28 results on '"Marcin Jackowicz-Korczynski"'
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2. Vegetation type is an important predictor of the arctic summer land surface energy budget
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Jacqueline Oehri, Gabriela Schaepman-Strub, Jin-Soo Kim, Raleigh Grysko, Heather Kropp, Inge Grünberg, Vitalii Zemlianskii, Oliver Sonnentag, Eugénie S. Euskirchen, Merin Reji Chacko, Giovanni Muscari, Peter D. Blanken, Joshua F. Dean, Alcide di Sarra, Richard J. Harding, Ireneusz Sobota, Lars Kutzbach, Elena Plekhanova, Aku Riihelä, Julia Boike, Nathaniel B. Miller, Jason Beringer, Efrén López-Blanco, Paul C. Stoy, Ryan C. Sullivan, Marek Kejna, Frans-Jan W. Parmentier, John A. Gamon, Mikhail Mastepanov, Christian Wille, Marcin Jackowicz-Korczynski, Dirk N. Karger, William L. Quinton, Jaakko Putkonen, Dirk van As, Torben R. Christensen, Maria Z. Hakuba, Robert S. Stone, Stefan Metzger, Baptiste Vandecrux, Gerald V. Frost, Martin Wild, Birger Hansen, Daniela Meloni, Florent Domine, Mariska te Beest, Torsten Sachs, Aram Kalhori, Adrian V. Rocha, Scott N. Williamson, Sara Morris, Adam L. Atchley, Richard Essery, Benjamin R. K. Runkle, David Holl, Laura D. Riihimaki, Hiroki Iwata, Edward A. G. Schuur, Christopher J. Cox, Andrey A. Grachev, Joseph P. McFadden, Robert S. Fausto, Mathias Göckede, Masahito Ueyama, Norbert Pirk, Gijs de Boer, M. Syndonia Bret-Harte, Matti Leppäranta, Konrad Steffen, Thomas Friborg, Atsumu Ohmura, Colin W. Edgar, Johan Olofsson, and Scott D. Chambers
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Science - Abstract
An international team of researchers finds high potential for improving climate projections by a more comprehensive treatment of largely ignored Arctic vegetation types, underscoring the importance of Arctic energy exchange measuring stations.
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- 2022
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3. Earlier snowmelt may lead to late season declines in plant productivity and carbon sequestration in Arctic tundra ecosystems
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Donatella Zona, Peter M. Lafleur, Koen Hufkens, Barbara Bailey, Beniamino Gioli, George Burba, Jordan P. Goodrich, Anna K. Liljedahl, Eugénie S. Euskirchen, Jennifer D. Watts, Mary Farina, John S. Kimball, Martin Heimann, Mathias Göckede, Martijn Pallandt, Torben R. Christensen, Mikhail Mastepanov, Efrén López-Blanco, Marcin Jackowicz-Korczynski, Albertus J. Dolman, Luca Belelli Marchesini, Roisin Commane, Steven C. Wofsy, Charles E. Miller, David A. Lipson, Josh Hashemi, Kyle A. Arndt, Lars Kutzbach, David Holl, Julia Boike, Christian Wille, Torsten Sachs, Aram Kalhori, Xia Song, Xiaofeng Xu, Elyn R. Humphreys, Charles D. Koven, Oliver Sonnentag, Gesa Meyer, Gabriel H. Gosselin, Philip Marsh, and Walter C. Oechel
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Medicine ,Science - Abstract
Abstract Arctic warming is affecting snow cover and soil hydrology, with consequences for carbon sequestration in tundra ecosystems. The scarcity of observations in the Arctic has limited our understanding of the impact of covarying environmental drivers on the carbon balance of tundra ecosystems. In this study, we address some of these uncertainties through a novel record of 119 site-years of summer data from eddy covariance towers representing dominant tundra vegetation types located on continuous permafrost in the Arctic. Here we found that earlier snowmelt was associated with more tundra net CO2 sequestration and higher gross primary productivity (GPP) only in June and July, but with lower net carbon sequestration and lower GPP in August. Although higher evapotranspiration (ET) can result in soil drying with the progression of the summer, we did not find significantly lower soil moisture with earlier snowmelt, nor evidence that water stress affected GPP in the late growing season. Our results suggest that the expected increased CO2 sequestration arising from Arctic warming and the associated increase in growing season length may not materialize if tundra ecosystems are not able to continue sequestering CO2 later in the season.
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- 2022
- Full Text
- View/download PDF
4. Author Correction: The FLUXNET2015 dataset and the ONEFlux processing pipeline for eddy covariance data
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Gilberto Pastorello, Carlo Trotta, Eleonora Canfora, Housen Chu, Danielle Christianson, You-Wei Cheah, Cristina Poindexter, Jiquan Chen, Abdelrahman Elbashandy, Marty Humphrey, Peter Isaac, Diego Polidori, Markus Reichstein, Alessio Ribeca, Catharine van Ingen, Nicolas Vuichard, Leiming Zhang, Brian Amiro, Christof Ammann, M. Altaf Arain, Jonas Ardö, Timothy Arkebauer, Stefan K. Arndt, Nicola Arriga, Marc Aubinet, Mika Aurela, Dennis Baldocchi, Alan Barr, Eric Beamesderfer, Luca Belelli Marchesini, Onil Bergeron, Jason Beringer, Christian Bernhofer, Daniel Berveiller, Dave Billesbach, Thomas Andrew Black, Peter D. Blanken, Gil Bohrer, Julia Boike, Paul V. Bolstad, Damien Bonal, Jean-Marc Bonnefond, David R. Bowling, Rosvel Bracho, Jason Brodeur, Christian Brümmer, Nina Buchmann, Benoit Burban, Sean P. Burns, Pauline Buysse, Peter Cale, Mauro Cavagna, Pierre Cellier, Shiping Chen, Isaac Chini, Torben R. Christensen, James Cleverly, Alessio Collalti, Claudia Consalvo, Bruce D. Cook, David Cook, Carole Coursolle, Edoardo Cremonese, Peter S. Curtis, Ettore D’Andrea, Humberto da Rocha, Xiaoqin Dai, Kenneth J. Davis, Bruno De Cinti, Agnes de Grandcourt, Anne De Ligne, Raimundo C. De Oliveira, Nicolas Delpierre, Ankur R. Desai, Carlos Marcelo Di Bella, Paul di Tommasi, Han Dolman, Francisco Domingo, Gang Dong, Sabina Dore, Pierpaolo Duce, Eric Dufrêne, Allison Dunn, Jiří Dušek, Derek Eamus, Uwe Eichelmann, Hatim Abdalla M. ElKhidir, Werner Eugster, Cacilia M. Ewenz, Brent Ewers, Daniela Famulari, Silvano Fares, Iris Feigenwinter, Andrew Feitz, Rasmus Fensholt, Gianluca Filippa, Marc Fischer, John Frank, Marta Galvagno, Mana Gharun, Damiano Gianelle, Bert Gielen, Beniamino Gioli, Anatoly Gitelson, Ignacio Goded, Mathias Goeckede, Allen H. Goldstein, Christopher M. Gough, Michael L. Goulden, Alexander Graf, Anne Griebel, Carsten Gruening, Thomas Grünwald, Albin Hammerle, Shijie Han, Xingguo Han, Birger Ulf Hansen, Chad Hanson, Juha Hatakka, Yongtao He, Markus Hehn, Bernard Heinesch, Nina Hinko-Najera, Lukas Hörtnagl, Lindsay Hutley, Andreas Ibrom, Hiroki Ikawa, Marcin Jackowicz-Korczynski, Dalibor Janouš, Wilma Jans, Rachhpal Jassal, Shicheng Jiang, Tomomichi Kato, Myroslava Khomik, Janina Klatt, Alexander Knohl, Sara Knox, Hideki Kobayashi, Georgia Koerber, Olaf Kolle, Yoshiko Kosugi, Ayumi Kotani, Andrew Kowalski, Bart Kruijt, Julia Kurbatova, Werner L. Kutsch, Hyojung Kwon, Samuli Launiainen, Tuomas Laurila, Bev Law, Ray Leuning, Yingnian Li, Michael Liddell, Jean-Marc Limousin, Marryanna Lion, Adam J. Liska, Annalea Lohila, Ana López-Ballesteros, Efrén López-Blanco, Benjamin Loubet, Denis Loustau, Antje Lucas-Moffat, Johannes Lüers, Siyan Ma, Craig Macfarlane, Vincenzo Magliulo, Regine Maier, Ivan Mammarella, Giovanni Manca, Barbara Marcolla, Hank A. Margolis, Serena Marras, William Massman, Mikhail Mastepanov, Roser Matamala, Jaclyn Hatala Matthes, Francesco Mazzenga, Harry McCaughey, Ian McHugh, Andrew M. S. McMillan, Lutz Merbold, Wayne Meyer, Tilden Meyers, Scott D. Miller, Stefano Minerbi, Uta Moderow, Russell K. Monson, Leonardo Montagnani, Caitlin E. Moore, Eddy Moors, Virginie Moreaux, Christine Moureaux, J. William Munger, Taro Nakai, Johan Neirynck, Zoran Nesic, Giacomo Nicolini, Asko Noormets, Matthew Northwood, Marcelo Nosetto, Yann Nouvellon, Kimberly Novick, Walter Oechel, Jørgen Eivind Olesen, Jean-Marc Ourcival, Shirley A. Papuga, Frans-Jan Parmentier, Eugenie Paul-Limoges, Marian Pavelka, Matthias Peichl, Elise Pendall, Richard P. Phillips, Kim Pilegaard, Norbert Pirk, Gabriela Posse, Thomas Powell, Heiko Prasse, Suzanne M. Prober, Serge Rambal, Üllar Rannik, Naama Raz-Yaseef, Corinna Rebmann, David Reed, Victor Resco de Dios, Natalia Restrepo-Coupe, Borja R. Reverter, Marilyn Roland, Simone Sabbatini, Torsten Sachs, Scott R. Saleska, Enrique P. Sánchez-Cañete, Zulia M. Sanchez-Mejia, Hans Peter Schmid, Marius Schmidt, Karl Schneider, Frederik Schrader, Ivan Schroder, Russell L. Scott, Pavel Sedlák, Penélope Serrano-Ortíz, Changliang Shao, Peili Shi, Ivan Shironya, Lukas Siebicke, Ladislav Šigut, Richard Silberstein, Costantino Sirca, Donatella Spano, Rainer Steinbrecher, Robert M. Stevens, Cove Sturtevant, Andy Suyker, Torbern Tagesson, Satoru Takanashi, Yanhong Tang, Nigel Tapper, Jonathan Thom, Michele Tomassucci, Juha-Pekka Tuovinen, Shawn Urbanski, Riccardo Valentini, Michiel van der Molen, Eva van Gorsel, Ko van Huissteden, Andrej Varlagin, Joseph Verfaillie, Timo Vesala, Caroline Vincke, Domenico Vitale, Natalia Vygodskaya, Jeffrey P. Walker, Elizabeth Walter-Shea, Huimin Wang, Robin Weber, Sebastian Westermann, Christian Wille, Steven Wofsy, Georg Wohlfahrt, Sebastian Wolf, William Woodgate, Yuelin Li, Roberto Zampedri, Junhui Zhang, Guoyi Zhou, Donatella Zona, Deb Agarwal, Sebastien Biraud, Margaret Torn, and Dario Papale
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Science - Abstract
A Correction to this paper has been published: https://doi.org/10.1038/s41597-021-00851-9.
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- 2021
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5. Multi-year data-model evaluation reveals the importance of nutrient availability over climate in arctic ecosystem C dynamics
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Efrén López-Blanco, Marcin Jackowicz-Korczynski, Mikhail Mastepanov, Kirstine Skov, Andreas Westergaard-Nielsen, Mathew Williams, and Torben R Christensen
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arctic tundra ,Greenland ,net ecosystem exchange ,photosynthesis ,ecosystem respiration ,nutrient availability ,Environmental technology. Sanitary engineering ,TD1-1066 ,Environmental sciences ,GE1-350 ,Science ,Physics ,QC1-999 - Abstract
Arctic tundra is a globally important store for carbon (C). However, there is a lack of reference sites characterising C exchange dynamics across annual cycles. Based on the Greenland Ecosystem Monitoring (GEM) programme, here we present 9–11 years of flux and ecosystem data across the period 2008–2018 from two wetland sites in Greenland: Zackenberg (74°N) and Kobbefjord (64°N). The Zackenberg fen was a strong C sink despite its higher latitude and shorter growing seasons compared to the Kobbefjord fen. On average the ecosystem in Zackenberg took up ∼−50 g C m ^−2 yr ^−1 (range of +21 to −90 g C m ^−2 yr ^−1 ), more than twice that of Kobbefjord (mean ∼−18 g C m ^−2 yr ^−1 , and range of +41 to − 41 g C m ^−2 yr ^−1 ). The larger net carbon sequestration in Zackenberg fen was associated with higher leaf nitrogen (71%), leaf area index (140%), and plant quality (i.e. C:N ratio; 36%). Additional evidence from in-situ measurements includes 3 times higher levels of dissolved organic carbon in soils and 5 times more available plant nutrients, including dissolved organic nitrogen (N) and nitrates, in Zackenberg. Simulations using the soil-plant-atmosphere ecosystem model showed that Zackenberg’s stronger CO _2 sink could be related to measured differences in plant nutrients, and their effects on photosynthesis and respiration. The model explained 69% of the variability of net ecosystem exchange of CO _2 , 80% for photosynthesis and 71% for respiration over 11 years at Zackenberg, similar to previous results at Kobbefjord (73%, 73%, and 50%, respectively, over 8 years). We conclude that growing season limitations of plant phenology on net C uptake have been more than counterbalanced by the increased leaf nutrient content at the Zackenberg site.
