Articles | Volume 8, issue 4
https://doi.org/10.5194/bg-8-963-2011
© Author(s) 2011. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/bg-8-963-2011
© Author(s) 2011. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
19 Apr 2011
Research article |
| 19 Apr 2011
Ecosystem metabolism in a temporary Mediterranean marsh (Doñana National Park, SW Spain)
O. Geertz-Hansen
Freshwater Biological Laboratory, University of Copenhagen, 51 Helsingørsgrade, 3400 Hillerød, Denmark
present address: AquaSim, Slagslunde Bygade 37, 3660 Stenløse, Denmark
C. Montes
Departamento de Ecología, Universidad Autónoma, 28049 Madrid, Spain
C. M. Duarte
UWA Oceans Institute, University of Western Australia, 35 Stirling Highway, Crawley 6009, Australia
IMEDEA (CSIC-UIB), Grupo de Oceanografía Interdisciplinar, Instituto Mediterráneo de Estudios Avanzados, C/Miquel Marqués, 21, 07190 Esporles, Illes Balears, Spain
K. Sand-Jensen
Freshwater Biological Laboratory, University of Copenhagen, 51 Helsingørsgrade, 3400 Hillerød, Denmark
N. Marbá
IMEDEA (CSIC-UIB), Grupo de Oceanografía Interdisciplinar, Instituto Mediterráneo de Estudios Avanzados, C/Miquel Marqués, 21, 07190 Esporles, Illes Balears, Spain
P. Grillas
Station Biologique de la Tour du Valat, 13200 Le Sambuc, France
Related subject area
Biogeochemistry: Wetlands
Duration of extraction determines CO2 and CH4 emissions from an actively extracted peatland in eastern Quebec, Canada
Nutrient release and flux dynamics of CO2, CH4, and N2O in a coastal peatland driven by actively induced rewetting with brackish water from the Baltic Sea
Quantification of blue carbon in salt marshes of the Pacific coast of Canada
Cutting peatland CO2 emissions with water management practices
Tracking vegetation phenology of pristine northern boreal peatlands by combining digital photography with CO2 flux and remote sensing data
Dissolved organic matter concentration and composition discontinuity at the peat–pool interface in a boreal peatland
Effects of brackish water inflow on methane-cycling microbial communities in a freshwater rewetted coastal fen
High peatland methane emissions following permafrost thaw: enhanced acetoclastic methanogenesis during early successional stages
Origin, transport, and retention of fluvial sedimentary organic matter in South Africa's largest freshwater wetland, Mkhuze Wetland System
Peat macropore networks – new insights into episodic and hotspot methane emission
Mangrove sediment organic carbon storage and sources in relation to forest age and position along a deltaic salinity gradient
Sedimentary blue carbon dynamics based on chrono-sequential observation in a tropical restored mangrove forest
Plant genotype controls wetland soil microbial functioning in response to sea-level rise
Soil greenhouse gas fluxes from tropical coastal wetlands and alternative agricultural land uses
Carbon balance of a Finnish bog: temporal variability and limiting factors based on 6 years of eddy-covariance data
High-resolution induced polarization imaging of biogeochemical carbon turnover hotspots in a peatland
Committed and projected future changes in global peatlands – continued transient model simulations since the Last Glacial Maximum
Factors controlling Carex brevicuspis leaf litter decomposition and its contribution to surface soil organic carbon pool at different water levels
Exploring constraints on a wetland methane emission ensemble (WetCHARTs) using GOSAT observations
Global peatland area and carbon dynamics from the Last Glacial Maximum to the present – a process-based model investigation
Vascular plants affect properties and decomposition of moss-dominated peat, particularly at elevated temperatures
Denitrification and associated nitrous oxide and carbon dioxide emissions from the Amazonian wetlands
Drivers of seasonal- and event-scale DOC dynamics at the outlet of mountainous peatlands revealed by high-frequency monitoring
Comparison of eddy covariance CO2 and CH4 fluxes from mined and recently rewetted sections in a northwestern German cutover bog
Microtopography is a fundamental organizing structure of vegetation and soil chemistry in black ash wetlands
Interacting effects of vegetation components and water level on methane dynamics in a boreal fen
Low methane emissions from a boreal wetland constructed on oil sand mine tailings
Evidence for preferential protein depolymerization in wetland soils in response to external nitrogen availability provided by a novel FTIR routine
Saltwater reduces potential CO2 and CH4 production in peat soils from a coastal freshwater forested wetland
