Articles | Volume 19, issue 7
https://doi.org/10.5194/bg-19-1959-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-19-1959-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
06 Apr 2022
Research article |
| 06 Apr 2022
| 06 Apr 2022
Peat macropore networks – new insights into episodic and hotspot methane emission
School of Forest Sciences, Faculty of Science and Forestry, University of Eastern Finland, P.O. Box 111, 80101 Joensuu, Finland
Marjo Palviainen
Department of Forest Sciences, University of Helsinki, P.O. Box 27, 00014 Helsinki, Finland
Tiia Grönholm
Finnish Meteorological Institute (FMI), Erik Palmenin aukio 1, 00560 Helsinki, Finland
Maarit Raivonen
Institute for Atmospheric and Earth System Research (INAR)/Physics, Faculty of Science, University of Helsinki, P.O. Box 68, 00014 Helsinki, Finland
Lukas Kohl
Department of Agricultural Sciences, University of Helsinki, P.O. Box 56, 00014 Helsinki, Finland
Institute for Atmospheric and Earth System Research (INAR)/Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, P.O. Box 56, 00014 Helsinki, Finland
Vincent Gauci
Birmingham Institute of Forest Research (BIFoR), University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
Iñaki Urzainki
School of Forest Sciences, Faculty of Science and Forestry, University of Eastern Finland, P.O. Box 111, 80101 Joensuu, Finland
Natural Resources Institute Finland (Luke), Latokartanonkaari 9, 00790 Helsinki, Finland
Annamari Laurén
School of Forest Sciences, Faculty of Science and Forestry, University of Eastern Finland, P.O. Box 111, 80101 Joensuu, Finland
Related authors
Lukas Kohl, Petri Kiuru, Marjo Palviainen, Maarit Raivonen, Markku Koskinen, Mari Pihlatie, and Annamari Laurén
Biogeosciences, 22, 1711–1727, https://doi.org/10.5194/bg-22-1711-2025, https://doi.org/10.5194/bg-22-1711-2025, 2025
Short summary
Short summary
We present an assay to illuminate heterogeneity in biogeochemical transformations within peat samples. For this, we injected isotope-labeled acetate into peat cores and monitored the release of label-derived gases, which we compared to microtomography images. The fraction of label converted to CO2 and the rapidness of this conversion were linked to injection depth and air-filled porosity.
Petri Kiuru, Marjo Palviainen, Arianna Marchionne, Tiia Grönholm, Maarit Raivonen, Lukas Kohl, and Annamari Laurén
Biogeosciences, 19, 5041–5058, https://doi.org/10.5194/bg-19-5041-2022, https://doi.org/10.5194/bg-19-5041-2022, 2022
Short summary
Short summary
Peatlands are large carbon stocks. Emissions of carbon dioxide and methane from peatlands may increase due to changes in management and climate. We studied the variation in the gas diffusivity of peat with depth using pore network simulations and laboratory experiments. Gas diffusivity was found to be lower in deeper peat with smaller pores and lower pore connectivity. However, gas diffusivity was not extremely low in wet conditions, which may reflect the distinctive structure of peat.
Lukas Kohl, Petri Kiuru, Marjo Palviainen, Maarit Raivonen, Markku Koskinen, Mari Pihlatie, and Annamari Laurén
Biogeosciences, 22, 1711–1727, https://doi.org/10.5194/bg-22-1711-2025, https://doi.org/10.5194/bg-22-1711-2025, 2025
Short summary
Short summary
We present an assay to illuminate heterogeneity in biogeochemical transformations within peat samples. For this, we injected isotope-labeled acetate into peat cores and monitored the release of label-derived gases, which we compared to microtomography images. The fraction of label converted to CO2 and the rapidness of this conversion were linked to injection depth and air-filled porosity.
Androniki Maragkidou, Tiia Grönholm, Laura Rautiainen, Juha Nikmo, Jukka-Pekka Jalkanen, Timo Mäkelä, Timo Anttila, Lauri Laakso, and Jaakko Kukkonen
Atmos. Chem. Phys., 25, 2443–2457, https://doi.org/10.5194/acp-25-2443-2025, https://doi.org/10.5194/acp-25-2443-2025, 2025
Short summary
Short summary
The Baltic Sea's designation as a sulfur emission control area in 2006, with subsequent regulations, significantly reduced sulfur emissions from shipping. Our study analysed air quality data from 2003 to 2020 on the island Utö and employed modelling, showing a continuous decrease in SO2 concentrations since 2003 and thus evidencing the effectiveness of such regulations in improving air quality. It also underscored the importance of long-term, high-resolution monitoring at remote marine sites.
Maria K. Tenkanen, Aki Tsuruta, Hugo Denier van der Gon, Lena Höglund-Isaksson, Antti Leppänen, Tiina Markkanen, Ana Maria Roxana Petrescu, Maarit Raivonen, Hermanni Aaltonen, and Tuula Aalto
Atmos. Chem. Phys., 25, 2181–2206, https://doi.org/10.5194/acp-25-2181-2025, https://doi.org/10.5194/acp-25-2181-2025, 2025
Short summary
Short summary
Accurate national methane (CH4) emission estimates are essential for tracking progress towards climate goals. This study compares estimates from Finland, which use different methods and scales, and shows how well a global model estimates emissions within a country. The bottom-up estimates vary a lot, but constraining them with atmospheric CH4 measurements brought the estimates closer together. We also highlight the importance of quantifying natural emissions alongside anthropogenic emissions.