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- 2020
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6. Rapid responses of permafrost and vegetation to experimentally increased snow cover in sub-arctic Sweden
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Margareta Johansson, Terry V Callaghan, Julia Bosiö, H Jonas Åkerman, Marcin Jackowicz-Korczynski, and Torben R Christensen
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snow manipulation ,sub-arctic permafrost ,active layer thickness ,vegetation changes ,Environmental technology. Sanitary engineering ,TD1-1066 ,Environmental sciences ,GE1-350 ,Science ,Physics ,QC1-999 - Abstract
Increased snow depth already observed, and that predicted for the future are of critical importance to many geophysical and biological processes as well as human activities. The future characteristics of sub-arctic landscapes where permafrost is particularly vulnerable will depend on complex interactions between snow cover, vegetation and permafrost. An experimental manipulation was, therefore, set up on a lowland peat plateau with permafrost, in northernmost Sweden, to simulate projected future increases in winter precipitation and to study their effects on permafrost and vegetation. After seven years of treatment, statistically significant differences between manipulated and control plots were found in mean winter ground temperatures, which were 1.5 ° C higher in manipulated plots. During the winter, a difference in minimum temperatures of up to 9 ° C higher could be found in individual manipulated plots compared with control plots. Active layer thicknesses increased at the manipulated plots by almost 20% compared with the control plots and a mean surface subsidence of 24 cm was recorded in the manipulated plots compared to 5 cm in the control plots. The graminoid Eriophorum vaginatum has expanded in the manipulated plots and the vegetation remained green longer in the season.
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- 2013
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7. Carbon uptake in Eurasian boreal forests dominates the high‐latitude net ecosystem carbon budget
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Jennifer D. Watts, Mary Farina, John S. Kimball, Luke D. Schiferl, Zhihua Liu, Kyle A. Arndt, Donatella Zona, Ashley Ballantyne, Eugénie S. Euskirchen, Frans‐Jan W. Parmentier, Manuel Helbig, Oliver Sonnentag, Torbern Tagesson, Janne Rinne, Hiroki Ikawa, Masahito Ueyama, Hideki Kobayashi, Torsten Sachs, Daniel F. Nadeau, John Kochendorfer, Marcin Jackowicz‐Korczynski, Anna Virkkala, Mika Aurela, Roisin Commane, Brendan Byrne, Leah Birch, Matthew S. Johnson, Nima Madani, Brendan Rogers, Jinyang Du, Arthur Endsley, Kathleen Savage, Ben Poulter, Zhen Zhang, Lori M. Bruhwiler, Charles E. Miller, Scott Goetz, and Walter C. Oechel
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CO ,Global and Planetary Change ,carbon budget ,remote sensing ,Arctic-boreal ,tundra ,Ecology ,Environmental Chemistry ,CH ,wetland ,General Environmental Science - Abstract
Arctic-boreal landscapes are experiencing profound warming, along with changes in ecosystem moisture status and disturbance from fire. This region is of global importance in terms of carbon feedbacks to climate, yet the sign (sink or source) and magnitude of the Arctic-boreal carbon budget within recent years remains highly uncertain. Here, we provide new estimates of recent (2003–2015) vegetation gross primary productivity (GPP), ecosystem respiration (Reco), net ecosystem CO2 exchange (NEE; Reco − GPP), and terrestrial methane (CH4) emissions for the Arctic-boreal zone using a satellite data-driven process-model for northern ecosystems (TCFM-Arctic), calibrated and evaluated using measurements from >60 tower eddy covariance (EC) sites. We used TCFM-Arctic to obtain daily 1-km2 flux estimates and annual carbon budgets for the pan-Arctic-boreal region. Across the domain, the model indicated an overall average NEE sink of −850 Tg CO2-C year−1. Eurasian boreal zones, especially those in Siberia, contributed to a majority of the net sink. In contrast, the tundra biome was relatively carbon neutral (ranging from small sink to source). Regional CH4 emissions from tundra and boreal wetlands (not accounting for aquatic CH4) were estimated at 35 Tg CH4-C year−1. Accounting for additional emissions from open water aquatic bodies and from fire, using available estimates from the literature, reduced the total regional NEE sink by 21% and shifted many far northern tundra landscapes, and some boreal forests, to a net carbon source. This assessment, based on in situ observations and models, improves our understanding of the high-latitude carbon status and also indicates a continued need for integrated site-to-regional assessments to monitor the vulnerability of these ecosystems to climate change.
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- 2023
8. Earlier snowmelt may lead to late season declines in plant productivity and carbon sequestration in Arctic tundra ecosystems
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Martijn Pallandt, Christian Wille, Charles D. Koven, Xia Song, S. C. Wofsy, Jennifer D. Watts, Mikhail Mastepanov, Walter C. Oechel, Anna K. Liljedahl, Peter M. Lafleur, Jordan P. Goodrich, Donatella Zona, Josh Hashemi, Marcin Jackowicz-Korczynski, Torben R. Christensen, David A. Lipson, Lars Kutzbach, Charles E. Miller, Philip Marsh, M. Goeckede, Gabriel Hould Gosselin, John S. Kimball, Xiaofeng Xu, Luca Belelli Marchesini, A. J. Dolman, Efrén López-Blanco, Oliver Sonnentag, George Burba, M. Farina, Aram Kalhori, Julia Boike, David Holl, Barbara A. Bailey, Martin Heimann, Roisin Commane, Eugénie S. Euskirchen, Elyn Humphreys, Gesa Meyer, Beniamino Gioli, Kyle A. Arndt, Torsten Sachs, Koen Hufkens, and Institute for Atmospheric and Earth System Research (INAR)
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1171 Geosciences ,Carbon Sequestration ,Life on Land ,Climate Change ,Carbon sequestration ,Soil ,Settore BIO/07 - ECOLOGIA ,Ecosystem ,Tundra ,Multidisciplinary ,Ecology ,Arctic Regions ,Lead (sea ice) ,Carbon Dioxide ,Plants ,15. Life on land ,Environmental sciences ,13. Climate action ,Plant productivity ,Snowmelt ,Environmental science ,Late season ,Seasons ,Climate sciences - Abstract
Arctic warming is affecting snow cover and soil hydrology, with consequences for carbon sequestration in tundra ecosystems. The scarcity of observations in the Arctic has limited our understanding of the impact of covarying environmental drivers on the carbon balance of tundra ecosystems. In this study, we address some of these uncertainties through a novel record of 119 site-years of summer data from eddy covariance towers representing dominant tundra vegetation types located on continuous permafrost in the Arctic. Here we found that earlier snowmelt was associated with more tundra net CO2 sequestration and higher gross primary productivity (GPP) only in June and July, but with lower net carbon sequestration and lower GPP in August. Although higher evapotranspiration (ET) can result in soil drying with the progression of the summer, we did not find significantly lower soil moisture with earlier snowmelt, nor evidence that water stress affected GPP in the late growing season. Our results suggest that the expected increased CO2 sequestration arising from Arctic warming and the associated increase in growing season length may not materialize if tundra ecosystems are not able to continue sequestering CO2 later in the season.
- Published
- 2022
9. The FLUXNET2015 dataset and the ONEFlux processing pipeline for eddy covariance data
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Eddy Moors, Uwe Eichelmann, Christian Brümmer, Stefano Minerbi, Barbara Marcolla, Gil Bohrer, Leonardo Montagnani, Üllar Rannik, Han Dolman, Janina Klatt, Samuli Launiainen, Elizabeth A. Walter-Shea, Nina Buchmann, Hank A. Margolis, Beniamino Gioli, Peter S. Curtis, Margaret S. Torn, Gabriela Posse, Luca Belelli Marchesini, Gianluca Filippa, Kenneth J. Davis, Leiming Zhang, Alexander Graf, Ray Leuning, Andrew Feitz, Simone Sabbatini, Harry McCaughey, Werner Eugster, Juha Pekka Tuovinen, Timothy J. Arkebauer, N. N. Vygodskaya, Adam J. Liska, Rosvel Bracho, Sebastian Wolf, Marc Aubinet, Jiří Dušek, Eugénie Paul-Limoges, Christof Ammann, Daniel Berveiller, Zoran Nesic, Giacomo Nicolini, Jaclyn Hatala Matthes, Russell L. Scott, David E. Reed, Frans-Jan W. Parmentier, Changliang Shao, Penélope Serrano-Ortiz, Yingnian Li, Jason Beringer, Marc Fischer, Deb Agarwal, Rasmus Fensholt, Russell K. Monson, Agnès de Grandcourt, Stefan K. Arndt, Timo Vesala, Uta Moderow, Joseph Verfaillie, Mika Aurela, Bev Law, Nina Hinko-Najera, Taro Nakai, Richard P. Phillips, Lindsay B. Hutley, Benjamin Loubet, Michele Tomassucci, Ayumi Kotani, Hans Peter Schmid, Raimundo Cosme de Oliveira, Anatoly A. Gitelson, Domenico Vitale, Regine Maier, Caitlin E. Moore, Xiaoqin Dai, Damien Bonal, John M. Frank, Yuelin Li, Christopher M. Gough, Shijie Han, Shirley A. Papuga, Edoardo Cremonese, Shawn Urbanski, Sébastien C. Biraud, Scott D. Miller, Mana Gharun, Annalea Lohila, Ian McHugh, Giovanni Manca, Bert Gielen, Wayne S. Meyer, Pierpaolo Duce, Bruce D. Cook, Carsten Gruening, Hiroki Ikawa, B.R. Reverter, Marian Pavelka, Andrew M. S. McMillan, Gang Dong, Isaac Chini, Kimberly A. Novick, Dalibor Janouš, Anne De Ligne, E. Beamesderfer, Marty Humphrey, Virginie Moreaux, Christian Wille, Markus Hehn, Hideki Kobayashi, Allen H. Goldstein, Walter C. Oechel, Richard Silberstein, Francisco Domingo, Francesco Mazzenga, Elise Pendall, Juha Hatakka, Lutz Merbold, Xingguo Han, Daniela Famulari, Carlo Trotta, Naama Raz-Yaseef, Dario Papale, Jean Marc Ourcival, Benoit Burban, Pavel Sedlák, Diego Polidori, Asko Noormets, Huimin Wang, Birger Ulf Hansen, Thomas Grünwald, Caroline Vincke, Robert M. Stevens, Carole Coursolle, D. P. Billesbach, Karl Schneider, Guoyi Zhou, Marcin Jackowicz-Korczynski, Paul V. Bolstad, Iris Feigenwinter, Shiping Chen, Julia Boike, Ivan Schroder, D. S. Christianson, Junhui Zhang, Pierre Cellier, Catharine van Ingen, Andrej Varlagin, A. Ribeca, Claudia Consalvo, Derek Eamus, Jason Brodeur, Alan G. Barr, Denis Loustau, Andreas Ibrom, Ankur R. Desai, Andrew E. Suyker, Efrén López-Blanco, Peter Cale, Nicola Arriga, William J. Massman, Abdelrahman Elbashandy, Yoshiko Kosugi, Pauline Buysse, Cove Sturtevant, T. A. Black, Housen Chu, David R. Bowling, Sabina Dore, Albin Hammerle, Tilden P. Meyers, M. Altaf Arain, Hatim Abdalla M. ElKhidir, Ignacio Goded, Roberto Zampedri, Alessio Collalti, Torsten Sachs, Tuomas Laurila, Cristina Poindexter, E. Canfora, Alexander Knohl, Donatella Spano, Silvano Fares, Scott R. Saleska, Michiel K. van der Molen, Suzanne M. Prober, Marryanna Lion, Steven C. Wofsy, Michael L. Goulden, Matthew Northwood, Antje Lucas-Moffat, Christine Moureaux, Jean-Marc Limousin, Sara H. Knox, Damiano Gianelle, Olaf Kolle, Jørgen E. Olesen, Mikhail Mastepanov, Bernard Heinesch, Christian Bernhofer, Peter D. Blanken, Hyojung Kwon, Georg Wohlfahrt, Peili Shi, Yann Nouvellon, Allison L. Dunn, Onil Bergeron, Mauro Cavagna, Heiko Prasse, Natalia Restrepo-Coupe, Yanhong Tang, Donatella Zona, Andrew S. Kowalski, Eric Dufrêne, Kim Pilegaard, Serena Marras, Yongtao He, Brent E. Ewers, Siyan Ma, Jean Marc Bonnefond, Jonas Ardö, Ko van Huissteden, Roser Matamala, Robin Weber, Nigel J. Tapper, Humberto Ribeiro da Rocha, Eva van Gorsel, Torbern Tagesson, Frederik Schrader, Frank Tiedemann, Myroslava Khomik, Torben R. Christensen, Jonathan E. Thom, James Cleverly, Víctor Resco de Dios, Ivan Shironya, Jeffrey P. Walker, You Wei Cheah, Ana López-Ballesteros, Georgia R. Koerber, J. William Munger, Shicheng Jiang, Johannes Lüers, Bruno De Cinti, Gilberto Pastorello, David R. Cook, Werner L. Kutsch, Paul Di Tommasi, Nicolas Delpierre, Peter Isaac, Carlos Marcelo Di