciated basins (n = 26). Erosion rates vary 5-fold across the region, correlating with local topography and glacial history. Our approach and unique study site allow us to isolate the role of glacial topographic legacies from other controls.
S. Emmanuel, J. A. Schuessler, J. Vinther, A. Matthews, and F. von Blanckenburg
Biogeosciences, 11, 5493–5502, https://doi.org/10.5194/bg-11-5493-2014, https://doi.org/10.5194/bg-11-5493-2014, 2014
Related subject area
Biogeochemistry: Stable Isotopes & Other Tracers
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
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)
Stable iron isotope signals indicate a “pseudo-abiotic" process driving deep iron release in methanic sediments
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
Seasonality of nitrogen sources, cycling, and loading in a New England river discerned from nitrate isotope ratios
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
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.
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.
Susann Henkel, Bo Liu, Michael Staubwasser, Simone A. Kasemann, Anette Meixner, David Aromokeye, Michael W. Friedrich, and Sabine Kasten
EGUsphere, https://doi.org/10.5194/egusphere-2024-1942, https://doi.org/10.5194/egusphere-2024-1942, 2024
Short summary
Short summary
We intend to unravel iron (Fe) reduction pathways in high depositional methanic sediments because pools of Fe minerals could stimulate methane oxidation, but also generation. Our data from the North Sea indicate that Fe release takes place mechanistically different to Fe reduction in shallow sediments that 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.
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.
Veronica R. Rollinson, Julie Granger, Sydney C. Clark, Mackenzie L. Blanusa, Claudia P. Koerting, Jamie M. P. Vaudrey, Lija A. Treibergs, Holly C. Westbrook, Catherine M. Matassa, Meredith G. Hastings, and Craig R. Tobias
Biogeosciences, 18, 3421–3444, https://doi.org/10.5194/bg-18-3421-2021, https://doi.org/10.5194/bg-18-3421-2021, 2021
Short summary
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.
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
Aciego, S. M., Riebe, C. S., Hart, S. C., Blakowski, M. A., Carey, C. J., Aarons, S. M., Dove, N. C., Botthoff, J. K., Sims, K. W. W., and Aronson, E. L: Dust outpaces bedrock in nutrient supply to montane forest ecosystems, Nat. Commun., 8, 14800, https://doi.org/10.1038/ncomms14800, 2017.
Anderson, S. P., Dietrich, W. E., and Brimhall, G. H.: Weathering profiles, mass-balance analysis, and rates of solute loss: Linkages between weathering and erosion in a small, steep catchment, Geol. Soc. Am. Bull., 114, 1143–1158, 2002.
Andrews, M. G., Jacobson, A. D., Lehn, G. O., Horton, T. W., and Craw, D.: Radiogenic and stable Sr isotope ratios (87Sr/86Sr, δ88/86Sr) as tracers of riverine cation sources and biogeochemical cycling in the Milford Sound region of Fiordland, New Zealand, Geochim. Cosmochim. Ac., 173, 284–303, 2016.
Arunachalam, J., Emons, H., Krasnodebska, H., and Mohl, C.: Sequential extraction studies on homogenized forest soil samples, Sci. Total Environ., 181, 147–159, 1996.
Bales, R. C., Hopmans, J. W., O'Geen, A. T., Meadows, M., Hartsough, P. C., Kirchner, P., Hunsaker, C. T., and Beaudette, D.: Soil moisture response to snowmelt and rainfall in a Sierra Nevada Mixed-Conifer forest, Vadose Zone J., 10, 786–799, 2011.
Bartoli, F.: The biogeochemical cycle of silicon in two temperate forest ecosystems, Ecol. Bull., 35, 469–476, 1983.
Bateman, P .C. and Wones, D. R.: Huntington Lake Quadrangle, Central Sierra Nevada, California – Analytical Data, Shorter Contributions to General Geology, Geological Survey Professional Paper 724-A, USGS Numbered Series, available at: https://pubs.er.usgs.gov/publication/pp724A (last access: 22 June 2017), 1972.
Brimhall, G. H. and Dietrich, W. E.: Constitutive mass balance relations between chemical composition, volume, density, porosity, and strain in metasomatic hydrochemical systems: results on weathering and pedogenesis, Geochim. Cosmochim. Ac., 51, 567–587, 1987.