Tuula Aalto, Aki Tsuruta, Jarmo Mäkelä, Jurek Müller, Maria Tenkanen, Eleanor Burke, Sarah Chadburn, Yao Gao, Vilma Mannisenaho, Thomas Kleinen, Hanna Lee, Antti Leppänen, Tiina Markkanen, Stefano Materia, Paul A. Miller, Daniele Peano, Olli Peltola, Benjamin Poulter, Maarit Raivonen, Marielle Saunois, David Wårlind, and Sönke Zaehle
Biogeosciences, 22, 323–340, https://doi.org/10.5194/bg-22-323-2025, https://doi.org/10.5194/bg-22-323-2025, 2025
Short summary
Short summary
Wetland methane responses to temperature and precipitation were studied in a boreal wetland-rich region in northern Europe using ecosystem models, atmospheric inversions, and upscaled flux observations. The ecosystem models differed in their responses to temperature and precipitation and in their seasonality. However, multi-model means, inversions, and upscaled fluxes had similar seasonality, and they suggested co-limitation by temperature and precipitation.
Vilna Tyystjärvi, Tiina Markkanen, Leif Backman, Maarit Raivonen, Antti Leppänen, Xuefei Li, Paavo Ojanen, Kari Minkkinen, Roosa Hautala, Mikko Peltoniemi, Jani Anttila, Raija Laiho, Annalea Lohila, Raisa Mäkipää, and Tuula Aalto
Biogeosciences, 21, 5745–5771, https://doi.org/10.5194/bg-21-5745-2024, https://doi.org/10.5194/bg-21-5745-2024, 2024
Short summary
Short summary
Drainage of boreal peatlands strongly influences soil methane fluxes, with important implications for climatic impacts. Here we simulate methane fluxes in forestry-drained and restored peatlands during the 21st century. We found that restoration turned peatlands into a source of methane, but the magnitude varied regionally. In forests, changes in the water table level influenced methane fluxes, and in general, the sink was weaker under rotational forestry compared to continuous cover forestry.
Mikko Heikkilä, Krista Luoma, Timo Mäkelä, and Tiia Grönholm
Atmos. Chem. Phys., 24, 8927–8941, https://doi.org/10.5194/acp-24-8927-2024, https://doi.org/10.5194/acp-24-8927-2024, 2024
Short summary
Short summary
Black carbon (BC) concentration was measured from 211 ship exhaust gas plumes at a remote marine station. Emission factors of BC were calculated in grams per kilogram of fuel. Ships with an exhaust gas cleaning system (EGCS) were found to have median BC emissions per fuel consumed 5 times lower than ships without an EGCS. However, this might be because of non-EGCS ships running at low engine loads rather than the EGCS itself. A local speed restriction would increase BC emissions of ships.
Jalisha T. Kallingal, Johan Lindström, Paul A. Miller, Janne Rinne, Maarit Raivonen, and Marko Scholze
Geosci. Model Dev., 17, 2299–2324, https://doi.org/10.5194/gmd-17-2299-2024, https://doi.org/10.5194/gmd-17-2299-2024, 2024
Short summary
Short summary
By unlocking the mysteries of CH4 emissions from wetlands, our work improved the accuracy of the LPJ-GUESS vegetation model using Bayesian statistics. Via assimilation of long-term real data from a wetland, we significantly enhanced CH4 emission predictions. This advancement helps us better understand wetland contributions to atmospheric CH4, which are crucial for addressing climate change. Our method offers a promising tool for refining global climate models and guiding conservation efforts
Iñaki Urzainki, Marjo Palviainen, Hannu Hökkä, Sebastian Persch, Jeffrey Chatellier, Ophelia Wang, Prasetya Mahardhitama, Rizaldy Yudhista, and Annamari Laurén
Biogeosciences, 20, 2099–2116, https://doi.org/10.5194/bg-20-2099-2023, https://doi.org/10.5194/bg-20-2099-2023, 2023
Short summary
Short summary
Drained peatlands (peat areas where ditches have been excavated to enhance crop productivity) are one of the main sources of carbon dioxide emissions globally. Blocking the ditches by building dams is a common strategy to raise the water table and to mitigate carbon dioxide emissions. But how effective is ditch blocking in raising the overall water table over a large area? Our work tackles this question by making use of the available data and physics-based hydrological modeling.