Bella, Jiquan Chen, Craig Macfarlane, Dennis D. Baldocchi, William Woodgate, Riccardo Valentini, Marilyn Roland, Ladislav Šigut, Tomomichi Kato, Sebastian Westermann, Ivan Mammarella, Bart Kruijt, Marta Galvagno, Marius Schmidt, Serge Rambal, J. Kurbatova, Sean P. Burns, Ettore D'Andrea, Chad Hanson, Vincenzo Magliulo, Anne Griebel, Brian D. Amiro, M. Goeckede, Enrique P. Sánchez-Cañete, Thomas L. Powell, Marcelo D. Nosetto, Cacilia Ewenz, Michael J. Liddell, Satoru Takanashi, Lukas Hörtnagl, Zulia Mayari Sanchez-Mejia, W.W.P. Jans, N. Pirk, Johan Neirynck, Rainer Steinbrecher, Lukas Siebicke, Matthias Peichl, Rachhpal S. Jassal, Costantino Sirca, Earth and Climate, Earth Sciences, Institute for Atmospheric and Earth System Research (INAR), INAR Physics, Micrometeorology and biogeochemical cycles, Viikki Plant Science Centre (ViPS), Ecosystem processes (INAR Forest Sciences), Lawrence Berkeley National Laboratory [Berkeley] (LBNL), Università degli studi della Tuscia [Viterbo], California State University [Sacramento], Michigan State University System, University of Virginia, Max Planck Institute for Biogeochemistry (MPI-BGC), Max-Planck-Gesellschaft, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Chinese Academy of Sciences [Beijing] (CAS), University of Manitoba [Winnipeg], Agroscope, McMaster University [Hamilton, Ontario], Lund University [Lund], University of Nebraska–Lincoln, University of Nebraska System, University of Melbourne, University of Antwerp (UA), Université de Liège, Finnish Meteorological Institute (FMI), University of California [Berkeley] (UC Berkeley), University of California (UC), University of Saskatchewan [Saskatoon] (U of S), Peoples Friendship University of Russia [RUDN University] (RUDN), The University of Western Australia (UWA), Technische Universität Dresden = Dresden University of Technology (TU Dresden), Ecologie Systématique et Evolution (ESE), AgroParisTech-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), University of British Columbia (UBC), University of Colorado [Colorado Springs] (UCCS), Ohio State University [Columbus] (OSU), Humboldt University Of Berlin, University of Minnesota System, SILVA (SILVA), AgroParisTech-Université de Lorraine (UL)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Interactions Sol Plante Atmosphère (UMR ISPA), Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), University of Utah, University of Central Florida [Orlando] (UCF), Thunen Institute of Climate-Smart Agriculture, Department of Environmental Systems Science [ETH Zürich] (D-USYS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Ecologie des forêts de Guyane (UMR ECOFOG), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-AgroParisTech-Université de Guyane (UG)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Ecologie fonctionnelle et écotoxicologie des agroécosystèmes (ECOSYS), AgroParisTech-Université Paris-Saclay-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Fondazione Edmund Mach - Edmund Mach Foundation [Italie] (FEM), Aarhus University [Aarhus], University of Technology Sydney (UTS), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), NASA Goddard Space Flight Center (GSFC), Argonne National Laboratory [Lemont] (ANL), Université Laval [Québec] (ULaval), Universidade de São Paulo = University of São Paulo (USP), Pennsylvania State University (Penn State), Penn State System, Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut Agro Montpellier, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), University of Wisconsin-Madison, Vrije Universiteit Amsterdam [Amsterdam] (VU), Centro de Investigaciones Biológicas (CSIC), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Shanxi University (SXU), Worcester State University [Worcester], Czech Academy of Sciences [Prague] (CAS), Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Université Paul-Valéry - Montpellier 3 (UPVM)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut Agro - Montpellier SupAgro, Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), UCL - SST/ELI/ELIE - Environmental Sciences, GILBERTO PASTORELLO, Lawrence Berkeley National Laboratory, THOMAS ANDREW BLACK, University of British Columbia, PETER D. BLANKEN, University of Colorado, GIL BOHRER, Ohio State University, JULIA BOIKE, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research / Humboldt-Universität zu Berlin, PAUL V. BOLSTAD, University of Minnesota, JEAN-MARC BONNEFOND, ISPA Bordeaux Sciences Agro, DAVID R. BOWLING, University of Utah, ROSVEL BRACHO, University of Florida, JASON BRODEUR, McMaster University, CHRISTIAN BRÜMMER, Thünen Institute of Climate-Smart Agriculture, NINA BUCHMANN, ETH Zurich, BENOIT BURBAN, INRAE UMR ECOFOG, AGNES DE GRANDCOURT, UMR Eco&Sols, CIRAD, ANNE DE LIGNE, University of Liege, RAIMUNDO COSME DE OLIVEIRA JUNIOR, CPATU, HAN DOLMAN, Universiteit Amsterdam, FRANCISCO DOMINGO, CSIC, GANG DONG, Shanxi University, SABINA DORE, HydroFocus, PIERPAOLO DUCE, National Research Council of Italy, MARTA GALVAGNO, Environmental Protection Agency of Aosta Valley, MANA GHARUN, ETH Zurich, DAMIANO GIANELLE, Fondazione Edmund Mach, MARCIN JACKOWICZ-KORCZYNSKI, Lund University / Aarhus University, DALIBOR JANOUS, Global Change Research Institute of the Czech Academy of Sciences, WILMA JANS, Wageningen University and Research, RACHHPAL JASSAL, University of British Columbia, SHICHENG JIANG, Northeast Normal University, ANA LÓPEZ-BALLESTEROS, Trinity College Dublin, EFRÉN LÓPEZ-BLANCO, Aarhus University, BENJAMIN LOUBET, Université Paris-Saclay, DENIS LOUSTAU, ISPA - INRA, JOHANNES LÜERS, University of Bayreuth, JOHAN NEIRYNCK, Research Institute for Nature and Forest, ZORAN NESIC, University of British Columbia, GIACOMO NICOLINI, University of Tuscia / CMCC, ASKO NOORMETS, Texas A&M University, MATTHEW NORTHWOOD, Charles Darwin University, KIMBERLY NOVICK, Indiana University Bloomington, MARILYN ROLAND, University of Antwerp, SIMONE SABBATINI, University of Tuscia, TORSTEN SACHS, GFZ German Research Centre for Geosciences, SCOTT R. SALESKA, University of Arizona, ENRIQUE P. SÁNCHEZ-CAÑETE, University of Granada / CEAMA-IISTA, ZULIA M. SANCHEZ-MEJIA, Instituto Tecnológico de Sonora, RAINER STEINBRECHER, Karlsruhe Institute of Technology, ROBERT M. STEVENS, Sentek Pty Ltd, COVE STURTEVANT, National Ecological Observatory Network Program, ANDY SUYKER, University of Nebraska-Lincoln, TORBERN TAGESSON, Lund University / University of Copenhagen, SATORU TAKANASHI, Forestry and Forest Products Research Institute, DOMENICO VITALE, University of Tuscia / CMCC, NATALIA VYGODSKAYA, Russian Academy of Sciences, JEFFREY P. WALKER, Monash University, ELIZABETH WALTER-SHEA, University of Nebraska-Lincoln, HUIMIN WANG, Chinese Academy of Sciences, ROBIN WEBER, University of California Berkeley, SEBASTIAN WESTERMANN, Instituto Nacional de Tecnologia Agropecuaria (INTA), CHRISTIAN WILLE, GFZ German Research Centre for Geosciences, STEVEN WOFSY, Harvard University, GEORG WOHLFAHRT, University of Innsbruck, SEBASTIAN WOLF, ETH Zurich, WILLIAM WOODGATE, CSIRO Land and Water, YUELIN LI, Chinese Academy of Sciences, DONATELLA ZONA, San Diego State University / University of Sheffield, DEB AGARWAL, Lawrence Berkeley National Laboratory, SEBASTIEN BIRAUD, Lawrence Berkeley National Laboratory, MARGARET TORN, Lawrence Berkeley National Laboratory, DARIO PAPALE, University of Tuscia / CMCC., ALLISON DUNN, Worcester State University, JIRÍ DUSEK, Global Change Research Institute of the Czech Academy of Sciences, DEREK EAMUS, University of Technology Sydney, UWE EICHELMANN, Technische Universität Dresden, HOUSEN CHU, Lawrence Berkeley National Laboratory, DANIELLE CHRISTIANSON, Lawrence Berkeley National Laboratory, YOU-WEI CHEAH, Lawrence Berkeley National Laboratory, CRISTINA POINDEXTER, California State University, JIQUAN CHEN, Michigan State University, ABDELRAHMAN ELBASHANDY, Lawrence Berkeley National Laboratory, MARTY HUMPHREY, University of Virginia, PETER ISAAC, TERN Ecosystrem Processes, DIEGO POLIDORI, University of Tuscia / CMCC, ALESSIO RIBECA, University of Tuscia / CMCC, CATHARINE VAN INGEN, Lawrence Berkeley National Laboratory, LEIMINGZ HANG, Chinese Academy of Sciences, BRIAN AMIRO, University of Manitoba, CHRISTOF AMMANN, Agroscope Research Institute, M. ALTAF ARAIN, McMaster University, JONAS ARDÖ, Lund University, TIMOTHY ARKEBAUER, University of Nebraska-Lincoln, STEFAN K. ARNDT, The University of Melbourne, NICOLA ARRIGA, University of Antwerp / Joint Research Centre, MARC AUBINET, University of Liege, MIKA AURELA, Finnish Meteorological Institute, DENNIS BALDOCCHI, University of California Berkeley, ALAN BARR, University of Saskatchewan / Environment and Climate Change Canada, DAMIEN BONAL, Université de Lorraine, SEAN P. BURNS, University of Colorado / National Center for Atmospheric Research, PAULINE BUYSSE, Université Paris-Saclay, PETER CALE, Australian Landscape Trust, MAURO CAVAGNA, Fondazione Edmund Mach, PIERRE CELLIER, Université Paris-Saclay, SHIPING CHEN, Chinese Academy of Sciences, ISAAC CHINI, Fondazione Edmund Mach, TORBEN R . CHRISTENSEN, Aarhus University, JAMES CLEVERLY, University of Technology Sydney, ALESSIO COLLALTI, University of Tuscia / National Research Council of Italy, CLAUDIA CONSALVO, University of Tuscia / National Research Council of Italy, BRUCE D. COOK, NASA Goddard Space Flight Center, DAVID COOK, Argonne National Laboratory, CAROLE COURSOLLE, Natural Resources Canada / Université Laval, EDOARDO CREMONESE, Climate Change Unit, PETER S. CURTIS, Ohio State University, ETTORE DANDREA, National Research Council of Italy, HUMBERTO DA ROCHA, USP, XIAOQIN DAI, Chinese Academy of Sciences, KENNETH J. DAVIS, The Pennsylvania State University, BRUNO DE CINTI, National Research Council of Italy, NICOLAS DELPIERRE, Université Paris-Saclay, ANKUR R . DESAI, University of Wisconsin-Madison, CARLOS MARCELO DI BELLA, Facultad de Agronomía, UBA, Buenos Aires., PAUL DI TOMMASI, National Research Council of Italy, ERIC DUFRÊNE, Université Paris-Saclay, MARIUS SCHMIDT, Agrosphere (IBG3), HATIM ABDALLA M. ELKHIDIR, ElObeid Research Station, WERNER EUGSTER, ETH Zurich, CACILIA M. EWENZ, TERN Ecosystem Processes Central Node, BRENT EWERS, University of Wyoming, DANIELA FAMULARI, National Research Council of Italy, SILVANO FARES, National Research Council of Italy / Research Centre for Forestry and Wood, IRIS FEIGENWINTER, ETH Zurich, ANDREW FEITZ, Geoscience Australia, RASMUS FENSHOLT, University of Copenhagen, GIANLUCA FILIPPA, Environmental Protection Agency of Aosta Valley, MARC FISCHER, Lawrence Berkeley National Laboratory, JOHN FRANK, USDA Forest Service, BERT GIELEN, University of Antwerp, BENIAMINO GIOLI, National Research Council of Italy, ANATOLY GITELSON, University of Nebraska-Lincoln, IGNACIO BALLARIN GODED, Joint Research Centre, MATHIAS GOECKEDE, University of Nebraska-Lincoln, ALLEN H. GOLDSTEIN, University of California Berkeley, CHRISTOPHER M. GOUGH, Virginia Commonwealth University, MICHAEL L. GOULDEN, University of California, ALEXANDER GRAF, Forschungszentrum Jülich, ANNE GRIEBEL, The University of Melbourne, CARSTEN GRUENING, Joint Research Centre, THOMAS GRÜNWALD, Technische Universität Dresden, ALBIN HAMMERLE, University of Innsbruck, SHIJIE HAN, Henan University / Chinese Academy of Sciences, XINGGUO HAN, Chinese Academy of Sciences, BIRGER ULF HANSEN, University of Copenhagen, CHAD HANSON, Oregon State University, JUHA HATAKKA, Finnish Meteorological Institute, YONGTAO HE, Chinese Academy of Sciences / University of Chinese Academy of Sciences, MARKUS HEHN, Technische Universität Dresden, BERNARD HEINESCH, University of Liege, NINA HINKO-NAJERA, The University of Melbourne, LUKAS HÖRTNAGL, ETH Zurich, LINDSAY HUTLEY, Charles Darwin University, ANDREAS IBROM, Technical University of Denmark, HIROKI IKAWA, National Agriculture and Food Research Organization, TOMOMICHI KATO, Hokkaido University, MYROSLAVA