BG - recent papers
https://bg.copernicus.org/articles/
Combined list of the recent articles of the journal Biogeosciences and the recent discussion forum Biogeosciences DiscussionsIdeas and perspectives: Sensing energy and matter fluxes in a biota-dominated Patagonian landscape through environmental seismology – introducing the Pumalín Critical Zone Observatory
https://doi.org/10.5194/bg-21-1583-2024
<b>Ideas and perspectives: Sensing energy and matter fluxes in a biota-dominated Patagonian landscape through environmental seismology – introducing the Pumalín Critical Zone Observatory</b><br>
Christian H. Mohr, Michael Dietze, Violeta Tolorza, Erwin Gonzalez, Benjamin Sotomayor, Andres Iroume, Sten Gilfert, and Frieder Tautz<br>
Biogeosciences, 21, 1583–1599, https://doi.org/10.5194/bg-21-1583-2024, 2024<br>
Coastal temperate rainforests, among Earth’s carbon richest biomes, are systematically underrepresented in the global network of critical zone observatories (CZOs). Introducing here a first CZO in the heart of the Patagonian rainforest, Chile, we investigate carbon sink functioning, biota-driven landscape evolution, fluxes of matter and energy, and disturbance regimes. We invite the community to join us in cross-disciplinary collaboration to advance science in this particular environment.
2024-03-28T05:12:53+01:00Diurnal versus spatial variability of greenhouse gas emissions from an anthropogenically modified lowland river in Germany
https://doi.org/10.5194/bg-21-1613-2024
<b>Diurnal versus spatial variability of greenhouse gas emissions from an anthropogenically modified lowland river in Germany</b><br>
Matthias Koschorreck, Norbert Kamjunke, Uta Koedel, Michael Rode, Claudia Schuetze, and Ingeborg Bussmann<br>
Biogeosciences, 21, 1613–1628, https://doi.org/10.5194/bg-21-1613-2024, 2024<br>
We measured the emission of carbon dioxide (CO2) and methane (CH4) from different sites at the river Elbe in Germany over 3 days to find out what is more important for quantification: small-scale spatial variability or diurnal temporal variability. We found that CO2 emissions were very different between day and night, while CH4 emissions were more different between sites. Dried out river sediments contributed to CO2 emissions, while the side areas of the river were important CH4 sources.
2024-03-28T05:12:53+01:00Technical note: A comparison of methods for estimating coccolith mass
https://doi.org/10.5194/bg-21-1601-2024
<b>Technical note: A comparison of methods for estimating coccolith mass</b><br>
Celina Rebeca Valença, Luc Beaufort, Gustaaf Marinus Hallegraeff, and Marius Nils Müller<br>
Biogeosciences, 21, 1601–1611, https://doi.org/10.5194/bg-21-1601-2024, 2024<br>
Coccolithophores contribute to the global carbon cycle and their calcite structures (coccoliths) are used as a palaeoproxy to understand past oceanographic conditions. Here, we compared three frequently used methods to estimate coccolith mass from the model species Emiliania huxleyi and the results allow for a high level of comparability between the methods, facilitating future comparisons and consolidation of mass changes observed from ecophysiological and biogeochemical studies.
2024-03-28T05:12:53+01:00Regional assessment and uncertainty analysis of carbon and nitrogen balances at cropland scale using the ecosystem model LandscapeDNDC
https://doi.org/10.5194/bg-21-1563-2024
<b>Regional assessment and uncertainty analysis of carbon and nitrogen balances at cropland scale using the ecosystem model LandscapeDNDC</b><br>
Odysseas Sifounakis, Edwin Haas, Klaus Butterbach-Bahl, and Maria P. Papadopoulou<br>
Biogeosciences, 21, 1563–1581, https://doi.org/10.5194/bg-21-1563-2024, 2024<br>
We performed a full assessment of the carbon and nitrogen cycles of a cropland ecosystem. An uncertainty analysis and quantification of all carbon and nitrogen fluxes were deployed. The inventory simulations include greenhouse gas emissions of N2O, NH3 volatilization and NO3 leaching from arable land cultivation in Greece. The inventory also reports changes in soil organic carbon and nitrogen stocks in arable soils.