Ana Maria Roxana Petrescu, Chunjing Qiu, Matthew J. McGrath, Philippe Peylin, Glen P. Peters, Philippe Ciais, Rona L. Thompson, Aki Tsuruta, Dominik Brunner, Matthias Kuhnert, Bradley Matthews, Paul I. Palmer, Oksana Tarasova, Pierre Regnier, Ronny Lauerwald, David Bastviken, Lena Höglund-Isaksson, Wilfried Winiwarter, Giuseppe Etiope, Tuula Aalto, Gianpaolo Balsamo, Vladislav Bastrikov, Antoine Berchet, Patrick Brockmann, Giancarlo Ciotoli, Giulia Conchedda, Monica Crippa, Frank Dentener, Christine D. Groot Zwaaftink, Diego Guizzardi, Dirk Günther, Jean-Matthieu Haussaire, Sander Houweling, Greet Janssens-Maenhout, Massaer Kouyate, Adrian Leip, Antti Leppänen, Emanuele Lugato, Manon Maisonnier, Alistair J. Manning, Tiina Markkanen, Joe McNorton, Marilena Muntean, Gabriel D. Oreggioni, Prabir K. Patra, Lucia Perugini, Isabelle Pison, Maarit T. Raivonen, Marielle Saunois, Arjo J. Segers, Pete Smith, Efisio Solazzo, Hanqin Tian, Francesco N. Tubiello, Timo Vesala, Guido R. van der Werf, Chris Wilson, and Sönke Zaehle
Earth Syst. Sci. Data, 15, 1197–1268, https://doi.org/10.5194/essd-15-1197-2023, https://doi.org/10.5194/essd-15-1197-2023, 2023
Short summary
Short summary
This study updates the state-of-the-art scientific overview of CH4 and N2O emissions in the EU27 and UK in Petrescu et al. (2021a). Yearly updates are needed to improve the different respective approaches and to inform on the development of formal verification systems. It integrates the most recent emission inventories, process-based model and regional/global inversions, comparing them with UNFCCC national GHG inventories, in support to policy to facilitate real-time verification procedures.
Yao Gao, Eleanor J. Burke, Sarah E. Chadburn, Maarit Raivonen, Mika Aurela, Lawrence B. Flanagan, Krzysztof Fortuniak, Elyn Humphreys, Annalea Lohila, Tingting Li, Tiina Markkanen, Olli Nevalainen, Mats B. Nilsson, Włodzimierz Pawlak, Aki Tsuruta, Huiyi Yang, and Tuula Aalto
Biogeosciences Discuss., https://doi.org/10.5194/bg-2022-229, https://doi.org/10.5194/bg-2022-229, 2022
Manuscript not accepted for further review
Short summary
Short summary
We coupled a process-based peatland CH4 emission model HIMMELI with a state-of-art land surface model JULES. The performance of the coupled model was evaluated at six northern wetland sites. The coupled model is considered to be more appropriate in simulating wetland CH4 emission. In order to improve the simulated CH4 emission, the model requires better representation of the peat soil carbon and hydrologic processes in JULES and the methane production and transportation processes in HIMMELI.
Petri Kiuru, Marjo Palviainen, Arianna Marchionne, Tiia Grönholm, Maarit Raivonen, Lukas Kohl, and Annamari Laurén
Biogeosciences, 19, 5041–5058, https://doi.org/10.5194/bg-19-5041-2022, https://doi.org/10.5194/bg-19-5041-2022, 2022
Short summary
Short summary
Peatlands are large carbon stocks. Emissions of carbon dioxide and methane from peatlands may increase due to changes in management and climate. We studied the variation in the gas diffusivity of peat with depth using pore network simulations and laboratory experiments. Gas diffusivity was found to be lower in deeper peat with smaller pores and lower pore connectivity. However, gas diffusivity was not extremely low in wet conditions, which may reflect the distinctive structure of peat.
Matthias Karl, Liisa Pirjola, Tiia Grönholm, Mona Kurppa, Srinivasan Anand, Xiaole Zhang, Andreas Held, Rolf Sander, Miikka Dal Maso, David Topping, Shuai Jiang, Leena Kangas, and Jaakko Kukkonen
Geosci. Model Dev., 15, 3969–4026, https://doi.org/10.5194/gmd-15-3969-2022, https://doi.org/10.5194/gmd-15-3969-2022, 2022
Short summary
Short summary
The community aerosol dynamics model MAFOR includes several advanced features: coupling with an up-to-date chemistry mechanism for volatile organic compounds, a revised Brownian coagulation kernel that takes into account the fractal geometry of soot particles, a multitude of nucleation parameterizations, size-resolved partitioning of semi-volatile inorganics, and a hybrid method for the formation of secondary organic aerosols within the framework of condensation and evaporation.
Ranjeet S. Sokhi, Nicolas Moussiopoulos, Alexander Baklanov, John Bartzis, Isabelle Coll, Sandro Finardi, Rainer Friedrich, Camilla Geels, Tiia Grönholm, Tomas Halenka, Matthias Ketzel, Androniki Maragkidou, Volker Matthias, Jana Moldanova, Leonidas Ntziachristos, Klaus Schäfer, Peter Suppan, George Tsegas, Greg Carmichael, Vicente Franco, Steve Hanna, Jukka-Pekka Jalkanen, Guus J. M. Velders, and Jaakko Kukkonen
Atmos. Chem. Phys., 22, 4615–4703, https://doi.org/10.5194/acp-22-4615-2022, https://doi.org/10.5194/acp-22-4615-2022, 2022
Short summary
Short summary
This review of air quality research focuses on developments over the past decade. The article considers current and future challenges that are important from air quality research and policy perspectives and highlights emerging prominent gaps of knowledge. The review also examines how air pollution management needs to adapt to new challenges and makes recommendations to guide the direction for future air quality research within the wider community and to provide support for policy.
Shahzad Gani, Lukas Kohl, Rima Baalbaki, Federico Bianchi, Taina M. Ruuskanen, Olli-Pekka Siira, Pauli Paasonen, and Hanna Vehkamäki
Geosci. Commun., 4, 507–516, https://doi.org/10.5194/gc-4-507-2021, https://doi.org/10.5194/gc-4-507-2021, 2021
Short summary
Short summary
In this article, we present authorship guidelines which also include a novel authorship form along with the documentation of the formulation process for a multidisciplinary and interdisciplinary center with more than 250 researchers. Our practical approach promotes fair authorship practices and, by focusing on clear, transparent, and timely communication, helps avoid late-stage authorship conflict.