Reviews and syntheses: Greenhouse gas exchange data from drained organic forest soils – a review of current approaches and recommendations for future research
Effects of sterilization techniques on chemodenitrification and N2O production in tropical peat soil microcosms
Modelling long-term blanket peatland development in eastern Scotland
Cushion bogs are stronger carbon dioxide net sinks than moss-dominated bogs as revealed by eddy covariance measurements on Tierra del Fuego, Argentina
Humic surface waters of frozen peat bogs (permafrost zone) are highly resistant to bio- and photodegradation
Multi-year methane ebullition measurements from water and bare peat surfaces of a patterned boreal bog
Sulfate deprivation triggers high methane production in a disturbed and rewetted coastal peatland
Rhizosphere to the atmosphere: contrasting methane pathways, fluxes, and geochemical drivers across the terrestrial–aquatic wetland boundary
Multi-year effect of wetting on CH4 flux at taiga–tundra boundary in northeastern Siberia deduced from stable isotope ratios of CH4
Zero to moderate methane emissions in a densely rooted, pristine Patagonian bog – biogeochemical controls as revealed from isotopic evidence
Fluvial organic carbon fluxes from oil palm plantations on tropical peatland
Reviews and syntheses: 210Pb-derived sediment and carbon accumulation rates in vegetated coastal ecosystems – setting the record straight
Response of hydrology and CO2 flux to experimentally altered rainfall frequency in a temperate poor fen, southern Ontario, Canada
Global-change effects on early-stage decomposition processes in tidal wetlands – implications from a global survey using standardized litter
Year-round simulated methane emissions from a permafrost ecosystem in Northeast Siberia
Small spatial variability in methane emission measured from a wet patterned boreal bog
Technical note: A simple approach for efficient collection of field reference data for calibrating remote sensing mapping of northern wetlands
Technical note: Comparison of methane ebullition modelling approaches used in terrestrial wetland models
Geomorphic influences on the contribution of vegetation to soil C accumulation and accretion in Spartina alterniflora marshes
Southern Hemisphere bog persists as a strong carbon sink during droughts
The effect of drought on dissolved organic carbon (DOC) release from peatland soil and vegetation sources
Laura Clark, Ian B. Strachan, Maria Strack, Nigel T. Roulet, Klaus-Holger Knorr, and Henning Teickner
Biogeosciences, 20, 737–751, https://doi.org/10.5194/bg-20-737-2023, https://doi.org/10.5194/bg-20-737-2023, 2023
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We determine the effect that duration of extraction has on CO2 and CH4 emissions from an actively extracted peatland. Peat fields had high net C emissions in the first years after opening, and these then declined to half the initial value for several decades. Findings contribute to knowledge on the atmospheric burden that results from these activities and are of use to industry in their life cycle reporting and government agencies responsible for greenhouse gas accounting and policy.
Daniel L. Pönisch, Anne Breznikar, Cordula N. Gutekunst, Gerald Jurasinski, Maren Voss, and Gregor Rehder
Biogeosciences, 20, 295–323, https://doi.org/10.5194/bg-20-295-2023, https://doi.org/10.5194/bg-20-295-2023, 2023
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Peatland rewetting is known to reduce dissolved nutrients and greenhouse gases; however, short-term nutrient leaching and high CH4 emissions shortly after rewetting are likely to occur. We investigated the rewetting of a coastal peatland with brackish water and its effects on nutrient release and greenhouse gas fluxes. Nutrient concentrations were higher in the peatland than in the adjacent bay, leading to an export. CH4 emissions did not increase, which is in contrast to freshwater rewetting.
Stephen G. Chastain, Karen E. Kohfeld, Marlow G. Pellatt, Carolina Olid, and Maija Gailis
Biogeosciences, 19, 5751–5777, https://doi.org/10.5194/bg-19-5751-2022, https://doi.org/10.5194/bg-19-5751-2022, 2022
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Salt marshes are thought to be important carbon sinks because of their ability to store carbon in their soils. We provide the first estimates of how much blue carbon is stored in salt marshes on the Pacific coast of Canada. We find that the carbon stored in the marshes is low compared to other marshes around the world, likely because of their young age. Still, the high marshes take up carbon at rates faster than the global average, making them potentially important carbon sinks in the future.