Black, J. R., Epstein, E., Rains, W. D., Yin, Q.-Z., and Casey, W. H.: Magnesium-isotope fractionation during plant growth, Environ. Sci. Technol., 42, 7831–7836, 2008.
Bolou-Bi, E. B., Vigier, N., Poszwa, A., Boudot, J. P., and Dambrine, E.: Effects of biogeochemical processes on magnesium isotope variations in a forested catchment in the Vosges Mountains (France), Geochim. Cosmochim. Ac., 87, 341–355, 2012.
Bonan, G. B.: Forests and climate change: forcings, feedbacks, and the climate benefits of forests, Science, 320, 1444–1449, 2008.
Bouchez, J., von Blanckenburg, F., and Schuessler, J. A.: Modelling novel stable isotopes in the weathering zone, Am. J. Sci., 313, 267–308, 2013.
Boy, J. and Wilcke, W.: Tropical Andean forest derives calcium and magnesium from Saharan dust, Global Biogeochem. Cy., 22, GB1027, https://doi.org/10.1029/2007GB002960, 2008.
Brantley, S. L. and Lebedeva, M.: Learning to Read the Chemistry of Regolith to Understand the Critical Zone, Annu. Rev. Earth Pl. Sc., 39, 387–416, 2011.
Brantley, S. L., Megonigal, J. P., Scatena, F. N., Balogh-Brunstad, Z., Barnes, R. T., Bruns, M. A., Van Cappellen, P., Dontsova, K., Hartnett, H. E., Hartshorn, A. S., Heimsath, A., Herndon, E., Jin, L., Keller, C. K., Leake, J. R., McDowell, W. H., Meinzer, F. C., Mozdzer, T. J., Petsch, S., Pett-Ridge, J., Pregitzer, K. S., Raymond, P. A., Riebe, C. S., Shumaker, K., Sutton-Grier, A., Walter, R., and Yoo, K.: Twelve testable hypotheses on the geobiology of weathering, Geobiology, 9, 1–26, 2011.
Bullen, T. and Chadwick, O.: Ca, Sr and Ba stable isotopes reveal the fate of soil nutrients along a tropical climosequence in Hawaii, Chem. Geol., 422, 25–45, 2016.
Chapela Lara, M., Buss, H. L., Pogge von Strandmann, P. A. E., Moore, O. W., and Schuessler, J. A.: The influence of critical zone processes on the Mg isotope budget in a tropical, highly weathered andesitic catchment, Geochim. Cosmochim. Ac., 202, 77–100, 2017.
Clymans, W., Conley, D. J., Battles, J. J., Frings, P. J., Koppers, M. M., Likens, G. E., and Johnson, C. E.: Silica uptake and release in live and decaying biomass in a northern hardwood forest, Ecology, 97, 3044–3057, 2016.
Cornelis, J. T., Ranger, J., Iserentant, A., and Delvaux, B.: Tree species impact the terrestrial cycle of silicon through various uptake, Biogeochemistry, 97, 231–245, 2010.
Dahlgren, R. A., Boettinger, J. L., Huntington, G. L., and Amundson, R. G.: Soil development along an elevational transect in the western Sierra Nevada, California, Geoderma, 78, 207–236, 1997.
Dixon, J. L. and von Blanckenburg, F.: Soils as pacemakers and limiters of global silicate weathering, C. R. Geosci., 344, 597–609, 2012.
Dixon, J. L., Heimsath, A. M., and Amundson, R.: The critical role of climate and saprolite weathering in landscape evolution, Earth Surf. Proc. Land., 34, 1507–1521, 2009.
Eagan, S. M., Hunsaker, C. T., Dolanc, C. R., Lynch, M. E., and Johnson, C. R.: Discharge and Sediment Loads at the Kings River Experimental Forest in the Southern Sierra Nevada of California, in: Advancing the fundamental sciences: proceedings of the Forest Service National Earth Sciences Conference, edited by: Furniss, M., Clifton, C., and Ronnenberg, K., Gen. Tech. Rep. PNW-GTR-689, Forest Service, Pacific Northwest Research Station, 18–22 October 2004, Portland, OR, USA, 217–224, 2007.