KHOMIK, McMaster University / Geography and Environmental Management, JANINA KLATT, Karlsruhe Institute of Technology, ALEXANDER KNOHL, University of Goettingen, SARA KNOX, The University of British Columbia, HIDEKI KOBAYASHI, Institute of Arctic Climate and Environment Research, GEORGIA KOERBER, University of Adelaide, OLAF KOLLE, Max Planck Institute for Biogeochemistry, YOSHIKO KOSUGI, Kyoto University, AYUMI KOTANI, Nagoya University, ANDREW KOWALSKI, University of Granada, BART KRUIJT, Wageningen University, JULIA KURBATOVA, Russian Academy of Sciences, WERNER L. KUTSCH, ICOS ERIC, HYOJUNG KWON, Oregon State University, SAMULI LAUNIAINEN, Natural Resources Institute Finland, TUOMAS LAURILA, Finnish Meteorological Institute, BEV LAW, Oregon State University, RAY LEUNING, In memoriam, YINGNIAN LI, Chinese Academy of Sciences, MICHAEL LIDDELL, James Cook University, JEAN-MARC LIMOUSIN, Univ Montpellier, KARL SCHNEIDER, University of Cologne, MARRYANNA LION, Forest Research Institute Malaysia, ADAM J. LISKA, University of Nebraska-Lincoln, ANNALEA LOHILA, Finnish Meteorological Institute / University of Helsinki, ANTJE LUCAS-MOFFAT, Thünen Institute of Climate-Smart Agriculture / Centre for Agrometeorological Research, SIYAN MA, University of California Berkeley, CRAIG MACFARLANE, CSIRO Land and Water, VINCENZO MAGLIULO, National Research Council of Italy, REGINE MAIER, ETH Zurich, IVAN MAMMARELLA, University of Helsinki, GIOVANNI MANCA, Joint Research Centre, BARBARA MARCOLLA, Fondazione Edmund Mach, HANK A . MARGOLIS, Université Laval, SERENA MARRAS, CMCC / University of Sassari, WILLIAM MASSMAN, USDA Forest Service, MIKHAIL MASTEPANOV, Aarhus University / University of Oulu, ROSER MATAMALA, Argonne National Laboratory, JACLYN HATALA MATTHES, Wellesley College, FRANCESCO MAZZENGA, National Research Council of Italy, HARRY MCCAUGHEY, Queen’s University, IAN MCHUGH, The University of Melbourne, ANDREW M. S. MCMILLAN, Environmental Analytics NZ, LUTZ MERBOLD, International Livestock Research Institute, WAYNE MEYER, University of Adelaide, TILDEN MEYERS, NOAA/OAR/Air Resources Laboratory, SCOTT D. MILLER, State University of New York at Albany, STEFANO MINERBI, Forest Department of South Tyrol, UTA MODEROW, Technische Universität Dresden, RUSSELL K. MONSON, University of Arizona, LEONARDO MONTAGNANI, Forest Department of South Tyrol / Free University of Bolzano, CAITLIN E. MOORE, University of Illinois at Urbana-Champaign, EDDY MOORS, IHE Delft / VU Amsterdam, VIRGINIE MOREAUX, ISPA / University Grenoble Alpes, CHRISTINE MOUREAUX, University of Liege, J. WILLIAM MUNGER, Harvard University, TARO NAKAI, National Taiwan University / University of Alaska Fairbanks, MARCELO NOSETTO, Instituto de Matemática Aplicada San Luis / UNER, YANN NOUVELLON, Univ Montpellier-CIRAD-INRA-IRD-Montpellier SupAgro, WALTER OECHEL, San Diego State University / University of Exeter, JORGEN EIVIND OLESEN, Aarhus University, JEAN-MARC OURCIVAL, Univ Montpellier, SHIRLEY A. PAPUGA, Wayne State University, FRANS-JAN PARMENTIER, Lund University / University of Oslo, EUGENIE PAUL-LIMOGES, University of Zurich, MARIAN PAVELKA, Global Change Research Institute of the Czech Academy of Sciences, MATTHIAS PEICHL, Swedish University of Agricultural Sciences, ELISE PENDALL, Western Sydney University, RICHARD P. PHILLIPS, Indiana University Bloomington, KIM PILEGAARD, Technical University of Denmark, NORBERT PIRK, Lund University / CSIRO Land and Water, GABRIELA POSSE, Instituto Nacional de Tecnologia Agropecuaria (INTA), THOMAS POWELL, Lawrence Berkeley National Laboratory, HEIKO PRASSE, Technische Universität Dresden, SUZANNE M. PROBER, CSIRO Land and Water, SERGE RAMBAL, Univ Montpellier, ÜLLAR RANNIK, University of Helsinki, DAVID REED, Michigan State University, VICTOR RESCO DE DIOS, Western Sydney University / Southwest University of Science and Technology, NATALIA RESTREPO-COUPE, University of Arizona, BORJA R. REVERTER, Universidade Federal da Paraiba, HANS PETER SCHMID, Karlsruhe Institute of Technology, FREDERIK SCHRADER, Federal Research Institute of Rural Areas, IVAN SCHRODER, Geoscience Australia, RUSSELL L. SCOTT, Southwest Watershed Research Center, PAVEL SEDLÁK, Global Change Research Institute of the Czech Academy of Sciences / Institute of Atmospheric Physics of the Czech Academy of Sciences, PENÉLOPE SERRANO-ORTÍZ, CEAMA-IISTA / University of Granada, CHANGLIANG SHAO, Chinese Academy of Agricultural Sciences, PEILI SHI, Chinese Academy of Sciences, IVAN SHIRONYA, Russian Academy of Sciences, LUKAS SIEBICKE, Bioclimatology, University of Goettingen, LADISLAV SIGUT, Global Change Research Institute of the Czech Academy of Sciences, RICHARD SILBERSTEIN, University of Western Australia / Edith Cowan University, COSTANTINO SIRCA, CMCC / University of Sassari, DONATELLA SPANO, CMCC / University of Sassari, YANHONG TANG, Peking University, NIGEL TAPPER, Monash University, JONATHAN THOM, University of Wisconsin-Madison, FRANK TIEDEMANN, University of Goettingen, MICHELE TOMASSUCCI, University of Tuscia / Terrasystem srl, JUHA-PEKKA TUOVINEN, Finnish Meteorological Institute, SHAWN URBANSKI, Rocky Mountain Research Station, RICCARDO VALENTINI, University of Tuscia / CMCC, MICHIEL VAN DER MOLEN, Wageningen University, EVA VAN GORSEL, Australian National University Canberra, KO VAN HUISSTEDEN, Vrije Universiteit Amsterdam, ANDREJ VARLAGIN, Russian Academy of Sciences, JOSEPH VERFAILLIE, University of California Berkeley, TIMO VESALA, University of Helsinki, CAROLINE VINCKE, Chinese Academy of Sciences, ROBERTO ZAMPEDRI, Fondazione Edmund Mach, JUNHUI ZHANG, Chinese Academy of Sciences, GUOYI ZHOU, Nanjing University of Information Science & Technology, NAAMA RAZ-YASEEF, Lawrence Berkeley National Laboratory, ERIC BEAMESDERFER, McMaster University, CARLO TROTTA, University of Tuscia, ELEONORA CANFORA, University of Tuscia / CMCC, LUCA BELELLI MARCHESINI, Fondazione Edmund Mach / RUDN University, ONIL BERGERON, Ministère du Développement durable de l’Environnement et de la Lutte contre les changements climatiques, JASON BERINGER, University of Western Australia, CHRISTIAN BERNHOFER, Technische Universität Dresden, DANIEL BERVEILLER, Université Paris-Saclay, and DAVE BILLESBACH, University of Nebraska-Lincoln
- Subjects
Meteorologie en Luchtkwaliteit ,Data Descriptor ,010504 meteorology & atmospheric sciences ,Settore AGR/05 - ASSESTAMENTO FORESTALE E SELVICOLTURA ,dataset provides ecosystem ,UNCERTAINTY ,Eddy covariance ,Observation météorologique ,01 natural sciences ,ecosystem-scale data ,lcsh:Science ,SITES ,Energy ,Respiration ,Statistics ,Uncertainty ,Carbon cycle ,Biological measurements ,Terrestrial biome ,RESPIRATION ,gapfilling ,[SDE]Environmental Sciences ,Assimilation ,Anhídrid carbònic ,ddc:500 ,Net ecosystem exchange ,Écosystème ,STORAGE ,Information Systems ,Statistics and Probability ,ecosystem approaches [EN] ,Meteorology and Air Quality ,ASSIMILATION ,Library and Information Sciences ,Education ,collection [EN] ,Donnée climatique ,Data collection ,Water ,15. Life on land ,Earth system science ,Climate Resilience ,Klimaatbestendigheid ,lcsh:Q ,processing ,Climate sciences ,Ecophysiology ,Storage ,Oceanography, Hydrology, Water Resources ,010501 environmental sciences ,CARBON-DIOXIDE ,ENERGY-BALANCE CLOSURE ,ddc:550 ,Échange d'énergie ,FLUXNET2015 ,Biosphere ,Energy balance closure ,fluxnet ,Computer Science Applications ,Collecte de données ,Energia ,P01 - Conservation de la nature et ressources foncières ,Statistics, Probability and Uncertainty ,INTERANNUAL VARIABILITY ,Eddy Covariance ,SDG 6 - Clean Water and Sanitation ,Engineering sciences. Technology ,Sensoriamento Remoto ,FLUX ,1171 Geosciences ,Consistency (database systems) ,eau ,Life Science ,Time series ,Remote sensing studies ,Measurement device ,0105 earth and related environmental sciences ,Remote sensing ,Ecosystem respiration and photosynthetic ,WIMEK ,NET ECOSYSTEM EXCHANGE ,Pipeline (software) ,Environmental sciences ,Metadata ,Earth sciences ,Carbon dioxide ,13. Climate action ,Environmental science ,Probability and Uncertainty ,Water Systems and Global Change ,Dioxyde de carbone - Abstract
The FLUXNET2015 dataset provides ecosystem-scale data on CO2, water, and energy exchange between the biosphere and the atmosphere, and other meteorological and biological measurements, from 212 sites around the globe (over 1500 site-years, up to and including year 2014). These sites, independently managed and operated, voluntarily contributed their data to create global datasets. Data were quality controlled and processed using uniform methods, to improve consistency and intercomparability across sites. The dataset is already being used in a number of applications, including ecophysiology studies, remote sensing studies, and development of ecosystem and Earth system models. FLUXNET2015 includes derived-data products, such as gap-flled time series, ecosystem respiration and photosynthetic uptake estimates, estimation of uncertainties, and metadata about the measurements, presented for the frst time in this paper. In addition, 206 of these sites are for the frst time distributed under a Creative Commons (CC-BY 4.0) license. This paper details this enhanced dataset and the processing methods, now made available as open-source codes, making the dataset more accessible, transparent, and reproducible., European Union (EU), United States Department of Energy (DOE)
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- 2020
10. Multiple Ecosystem Effects of Extreme Weather Events in the Arctic
- Author
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Marcin Jackowicz-Korczynski, J. Scheller, Torben R. Christensen, Kirstine Skov, Efrén López-Blanco, M. Scheel, K. Langley, Melissa J. Murphy, Jakob Abermann, Magnus Lund, and Mikhail Mastepanov
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FLUX ,extreme events ,010504 meteorology & atmospheric sciences ,Climate change ,010501 environmental sciences ,SEDIMENT ,Atmospheric sciences ,01 natural sciences ,Thermokarst ,PERMAFROST ,Extreme weather ,METHANE ,RIVER ,Environmental Chemistry ,Ecosystem ,Precipitation ,long-term observations ,EXCHANGE ,Ecology, Evolution, Behavior and Systematics ,0105 earth and related environmental sciences ,geography ,CLIMATE-CHANGE ,geography.geographical_feature_category ,ecosystem impacts ,Ecology ,Arctic ecosystems ,ICE ,Global warming ,Tundra ,TUNDRA ,climate change ,Snowmelt ,SPATIOTEMPORAL VARIABILITY ,Environmental science - Abstract
The Arctic is getting warmer and wetter. Here, we document two independent examples of how associated extreme precipitation patterns have severe implications for high Arctic ecosystems. The events stand out in a 23-year record of continuous observations of a wide range of ecosystem parameters and act as an early indication of conditions projected to increase in the future. In NE Greenland, August 2015, one-quarter of the average annual precipitation fell during a 9-day intensive rain event. This ranked number one for daily sums during the 1996–2018 period and caused a strong and prolonged reduction in solar radiation decreasing CO2 uptake in the order of 18–23 g C m−2, a reduction comparable to typical annual C budgets in Arctic tundra. In a different type of event, but also due to changed weather patterns, an extreme snow melt season in 2018 triggered a dramatic gully thermokarst causing rapid transformation in ecosystem functioning from consistent annual ecosystem CO2 uptake and low methane exchange to highly elevated methane release, net source of CO2, and substantial export of organic carbon downstream as riverine and coastal input. In addition to climate warming alone, more frequent occurrence of extreme weather patterns will have large implications for otherwise undisturbed tundra ecosystems including their element transport and carbon interactions with the atmosphere and ocean.