Jim Boonman, Mariet M. Hefting, Corine J. A. van Huissteden, Merit van den Berg, Jacobus (Ko) van Huissteden, Gilles Erkens, Roel Melman, and Ype van der Velde
Biogeosciences, 19, 5707–5727, https://doi.org/10.5194/bg-19-5707-2022, https://doi.org/10.5194/bg-19-5707-2022, 2022
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Draining peat causes high CO2 emissions, and rewetting could potentially help solve this problem. In the dry year 2020 we measured that subsurface irrigation reduced CO2 emissions by 28 % and 83 % on two research sites. We modelled a peat parcel and found that the reduction depends on seepage and weather conditions and increases when using pressurized irrigation or maintaining high ditchwater levels. We found that soil temperature and moisture are suitable as indicators of peat CO2 emissions.
Maiju Linkosalmi, Juha-Pekka Tuovinen, Olli Nevalainen, Mikko Peltoniemi, Cemal M. Taniş, Ali N. Arslan, Juuso Rainne, Annalea Lohila, Tuomas Laurila, and Mika Aurela
Biogeosciences, 19, 4747–4765, https://doi.org/10.5194/bg-19-4747-2022, https://doi.org/10.5194/bg-19-4747-2022, 2022
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Vegetation greenness was monitored with digital cameras in three northern peatlands during five growing seasons. The greenness index derived from the images was highest at the most nutrient-rich site. Greenness indicated the main phases of phenology and correlated with CO2 uptake, though this was mainly related to the common seasonal cycle. The cameras and Sentinel-2 satellite showed consistent results, but more frequent satellite data are needed for reliable detection of phenological phases.
Antonin Prijac, Laure Gandois, Laurent Jeanneau, Pierre Taillardat, and Michelle Garneau
Biogeosciences, 19, 4571–4588, https://doi.org/10.5194/bg-19-4571-2022, https://doi.org/10.5194/bg-19-4571-2022, 2022
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Pools are common features of peatlands. We documented dissolved organic matter (DOM) composition in pools and peat of an ombrotrophic boreal peatland to understand its origin and potential role in the peatland carbon budget. The survey reveals that DOM composition differs between pools and peat, although it is derived from the peat vegetation. We investigated which processes are involved and estimated that the contribution of carbon emissions from DOM processing in pools could be substantial.
Cordula Nina Gutekunst, Susanne Liebner, Anna-Kathrina Jenner, Klaus-Holger Knorr, Viktoria Unger, Franziska Koebsch, Erwin Don Racasa, Sizhong Yang, Michael Ernst Böttcher, Manon Janssen, Jens Kallmeyer, Denise Otto, Iris Schmiedinger, Lucas Winski, and Gerald Jurasinski
Biogeosciences, 19, 3625–3648, https://doi.org/10.5194/bg-19-3625-2022, https://doi.org/10.5194/bg-19-3625-2022, 2022
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Methane emissions decreased after a seawater inflow and a preceding drought in freshwater rewetted coastal peatland. However, our microbial and greenhouse gas measurements did not indicate that methane consumers increased. Rather, methane producers co-existed in high numbers with their usual competitors, the sulfate-cycling bacteria. We studied the peat soil and aimed to cover the soil–atmosphere continuum to better understand the sources of methane production and consumption.
Liam Heffernan, Maria A. Cavaco, Maya P. Bhatia, Cristian Estop-Aragonés, Klaus-Holger Knorr, and David Olefeldt
Biogeosciences, 19, 3051–3071, https://doi.org/10.5194/bg-19-3051-2022, https://doi.org/10.5194/bg-19-3051-2022, 2022
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Permafrost thaw in peatlands leads to waterlogged conditions, a favourable environment for microbes producing methane (CH4) and high CH4 emissions. High CH4 emissions in the initial decades following thaw are due to a vegetation community that produces suitable organic matter to fuel CH4-producing microbes, along with warm and wet conditions. High CH4 emissions after thaw persist for up to 100 years, after which environmental conditions are less favourable for microbes and high CH4 emissions.
