Articles | Volume 17, issue 20
https://doi.org/10.5194/amt-17-6047-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/amt-17-6047-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Lower-cost eddy covariance for CO2 and H2O fluxes over grassland and agroforestry
Justus G. V. van Ramshorst
CORRESPONDING AUTHOR
Bioclimatology, Faculty of Forest Sciences and Forest Ecology, University of Göttingen, Büsgenweg 2, 37077 Göttingen, Germany
Quanterra Systems Ltd., Centenary House, Peninsula Park, Exeter, EX2 7XE, UK
Alexander Knohl
Bioclimatology, Faculty of Forest Sciences and Forest Ecology, University of Göttingen, Büsgenweg 2, 37077 Göttingen, Germany
Centre of Biodiversity and Sustainable Land Use (CBL), University of Göttingen, 37077 Göttingen, Germany
José Ángel Callejas-Rodelas
Bioclimatology, Faculty of Forest Sciences and Forest Ecology, University of Göttingen, Büsgenweg 2, 37077 Göttingen, Germany
Robert Clement
Quanterra Systems Ltd., Centenary House, Peninsula Park, Exeter, EX2 7XE, UK
Department of Geography, College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4RJ, UK
Timothy C. Hill
Department of Geography, College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4RJ, UK
Lukas Siebicke
Bioclimatology, Faculty of Forest Sciences and Forest Ecology, University of Göttingen, Büsgenweg 2, 37077 Göttingen, Germany
Christian Markwitz
Bioclimatology, Faculty of Forest Sciences and Forest Ecology, University of Göttingen, Büsgenweg 2, 37077 Göttingen, Germany
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A dataset expanding around seventy eight site-years was compiled, harmonized and presented. The dataset consisted in eddy covariance and meteorological measurements over four pairs of agroforestry and open cropland systems, and one pair of agroforestry and open grassland system. This is the first ever dataset compiling this type of data over temperate agroforestry systems.
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Jacob A. Nelson, Sophia Walther, Fabian Gans, Basil Kraft, Ulrich Weber, Kimberly Novick, Nina Buchmann, Mirco Migliavacca, Georg Wohlfahrt, Ladislav Šigut, Andreas Ibrom, Dario Papale, Mathias Göckede, Gregory Duveiller, Alexander Knohl, Lukas Hörtnagl, Russell L. Scott, Jiří Dušek, Weijie Zhang, Zayd Mahmoud Hamdi, Markus Reichstein, Sergio Aranda-Barranco, Jonas Ardö, Maarten Op de Beeck, Dave Billesbach, David Bowling, Rosvel Bracho, Christian Brümmer, Gustau Camps-Valls, Shiping Chen, Jamie Rose Cleverly, Ankur Desai, Gang Dong, Tarek S. El-Madany, Eugenie Susanne Euskirchen, Iris Feigenwinter, Marta Galvagno, Giacomo A. Gerosa, Bert Gielen, Ignacio Goded, Sarah Goslee, Christopher Michael Gough, Bernard Heinesch, Kazuhito Ichii, Marcin Antoni Jackowicz-Korczynski, Anne Klosterhalfen, Sara Knox, Hideki Kobayashi, Kukka-Maaria Kohonen, Mika Korkiakoski, Ivan Mammarella, Mana Gharun, Riccardo Marzuoli, Roser Matamala, Stefan Metzger, Leonardo Montagnani, Giacomo Nicolini, Thomas O'Halloran, Jean-Marc Ourcival, Matthias Peichl, Elise Pendall, Borja Ruiz Reverter, Marilyn Roland, Simone Sabbatini, Torsten Sachs, Marius Schmidt, Christopher R. Schwalm, Ankit Shekhar, Richard Silberstein, Maria Lucia Silveira, Donatella Spano, Torbern Tagesson, Gianluca Tramontana, Carlo Trotta, Fabio Turco, Timo Vesala, Caroline Vincke, Domenico Vitale, Enrique R. Vivoni, Yi Wang, William Woodgate, Enrico A. Yepez, Junhui Zhang, Donatella Zona, and Martin Jung
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Anas Emad and Lukas Siebicke
Atmos. Meas. Tech., 16, 41–55, https://doi.org/10.5194/amt-16-41-2023, https://doi.org/10.5194/amt-16-41-2023, 2023
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Florian Ellsäßer, Christian Stiegler, Alexander Röll, Tania June, Hendrayanto, Alexander Knohl, and Dirk Hölscher
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Jan Pisek, Angela Erb, Lauri Korhonen, Tobias Biermann, Arnaud Carrara, Edoardo Cremonese, Matthias Cuntz, Silvano Fares, Giacomo Gerosa, Thomas Grünwald, Niklas Hase, Michal Heliasz, Andreas Ibrom, Alexander Knohl, Johannes Kobler, Bart Kruijt, Holger Lange, Leena Leppänen, Jean-Marc Limousin, Francisco Ramon Lopez Serrano, Denis Loustau, Petr Lukeš, Lars Lundin, Riccardo Marzuoli, Meelis Mölder, Leonardo Montagnani, Johan Neirynck, Matthias Peichl, Corinna Rebmann, Eva Rubio, Margarida Santos-Reis, Crystal Schaaf, Marius Schmidt, Guillaume Simioni, Kamel Soudani, and Caroline Vincke
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Understory vegetation is the most diverse, least understood component of forests worldwide. Understory communities are important drivers of overstory succession and nutrient cycling. Multi-angle remote sensing enables us to describe surface properties by means that are not possible when using mono-angle data. Evaluated over an extensive set of forest ecosystem experimental sites in Europe, our reported method can deliver good retrievals, especially over different forest types with open canopies.