Fraysse, F., Pokrovsky, O. S., Schott, J., and Meunier, J.-D.: Surface chemistry and reactivity of plant phytoliths in aqueous solutions, Chem. Geol., 258, 197–206, 2009.
Frings, P. J., Clymans, W., Fontorbe, G., De La Rocha, C. L., and Conley, D. J.: The continental Si cycle and its impact on the ocean Si isotope budget, Chem. Geol., 425, 12–36, 2016.
Galy, A., Yoffe, O., Janney, P. E., Williams, R. W., Cloquet, C., Alard, O., Halicz, L., Wadhwa, M., Hutcheon, I. D., Ramon, E., and Carignan, J.: Magnesium isotope heterogeneity of the isotopic standard SRM980 and new reference materials for magnesium-isotope-ratio measurements, J. Anal. Atom. Spectrom., 18, 1352–1356, 2003.
Galy, V., Peucker-Ehrenbrink, B., and Eglington, T.: Global carbon export from the terrestrial biosphere controlled by erosion, Nature, 521, 204–207, 2015.
George, E., Seith, B., Schaeffer, C., and Marschner, H.: Responses of Picea, Pinus and Pseudotsuga roots to heterogeneous nutrient distribution in soil, Tree Physiol., 17, 39–45, 1997.
Grady, K. C. and Hart, S. C.: Influences of thinning, prescribed burning, and wildfire on soil processes and properties in southwestern ponderosa pine forests: a retrospective study, Forest Ecol. Manag., 234, 123–135, 2006.
Graham, R. T. and Jain, T. B.: Ponderosa pine ecosystems, in: Proceedings of the Symposium on Ponderosa Pine: Issues, Trends, and Management, Gen. Tech. Rep. PSW-GTR-198, Pacific Southwest Research Station, Forest Service, US Department of Agriculture, 18–21 October 2004, Albany, CA, USA, 1–32, 2005.
Hahm, W. J., Riebe, C. S., Lukens, C. E., and Araki, S.: Bedrock composition regulates mountain ecosystems, P. Natl. Acad. Sci. USA, 111, 3338–3343, 2014.
Harder, H.: The role of magnesium in the formation of smectite mineral, Chem. Geol., 10, 31–39, 1972.
Hilton, R. G.: Climate regulates the erosional carbon export from the terrestrial biosphere, Geomorphology, 277, 118–132, 2017.
Jobbagy, E. G. and Jackson R. B.: The distribution of soil nutrients with depth: Global patterns and the imprint of plants, Biogeochemistry, 53, 51–77, 2001.
Johnson, C. M., Beard, B. L., and Albarède, F.: Geochemistry of Non-Traditional Stable Isotopes, Rev. Mineral. Geochem., 55, 1–454, 2004.
Johnson, C. E., Siccama, T. G., Denny, E. G., Koppers, M. M., and Vogt, D. J.: In situ decomposition of northern hardwood tree boles: decay rates and nutrient dynamics in wood and bark, Can. J. Forest Res., 44, 1515–1524, 2014.
Johnson, D. W., Hunsaker, C. T., Glass, D. W., Rau, B. M., and Roath, B. A.: Carbon and nutrient contents in soils from the Kings River Experimental Watersheds, Sierra Nevada Mountains, California, Geoderma, 160, 490–502, 2011.
Jongmans, A. G., van Breemen, N., Lundström, U., van Hees, P. A. W., Finlay, R. D., Srinivasan, M., Unestam, T., Giesler, R., Melkerud, P.-A., and Olsson, M.: Rock-eating fungi, Nature, 389, 682–683, 1997.
Kirchner, J. W., Finkel, R. C., Riebe, C. S., Granger, D. E., Clayton, J. L., King, J. G., and Megahan, W. F.: Mountain erosion over 10 yr, 10 k.y., and 10 m.y. time scales, Geology, 29, 591–594, 2001.
Klemmedson, J. O.: Decomposition and nutrient release from mixtures of Gambel oak and ponderosa pine leaf litter, Forest Ecol. Manag., 47, 349–361, 1992.
Klemmedson, J. O., Meier, C. E., and Campbell, R. E.: Litter fall transfers of dry matter and nutrients in ponderosa pine stands, Can. J. Forest Res., 20, 1105–1115, 1990.