Julia Gensel, Marc Steven Humphries, Matthias Zabel, David Sebag, Annette Hahn, and Enno Schefuß
Biogeosciences, 19, 2881–2902, https://doi.org/10.5194/bg-19-2881-2022, https://doi.org/10.5194/bg-19-2881-2022, 2022
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We investigated organic matter (OM) and plant-wax-derived biomarkers in sediments and plants along the Mkhuze River to constrain OM's origin and transport pathways within South Africa's largest freshwater wetland. Presently, it efficiently captures OM, so neither transport from upstream areas nor export from the swamp occurs. Thus, we emphasize that such geomorphological features can alter OM provenance, questioning the assumption of watershed-integrated information in downstream sediments.
Petri Kiuru, Marjo Palviainen, Tiia Grönholm, Maarit Raivonen, Lukas Kohl, Vincent Gauci, Iñaki Urzainki, and Annamari Laurén
Biogeosciences, 19, 1959–1977, https://doi.org/10.5194/bg-19-1959-2022, https://doi.org/10.5194/bg-19-1959-2022, 2022
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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.
Rey Harvey Suello, Simon Lucas Hernandez, Steven Bouillon, Jean-Philippe Belliard, Luis Dominguez-Granda, Marijn Van de Broek, Andrea Mishell Rosado Moncayo, John Ramos Veliz, Karem Pollette Ramirez, Gerard Govers, and Stijn Temmerman
Biogeosciences, 19, 1571–1585, https://doi.org/10.5194/bg-19-1571-2022, https://doi.org/10.5194/bg-19-1571-2022, 2022
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This research shows indications that the age of the mangrove forest and its position along a deltaic gradient (upstream–downstream) play a vital role in the amount and sources of carbon stored in the mangrove sediments. Our findings also imply that carbon capture by the mangrove ecosystem itself contributes partly but relatively little to long-term sediment organic carbon storage. This finding is particularly relevant for budgeting the potential of mangrove ecosystems to mitigate climate change.
Raghab Ray, Rempei Suwa, Toshihiro Miyajima, Jeffrey Munar, Masaya Yoshikai, Maria Lourdes San Diego-McGlone, and Kazuo Nadaoka
Biogeosciences Discuss., https://doi.org/10.5194/bg-2021-359, https://doi.org/10.5194/bg-2021-359, 2022
Revised manuscript accepted for BG
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Mangroves are blue carbon ecosystems known to store large amounts of organic carbon in the sediments. This study is a first attempt to apply a chrono sequence (or space-for-time substitution) approach to evaluate the distribution and accumulation rate of carbon in a 30 year (max age) restored mangrove forest. Using this approach, the contribution of restored or planted mangroves to sedimentary organic carbon presents an increasing pattern with mangrove age.
Hao Tang, Susanne Liebner, Svenja Reents, Stefanie Nolte, Kai Jensen, Fabian Horn, and Peter Mueller
Biogeosciences, 18, 6133–6146, https://doi.org/10.5194/bg-18-6133-2021, https://doi.org/10.5194/bg-18-6133-2021, 2021
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We examined if sea-level rise and plant genotype interact to affect soil microbial functioning in a mesocosm experiment using two genotypes of a dominant salt-marsh grass characterized by differences in flooding sensitivity. Larger variability in microbial community structure, enzyme activity, and litter breakdown in soils with the more sensitive genotype supports our hypothesis that effects of climate change on soil microbial functioning can be controlled by plant intraspecific adaptations.
Naima Iram, Emad Kavehei, Damien T. Maher, Stuart E. Bunn, Mehran Rezaei Rashti, Bahareh Shahrabi Farahani, and Maria Fernanda Adame
Biogeosciences, 18, 5085–5096, https://doi.org/10.5194/bg-18-5085-2021, https://doi.org/10.5194/bg-18-5085-2021, 2021
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Greenhouse gas emissions were measured and compared from natural coastal wetlands and their converted agricultural lands across annual seasonal cycles in tropical Australia. Ponded pastures emitted ~ 200-fold-higher methane than any other tested land use type, suggesting the highest greenhouse gas mitigation potential and financial incentives by the restoration of ponded pastures to natural coastal wetlands.