Cited articles
Abdalla, M., Hastings, A., Truu, J., Espenberg, M., Mander, Ü., and Smith,
P.: Emissions of methane from northern peatlands: a review of management
impacts and implications for future management options, Ecol. Evol., 6,
7080–7102, https://doi.org/10.1002/ece3.2469, 2016. a, b
Asmala, E., Carstensen, J., and Räike, A.: Multiple anthropogenic drivers
behind upward trends in organic carbon concentrations in boreal rivers,
Environ. Res. Lett., 14, 124018, https://doi.org/10.1088/1748-9326/ab4fa9, 2019. a
Bachmann, J. and van der Ploeg, R. R.: A review on recent developments in soil
water retention theory: interfacial tension and temperature effects, J. Plant
Nutr. Soil Sc., 165, 468–478,
https://doi.org/10.1002/1522-2624(200208)165:4<468::AID-JPLN468>3.0.CO;2-G, 2002. a
Ball, B. C. and Smith, K. A.: Gas movement and air-filled porosity, in: Soil
and Environmental Analysis: Physical Methods, edited by: Smith, K. A. and
Mullins, C. E., 499–538, Marcel Dekker, New York, NY, 2001. a
Barthélemy, M.: Spatial networks, Phys. Rep., 499, 1–101,
https://doi.org/10.1016/j.physrep.2010.11.002, 2011. a
Beckwith, C. W., Baird, A. J., and Heathwaite, A. L.: Anisotropy and
depth-related heterogeneity of hydraulic conductivity in a bog peat. I:
laboratory measurements, Hydrol. Process., 17, 89–101,
https://doi.org/10.1002/hyp.1116, 2003. a
Beven, K. and Germann, P.: Macropores and water flow in soils, Water Resour.
Res., 18, 1311–1325, https://doi.org/10.1029/WR018i005p01311, 1982. a
Bhuiyan, R., Minkkinen, K., Helmisaari, H.-S., Ojanen, P., Penttilä, T.,
and Laiho, R.: Estimating fine-root production by tree species and
understorey functional groups in two contrasting peatland forests, Plant
Soil, 412, 299–316, https://doi.org/10.1007/s11104-016-3070-3, 2017. a
Blunt, M. J., Bijeljic, B., Dong, H., Gharbi, O., Iglauer, S., Mostaghimi, P.,
Paluszny, A., and Pentland, C.: Pore-scale imaging and modelling, Adv. Water
Resour., 51, 197–216, https://doi.org/10.1016/j.advwatres.2012.03.003, 2013. a
Clennell, M. B.: Tortuosity: a guide through the maze, Geol. Soc. Lond. Spec.
Publ., 122, 299–344, https://doi.org/10.1144/GSL.SP.1997.122.01.18, 1997. a, b
Deppe, M., Knorr, K.-H., McKnight, D. M., and Blodau, C.: Effects of short-term
drying and irrigation on CO2 and CH4 production and emission from
mesocosms of a northern bog and an alpine fen, Biogeochemistry, 100, 89–103,
https://doi.org/10.1007/s10533-010-9406-9, 2010. a
Estop-Aragonés, C. and Blodau, C.: Effects of experimental drying intensity
and duration on respiration and methane production recovery in fen peat
incubations, Soil Biol. Biochem., 47, 1–9,
https://doi.org/10.1016/j.soilbio.2011.12.008, 2012. a
Estop-Aragonés, C., Knorr, K.-H., and Blodau, C.: Controls on in situ
oxygen and dissolved inorganic carbon dynamics in peats of a temperate fen,
J. Geophys. Res., 117, G02002, https://doi.org/10.1029/2011JG001888, 2012. a
Estop-Aragonés, C., Knorr, K.-H., and Blodau, C.: Belowground in situ redox dynamics and methanogenesis recovery in a degraded fen during dry-wet cycles and flooding, Biogeosciences, 10, 421–436, https://doi.org/10.5194/bg-10-421-2013, 2013. a
Evans, C. D., Peacock, M., Baird, A. J., Artz, R. R. E., Burden, A., Callaghan,
N., Chapman, P. J., Cooper, H. M., Coyle, M., Craig, E., Cumming, A., Dixon,
S., Gauci, V., Grayson, R. P., Helfter, C., Heppell, C. M., Holden, J.,
Jones, D. L., Kaduk, J., Levy, P., Matthews, R., McNamara, N. P.,
Misselbrook, T., Oakley, S., Page, S. E., Rayment, M., Ridley, L. M.,
Stanley, K. M., Williamson, J. L., Worrall, F., and Morrison, R.: Overriding
water table control on managed peatland greenhouse gas emissions, Nature,
593, 548–552, https://doi.org/10.1038/s41586-021-03523-1, 2021. a
Fan, Z., Neff, J. C., Waldrop, M. P., Ballantyne, A. P., and Turetsky, M. R.:
Transport of oxygen in soil pore-water systems: implications for modeling
emissions of carbon dioxide and methane from peatlands, Biogeochemistry, 121,
455–470, https://doi.org/10.1007/s10533-014-0012-0, 2014. a
Freeman, L. C.: A set of measures of centrality based on betweenness,
Sociometry, 40, 35–41, https://doi.org/10.2307/3033543, 1977. a
Freeman, L. C.: Centrality in social networks conceptual clarification, Soc.