- Published
- 2021
11. Multi-year data-model evaluation reveals the importance of nutrient availability over climate in arctic ecosystem C dynamics
- Author
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Mathew Williams, Kirstine Skov, Torben R. Christensen, Marcin Jackowicz-Korczynski, Andreas Westergaard-Nielsen, Mikhail Mastepanov, and Efrén López-Blanco
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geography ,geography.geographical_feature_category ,photosynthesis ,Ecosystem respiration ,010504 meteorology & atmospheric sciences ,Renewable Energy, Sustainability and the Environment ,net ecosystem exchange ,Greenland ,Public Health, Environmental and Occupational Health ,Growing season ,Wetland ,010501 environmental sciences ,01 natural sciences ,Tundra ,Nutrient ,Agronomy ,Dissolved organic carbon ,Environmental science ,Nutrient availability ,Ecosystem ,arctic tundra ,Leaf area index ,0105 earth and related environmental sciences ,General Environmental Science - Abstract
Arctic tundra is a globally important store for carbon (C). However, there is a lack of reference sites characterising C exchange dynamics across annual cycles. Based on the Greenland Ecosystem Monitoring (GEM) programme, here we present 9–11 years of flux and ecosystem data across the period 2008–2018 from two wetland sites in Greenland: Zackenberg (74°N) and Kobbefjord (64°N). The Zackenberg fen was a strong C sink despite its higher latitude and shorter growing seasons compared to the Kobbefjord fen. On average the ecosystem in Zackenberg took up ∼−50 g C m−2 yr−1 (range of +21 to −90 g C m−2 yr−1), more than twice that of Kobbefjord (mean ∼−18 g C m−2 yr−1, and range of +41 to − 41 g C m−2 yr−1). The larger net carbon sequestration in Zackenberg fen was associated with higher leaf nitrogen (71%), leaf area index (140%), and plant quality (i.e. C:N ratio; 36%). Additional evidence from in-situ measurements includes 3 times higher levels of dissolved organic carbon in soils and 5 times more available plant nutrients, including dissolved organic nitrogen (N) and nitrates, in Zackenberg. Simulations using the soil-plant-atmosphere ecosystem model showed that Zackenberg’s stronger CO2 sink could be related to measured differences in plant nutrients, and their effects on photosynthesis and respiration. The model explained 69% of the variability of net ecosystem exchange of CO2, 80% for photosynthesis and 71% for respiration over 11 years at Zackenberg, similar to previous results at Kobbefjord (73%, 73%, and 50%, respectively, over 8 years). We conclude that growing season limitations of plant phenology on net C uptake have been more than counterbalanced by the increased leaf nutrient content at the Zackenberg site.
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- 2020
12. Enriched nutrient availability strengthens the net C uptake of the northernmost ecosystem station in Greenland
- Author
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Efrén López-Blanco, Marcin Jackowicz-Korczynski, Mikhail Mastepanov, Kirstine Skov, Andreas Westergaard-Nielsen, Mathew Williams, and Torben R. Christensen
- Abstract
Although the Arctic tundra is an essential contributor to the global carbon (C) cycle, there is a lack of reference sites from where full C exchange dynamics can be characterized under harsh conditions and remoteness. The Greenland Ecosystem Monitoring (GEM) programme efforts have envisioned integrated and long-term activities to contribute to the basic scientific understanding of the Arctic and their responses to climate changes. Here we present 20+ years across the 2008-2018 period of C flux and ancillary data from two twin ecosystem stations in Greenland: Zackenberg (74°N) and Kobbefjord (64°N). In this project we show that Zackenberg fen has a significant higher C sink strength in a higher latitude during regularly shorter growing seasons compared to Kobbefjord fen. This ecosystem acted as a sink of CO2 uptaking on average -50 g C m-2 (range of +21 to -90 g C m-2), more than twice compared to Kobbefjord (-18 g C m-2 as average and range of +41 to -41 g C m-2). We found that Zackenberg is a nutrient richer fen - the increased C uptake strength is associated with 3 times higher levels in soils of dissolved organic carbon and 5 times more plant nutrients, including dissolved organic nitrogen, nitrates. Additional evidences from in-situ sampling point to higher leaf area index (140%), foliar nitrogen (71%), and leaf mass per area (5%) in the northernmost site supporting the nutrient richer hypothesis. To test this overarching hypothesis, we further used the Soil-Plant-Atmosphere (SPA) model. We can explain ~68%, ~80% and ~67% of the variability of daily net ecosystem exchange of CO2, photosynthesis and respiration respectively applying the model parameterization previously used in Kobbefjord but with increases in initial C stocks, leaf mass per area, N content and Q10 of foliar and root respiration rates. Therefore, we conclude that the limitations of plant phenology timing in Zackenberg regarding net C uptake have not only been counterbalanced but also intensified due to richer compositions of nutrients and minerals. More high-temporal monitoring activities in Arctic ecosystems are needed not only to allow straightforward comparisons of key biogeochemical processes but also to help us understand the underlying differences in sensitive and rapidly changing ecosystems.
- Published
- 2020
13. Refining the role of phenology in regulating gross ecosystem productivity across European peatlands
- Author
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Amy Pickard, Magnus Lund, Marcin Jackowicz-Korczynski, Annalea Lohila, Mikko Peltoniemi, Franziska Koebsch, Maiju Linkosalmi, Järvi Järveoja, Mats Nilsson, Kerry J. Dinsmore, Martin Maddison, Matthias Peichl, Fraser Leith, Eeva-Stiina Tuittila, Kari Minkkinen, Johannes Wilhelmus Maria Pullens, Ali Nadir Arslan, Ülo Mander, Mika Aurela, Ivan Mammarella, Damiano Gianelle, Pavel Alekseychik, Aino Korrensalo, Carole Helfter, Oliver Sonnentag, Institute for Atmospheric and Earth System Research (INAR), Micrometeorology and biogeochemical cycles, INAR Physics, Doctoral Programme in Atmospheric Sciences, Department of Forest Sciences, Kari Minkkinen / Principal Investigator, and Forest Ecology and Management
- Subjects
0106 biological sciences ,Peat ,010504 meteorology & atmospheric sciences ,Climate Change ,Climate change ,Growing season ,NORTHERN PEATLAND ,Canopy greenness ,010603 evolutionary biology ,01 natural sciences ,Ecology and Environment ,Structural equation modeling ,CO2 EXCHANGE ,Moderation ,Peatland C cycle ,Settore BIO/07 - ECOLOGIA ,medicine ,Environmental Chemistry ,Ecosystem ,Photosynthesis ,Commonality analysis ,TEMPERATURE ,0105 earth and related environmental sciences ,General Environmental Science ,Abiotic component ,Global and Planetary Change ,4112 Forestry ,photosynthesis ,Ecology ,Phenology ,CARBON-DIOXIDE EXCHANGE ,AREA ,Mediation ,Vegetation ,15. Life on land ,Seasonality ,medicine.disease ,VARIABILITY ,RESPIRATION ,13. Climate action ,DIGITAL REPEAT PHOTOGRAPHY ,1181 Ecology, evolutionary biology ,GROWING-SEASON ,Environmental science ,Seasons - Abstract
The role of plant phenology as regulator for gross ecosystem productivity (GEP) in peatlands is empirically not well constrained. This is because proxies to track vegetation development with daily coverage at the ecosystem scale have only recently become available and the lack of such data has hampered the disentangling of biotic and abiotic effects. This study aimed at unraveling the mechanisms that regulate the seasonal variation in GEP across a network of eight European peatlands. Therefore, we described phenology with canopy greenness derived from digital repeat photography and disentangled the effects of radiation, temperature and phenology on GEP with commonality analysis and structural equation modeling. The resulting relational network could not only delineate direct effects but also accounted for possible effect combinations such as interdependencies (mediation) and interactions (moderation). We found that peatland GEP was controlled by the same mechanisms across all sites: phenology constituted a key predictor for the seasonal variation in GEP and further acted as distinct mediator for temperature and radiation effects on GEP. In particular, the effect of air temperature on GEP was fully mediated through phenology, implying that direct temperature effects representing the thermoregulation of photosynthesis were negligible. The tight coupling between temperature, phenology and GEP applied especially to high latitude and high altitude peatlands and during phenological transition phases. Our study highlights the importance of phenological effects when evaluating the future response of peatland GEP to climate change. Climate change will affect peatland GEP especially through changing temperature patterns during plant-phenologically sensitive phases in high latitude and high altitude regions.
- Published
- 2019
14. Author Correction
- Author
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Pierpaolo Duce, B.R. Reverter, Bruce D. Cook, Marian Pavelka, Lindsay B. Hutley, Francesco Mazzenga, Caroline Vincke, Benoit Burban, Damiano Gianelle, Üllar Rannik, William J. Massman, Claudia Consalvo, Scott R. Saleska, D. P. Billesbach, Guoyi Zhou, Julia Boike, Michiel K. van der Molen, Werner Eugster, Hyojung Kwon, Thomas Grünwald, Thomas L. Powell, T. A. Black, Caitlin E. Moore, Albin Hammerle, Yingnian Li, Cristina Poindexter, Uwe Eichelmann, Marcelo D. Nosetto, Xiaoqin Dai, Cacilia Ewenz, Gilberto Pastorello, Carlos Marcelo Di Bella, Damien Bonal, Stefano Minerbi, Rosvel Bracho, Kim Pilegaard, Serena Marras, Michael J. Liddell, Mika Aurela, N. Pirk, Shawn Urbanski, Scott D. Miller, Janina Klatt, Eugénie Paul-Limoges, Jean-Marc Limousin, Hideki Kobayashi, Juha Hatakka, Georg Wohlfahrt, Diego Polidori, Mana Gharun, Olaf Kolle, Jørgen E. Olesen, Peili Shi, Yann Nouvellon, Johan Neirynck, Rainer Steinbrecher, Lukas Siebicke, Satoru Takanashi, Eva van Gorsel, Domenico Vitale, Regine Maier, Hans Peter Schmid, Raimundo Cosme de Oliveira, Torben R. Christensen, Giovanni Manca, Elizabeth A. Walter-Shea, Leonardo Montagnani, Jonathan E. Thom, James Cleverly, Andrew Feitz, Nina Buchmann, Andrew M. S. McMillan, N. N. Vygodskaya, E. Canfora, Richard Silberstein, David E. Reed, Marc Fischer, Ankur R. Desai, Leiming Zhang, Alexander Graf, Sébastien C. Biraud, Samuli Launiainen, Siyan Ma, Bart Kruijt, Carlo Trotta, Nicola Arriga, Christopher M. Gough, Elise Pendall, Peter S. Curtis, Margaret S. Torn, Gabriela Posse, Ivan Shironya, Silvano Fares, You Wei Cheah, Karl Schneider, Robin Weber, D. S. Christianson, Carsten Gruening, Hiroki Ikawa, Christine Moureaux, Paul V. Bolstad, Lukas Hörtnagl, Zulia Mayari Sanchez-Mejia, W.W.P. Jans, Alan G. Barr, Sebastian Wolf, Marc Aubinet, Christof Ammann, Penélope Serrano-Ortiz, Timothy J. Arkebauer, Shicheng Jiang, Han Dolman, Iris Feigenwinter, Junhui Zhang, A. Ribeca, Ana López-Ballesteros, Johannes Lüers, Chad Hanson, Hank A. Margolis, Nicolas Delpierre, Onil Bergeron, Mauro Cavagna, Jiří Dušek, Benjamin Loubet, Jason Brodeur, M. Altaf Arain, Kimberly A. Novick, Dalibor Janouš, Anne De Ligne, Marty Humphrey, Christian Wille, Daniel Berveiller, Changliang Shao, Pauline Buysse, Kenneth J. Davis, Annalea Lohila, Deb Agarwal, Ian McHugh, Ray Leuning, Anne Griebel, Natalia Restrepo-Coupe, Russell L. Scott, Russell K. Monson, Christian Brümmer, Dennis D. Baldocchi, Brian D. Amiro, Andrew E. Suyker, Naama Raz-Yaseef, Timo Vesala, David R. Cook, William Woodgate, Rasmus Fensholt, Uta Moderow, Richard P. Phillips, Stefan K. Arndt, Xingguo Han, Jason Beringer, Riccardo Valentini, Robert M. Stevens, Luca Belelli Marchesini, Shirley A. Papuga, Gianluca Filippa, Roser Matamala, John M. Frank, Peter Isaac, Werner L. Kutsch, Paul Di Tommasi, Yuelin Li, Andrej Varlagin, Ladislav Šigut, Francisco Domingo, E. Beamesderfer, Edoardo Cremonese, Eddy Moors, Joseph Verfaillie, Huimin Wang, Jiquan Chen, M. Goeckede, Craig Macfarlane, Enrique P. Sánchez-Cañete, Harry McCaughey, Tomomichi Kato, Dario Papale, Jean Marc Ourcival, Birger Ulf Hansen, Pierre Cellier, Bev Law, Derek Eamus, Carole Coursolle, Myroslava Khomik, Wayne S. Meyer, Taro Nakai, Mikhail Mastepanov, Nina Hinko-Najera, Peter Cale, Donatella Spano, Beniamino Gioli, Gang Dong, David R. Bowling, Sabina Dore, Shiping Chen, Isaac Chini, Jeffrey P. Walker, Eric Dufrêne, Sebastian Westermann, Marcin Jackowicz-Korczynski, Marryanna Lion, Barbara Marcolla, Marius Schmidt, Serge Rambal, Víctor Resco de Dios, Jean Marc Bonnefond, Ivan Mammarella, Hatim Abdalla M. ElKhidir, Ko van Huissteden, Suzanne M. Prober, Gil Bohrer, Markus Reichstein, Heiko Prasse, Nigel J. Tapper, Corinna Rebmann, J. Kurbatova, Abdelrahman Elbashandy, J. William Munger, Catharine van Ingen, Humberto Ribeiro da Rocha, Andreas Ibrom, Sean P. Burns, Simone Sabbatini, Marilyn Roland, Zoran Nesic, Tuomas Laurila, Giacomo Nicolini, Bruno De Cinti, Jaclyn Hatala Matthes, Georgia R. Koerber, Yoshiko Kosugi, Efrén López-Blanco, Cove Sturtevant, Matthew Northwood, Ettore D'Andrea, Torsten Sachs, Housen Chu, Matthias Peichl, Nicolas Vuichard, Alexander Knohl, Steven C. Wofsy, Michael L. Goulden, Vincenzo Magliulo, Antje Lucas-Moffat, Peter D. Blanken, Donatella Zona, Allison L. Dunn, Yanhong Tang, Marta Galvagno, Rachhpal S. Jassal, Jonas Ardö, Torbern Tagesson, Frederik Schrader, Ignacio Goded, Costantino Sirca, Shijie Han, Markus Hehn, Allen H. Goldstein, Bernard Heinesch, Christian Bernhofer, Yongtao He, Brent E. Ewers, Adam J. Liska, Michele Tomassucci, Virginie Moreaux, Denis Loustau, Agnès de Grandcourt, Tilden P. Meyers, Roberto Zampedri, Alessio Collalti, Sara H. Knox, Ayumi Kotani, Anatoly A. Gitelson, Andrew S. Kowalski, Walter C. Oechel, Lutz Merbold, Daniela Famulari, Pavel Sedlák, Asko Noormets, Juha Pekka Tuovinen, Frans-Jan W. Parmentier, Bert Gielen, Ivan Schroder, Earth Sciences, Earth and Climate, and UCL - SST/ELI/ELIE - Environmental Sciences