Jelka Braden-Behrens, Lukas Siebicke, and Alexander Knohl
Biogeosciences Discuss., https://doi.org/10.5194/bg-2020-398, https://doi.org/10.5194/bg-2020-398, 2020
Preprint withdrawn
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We use directly measured isotopic compositions and isoforcing values in combination with meteorological data and PBL height information to gain a better understanding of the variability of the isotopic composition of H2Ov. We directly compare the measured changes in isotopic composition with isoforcing-related changes (driven by local evapotranspiration ET). We conclude that it is important to account for PBL height when interpreting isoforcing data.
Yuan Zhang, Ana Bastos, Fabienne Maignan, Daniel Goll, Olivier Boucher, Laurent Li, Alessandro Cescatti, Nicolas Vuichard, Xiuzhi Chen, Christof Ammann, M. Altaf Arain, T. Andrew Black, Bogdan Chojnicki, Tomomichi Kato, Ivan Mammarella, Leonardo Montagnani, Olivier Roupsard, Maria J. Sanz, Lukas Siebicke, Marek Urbaniak, Francesco Primo Vaccari, Georg Wohlfahrt, Will Woodgate, and Philippe Ciais
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We improved the ORCHIDEE LSM by distinguishing diffuse and direct light in canopy and evaluated the new model with observations from 159 sites. Compared with the old model, the new model has better sunny GPP and reproduced the diffuse light fertilization effect observed at flux sites. Our simulations also indicate different mechanisms causing the observed GPP enhancement under cloudy conditions at different times. The new model has the potential to study large-scale impacts of aerosol changes.
Christian Markwitz, Alexander Knohl, and Lukas Siebicke
Biogeosciences, 17, 5183–5208, https://doi.org/10.5194/bg-17-5183-2020, https://doi.org/10.5194/bg-17-5183-2020, 2020
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Agroforestry has been shown to alter the microclimate and to lead to higher carbon sequestration above ground and in the soil. In this study, we investigated the impact of agroforestry systems on system-scale evapotranspiration (ET) due to concerns about increased water losses to the atmosphere. Results showed small differences in annual sums of ET over agroforestry relative to monoculture systems, indicating that agroforestry in Germany can be a land use alternative to monoculture agriculture.
Justus G. V. van Ramshorst, Miriam Coenders-Gerrits, Bart Schilperoort, Bas J. H. van de Wiel, Jonathan G. Izett, John S. Selker, Chad W. Higgins, Hubert H. G. Savenije, and Nick C. van de Giesen
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In this work we present experimental results of a novel actively heated fiber-optic (AHFO) observational wind-probing technique. We utilized a controlled wind-tunnel setup to assess both the accuracy and precision of AHFO under a range of operational conditions (wind speed, angles of attack and temperature differences). AHFO has the potential to provide high-resolution distributed observations of wind speeds, allowing for better spatial characterization of fine-scale processes.
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Short summary
In this work we present experimental field results of a lower-cost eddy covariance (LC-EC) system, which can measure the ecosystem exchange of carbon dioxide and water vapour with the atmosphere. During three field campaigns on a grassland and agroforestry grassland, we compared the LC-EC with a conventional eddy covariance (CON-EC) system. Our results show that LC-EC has the potential to measure EC fluxes at only approximately 25 % of the cost of a CON-EC system.
In this work we present experimental field results of a lower-cost eddy covariance (LC-EC)...