Networks, 1, 215–239, https://doi.org/10.1016/0378-8733(78)90021-7, 1978. a
Frolking, S., Talbot, J., Jones, M. C., Treat, C. C., Kauffman, J. B.,
Tuittila, E.-S., and Roulet, N.: Peatlands in the Earth’s 21st century
climate system, Environ. Rev., 19, 371–396, https://doi.org/10.1139/a11-014, 2011. a
Gharedaghloo, B., Price, J. S., Rezanezhad, F., and Quinton, W. L.: Evaluating
the hydraulic and transport properties of peat soil using pore network
modeling and X-ray micro computed tomography, J. Hydrol., 561, 494–508,
https://doi.org/10.1016/j.jhydrol.2018.04.007, 2018. a, b
Goodrich, J. P., Campbell, D. I., Roulet, N. T., Clearwater, M. J., and
Schipper, L. A.: Overriding control of methane flux temporal variability by
water table dynamics in a Southern Hemisphere, raised bog, J. Geophys.
Res.-Biogeosci., 120, 819–831, https://doi.org/10.1002/2014JG002844, 2015. a
Gorham, E.: Northern peatlands: role in the carbon cycle and probable responses
to climatic warming, Ecol. Appl., 1, 182–195, https://doi.org/10.2307/1941811, 1991. a
Gostick, J., Aghighi, M., Hinebaugh, J., Tranter, T., Hoeh, M. A.,
Day, H., Spellacy, B., Sharqawy, M. H., Bazylak, A., Burns, A.,
Lehnert, W., and Putz, A.: OpenPNM: A pore network modeling package,
Comput. Sci. Eng., 18, 60–74, https://doi.org/10.1109/MCSE.2016.49, 2016. a
Gostick, J. T.: Versatile and efficient pore network extraction method using
marker-based watershed segmentation, Phys. Rev. E, 96, 023307,
https://doi.org/10.1103/PhysRevE.96.023307, 2017. a, b
Gostick, J. T., Khan, Z. A., Tranter, T. G., Kok, M. D. R., Agnaou, M.,
Sadeghi, M., and Jervis, R.: PoreSpy: A Python toolkit for quantitative
analysis of porous media images, J. Open Source Softw., 4, 1296,
https://doi.org/10.21105/joss.01296, 2019. a
Hagberg, A. A., Schult, D. A., and Swart, P. J.: Exploring network structure,
dynamics, and function using NetworkX, in: Proceedings of the 7th Python
in Science Conference (SciPy2008), edited by: Varoquaux, G., Vaught, T.,
and Millman, J., Pasadena, California, 19–24 August 2008, 11–15, https://doi.org/10.25080/issn.2575-9752, 2008. a
Hagedorn, F. and Bellamy, P.: Hot spots and hot moments for greenhouse gas
emissions from soils, in: Soil Carbon in Sensitive European Ecosystems: From
Science to Land Management, edited by: Jandl, R., Rodeghiero, M., and Olsson,
M., 13–32, Wiley-Blackwell, Chichester, UK,
https://doi.org/10.1002/9781119970255.ch2, 2011. a
Hayward, P. M. and Clymo, R. S.: Profiles of water content and pore size in
Sphagnum and peat, and their relation to peat bog ecology, P. Roy. Soc. Lond.
B Bio., 215, 299–325, https://doi.org/10.1098/rspb.1982.0044, 1982. a
Helliwell, J. R., Sturrock, C. J., Grayling, K. M., Tracy, S. R., Flavel,
R. J., Young, I. M., Whalley, W. R., and Mooney, S. J.: Applications of X-ray
computed tomography for examining biophysical interactions and structural
development in soil systems: a review, Eur. J. Soil Sci., 64, 279–297,
https://doi.org/10.1111/ejss.12028, 2013. a
Holden, J.: Peatland hydrology and carbon release: why small-scale process
matters, Philos. T. R. Soc. A, 363, 2891–2913,
https://doi.org/10.1098/rsta.2005.1671, 2005. a
Hooijer, A., Page, S., Jauhiainen, J., Lee, W. A., Lu, X. X., Idris, A., and Anshari, G.: Subsidence and carbon loss in drained tropical peatlands, Biogeosciences, 9, 1053–1071, https://doi.org/10.5194/bg-9-1053-2012, 2012. a
Iassonov, P., Gebrenegus, T., and Tuller, M.: Segmentation of X-ray computed
tomography images of porous materials: A crucial step for characterization
and quantitative analysis of pore structures, Water Resour. Res., 45,
W09415, https://doi.org/10.1029/2009WR008087, 2009. a
Kang, H., Kwon, M. J., Kim, S., Lee, S., Jones, T. G., Johncock, A. C.,
Haraguchi, A., and Freeman, C.: Biologically driven DOC release from
peatlands during recovery from acidification, Nat. Commun., 9, 3807,
https://doi.org/10.1038/s41467-018-06259-1, 2018. a
Kettunen, A., Kaitala, V., Alm, J., Silvola, J., Nykänen, H., and
Martikainen, P. J.: Cross-correlation analysis of the dynamics of methane
emissions from a boreal peatland, Glob. Biogeochem. Cy., 10, 457–471,
https://doi.org/10.1029/96GB01609, 1996. a
Kettunen, A., Kaitala, V., Lehtinen, A., Lohila, A., Alm, J., Silvola, J., and
Martikainen, P. J.: Methane production and oxidation potentials in relation
to water table fluctuations in two boreal mires, Soil Biol. Biochem., 31,
1741–1749, https://doi.org/10.1016/S0038-0717(99)00093-0, 1999. a
Kiuru, P., Palviainen, M., and Laurén, A.: Peat macropore networks – new