- Subjects
Data descriptor ,Statistics and Probability ,Code development ,010504 meteorology & atmospheric sciences ,Pipeline (computing) ,Science ,0207 environmental engineering ,Eddy covariance ,ComputingMilieux_LEGALASPECTSOFCOMPUTING ,02 engineering and technology ,Library and Information Sciences ,01 natural sciences ,Education ,ddc:550 ,020701 environmental engineering ,Author Correction ,0105 earth and related environmental sciences ,Information retrieval ,Published Erratum ,Substitution (logic) ,Statistics ,Carbon cycle ,Computer Science Applications ,Environmental sciences ,Earth sciences ,Probability and Uncertainty ,ddc:500 ,Statistics, Probability and Uncertainty ,Climate sciences ,Downscaling ,Information Systems - Abstract
The following authors were omitted from the original version of this Data Descriptor: Markus Reichstein and Nicolas Vuichard. Both contributed to the code development and N. Vuichard contributed to the processing of the ERA-Interim data downscaling. Furthermore, the contribution of the co-author Frank Tiedemann was re-evaluated relative to the colleague Corinna Rebmann, both working at the same sites, and based on this re-evaluation a substitution in the co-author list is implemented (with Rebmann replacing Tiedemann). Finally, two affiliations were listed incorrectly and are corrected here (entries 190 and 193). The author list and affiliations have been amended to address these omissions in both the HTML and PDF versions. © 2021, This is a U.S. government work and not under copyright protection in the U.S.; foreign copyright protection may apply.
- Published
- 2021
15. Ecosystem carbon response of an Arctic peatland to simulated permafrost thaw
- Author
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Timo Oksanen, Annalea Lohila, Christina Biasi, Marcin Jackowicz-Korczynski, Torben R. Christensen, Claire C. Treat, Hannu Nykänen, V. Palonen, Carolina Voigt, Maxim Dorodnikov, Pertti J. Martikainen, Mikhail Mastepanov, Markku Oinonen, Richard E. Lamprecht, Maija E. Marushchak, and Amelie Lindgren
- Subjects
0106 biological sciences ,hiilidioksidi ,Peat ,010504 meteorology & atmospheric sciences ,Permafrost ,ikirouta ,Atmospheric sciences ,01 natural sciences ,Methane ,CO2 EXCHANGE ,climate warming ,PALSA MIRE ,chemistry.chemical_compound ,Dissolved organic carbon ,General Environmental Science ,kasvihuoneilmiö ,Global and Planetary Change ,CLIMATE-CHANGE ,Ecology ,Arctic Regions ,methane oxidation ,hiilen kierto ,permafrost-carbon-feedback ,Plants ,mesocosm ,CO ,ORGANIC-MATTER ,kasvihuonekaasut ,CH4 FLUXES ,greenhouse gas ,NORTHERN PEATLANDS ,Carbon dioxide ,CO2 ,Oxidation-Reduction ,Biogeochemical cycle ,TUNDRA SOILS ,Climate Change ,ta1172 ,ta1171 ,010603 evolutionary biology ,metaani ,Carbon Cycle ,Greenhouse Gases ,METHANE EMISSIONS ,Environmental Chemistry ,0105 earth and related environmental sciences ,Atmosphere ,15. Life on land ,Carbon Dioxide ,WATER-TABLE ,EXTRACTION METHOD ,Arctic ,chemistry ,13. Climate action ,Greenhouse gas ,Environmental science - Abstract
Permafrost peatlands are biogeochemical hot spots in the Arctic as they store vast amounts of carbon. Permafrost thaw could release part of these long-term immobile carbon stocks as the greenhouse gases (GHGs) carbon dioxide (CO 2 ) and methane (CH 4 ) to the atmosphere, but how much, at which time-span and as which gaseous carbon species is still highly uncertain. Here we assess the effect of permafrost thaw on GHG dynamics under different moisture and vegetation scenarios in a permafrost peatland. A novel experimental approach using intact plant–soil systems (mesocosms) allowed us to simulate permafrost thaw under near-natural conditions. We monitored GHG flux dynamics via high-resolution flow-through gas measurements, combined with detailed monitoring of soil GHG concentration dynamics, yielding insights into GHG production and consumption potential of individual soil layers. Thawing the upper 10–15 cm of permafrost under dry conditions increased CO 2 emissions to the atmosphere (without vegetation: 0.74 ± 0.49 vs. 0.84 ± 0.60 g CO 2 –C m −2 day −1 ; with vegetation: 1.20 ± 0.50 vs. 1.32 ± 0.60 g CO 2 –C m −2 day −1 , mean ± SD, pre- and post-thaw, respectively). Radiocarbon dating ( 14 C) of respired CO 2 , supported by an independent curve-fitting approach, showed a clear contribution (9%–27%) of old carbon to this enhanced post-thaw CO 2 flux. Elevated concentrations of CO 2 , CH 4 , and dissolved organic carbon at depth indicated not just pulse emissions during the thawing process, but sustained decomposition and GHG production from thawed permafrost. Oxidation of CH 4 in the peat column, however, prevented CH 4 release to the atmosphere. Importantly, we show here that, under dry conditions, peatlands strengthen the permafrost–carbon feedback by adding to the atmospheric CO 2 burden post-thaw. However, as long as the water table remains low, our results reveal a strong CH 4 sink capacity in these types of Arctic ecosystems pre- and post-thaw, with the potential to compensate part of the permafrost CO 2 losses over longer timescales.
- Published
- 2019
16. Controls of spatial and temporal variability in CH4 flux in a high arctic fen over three years
- Author
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Marcin Jackowicz-Korczynski, Torben R. Christensen, Julie Maria Falk, Mikhail Mastepanov, Niels Martin Schmidt, Kirstine Skov, Lena Ström, and Magnus Lund
- Subjects
Growing season ,CH4 flux ,Atmospheric sciences ,Spatial variability ,Eriophorum ,NORTHERN MINNESOTA ,ORGANIC-CARBON ,STABLE CARBON ,Environmental Chemistry ,Ecosystem ,VEGETATION TYPES ,CARBON TURNOVER ,Earth-Surface Processes ,Water Science and Technology ,Hydrology ,biology ,CONTROLLING METHANE EMISSIONS ,Vegetation ,biology.organism_classification ,TUNDRA ,SOIL ,Productivity (ecology) ,Arctic ,Arctic wetlands ,Environmental science ,VASCULAR PLANTS ,CO2 ,Substrate availability ,Ecosystem respiration - Abstract
The aim of this study was to establish the main drivers of the spatial variability in growing season CH4 flux within an arctic wetland ecosystem. During 3 years (2011–2013) we measured CH4 flux and potential drivers, e.g., CO2 fluxes (net ecosystem exchange (NEE), gross primary productivity (GPP) and ecosystem respiration), temperature, water table depth, pore-water concentration of organic acids (e.g., acetate) and the vascular plant composition and density. The study included 16–20 main plots (Cmain) and in 2013 also experimental plots (10 excluded muskoxen grazing, 9 snow fence and 10 automated chamber plots) distributed over 0.3 km2. The results show a 1.8-times difference in CH4 flux magnitude inter-annually and 9- to 35-times spatially (depending on year and treatment). During all 3 years GPP was a strong driver of the variability in Cmain plots. Accordingly, the plant productivity related variables NEE, GPP and acetate were singled out as the strongest drivers of the variability in 2013, when all variables were measured on a majority of the plots. These variables were equally strong drivers of the spatial variability in CH4 flux regardless of whether experimental plots were included in the analysis or not. The density of Eriophorum scheuchzeri was the strongest driver of the spatial variability in NEE, GPP and acetate. In conclusion, changes in vegetation composition or productivity of wet arctic ecosystems will have large impacts on their carbon balance and CH4 flux, irrespective of whether these changes are driven directly by climate change or by biotic interactions, such as grazing.
- Published
- 2015
17. Increased nitrous oxide emissions from Arctic peatlands after permafrost thaw
- Author
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Mikhail Mastepanov, Amelie Lindgren, Marcin Jackowicz-Korczynski, Teemu Tahvanainen, Lars Granlund, Torben R. Christensen, Carolina Voigt, Pertti J. Martikainen, Richard E. Lamprecht, Maija E. Marushchak, Christina Biasi, and Ympäristö- ja biotieteiden laitos / Toiminta
- Subjects
Peat ,tundra ,010504 meteorology & atmospheric sciences ,Soil science ,N2O EMISSIONS ,Permafrost ,Atmospheric sciences ,01 natural sciences ,nitrogen ,Climate change feedback ,THERMAL STATE ,CARBON STORAGE ,greenhouse gases ,STOCKS ,0105 earth and related environmental sciences ,Multidisciplinary ,AVAILABILITY ,04 agricultural and veterinary sciences ,15. Life on land ,equipment and supplies ,Subarctic climate ,Tundra ,Arctic geoengineering ,Arctic soils ,SOIL ,climate change ,Arctic ,13. Climate action ,Physical Sciences ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,Environmental science ,Permafrost carbon cycle - Abstract
Permafrost in the Arctic is thawing, exposing large carbon and nitrogen stocks for decomposition. Gaseous carbon release from Arctic soils due to permafrost thawing is known to be substantial, but growing evidence suggests that Arctic soils may also be relevant sources of nitrous oxide (N2O). Here we show that N2O emissions from subarctic peatlands increase as the permafrost thaws. In our study, the highest postthaw emissions occurred from bare peat surfaces, a typical landform in permafrost peatlands, where permafrost thaw caused a fivefold increase in emissions (0.56 ± 0.11 vs. 2.81 ± 0.6 mg N2O m−2 d−1). These emission rates match those from tropical forest soils, the world’s largest natural terrestrial N2O source. The presence of vegetation, known to limit N2O emissions in tundra, did decrease (by ∼90%) but did not prevent thaw-induced N2O release, whereas waterlogged conditions suppressed the emissions. We show that regions with high probability for N2O emissions cover one-fourth of the Arctic. Our results imply that the Arctic N2O budget will depend strongly on moisture changes, and that a gradual deepening of the active layer will create a strong noncarbon climate change feedback., published version, peerReviewed
- Published
- 2017
18. Assessing the spatial variability in peak season CO2 exchange characteristics across the Arctic tundra using a light response curve parameterization
- Author
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Adrian V. Rocha, Daniel P. Rasse, Herbert N. Mbufong, Elyn Humphreys, Torsten Sachs, Mika Aurela, Magnus Lund, Werner Eugster, Thomas Friborg, Marcin Jackowicz-Korczynski, Mikkel P. Tamstorf, Lars Kutzbach, Birger Ulf Hansen, Frans-Jan W. Parmentier, Torben R. Christensen, Walter C. Oechel, Peter M. Lafleur, and M. K. van der Molen
- Subjects
0106 biological sciences ,010504 meteorology & atmospheric sciences ,Eddy covariance ,Irradiance ,Flux ,15. Life on land ,010603 evolutionary biology ,01 natural sciences ,Tundra ,Compensation point ,13. Climate action ,Photosynthetically active radiation ,Climatology ,Environmental science ,Spatial variability ,Leaf area index ,Ecology, Evolution, Behavior and Systematics ,0105 earth and related environmental sciences ,Earth-Surface Processes - Abstract
This paper aims to assess the spatial variability in the response of CO2 exchange to irradiance across the Arctic tundra during peak season using light response curve (LRC) parameters. This investigation allows us to better understand the future response of Arctic tundra under climatic change. Peak season data were collected during different years (between 1998 and 2010) using the micrometeorological eddy covariance technique from 12 circumpolar Arctic tundra sites, in the range of 64–74° N. The LRCs were generated for 14 days with peak net ecosystem exchange (NEE) using an NEE–irradiance model. Parameters from LRCs represent site-specific traits and characteristics describing the following: (a) NEE at light saturation (Fcsat), (b) dark respiration (Rd), (c) light use efficiency (α), (d) NEE when light is at 1000 μmol m−2 s−1 (Fc1000), (e) potential photosynthesis at light saturation (Psat) and (f) the light compensation point (LCP). Parameterization of LRCs was successful in predicting CO2 flux dynamics across the Arctic tundra. We did not find any trends in LRC parameters across the whole Arctic tundra but there were indications for temperature and latitudinal differences within sub-regions like Russia and Greenland. Together, leaf area index (LAI) and July temperature had a high explanatory power of the variance in assimilation parameters (Fcsat, Fc1000 and Psat, thus illustrating the potential for upscaling CO2 exchange for the whole Arctic tundra. Dark respiration was more variable and less correlated to environmental drivers than were assimilation parameters. This indicates the inherent need to include other parameters such as nutrient availability, substrate quantity and quality in flux monitoring activities.