Pavel Alekseychik, Aino Korrensalo, Ivan Mammarella, Samuli Launiainen, Eeva-Stiina Tuittila, Ilkka Korpela, and Timo Vesala
Biogeosciences, 18, 4681–4704, https://doi.org/10.5194/bg-18-4681-2021, https://doi.org/10.5194/bg-18-4681-2021, 2021
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Bogs of northern Eurasia represent a major type of peatland ecosystem and contain vast amounts of carbon, but carbon balance monitoring studies on bogs are scarce. The current project explores 6 years of carbon balance data obtained using the state-of-the-art eddy-covariance technique at a Finnish bog Siikaneva. The results reveal relatively low interannual variability indicative of ecosystem resilience to both cool and hot summers and provide new insights into the seasonal course of C fluxes.
Timea Katona, Benjamin Silas Gilfedder, Sven Frei, Matthias Bücker, and Adrian Flores-Orozco
Biogeosciences, 18, 4039–4058, https://doi.org/10.5194/bg-18-4039-2021, https://doi.org/10.5194/bg-18-4039-2021, 2021
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We used electrical geophysical methods to map variations in the rates of microbial activity within a wetland. Our results show that the highest electrical conductive and capacitive properties relate to the highest concentrations of phosphates, carbon, and iron; thus, we can use them to characterize the geometry of the biogeochemically active areas or hotspots.
Jurek Müller and Fortunat Joos
Biogeosciences, 18, 3657–3687, https://doi.org/10.5194/bg-18-3657-2021, https://doi.org/10.5194/bg-18-3657-2021, 2021
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We present long-term projections of global peatland area and carbon with a continuous transient history since the Last Glacial Maximum. Our novel results show that large parts of today’s northern peatlands are at risk from past and future climate change, with larger emissions clearly connected to larger risks. The study includes comparisons between different emission and land-use scenarios, driver attribution through factorial simulations, and assessments of uncertainty from climate forcing.
Lianlian Zhu, Zhengmiao Deng, Yonghong Xie, Xu Li, Feng Li, Xinsheng Chen, Yeai Zou, Chengyi Zhang, and Wei Wang
Biogeosciences, 18, 1–11, https://doi.org/10.5194/bg-18-1-2021, https://doi.org/10.5194/bg-18-1-2021, 2021
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We conducted a Carex brevicuspis leaf litter input experiment to clarify the intrinsic factors controlling litter decomposition and quantify its contribution to the soil organic carbon pool at different water levels. Our results revealed that the water level in natural wetlands influenced litter decomposition mainly by leaching and microbial activity, by extension, and affected the wetland surface carbon pool.
Robert J. Parker, Chris Wilson, A. Anthony Bloom, Edward Comyn-Platt, Garry Hayman, Joe McNorton, Hartmut Boesch, and Martyn P. Chipperfield
Biogeosciences, 17, 5669–5691, https://doi.org/10.5194/bg-17-5669-2020, https://doi.org/10.5194/bg-17-5669-2020, 2020
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Wetlands contribute the largest uncertainty to the atmospheric methane budget. WetCHARTs is a simple, data-driven model that estimates wetland emissions using observations of precipitation and temperature. We perform the first detailed evaluation of WetCHARTs against satellite data and find it performs well in reproducing the observed wetland methane seasonal cycle for the majority of wetland regions. In regions where it performs poorly, we highlight incorrect wetland extent as a key reason.
Jurek Müller and Fortunat Joos
Biogeosciences, 17, 5285–5308, https://doi.org/10.5194/bg-17-5285-2020, https://doi.org/10.5194/bg-17-5285-2020, 2020
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We present an in-depth model analysis of transient peatland area and carbon dynamics over the last 22 000 years. Our novel results show that the consideration of both gross positive and negative area changes are necessary to understand the transient evolution of peatlands and their net effect on atmospheric carbon. The study includes the attributions to drivers through factorial simulations, assessments of uncertainty from climate forcing, and determination of the global net carbon balance.