insights into episodic and hotspot methane emission, Zenodo [data set],
https://doi.org/10.5281/zenodo.6327112, 2022. a
Knorr, K.-H., Oosterwoud, M. R., and Blodau, C.: Experimental drought alters
rates of soil respiration and methanogenesis but not carbon exchange in soil
of a temperate fen, Soil Biol. Biochem., 40, 1781–1791,
https://doi.org/10.1016/j.soilbio.2008.03.019, 2008. a
Knorr, K.-H., Lischeid, G., and Blodau, C.: Dynamics of redox processes in a
minerotrophic fen exposed to a water table manipulation, Geoderma, 153,
379–392, https://doi.org/10.1016/j.geoderma.2009.08.023, 2009. a
Koskinen, M., Minkkinen, K., Ojanen, P., Kämäräinen, M., Laurila, T., and Lohila, A.: Measurements of CO2 exchange with an automated chamber system throughout the year: challenges in measuring night-time respiration on porous peat soil, Biogeosciences, 11, 347–363, https://doi.org/10.5194/bg-11-347-2014, 2014. a
Kruse, J., Lennartz, B., and Leinweber, P.: A modified method for measuring
saturated hydraulic conductivity and anisotropy of fen peat samples,
Wetlands, 28, 527–531, https://doi.org/10.1672/07-153.1, 2008. a
Lai, D. Y. F.: Methane dynamics in northern peatlands: A review, Pedosphere,
19, 409–421, https://doi.org/10.1016/S1002-0160(09)00003-4, 2009. a
Laine, J. and Vasander, H.: Ecology and vegetation gradients in peatlands, in:
Peatlands in Finland, edited by: Vasander, H., 10–19, Finnish Peatland
Society, Helsinki, Finland, ISBN: 952-90-7971-0, 1996. a
Laine-Kaulio, H.: Development and analysis of dual-permeability model for
subsurface stormflow and solute transport in a forested hillslope, PhD
thesis, Department of Civil and Environmental Engineering, Aalto University
School of Engineering, Espoo, Finland, ISBN: 978-952-60-4245-9, 2011. a
Larsbo, M., Koestel, J., and Jarvis, N.: Relations between macropore network characteristics and the degree of preferential solute transport, Hydrol. Earth Syst. Sci., 18, 5255–5269, https://doi.org/10.5194/hess-18-5255-2014, 2014. a
Laurén, A.: Physical properties of the mor layer in a Scots pine stand II.
Air permeability, Can. J. Soil Sci., 77, 635–642, https://doi.org/10.4141/S95-003,
1997. a
Leifeld, J., Wüst-Galley, C., and Page, S.: Intact and managed peatland
soils as a source and sink of GHGs from 1850 to 2100, Nat. Clim. Change, 9,
945–947, https://doi.org/10.1038/s41558-019-0615-5, 2019. a
Lepilin, D., Laurén, A., Uusitalo, J., and Tuittila, E.-S.: Soil
deformation and its recovery in logging trails of drained boreal peatlands,
Can. J. Forest Res., 49, 743–751, https://doi.org/10.1139/cjfr-2018-0385, 2019. a, b
Limpens, J., Berendse, F., Blodau, C., Canadell, J. G., Freeman, C., Holden, J., Roulet, N., Rydin, H., and Schaepman-Strub, G.: Peatlands and the carbon cycle: from local processes to global implications – a synthesis, Biogeosciences, 5, 1475–1491, https://doi.org/10.5194/bg-5-1475-2008, 2008. a
Lindquist, W. B., Lee, S.-M., Coker, D. A., Jones, K. W., and Spanne, P.:
Medial axis analysis of void structure in three-dimensional tomographic
images of porous media, J. Geophys. Res., 101, 8297–8310,
https://doi.org/10.1029/95JB03039, 1996. a
Liu, H., Janssen, M., and Lennartz, B.: Changes in flow and transport patterns
in fen peat following soil degradation, Eur. J. Soil Sci., 67, 763–772,
https://doi.org/10.1111/ejss.12380, 2016. a
Liu, H., Price, J., Rezanezhad, F., and Lennartz, B.: Centennial-scale shifts
in hydrophysical properties of peat induced by drainage, Water Resour. Res.,
56, e2020WR027538, https://doi.org/10.1029/2020WR027538, 2020. a, b
McCarter, C. P. R., Rezanezhad, F., Quinton, W. L., Gharedaghloo, B., Lennartz,
B., Price, J., Connon, R., and Van Cappellen, P.: Pore-scale controls on
hydrological and geochemical processes in peat: Implications on interacting
processes, Earth-Sci. Rev., 207, 103227,
https://doi.org/10.1016/j.earscirev.2020.103227, 2020. a, b, c, d
Menberu, M. W., Tahvanainen, T., Marttila, H., Irannezhad, M., Ronkanen, A.-K.,
Penttinen, J., and Kløve, B.: Water-table-dependent hydrological changes
following peatland forestry drainage and restoration: Analysis of restoration
success, Water Resour. Res., 52, 3742–3760, https://doi.org/10.1002/2015WR018578,
2016. a
Minkkinen, K. and Laine, J.: Effect of forest drainage on the peat bulk density
of pine mires in Finland, Can. J. Forest Res., 28, 178–186,
https://doi.org/10.1139/x97-206, 1998. a, b
Newman, M. E. J.: The structure and function of complex networks, SIAM Rev.,
45, 167–256, https://doi.org/10.1137/s003614450342480, 2003. a
Otsu, N.: A threshold selection method from gray-level histograms, IEEE T.