- Published
- 2014
19. A satellite data driven biophysical modeling approach for estimating northern peatland and tundra CO2 and CH4 fluxes
- Author
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Torsten Sachs, Torbern Tagesson, Mika Aurela, Marcin Jackowicz-Korczynski, Jennifer D. Watts, Janne Rinne, Walter C. Oechel, Donatella Zona, Frans-Jan W. Parmentier, and John S. Kimball
- Subjects
Peat ,010504 meteorology & atmospheric sciences ,Eddy covariance ,04 agricultural and veterinary sciences ,Vegetation ,15. Life on land ,01 natural sciences ,Tundra ,chemistry.chemical_compound ,chemistry ,Arctic ,13. Climate action ,Climatology ,Carbon dioxide ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,Environmental science ,Ecosystem ,Ecosystem respiration ,Ecology, Evolution, Behavior and Systematics ,0105 earth and related environmental sciences ,Earth-Surface Processes - Abstract
The northern terrestrial net ecosystem carbon balance (NECB) is contingent on inputs from vegetation gross primary productivity (GPP) to offset the ecosystem respiration (Reco) of carbon dioxide (CO2) and methane (CH4) emissions, but an effective framework to monitor the regional Arctic NECB is lacking. We modified a terrestrial carbon flux (TCF) model developed for satellite remote sensing applications to evaluate wetland CO2 and CH4 fluxes over pan-Arctic eddy covariance (EC) flux tower sites. The TCF model estimates GPP, CO2 and CH4 emissions using in situ or remote sensing and reanalysis-based climate data as inputs. The TCF model simulations using in situ data explained > 70% of the r2 variability in the 8 day cumulative EC measured fluxes. Model simulations using coarser satellite (MODIS) and reanalysis (MERRA) records accounted for approximately 69% and 75% of the respective r2 variability in the tower CO2 and CH4 records, with corresponding RMSE uncertainties of ≤ 1.3 g C m−2 d−1 (CO2) and 18.2 mg C m−2 d−1 (CH4). Although the estimated annual CH4 emissions were small (< 18 g C m−2 yr−1) relative to Reco (> 180 g C m−2 yr−1), they reduced the across-site NECB by 23% and contributed to a global warming potential of approximately 165 ± 128 g CO2eq m−2 yr−1 when considered over a 100 year time span. This model evaluation indicates a strong potential for using the TCF model approach to document landscape-scale variability in CO2 and CH4 fluxes, and to estimate the NECB for northern peatland and tundra ecosystems.
- Published
- 2014
20. BVOC ecosystem flux measurements at a high latitude wetland site
- Author
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Anna Ekberg, Marcin Jackowicz-Korczynski, Kristina Bäckstrand, Sean Hayward, Almut Arneth, Mikhail Mastepanov, Patrik M. Crill, Thomas Holst, and Thomas Friborg
- Subjects
Atmospheric Science ,biology ,Humidity ,Growing season ,Vegetation ,Sensible heat ,Eriophorum ,biology.organism_classification ,Atmospheric sciences ,Sphagnum ,lcsh:QC1-999 ,Latitude ,lcsh:Chemistry ,Atmosphere ,lcsh:QD1-999 ,Climatology ,Environmental science ,lcsh:Physics - Abstract
In this study, we present summertime concentrationsand fluxes of biogenic volatile organic compounds(BVOCs) measured at a sub-arctic wetland in northern Swedenusing a disjunct eddy-covariance (DEC) technique basedon a proton transfer reaction mass spectrometer (PTR-MS).The vegetation at the site was dominated by Sphagnum,Carex and Eriophorum spp. The measurements reportedhere cover a period of 50 days (1 August to 19 September2006), approximately one half of the growing season at thesite, and allowed to investigate the effect of day-to-day variationin weather as well as of vegetation senescence on dailyBVOC fluxes, and on their temperature and light responses.The sensitivity drift of the DEC system was assessed bycomparing H3O+-ion cluster formed with water molecules(H3O+(H2O) at m37) with water vapour concentration measurementsmade using an adjacent humidity sensor, and theapplicability of the DEC method was analysed by a comparisonof sensible heat fluxes for high frequency and DEC dataobtained from the sonic anemometer. These analyses showedno significant PTR-MS sensor drift over a period of severalweeks and only a small flux-loss due to high-frequency spectrumomissions. This loss was within the range expectedfrom other studies and the theoretical considerations. In this study, we present summertime concentrations and fluxes of biogenic volatile organic compounds (BVOCs) measured at a sub-arctic wetland in northern Sweden using a disjunct eddy-covariance (DEC) technique based on a proton transfer reaction mass spectrometer (PTR-MS). The vegetation at the site was dominated by Sphagnum, Carex and \textit{Eriophorum} spp. The measurements reported here cover a period of 50 days (1 August to 19 September 2006), approximately one half of the growing season at the site, and allowed to investigate the effect of day-to-day variation in weather as well as of vegetation senescence on daily BVOC fluxes, and on their temperature and light responses. The sensitivity drift of the DEC system was assessed by comparing H3O+-ion cluster formed with water molecules (H3O+(H2O) at m37) with water vapour concentration measurements made using an adjacent humidity sensor, and the applicability of the DEC method was analysed by a comparison of sensible heat fluxes for high frequency and DEC data obtained from the sonic anemometer. These analyses showed no significant PTR-MS sensor drift over a period of several weeks and only a small flux-loss due to high-frequency spectrum omissions. This loss was within the range expected from other studies and the theoretical considerations.Standardised (20 °C and 1000 μmol m−2 s−1 PAR) summer isoprene emission rates found in this study of 329 μg C m−2 (ground area) h−1 were comparable with findings from more southern boreal forests, and fen-like ecosystems. On a diel scale, measured fluxes indicated a stronger temperature dependence than emissions from temperate or (sub)tropical ecosystems. For the first time, to our knowledge, we report ecosystem methanol fluxes from a sub-arctic ecosystem. Maximum daytime emission fluxes were around 270 μg m−2 h−1 (ca. 100 μg C m−2 h−1), and during most nights small negative fluxes directed from the atmosphere to the surface were observed.
- Published
- 2010
21. Modelling CH4 emissions from arctic wetlands: effects of hydrological parameterization
- Author
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Kristina Bäckstrand, Marcin Jackowicz-Korczynski, Trofim C. Maximov, Patric M. Crill, Alla Yurova, Torben R. Christensen, A.M.R. Petrescu, and J. van Huissteden
- Subjects
Hydrology ,geography ,geography.geographical_feature_category ,Water table ,Growing season ,Wetland ,Hydrology (agriculture) ,Arctic ,Mire ,Vegetation type ,Environmental science ,Precipitation ,Ecology, Evolution, Behavior and Systematics ,Earth-Surface Processes - Abstract
This study compares the CH4 fluxes from two arctic wetland sites of different annual temperatures during 2004 to 2006. The PEATLAND-VU model was used to simulate the emissions. The CH4 module of PEATLAND-VU is based on the Walter-Heimann model. The first site is located in northeast Siberia, Indigirka lowlands, Kytalyk reserve (70 degrees N, 147 degrees E) in a continuous permafrost region with mean annual temperatures of -14.3 degrees C. The other site is Stordalen mire in the eastern part of Lake Tornetrask (68 degrees N, 19 degrees E) ten kilometres east of Abisko, northern Sweden. It is located in a discontinuous permafrost region. Stordalen has a sub arctic climate with a mean annual temperature of -0.7 degrees C. Model input consisted of observed temperature, precipitation and snow cover data. In all cases, modelled CH4 emissions show a direct correlation between variations in water table and soil temperature variations. The differences in CH4 emissions between the two sites are caused by different climate, hydrology, soil physical properties, vegetation type and NPP. For Kytalyk the simulated CH4 fluxes show similar trends during the growing season, having average values for 2004 to 2006 between 1.29-2.09 mg CH4 m(-2) hr(-1). At Stordalen the simulated fluxes show a slightly lower average value for the same years (3.52 mg CH4 m(-2) hr(-1)) than the observed 4.7 mg CH4 m(-2) hr(-1). The effect of the longer growing season at Stordalen is simulated correctly. Our study shows that modelling of arctic CH4 fluxes is improved by adding a relatively simple hydrological model that simulates the water table position from generic weather data. Our results support the generalization in literature that CH4 fluxes in northern wetland are regulated more tightly by water table than temperature. Furthermore, parameter uncertainty at site level in wetland CH4 process models is an important factor in large scale modelling of CH4 fluxes.
- Published
- 2008
22. The uncertain climate footprint of wetlands under human pressure
- Author
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Elyn Humphreys, Mika Aurela, Carsten Grüning, Frans-Jan W. Parmentier, A. J. Dolman, Mikhail Mastepanov, Janne Rinne, Pertti J. Martikainen, Andrej Varlagin, Lawrence B. Flanagan, Marcin Jackowicz-Korczynski, Donatella Zona, Arjan Hensen, Timo Vesala, Ute Skiba, Derrick Y.F. Lai, Ana Meijide, Torsten Sachs, Dennis D. Baldocchi, Annalea Lohila, Gerard Kiely, Nigel T. Roulet, Jaclyn Hatala Matthes, Christian Bernhofer, A.M.R. Petrescu, Walter C. Oechel, Lutz Merbold, Shashi B. Verma, Elmar Veenendaal, Magnus Lund, A.P. Schrier-Uijl, Ankur R. Desai, Jacobus van Huissteden, Narasinha J. Shurpali, Matteo Sottocornola, Alessandro Cescatti, Mikkel P. Tamstorf, Torben R. Christensen, Barbara Marcolla, Thomas Friborg, Tuomas Laurila, Juha-Pekka Tuovinen, Thomas Grünwald, Chiara A. R. Corradi, Water and Climate Risk, Earth and Climate, Hydrology and Geo-environmental sciences, and Amsterdam Global Change Institute
- Subjects
Peat ,Climate ,Nitrous Oxide ,Wetland ,Carbon sequestration ,Theoretical ,Models ,SDG 13 - Climate Action ,Human Activities ,wetland conversion ,Multidisciplinary ,geography.geographical_feature_category ,Ecology ,Geography ,methane ,Temperature ,Uncertainty ,dynamics ,Plants ,PE&RC ,fluxes ,Plant Production Systems ,Physical Sciences ,Plantenecologie en Natuurbeheer ,Wetland conversion ,Climate footprint ,Methane ,drainage ,Life on Land ,methane emissions ,Climate Change ,Radiative forcing ,Land management ,Climate change ,Plant Ecology and Nature Conservation ,carbon-dioxide ,Settore BIO/07 - ECOLOGIA ,Humans ,Ecosystem ,peatlands ,ecosystem ,geography ,radiative forcing ,cycle ,variability ,carbon dioxide ,balance ,15. Life on land ,Carbon Dioxide ,Models, Theoretical ,Climate Action ,13. Climate action ,Plantaardige Productiesystemen ,Wetlands ,Environmental science ,Water resource management - Abstract
Significant climate risks are associated with a positive carbon-temperature feedback in northern latitude carbon-rich ecosystems, making an accurate analysis of human impacts on the net greenhouse gas balance of wetlands a priority. Here, we provide a coherent assessment of the climate footprint of a network of wetland sites based on simultaneous and quasi-continuous ecosystem observations of CO2 and CH4 fluxes. Experimental areas are located both in natural and in managed wetlands and cover a wide range of climatic regions, ecosystem types, and management practices. Based on direct observations we predict that sustained CH4 emissions in natural ecosystems are in the long term (i.e., several centuries) typically offset by CO2 uptake, although with large spatiotemporal variability. Using a space-for-time analogy across ecological and climatic gradients, we represent the chronosequence from natural to managed conditions to quantify the "cost" of CH4 emissions for the benefit of net carbon sequestration. With a sustained pulse-response radiative forcing model, we found a significant increase in atmospheric forcing due to land management, in particular for wetland converted to cropland. Our results quantify the role of human activities on the climate footprint of northern wetlands and call for development of active mitigation strategies for managed wetlands and new guidelines of the Intergovernmental Panel on Climate Change (IPCC) accounting for both sustained CH4 emissions and cumulative CO2 exchange.