2024-03-27T05:12:53+01:00Thermal stratification and meromixis in four dilute temperate zone lakes
https://doi.org/10.5194/bg-21-1549-2024
<b>Thermal stratification and meromixis in four dilute temperate zone lakes</b><br>
Elizabeth D. Swanner, Chris Harding, Sajjad A. Akam, Ioan Lascu, Gabrielle Ledesma, Pratik Poudel, Heeyeon Sun, Samuel Duncanson, Karly Bandy, Alex Branham, Liza Bryant-Tapper, Tanner Conwell, Omri Jamison, and Lauren Netz<br>
Biogeosciences, 21, 1549–1562, https://doi.org/10.5194/bg-21-1549-2024, 2024<br>
Four lakes were thought to be permanently stratified. Years’ worth of data indicate only one lake is permanently stratified. Strong temperature gradients keep it stratified – unusual for a lake in a temperate climate. The lake has elevated oxygen concentrations within the temperature gradient. Rapid development of the gradient in the spring traps oxygen, and oxygen production by photosynthetic organisms during the summer adds more.
2024-03-25T05:12:53+01:00Relevance of near-surface soil moisture vs. terrestrial water storage for global vegetation functioning
https://doi.org/10.5194/bg-21-1533-2024
<b>Relevance of near-surface soil moisture vs. terrestrial water storage for global vegetation functioning</b><br>
Prajwal Khanal, Anne J. Hoek Van Dijke, Timo Schaffhauser, Wantong Li, Sinikka J. Paulus, Chunhui Zhan, and René Orth<br>
Biogeosciences, 21, 1533–1547, https://doi.org/10.5194/bg-21-1533-2024, 2024<br>
Water availability is essential for vegetation functioning, but the depth of vegetation water uptake is largely unknown due to sparse ground measurements. This study correlates vegetation growth with soil moisture availability globally to infer vegetation water uptake depth using only satellite-based data. We find that the vegetation water uptake depth varies across climate regimes and vegetation types and also changes during dry months at a global scale.
2024-03-22T05:12:53+01:00Loss of nitrogen via anaerobic ammonium oxidation (anammox) in the California Current system during the late Quaternary
https://doi.org/10.5194/bg-21-1517-2024
<b>Loss of nitrogen via anaerobic ammonium oxidation (anammox) in the California Current system during the late Quaternary</b><br>
Zoë Rebecca van Kemenade, Zeynep Erdem, Ellen Christine Hopmans, Jaap Smede Sinninghe Damsté, and Darci Rush<br>
Biogeosciences, 21, 1517–1532, https://doi.org/10.5194/bg-21-1517-2024, 2024<br>
The California Current system (CCS) hosts the eastern subtropical North Pacific oxygen minimum zone (ESTNP OMZ). This study shows anaerobic ammonium oxidizing (anammox) bacteria cause a loss of bioavailable nitrogen (N) in the ESTNP OMZ throughout the late Quaternary. Anammox occurred during both glacial and interglacial periods and was driven by the supply of organic matter and changes in ocean currents. These findings may have important consequences for biogeochemical models of the CCS.
2024-03-22T05:12:53+01:00Non-steady-state stomatal conductance modeling and its implications: from leaf to ecosystem
https://doi.org/10.5194/bg-21-1501-2024
<b>Non-steady-state stomatal conductance modeling and its implications: from leaf to ecosystem</b><br>
Ke Liu, Yujie Wang, Troy S. Magney, and Christian Frankenberg<br>
Biogeosciences, 21, 1501–1516, https://doi.org/10.5194/bg-21-1501-2024, 2024<br>
Stomata are pores on leaves that regulate gas exchange between plants and the atmosphere. Existing land models unrealistically assume stomata can jump between steady states when the environment changes. We implemented dynamic modeling to predict gradual stomatal responses at different scales. Results suggested that considering this effect on plant behavior patterns in diurnal cycles was important. Our framework also simplified simulations and can contribute to further efficiency improvements.