Syst. Man Cyb., 9, 62–66, https://doi.org/10.1109/TSMC.1979.4310076, 1979. a
Päivänen, J.: Hydraulic conductivity and water retention in peat soils,
Acta For. Fenn., 129, 1–70, https://doi.org/10.14214/aff.7563, 1973. a, b
Perret, J., Prasher, S. O., Kantzas, A., and Langford, C.: Three-dimensional
quantification of macropore networks in undisturbed soil cores, Soil Sci.
Soc. Am. J., 63, 1530–1543, https://doi.org/10.2136/sssaj1999.6361530x, 1999. a, b
Pirinen, P., Simola, H., Aalto, J., Kaukoranta, J.-P., Karlsson, P., and
Ruuhela, R.: Climatological statistics of Finland 1981–2010, Reports
2012:1, Finnish Meteorological Institute, Helsinki, Finland, ISBN: 978-951-697-766-2, 2012. a
Poulovassilis, A.: Hysteresis of pore water, an application of the concept of
independent domains, Soil Sci., 93, 405–412, 1962. a
Price, J. S.: Role and character of seasonal peat soil deformation on the
hydrology of undisturbed and cutover peatlands, Water Resour. Res., 39, 1241,
https://doi.org/10.1029/2002WR001302, 2003. a
Redding, T. E. and Devito, K. J.: Particle densities of wetland soils in
northern Alberta, Canada, Can. J. Soil Sci., 86, 57–60,
https://doi.org/10.4141/S05-061, 2006. a
Reddy, K. R. and DeLaune, R. D.: Biogeochemistry of Wetlands: Science and
Applications, CRC Press, Boca Raton, Florida, ISBN: 978-1-56670-678-0, 2008. a
Rezanezhad, F., Quinton, W. L., Price, J. S., Elliot, T. R., Elrick, D., and
Shook, K. R.: Influence of pore size and geometry on peat unsaturated
hydraulic conductivity computed from 3D computed tomography image analysis,
Hydrol. Process., 24, 2983–2994, https://doi.org/10.1002/hyp.7709, 2010. a
Rezanezhad, F., Price, J. S., Quinton, W. L., Lennartz, B., Milojevic, T., and
Van Cappellen, P.: Structure of peat soils and implications for water
storage, flow and solute transport: A review update for geochemists, Chem.
Geol., 429, 75–84, https://doi.org/10.1016/j.chemgeo.2016.03.010, 2016. a, b, c
Rinne, J., Tuittila, E.-S., Peltola, O., Li, X., Raivonen, M., Alekseychik, P.,
Haapanala, S., Pihlatie, M., Aurela, M., Mammarella, I., and Vesala, T.:
Temporal variation of ecosystem scale methane emission from a boreal fen in
relation to temperature, water table position, and carbon dioxide fluxes,
Global Biogeochem. Cy., 32, 1087–1106, https://doi.org/10.1029/2017GB005747, 2018. a
Rydin, H. and Jeglum, J. K.: The Biology of Peatlands, 2nd Edn., Oxford
University Press, Oxford, UK, ISBN: 978-0-19-960299-5, 2013. a
Sarkkola, S., Hökkä, H., Koivusalo, H., Nieminen, M., Ahti, E.,
Päivänen, J., and Laine, J.: Role of tree stand evapotranspiration in
maintaining satisfactory drainage conditions in drained peatlands, Can. J.