- Published
- 2015
23. Carbon budget estimation of a subarctic catchment using adynamic ecosystem model at high spatial resolution
- Author
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Terry V. Callaghan, Andreas Persson, David Olefeldt, Torben R. Christensen, Michal Heliasz, Marcin Jackowicz-Korczynski, Paul A. Miller, Jing Tang, Benjamin Smith, Zhenlin Yang, Petter Pilesjö, and Томский государственный университет Институт биологии, экологии, почвоведения, сельского и лесного хозяйства (Биологический институт) Кафедра ботаники
- Subjects
lcsh:Life ,chemistry.chemical_element ,Atmospheric sciences ,GLOBAL VEGETATION MODEL ,Carbon cycle ,NORTHERN SWEDEN ,Ecosystem model ,lcsh:QH540-549.5 ,Ecosystem ,ATMOSPHERIC CO2 ,TERRESTRIAL BIOSPHERE ,Ecology, Evolution, Behavior and Systematics ,Earth-Surface Processes ,BIRCH FOREST ,углерод ,GAS BUDGET ,Aquatic ecosystem ,lcsh:QE1-996.5 ,Global warming ,Carbon sink ,CLIMATIC CHANGES ,Subarctic climate ,TUNDRA ,lcsh:Geology ,lcsh:QH501-531 ,экосистемы ,chemistry ,THAWING PERMAFROST ,BALANCE ,Climatology ,Environmental science ,Субарктика ,lcsh:Ecology ,Carbon - Abstract
Large amount of organic carbon is stored in high latitude soils. A substantial proportion of this carbon stock is vulnerable and may decompose rapidly due to temperature increases that are already greater than the global average. It is therefore crucial to quantify and understand carbon exchange between the atmosphere and subarctic/arctic ecosystems. In this paper, we combine an arctic-enabled version of the process-based dynamic ecosystem model, LPJ-GUESS (version LPJG-WHyMe-TFM) with comprehensive observations of terrestrial and aquatic carbon fluxes to simulate long-term carbon exchange in a subarctic catchment comprising both mineral and peatland soils. The model is applied at 50 m resolution and is shown to be able to capture the seasonality and magnitudes of observed fluxes at this fine scale. The modelled magnitudes of CO2 uptake generally follow the descending sequence: birch forest, non-permafrost Eriophorum, Sphagnum and then tundra heath during the observation periods. The catchment-level carbon fluxes from aquatic systems are dominated by CO2 emissions from streams. Integrated across the whole catchment, we estimate that the area is a carbon sink at present, and will become an even stronger carbon sink by 2080, which is mainly a result of a projected densification of birch forest and its encroachment into tundra heath. However, the magnitudes of the modelled sinks are very dependent on future atmospheric CO2 concentrations. Furthermore, comparisons of global warming potentials between two simulations with and without CO2 increase since 1960 reveal that the increased methane emission from the peatland could double the warming effects of the whole catchment by 2080 in the absence of CO2 fertilization of the vegetation. This is the first process-based model study of the temporal evolution of a catchment-level carbon budget at high spatial resolution, integrating comprehensive and diverse fluxes including both terrestrial and aquatic carbon. Though this study also highlights some limitations in modelling subarctic ecosystem responses to climate change including aquatic system flux dynamics, nutrient limitation, herbivory and other disturbances and peatland expansion, our application provides a mechanism to resolve the complexity of carbon cycling in subarctic ecosystems while simultaneously pointing out the key model developments for capturing complex subarctic processes.
- Published
- 2015
24. Monitoring the multi-year carbon balance of a subarctic palsa mire with micrometeorological techniques
- Author
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Thomas Friborg, Mika Aurela, Marcin Jackowicz-Korczynski, Patrick M. Crill, Torben R. Christensen, Mikhail Mastepanov, and Michal Heliasz
- Subjects
Sweden ,Time Factors ,Ecology ,Minerotrophic ,Arctic Regions ,Geography, Planning and Development ,Eddy covariance ,Temperature ,Carbon sink ,General Medicine ,Permafrost ,Atmospheric sciences ,Subarctic climate ,Article ,Carbon cycle ,Carbon Cycle ,Mire ,Climatology ,Environmental Chemistry ,Environmental science ,Palsa ,Seasons ,Weather ,Ecosystem ,Environmental Monitoring - Abstract
This article reports a dataset on 8 years of monitoring carbon fluxes in a subarctic palsa mire based on micrometeorological eddy covariance measurements. The mire is a complex with wet minerotrophic areas and elevated dry palsa as well as intermediate sub-ecosystems. The measurements document primarily the emission originating from the wet parts of the mire dominated by a rather homogenous cover of Eriophorum angustifolium. The CO(2)/CH(4) flux measurements performed during the years 2001-2008 showed that the areas represented in the measurements were a relatively stable sink of carbon with an average annual rate of uptake amounting to on average -46 g C m(-2) y(-1) including an equally stable loss through CH(4) emissions (18-22 g CH(4)-C m(-2) y(-1)). This consistent carbon sink combined with substantial CH(4) emissions is most likely what is to be expected as the permafrost under palsa mires degrades in response to climate warming.
- Published
- 2012
25. Quantifying the relative importance of lake emissions in the carbon budget of a subarctic catchment
- Author
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Jan Karlsson, Torben R. Christensen, Charlotte L. Roehm, Marcin Jackowicz-Korczynski, Johannes Förster, Patrick M. Crill, Peter Rosén, Ulla Kokfelt, and Dan Hammarlund
- Subjects
Atmospheric Science ,Ecology ,Terrestrial biological carbon cycle ,Atmospheric carbon cycle ,Paleontology ,Soil Science ,Carbon sink ,Forestry ,Soil science ,Soil carbon ,Aquatic Science ,Oceanography ,Atmospheric sciences ,Permafrost ,Geophysics ,Space and Planetary Science ,Geochemistry and Petrology ,Greenhouse gas ,parasitic diseases ,Dissolved organic carbon ,Earth and Planetary Sciences (miscellaneous) ,Environmental science ,Permafrost carbon cycle ,Earth-Surface Processes ,Water Science and Technology - Abstract
Climate change and thawing of permafrost will likely result in increased decomposition of terrestrial organic carbon and subsequent carbon emissions to the atmosphere from terrestrial and aquatic systems. The quantitative importance of mineralization of terrestrial organic carbon in lakes in relation to terrestrial carbon fluxes is poorly understood and a serious drawback for the understanding of carbon budgets. We studied a subarctic lake in an area of discontinuous permafrost to assess the quantitative importance of lake carbon emission for the catchment carbon balance. Estimates of net ecosystem production and stable carbon-isotope composition of dissolved organic carbon in the lake water suggest substantial input and respiration of terrestrial organic carbon in the lake. The lake was a net source of CO2 and CH4 to the atmosphere at ice breakup in spring and during the whole ice-free period. The carbon emission from the lake was similar in magnitude to the terrestrial net release of carbon to the atmosphere. The results indicate that lakes are important sources of catchment carbon emission, potentially increasing the positive feedback from permafrost thawing on global warming.
- Published
- 2010
26. Annual cycle of methane emission from a subarctic peatland
- Author
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Torben R. Christensen, Patrick M. Crill, Lena Ström, Mikhail Mastepanov, Marcin Jackowicz-Korczynski, Thomas Friborg, and Kristina Bäckstrand
- Subjects
Atmospheric Science ,Peat ,Eddy covariance ,Soil Science ,Wetland ,Aquatic Science ,Oceanography ,Permafrost ,Atmospheric sciences ,Methane ,chemistry.chemical_compound ,Geochemistry and Petrology ,Earth and Planetary Sciences (miscellaneous) ,Cryosphere ,Earth-Surface Processes ,Water Science and Technology ,geography ,geography.geographical_feature_category ,Ecology ,Paleontology ,Forestry ,Annual cycle ,Subarctic climate ,Geophysics ,chemistry ,Space and Planetary Science ,Climatology ,Environmental science - Abstract
Although much attention in recent years has been devoted to methane (CH4) emissions from northern wetlands, measurement based data sets providing full annual budgets are still limited in number. Th ...
- Published
- 2010
27. Annual carbon gas budget for a subarctic peatland, Northern Sweden
- Author
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Mikhail Mastepanov, Kristina Bäckstrand, Patrick M. Crill, Marcin Jackowicz-Korczynski, Torben R. Christensen, and David Bastviken
- Subjects
Peat ,biology ,lcsh:QE1-996.5 ,lcsh:Life ,Soil carbon ,Eriophorum ,Permafrost ,biology.organism_classification ,Atmospheric sciences ,Sphagnum ,Subarctic climate ,lcsh:Geology ,lcsh:QH501-531 ,lcsh:QH540-549.5 ,Mire ,Climatology ,Environmental science ,lcsh:Ecology ,Palsa ,Ecology, Evolution, Behavior and Systematics ,Earth-Surface Processes - Abstract
Temperatures in the Arctic regions are rising, thawing permafrost and exposing previously stable soil organic carbon (OC) to decomposition. This can result in northern latitude soils, which have accumulated large amounts of OC potentially shifting from atmospheric C sinks to C sources with positive feedback on climate warming. In this paper, we estimate the annual net C gas balance (NCB) of the subarctic mire Stordalen, based on automatic chamber measurements of CO2 and total hydrocarbon (THC; CH4 and NMVOCs) exchange. We studied the dominant vegetation communities with different moisture and permafrost characteristics; a dry Palsa underlain by permafrost, an intermediate thaw site with Sphagnum spp. and a wet site with Eriophorum spp. where the soil thaws completely. Whole year accumulated fluxes of CO2 were estimated to 29.7, −35.3 and −34.9 gC m−2 respectively for the Palsa, Sphagnum and Eriophorum sites (positive flux indicates an addition of C to the atmospheric pool). The corresponding annual THC emissions were 0.5, 6.2 and 31.8 gC m−2 for the same sites. Therefore, the NCB for each of the sites was 30.2, −29.1 and −3.1 gC m−2 respectively for the Palsa, Sphagnum and Eriophorum site. On average, the whole mire was a CO2 sink of 2.6 gC m−2 and a THC source of 6.4 gC m−2 over a year. Consequently, the mire was a net source of C to the atmosphere by 3.9 gC m−2 (based on area weighted estimates for each of the three plant communities). Early and late snow season efflux of CO2 and THC emphasize the importance of winter measurements for complete annual C budgets. Decadal vegetation changes at Stordalen indicate that both the productivity and the THC emissions increased between 1970 and 2000. Considering the GWP100 of CH4, the net radiative forcing on climate increased 21% over the same time. In conclusion, reduced C compounds in these environments have high importance for both the annual C balance and climate.
28. Rapid responses of permafrost and vegetation to experimentally increased snow cover in sub-arctic Sweden
- Author
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Torben R. Christensen, Margareta Johansson, Terry V. Callaghan, Julia Bosiö, H. Jonas Åkerman, and Marcin Jackowicz-Korczynski
- Subjects
0106 biological sciences ,Peat ,010504 meteorology & atmospheric sciences ,снежный покров ,Soil science ,Permafrost ,Graminoid ,010603 evolutionary biology ,01 natural sciences ,Швеция ,вечная мерзлота ,Precipitation ,0105 earth and related environmental sciences ,General Environmental Science ,Eriophorum vaginatum ,geography ,Plateau ,geography.geographical_feature_category ,biology ,Renewable Energy, Sustainability and the Environment ,Public Health, Environmental and Occupational Health ,Vegetation ,15. Life on land ,biology.organism_classification ,Snow ,13. Climate action ,Environmental science ,Субарктика ,почвы ,Physical geography - Abstract
Increased snow depth already observed, and that predicted for the future are of critical importance to many geophysical and biological processes as well as human activities. The future characteristics of sub-arctic landscapes where permafrost is particularly vulnerable will depend on complex interactions between snow cover, vegetation and permafrost. An experimental manipulation was, therefore, set up on a lowland peat plateau with permafrost, in northernmost Sweden, to simulate projected future increases in winter precipitation and to study their effects on permafrost and vegetation. After seven years of treatment, statistically significant differences between manipulated and control plots were found in mean winter ground temperatures, which were 1.5 degrees C higher in manipulated plots. During the winter, a difference in minimum temperatures of up to 9 degrees C higher could be found in individual manipulated plots compared with control plots. Active layer thicknesses increased at the manipulated plots by almost 20% compared with the control plots and a mean surface subsidence of 24 cm was recorded in the manipulated plots compared to 5 cm in the control plots. The graminoid Eriophorum vaginatum has expanded in the manipulated plots and the vegetation remained green longer in the season. (Less)
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