Lilli Zeh, Marie Theresa Igel, Judith Schellekens, Juul Limpens, Luca Bragazza, and Karsten Kalbitz
Biogeosciences, 17, 4797–4813, https://doi.org/10.5194/bg-17-4797-2020, https://doi.org/10.5194/bg-17-4797-2020, 2020
Jérémy Guilhen, Ahmad Al Bitar, Sabine Sauvage, Marie Parrens, Jean-Michel Martinez, Gwenael Abril, Patricia Moreira-Turcq, and José-Miguel Sánchez-Pérez
Biogeosciences, 17, 4297–4311, https://doi.org/10.5194/bg-17-4297-2020, https://doi.org/10.5194/bg-17-4297-2020, 2020
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The quantity of greenhouse gases (GHGs) released to the atmosphere by human industries and agriculture, such as carbon dioxide (CO2) and nitrous oxide (N2O), has been constantly increasing for the last few decades.
This work develops a methodology which makes consistent both satellite observations and modelling of the Amazon basin to identify and quantify the role of wetlands in GHG emissions. We showed that these areas produce non-negligible emissions and are linked to land use.
Thomas Rosset, Stéphane Binet, Jean-Marc Antoine, Emilie Lerigoleur, François Rigal, and Laure Gandois
Biogeosciences, 17, 3705–3722, https://doi.org/10.5194/bg-17-3705-2020, https://doi.org/10.5194/bg-17-3705-2020, 2020
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Peatlands export a large amount of DOC through inland waters. This study aims at identifying the mechanisms controlling the DOC concentration at the outlet of two mountainous peatlands in the French Pyrenees. Peat water temperature and water table dynamics are shown to drive seasonal- and event-scale DOC concentration variation. According to water recession times, peatlands appear as complexes of different hydrological and biogeochemical units supplying inland waters at different rates.
David Holl, Eva-Maria Pfeiffer, and Lars Kutzbach
Biogeosciences, 17, 2853–2874, https://doi.org/10.5194/bg-17-2853-2020, https://doi.org/10.5194/bg-17-2853-2020, 2020
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We measured greenhouse gas (GHG) fluxes at a bog site in northwestern Germany that has been heavily degraded by peat mining. During the 2-year investigation period, half of the area was still being mined, whereas the remaining half had been rewetted shortly before. We could therefore estimate the impact of rewetting on GHG flux dynamics. Rewetting had a considerable effect on the annual GHG balance and led to increased (up to 84 %) methane and decreased (up to 40 %) carbon dioxide release.
Jacob S. Diamond, Daniel L. McLaughlin, Robert A. Slesak, and Atticus Stovall
Biogeosciences, 17, 901–915, https://doi.org/10.5194/bg-17-901-2020, https://doi.org/10.5194/bg-17-901-2020, 2020
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Many wetland systems exhibit lumpy, or uneven, soil surfaces where higher points are called hummocks and lower points are called hollows. We found that, while hummocks extended only ~ 20 cm above hollow surfaces, they exhibited distinct plant communities, plant growth, and soil properties. Differences between hummocks and hollows were the greatest in wetter sites, supporting the hypothesis that plants create and maintain their own hummocks in response to saturated soil conditions.
Terhi Riutta, Aino Korrensalo, Anna M. Laine, Jukka Laine, and Eeva-Stiina Tuittila
Biogeosciences, 17, 727–740, https://doi.org/10.5194/bg-17-727-2020, https://doi.org/10.5194/bg-17-727-2020, 2020
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We studied the role of plant species groups in peatland methane fluxes under natural conditions and lowered water level. At a natural water level, sedges and mosses increased the fluxes. At a lower water level, the impact of plant groups on the fluxes was small. Only at a high water level did vegetation regulate the fluxes. The results are relevant for assessing peatland methane fluxes in a changing climate, as peatland water level and vegetation are predicted to change.
M. Graham Clark, Elyn R. Humphreys, and Sean K. Carey
Biogeosciences, 17, 667–682, https://doi.org/10.5194/bg-17-667-2020, https://doi.org/10.5194/bg-17-667-2020, 2020
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Natural and restored wetlands typically emit methane to the atmosphere. However, we found that a wetland constructed after oil sand mining in boreal Canada using organic soils from local peatlands had negligible emissions of methane in its first 3 years. Methane production was likely suppressed due to an abundance of alternate inorganic electron acceptors. Methane emissions may increase in the future if the alternate electron acceptors continue to decrease.