Forest Res., 40, 1485–1496, https://doi.org/10.1139/X10-084, 2010. a
Schlegel, A.: hypothetical – Hypothesis and statistical testing in Python,
Github, https://github.com/aschleg/hypothetical (last
access: 4 March 2022), 2020. a
Seabold, S. and Perktold, J.: Statsmodels: Econometric and statistical modeling
with Python, in: Proceedings of the 9th Python in Science Conference, Austin, Texas, 28 June–3 July 2010, 92–96, https://doi.org/10.25080/Majora-92bf1922-011, 2010. a
Silins, U. and Rothwell, R. L.: Spatial patterns of aerobic limit depth and
oxygen diffusion rate at two peatlands drained for forestry in Alberta,
Can. J. Forest Res., 29, 53–61, https://doi.org/10.1139/x98-179, 1999. a
Sloan, T. J., Payne, R. J., Anderson, A. R., Gilbert, P., Mauquoy, D., Newton,
A. J., and Andersen, R.: Ground surface subsidence in an afforested peatland
fifty years after drainage and planting, Mires Peat, 23, 1–12,
https://doi.org/10.19189/MaP.2018.OMB.348, 2019. a
Stock, S. R.: Recent advances in X-ray microtomography applied to materials,
Int. Mater. Rev., 53, 129–181, https://doi.org/10.1179/174328008X277803, 2008. a
Taina, I. A., Heck, R. J., and Elliot, T. R.: Application of X-ray computed
tomography to soil science: A literature review, Can. J. Soil Sci., 88,
1–19, https://doi.org/10.4141/CJSS06027, 2008. a
Terpilowski, M.: scikit-posthocs: Pairwise multiple comparison tests in
Python, J. Open Source Softw., 4, 1169, https://doi.org/10.21105/joss.01169, 2019. a
van der Linden, J. H., Narsilio, G. A., and Tordesillas, A.: Machine learning
framework for analysis of transport through complex networks in porous,
granular media: A focus on permeability, Phys. Rev. E, 94, 022904,
https://doi.org/10.1103/PhysRevE.94.022904, 2016. a
van der Linden, J. H., Tordesillas, A., and Narsilio, G. A.: Preferential flow
pathways in a deforming granular material: self-organization into functional
groups for optimized global transport, Sci. Rep.-UK, 9, 18231,
https://doi.org/10.1038/s41598-019-54699-6, 2019.
a, b, c
van der Walt, S., Schönberger, J. L., Nunez-Iglesias, J., Boulogne, F.,
Warner, J. D., Yager, N., Gouillart, E., Yu, T., and the scikit-image
contributors: scikit-image: image processing in Python, PeerJ, 2, e453,
https://doi.org/10.7717/peerj.453, 2014. a
van Genuchten, M. T.: A closed-form equation for predicting the hydraulic
conductivity of unsaturated soils, Soil Sci. Soc. Am. J., 44, 892–898,
https://doi.org/10.2136/sssaj1980.03615995004400050002x, 1980. a
Virtanen, P., Gommers, R., Oliphant, T. E., Haberland, M., Reddy, T.,
Cournapeau, D., Burovski, E., Peterson, P., Weckesser, W., Bright, J., van
der Walt, S. J., Brett, M., Wilson, J., Millman, K. J., Mayorov, N., Nelson,
A. R. J., Jones, E., Kern, R., Larson, E., Carey, C. J., Polat, İ., Feng,
Y., Moore, E. W., VanderPlas, J., Laxalde, D., Perktold, J., Cimrman, R.,
Henriksen, I., Quintero, E. A., Harris, C. R., Archibald, A. M., Ribeiro,
A. H., Pedregosa, F., van Mulbregt, P., and SciPy 1.0 Contributors:
SciPy 1.0: fundamental algorithms for scientific computing in Python,
Nat. Methods, 17, 261–272, https://doi.org/10.1038/s41592-019-0686-2, 2020. a, b
Wachinger, G., Fiedler, S., Zepp, K., Gattinger, A., Sommer, M., and Roth, K.:
Variability of soil methane production on the micro-scale: spatial
association with hot spots of organic material and Archaeal populations, Soil
Biol. Biochem., 32, 1121–1130, https://doi.org/10.1016/S0038-0717(00)00024-9, 2000. a
Waddington, J. M., Morris, P. J., Kettridge, N., Granath, G., Thompson, D. K.,
and Moore, P. A.: Hydrological feedbacks in northern peatlands, Ecohydrology,
8, 113–127, https://doi.org/10.1002/eco.1493, 2015. a
Watts, D. J. and Strogatz, S. H.: Collective dynamics of `small-world'
networks, Nature, 393, 440–442, https://doi.org/10.1038/30918, 1998. a
Weber, T. K. D., Iden, S. C., and Durner, W.: A pore-size classification for peat bogs derived from unsaturated hydraulic properties, Hydrol. Earth Syst. Sci., 21, 6185–6200, https://doi.org/10.5194/hess-21-6185-2017, 2017. a, b, c, d
Weiss, R., Alm, J., Laiho, R., and Laine, J.: Modeling moisture retention in
peat soils, Soil Sci. Soc. Am. J., 62, 305–313,
https://doi.org/10.2136/sssaj1998.03615995006200020002x, 1998. a
Whalen, S. C.: Biogeochemistry of methane exchange between natural wetlands and
the atmosphere, Environ. Eng. Sci., 22, 73–94, https://doi.org/10.1089/ees.2005.22.73,
2005. a
Xu, X., Yuan, F., Hanson, P. J., Wullschleger, S. D., Thornton, P. E., Riley, W. J., Song, X., Graham, D. E., Song, C., and Tian, H.: Reviews and syntheses: Four decades of modeling methane cycling in terrestrial ecosystems, Biogeosciences, 13, 3735–3755, https://doi.org/10.5194/bg-13-3735-2016, 2016. a, b
Short summary
Peatlands are large sources of methane (CH4), and peat structure controls CH4 production and emissions. We used X-ray microtomography imaging, complex network theory methods, and pore network modeling to describe the properties of peat macropore networks and the role of macropores in CH4-related processes. We show that conditions for gas transport and CH4 production vary with depth and are affected by hysteresis, which may explain the hotspots and episodic spikes in peatland CH4 emissions.
Peatlands are large sources of methane (CH4), and peat structure controls CH4 production and...
Altmetrics
Final-revised paper
Preprint