2024-03-21T05:12:53+01:00Oceanographic processes driving low-oxygen conditions inside Patagonian fjords
https://doi.org/10.5194/bg-21-1433-2024
<b>Oceanographic processes driving low-oxygen conditions inside Patagonian fjords</b><br>
Pamela Linford, Iván Pérez-Santos, Paulina Montero, Patricio A. Díaz, Claudia Aracena, Elías Pinilla, Facundo Barrera, Manuel Castillo, Aida Alvera-Azcárate, Mónica Alvarado, Gabriel Soto, Cécile Pujol, Camila Schwerter, Sara Arenas-Uribe, Pilar Navarro, Guido Mancilla-Gutiérrez, Robinson Altamirano, Javiera San Martín, and Camila Soto-Riquelme<br>
Biogeosciences, 21, 1433–1459, https://doi.org/10.5194/bg-21-1433-2024, 2024<br>
The Patagonian fjords comprise a world region where low-oxygen water and hypoxia conditions are observed. An in situ dataset was used to quantify the mechanism involved in the presence of these conditions in northern Patagonian fjords. Water mass analysis confirmed the contribution of Equatorial Subsurface Water in the advection of the low-oxygen water, and hypoxic conditions occurred when the community respiration rate exceeded the gross primary production.
2024-03-20T05:12:53+01:00Above- and belowground plant mercury dynamics in a salt marsh estuary in Massachusetts, USA
https://doi.org/10.5194/bg-21-1461-2024
<b>Above- and belowground plant mercury dynamics in a salt marsh estuary in Massachusetts, USA</b><br>
Ting Wang, Buyun Du, Inke Forbrich, Jun Zhou, Joshua Polen, Elsie M. Sunderland, Prentiss H. Balcom, Celia Chen, and Daniel Obrist<br>
Biogeosciences, 21, 1461–1476, https://doi.org/10.5194/bg-21-1461-2024, 2024<br>
The strong seasonal increases of Hg in aboveground biomass during the growing season and the lack of changes observed after senescence in this salt marsh ecosystem suggest physiologically controlled Hg uptake pathways. The Hg sources found in marsh aboveground tissues originate from a mix of sources, unlike terrestrial ecosystems, where atmospheric GEM is the main source. Belowground plant tissues mostly take up Hg from soils. Overall, the salt marsh currently serves as a small net Hg sink.
2024-03-20T05:12:53+01:00Distinct oxygenation modes of the Gulf of Oman over the past 43 000 years – a multi-proxy approach
https://doi.org/10.5194/bg-21-1477-2024
<b>Distinct oxygenation modes of the Gulf of Oman over the past 43 000 years – a multi-proxy approach</b><br>
Nicole Burdanowitz, Gerhard Schmiedl, Birgit Gaye, Philipp M. Munz, and Hartmut Schulz<br>
Biogeosciences, 21, 1477–1499, https://doi.org/10.5194/bg-21-1477-2024, 2024<br>
We analyse benthic foraminifera, nitrogen isotopes and lipids in a sediment core from the Gulf of Oman to investigate how the oxygen minimum zone (OMZ) and bottom water (BW) oxygenation have reacted to climatic changes since 43 ka. The OMZ and BW deoxygenation was strong during the Holocene, but the OMZ was well ventilated during the LGM period. We found an unstable mode of oscillating oxygenation states, from moderately oxygenated in cold stadials to deoxygenated in warm interstadials in MIS 3.
2024-03-20T05:12:53+01:00Synergistic use of Sentinel-2 and UAV-derived data for plant fractional cover distribution mapping of coastal meadows with digital elevation models
https://doi.org/10.5194/bg-21-1411-2024
<b>Synergistic use of Sentinel-2 and UAV-derived data for plant fractional cover distribution mapping of coastal meadows with digital elevation models</b><br>
Ricardo Martínez Prentice, Miguel Villoslada, Raymond D. Ward, Thaisa F. Bergamo, Chris B. Joyce, and Kalev Sepp<br>
Biogeosciences, 21, 1411–1431, https://doi.org/10.5194/bg-21-1411-2024, 2024<br>
Despite hosting a wide range of ecosystem services, coastal wetlands face threats from global changes. This study models the plant fractional cover of plant communities in Estonian coastal meadows with a synergistic use of drone, satellite imagery and digital elevation models. This approach highlights the significant contribution of digital elevation models to multispectral data, enabling the modelling of heterogeneous plant community distributions in such wetlands.