Laclau, P.: Biomass and carbon sequestration of ponderosa pine plantations and native cypress forests in northwest Patagonia, Forest Ecol. Manag., 180, 317–333, 2003.
Landeweert, R., Hoffland, E., Finlay, R. D., Kuyper, T. W., and van Breemen, N.: Linking plants to rocks: ectomycorrhizal fungi mobilize nutrients from minerals, Trends Ecol. Evol., 16, 248–254, 2001.
Lang, F., Bauhus, J., Frossard, E., George, E., Kaiser, K., Kaupenjohann, M., Krüger, J., Matzner, E., Polle, A., Prietzel, J., Rennenberg, H., and Wellbrock, N.: Phosphorus in forest ecosystems: New insights from an ecosystem nutrition perspective, J. Plant Nutr. Soil Sc., 179, 129–135, 2016.
Law, B. E., Ryan, M. G., and Anthoni, P. M.: Seasonal and annual respiration of a ponderosa pine ecosystem, Glob. Change Biol., 5, 169–182, 1999.
Lucas, Y.: The role of plants in controlling rates and products of weathering: Importance of biological pumping, Annu. Rev. Earth Pl. Sc., 29, 135–163, 2001.
Ma, L., Teng, F. Z., Jin, L., Ke, S., Yang, W., Gu, H. O., and Brantley, S. L.: Magnesium isotope fractionation during shale weathering in the Shale Hills Critical Zone Observatory: Accumulation of light Mg isotopes in soils by clay mineral transformation, Chem. Geol., 397, 37–50, 2015.
Marschner, H: Marschner's mineral nutrition of higher plants, Academic press, available at: https://www.elsevier.com/books/marschners-mineral-nutrition-of-higher-plants/marschner/978-0-12-384905-2 (last access: 22 June 2017), 2011.
Mavromatis, V., Prokushkin, A. S., Pokrovsky, O. S., Viers, J., and Korets, M. A.: Magnesium isotopes in permafrost-dominated Central Siberian larch forest watersheds, Geochim. Cosmochim. Ac., 147, 76–89, 2014.
McCorkle, E. M., Berhe, A. A., Hunsaker, C. T., Johnson, D. W., McFarlane, K. J., Fogel, M. L., and Hart, S. C.: Tracing the source of soil organic matter eroded from temperate forest catchments using carbon and nitrogen isotopes, Chem. Geol., 44, 172–184, 2016.
Dai, M.-N., Bao, Z.-A., Chen, K.-Y., and Yuan, H.-L.: In situ Analysis of Mg Isotopic Compositions of Basalt Glasses by Femtosecond Laser Ablation Multi-collector Inductively Coupled Plasma Mass Spectrometry, Chinese J. Anal. Chem., 44, 173–178, 2016.
Moulton, K. L., West, J., and Berner, R. A.: Solute flux and mineral mass balance approaches to the quantification of plant effects on silicate weathering, Am. J. Sci., 300, 539–570, 2000.
Oeser, M., Wexer, S., Horn, I., and Schuth, S.: High-Precision Fe and Mg Isotope Ratios of Silicate Reference Glasses Determined In Situ by Femtosecond LA-MC-ICP-MS and by Solution Nebulisation MC-ICP-MS, Geostand. Geoanal. Res., 38, 311–328, 2014.
Opfergelt, S., Burton, K. W., Georg, R. B., West, A. J., Guicharnaud, R. A., Sigfusson, B., Siebert, C., Gislason, S. R., and Halliday, A. N.: Magnesium retention on the soil exchange complex controlling Mg isotope variations in soils, soil solutions and vegetation in volcanic soils, Iceland, Geochim. Cosmochim. Ac., 125, 110–130, 2014.
Pearson, J. A., Knight, D. H., and Fahey, T. J.: Biomass and nutrient accumulation during stand development in Wyoming lodgepole pine forests, Ecology, 68, 1966–1973, 1987.
Pogge von Strandmann, P. A. E., Elliott, T., Marschall, H. R., Coath, C., Lai, Y.-J., Jeffcoate, A. B., and Ionov, D. A.: Variations of Li and Mg isotope ratios in bulk chondrites and mantle xenoliths, Geochim. Cosmochim. Ac., 75, 5247–5268, 2011.