2024-03-19T05:12:53+01:00Modelled forest ecosystem carbon–nitrogen dynamics with integrated mycorrhizal processes under elevated CO2
https://doi.org/10.5194/bg-21-1391-2024
<b>Modelled forest ecosystem carbon–nitrogen dynamics with integrated mycorrhizal processes under elevated CO2</b><br>
Melanie A. Thurner, Silvia Caldararu, Jan Engel, Anja Rammig, and Sönke Zaehle<br>
Biogeosciences, 21, 1391–1410, https://doi.org/10.5194/bg-21-1391-2024, 2024<br>
Due to their crucial role in terrestrial ecosystems, we implemented mycorrhizal fungi into the QUINCY terrestrial biosphere model. Fungi interact with mineral and organic soil to support plant N uptake and, thus, plant growth. Our results suggest that the effect of mycorrhizal interactions on simulated ecosystem dynamics is minor under constant environmental conditions but necessary to reproduce and understand observed patterns under changing conditions, such as rising atmospheric CO2.
2024-03-19T05:12:53+01:00Moisture and temperature effects on the radiocarbon signature of respired carbon dioxide to assess stability of soil carbon in the Tibetan Plateau
https://doi.org/10.5194/bg-21-1277-2024
<b>Moisture and temperature effects on the radiocarbon signature of respired carbon dioxide to assess stability of soil carbon in the Tibetan Plateau</b><br>
Andrés Tangarife-Escobar, Georg Guggenberger, Xiaojuan Feng, Guohua Dai, Carolina Urbina-Malo, Mina Azizi-Rad, and Carlos A. Sierra<br>
Biogeosciences, 21, 1277–1299, https://doi.org/10.5194/bg-21-1277-2024, 2024<br>
Soil organic matter stability depends on future temperature and precipitation scenarios. We used radiocarbon (14C) data and model predictions to understand how the transit time of carbon varies under environmental change in grasslands and peatlands. Soil moisture affected the Δ14C of peatlands, while temperature did not have any influence. Our models show the correspondence between Δ14C and transit time and could allow understanding future interactions between terrestrial and atmospheric carbon
2024-03-18T05:12:53+01:00Variability and drivers of carbonate chemistry at shellfish aquaculture sites in the Salish Sea, British Columbia
https://doi.org/10.5194/bg-21-1323-2024
<b>Variability and drivers of carbonate chemistry at shellfish aquaculture sites in the Salish Sea, British Columbia</b><br>
Eleanor Simpson, Debby Ianson, Karen E. Kohfeld, Ana C. Franco, Paul A. Covert, Marty Davelaar, and Yves Perreault<br>
Biogeosciences, 21, 1323–1353, https://doi.org/10.5194/bg-21-1323-2024, 2024<br>
Shellfish aquaculture operates in nearshore areas where data on ocean acidification parameters are limited. We show daily and seasonal variability in pH and saturation states of calcium carbonate at nearshore aquaculture sites in British Columbia, Canada, and determine the contributing drivers of this variability. We find that nearshore locations have greater variability than open waters and that the uptake of carbon by phytoplankton is the major driver of pH and saturation state variability.
2024-03-18T05:12:53+01:00Resolving heterogeneous fluxes from tundra halves the growing season carbon budget
https://doi.org/10.5194/bg-21-1301-2024
<b>Resolving heterogeneous fluxes from tundra halves the growing season carbon budget</b><br>
Sarah M. Ludwig, Luke Schiferl, Jacqueline Hung, Susan M. Natali, and Roisin Commane<br>
Biogeosciences, 21, 1301–1321, https://doi.org/10.5194/bg-21-1301-2024, 2024<br>
Landscapes are often assumed to be homogeneous when using eddy covariance fluxes, which can lead to biases when calculating carbon budgets. In this study we report eddy covariance carbon fluxes from heterogeneous tundra. We used the footprints of each flux observation to unmix the fluxes coming from components of the landscape. We identified and quantified hot spots of carbon emissions in the landscape. Accurately scaling with landscape heterogeneity yielded half as much regional carbon uptake.
2024-03-18T05:12:53+01:00Frost matters: incorporating late-spring frost into a dynamic vegetation model regulates regional productivity dynamics in European beech forests
https://doi.org/10.5194/bg-21-1355-2024
<b>Frost matters: incorporating late-spring frost into a dynamic vegetation model regulates regional productivity dynamics in European beech forests </b><br>
Benjamin F. Meyer, Allan Buras, Konstantin Gregor, Lucia S. Layritz, Adriana Principe, Jürgen Kreyling, Anja Rammig, and Christian S. Zang<br>
Biogeosciences, 21, 1355–1370, https://doi.org/10.5194/bg-21-1355-2024, 2024<br>
Late-spring frost (LSF), critically low temperatures when trees have already flushed their leaves, results in freezing damage leaving trees with reduced ability to perform photosynthesis. Forests with a high proportion of susceptible species like European beech are particularly vulnerable. However, this process is rarely included in dynamic vegetation models (DVMs). We show that the effect on simulated productivity and biomass is substantial, warranting more widespread inclusion of LSF in DVMs.
2024-03-18T05:12:53+01:00Comparison of carbon and water fluxes and the drivers of ecosystem water use efficiency in a temperate rainforest and a peatland in southern South America
https://doi.org/10.5194/bg-21-1371-2024
<b>Comparison of carbon and water fluxes and the drivers of ecosystem water use efficiency in a temperate rainforest and a peatland in southern South America</b><br>
Jorge F. Perez-Quezada, David Trejo, Javier Lopatin, David Aguilera, Bruce Osborne, Mauricio Galleguillos, Luca Zattera, Juan L. Celis-Diez, and Juan J. Armesto<br>
Biogeosciences, 21, 1371–1389, https://doi.org/10.5194/bg-21-1371-2024, 2024<br>
For 8 years we sampled a temperate rainforest and a peatland in Chile to estimate their efficiency to capture carbon per unit of water lost. The efficiency is more related to the water lost than to the carbon captured and is mainly driven by evaporation instead of transpiration. This is the first report from southern South America and highlights that ecosystems might behave differently in this area, likely explained by the high annual precipitation (~ 2100 mm) and light-limited conditions.
2024-03-18T05:12:53+01:00Data-based investigation of the effects of canopy structure and shadows on chlorophyll fluorescence in a deciduous oak forest
https://doi.org/10.5194/bg-21-1259-2024
<b>Data-based investigation of the effects of canopy structure and shadows on chlorophyll fluorescence in a deciduous oak forest</b><br>
Hamadou Balde, Gabriel Hmimina, Yves Goulas, Gwendal Latouche, Abderrahmane Ounis, and Kamel Soudani<br>
Biogeosciences, 21, 1259–1276, https://doi.org/10.5194/bg-21-1259-2024, 2024<br>
We show that FyieldLIF was not correlated with SIFy at the diurnal timescale, and the diurnal patterns in SIF and PAR did not match under clear-sky conditions due to canopy structure. Φk was sensitive to canopy structure. RF models show that Φk can be predicted using reflectance in different bands. RF models also show that FyieldLIF was more sensitive to reflectance and radiation than SIF and SIFy, indicating that the combined effect of reflectance bands could hide the SIF physiological trait.
2024-03-15T05:12:53+01:00Technical note: Assessment of float pH data quality control methods – a case study in the subpolar northwest Atlantic Ocean
https://doi.org/10.5194/bg-21-1191-2024
<b>Technical note: Assessment of float pH data quality control methods – a case study in the subpolar northwest Atlantic Ocean</b><br>
Cathy Wimart-Rousseau, Tobias Steinhoff, Birgit Klein, Henry Bittig, and Arne Körtzinger<br>
Biogeosciences, 21, 1191–1211, https://doi.org/10.5194/bg-21-1191-2024, 2024<br>
The marine CO2 system can be measured independently and continuously by BGC-Argo floats since numerous pH sensors have been developed to suit these autonomous measurements platforms. By applying the Argo correction routines to float pH data acquired in the subpolar North Atlantic Ocean, we report the uncertainty and lack of objective criteria associated with the choice of the reference method as well the reference depth for the pH correction.
2024-03-13T05:12:53+01:00