Porder, S., Vitousek, P. M., Chadwick, O. A., Chamberlain, C. P., and Hilley, G. E.: Uplift, Erosion and Phosphorus Limitation in Terrestrial Ecosystems, Ecosystems, 10, 158–170, 2007.
Riebe, C. S. and Granger, D. E.: Quantifying effects of deep and near-surface chemical erosion on cosmogenic nuclides in soils, saprolite, and sediment, Earth Surf. Proc. Land., 38, 523–533, 2013.
Röderstein, M., Hertel, D., and Leuschner, C.: Above-and below-ground litter production in three tropical montane forests in southern Ecuador, J. Trop. Ecol., 21, 483–492, 2005.
Roering, J. J., Marshall, J., Booth, A. M., Mort, M., and Jin, Q. S.: Evidence for biotic controls on topography and soil production, Earth Planet. Sc. Lett., 298, 183–190, 2010.
Ryu, J.-S., Vigier, N., Decarreau, A., Lee, S.-W., Le, K.-S., Song, H., and Petit, S.: Experimental investigation of Mg isotope fractionation during mineral dissolution and clay formation, Chem. Geol., 445, 135–145, 2016.
Schaller, M., von Blanckenburg, F., Hovius, N., and Kubik, P.: Large-scale erosion rates from in situ-produced cosmogenic nuclides in European river sediments, Earth Planet. Sc. Lett., 188, 441–458, 2001.
Schuessler, J. A. and von Blanckenburg, F.: Testing the limits of micro-scale analyses of Si stable isotopes by femtosecond laser ablation multicollector inductively coupled plasma mass spectrometry with application to rock weathering, Spectrochim. Acta B, 98, 1–18, 2014.
Schuessler, J. A., Kämpf, H., Koch, U., and Alawi, M.: Earthquake impact on iron isotope signatures recorded in mineral spring water, J. Geophys. Res.-Sol. Ea., 121, 8548–8568, https://doi.org/10.1002/2016JB013408, 2016.
Sommer, M., Jochheim, H., Höhn, A., Breuer, J., Zagorski, Z., Busse, J., Barkusky, D., Meier, K., Puppe, D., Wanner, M., and Kaczorek, D.: Si cycling in a forest biogeosystem – the importance of transient state biogenic Si pools, Biogeosciences, 10, 4991–5007, https://doi.org/10.5194/bg-10-4991-2013, 2013.
Stone, E. L. and Kalisz, P. J.: On the maximum extent of tree roots, Forest Ecol. Manag., 46, 59–102, 1991.
Tipper, E. T., Lemarchand, E., Hindshaw, R. S., Reynolds, B. C., and Bourdon, B.: Seasonal sensitivity of weathering processes: hints from magnesium isotopes in a glacial stream, Chem. Geol., 312–313, 80–92, 2012.
Uhlig, D., Schuessler, J. A., Bouchez, J., Dixon, J. L., and von Blanckenburg, F.: Supplementary dataset for: Quantifying nutrient uptake as driver of rock weathering in forest ecosystems by magnesium stable isotopes, GFZ Data Services, https://doi.org/10.5880/GFZ.3.3.2017.001, 2017.
Vitousek, P. M. and Farington, H.: Nutrient limitation and soil development: Experimental test of a biogeochemical theory, Biogeochemistry, 37, 63–75, 1997.
West, A. J., Galy, A., and Bickle, M. J.: Tectonic and climatic controls on silicate weathering, Earth Planet. Sc. Lett., 235, 211–228, 2005.
Wimpenny, J., Colla, C. A., Yin, Q.-Z., Rustad, J. R., and Casey, W. H.: Investigating the behavior of Mg isotopes during the formation of clay minerals, Geochim. Cosmochim. Ac., 128, 178–194, 2014.
Short summary
Plants and soil microbiota play an active role in rock weathering. Here we show that the coupling between erosion and weathering might be established by nutrients that are taken up by trees, are not recycled from plant litter and are missing in the dissolved river flux due to forest re-growth after clear cutting or due to erosion as coarse woody debris. To track this nutrient pathway we used magnesium stable isotopes in combination with innovative metrics over annual and millennial timescales.
Plants and soil microbiota play an active role in rock weathering. Here we show that the...
Altmetrics
Final-revised paper
Preprint