Hendrik Reuter, Julia Gensel, Marcus Elvert, and Dominik Zak
Biogeosciences, 17, 499–514, https://doi.org/10.5194/bg-17-499-2020, https://doi.org/10.5194/bg-17-499-2020, 2020
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Using infrared spectroscopy, we developed a routine to disentangle microbial nitrogen (N) and plant N in decomposed litter. In a decomposition experiment in three wetland soils, this routine revealed preferential protein depolymerization as a decomposition-site-dependent parameter, unaffected by variations in initial litter N content. In Sphagnum peat, preferential protein depolymerization led to a N depletion of still-unprocessed litter tissue, i.e., a gradual loss of litter quality.
Kevan J. Minick, Bhaskar Mitra, Asko Noormets, and John S. King
Biogeosciences, 16, 4671–4686, https://doi.org/10.5194/bg-16-4671-2019, https://doi.org/10.5194/bg-16-4671-2019, 2019
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Sea level rise alters hydrology and vegetation in coastal wetlands. We studied effects of freshwater, saltwater, and wood on soil microbial activity in a freshwater forested wetland. Saltwater reduced CO2/CH4 production compared to freshwater, suggesting large changes in greenhouse gas production and microbial activity are possible due to saltwater intrusion into freshwater wetlands but that the availability of C in the form of dead wood (as forests transition to marsh) may alter the magnitude.
Jyrki Jauhiainen, Jukka Alm, Brynhildur Bjarnadottir, Ingeborg Callesen, Jesper R. Christiansen, Nicholas Clarke, Lise Dalsgaard, Hongxing He, Sabine Jordan, Vaiva Kazanavičiūtė, Leif Klemedtsson, Ari Lauren, Andis Lazdins, Aleksi Lehtonen, Annalea Lohila, Ainars Lupikis, Ülo Mander, Kari Minkkinen, Åsa Kasimir, Mats Olsson, Paavo Ojanen, Hlynur Óskarsson, Bjarni D. Sigurdsson, Gunnhild Søgaard, Kaido Soosaar, Lars Vesterdal, and Raija Laiho
Biogeosciences, 16, 4687–4703, https://doi.org/10.5194/bg-16-4687-2019, https://doi.org/10.5194/bg-16-4687-2019, 2019
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We collated peer-reviewed publications presenting GHG flux data for drained organic forest soils in boreal and temperate climate zones, focusing on data that have been used, or have the potential to be used, for estimating net annual soil GHG emission/removals. We evaluated the methods in data collection and identified major gaps in background/environmental data. Based on these, we developed suggestions for future GHG data collection to increase data applicability in syntheses and inventories.
Steffen Buessecker, Kaitlyn Tylor, Joshua Nye, Keith E. Holbert, Jose D. Urquiza Muñoz, Jennifer B. Glass, Hilairy E. Hartnett, and Hinsby Cadillo-Quiroz
Biogeosciences, 16, 4601–4612, https://doi.org/10.5194/bg-16-4601-2019, https://doi.org/10.5194/bg-16-4601-2019, 2019
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We investigated the potential for chemical reduction of nitrite into nitrous oxide (N2O) in soils from tropical peat. Among treatments, irradiation resulted in the lowest biological interference and least change of native soil chemistry (iron and organic matter). Nitrite depletion was as high in live or irradiated soils, and N2O production was significant in all tests. Thus, nonbiological production of N2O may be widely underestimated in wetlands and tropical peatlands.
Ward Swinnen, Nils Broothaerts, and Gert Verstraeten
Biogeosciences, 16, 3977–3996, https://doi.org/10.5194/bg-16-3977-2019, https://doi.org/10.5194/bg-16-3977-2019, 2019
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In this study, a new model is presented, which was specifically designed to study the development and carbon storage of blanket peatlands since the last ice age. In the past, two main processes (declining forest cover and rising temperatures) have been proposed as drivers of blanket peatland development on the British Isles. The simulations performed in this study support the temperature hypothesis for the blanket peatlands in the Cairngorms Mountains of central Scotland.
David Holl, Verónica Pancotto, Adrian Heger, Sergio Jose Camargo, and Lars Kutzbach
Biogeosciences, 16, 3397–3423, https://doi.org/10.5194/bg-16-3397-2019, https://doi.org/10.5194/bg-16-3397-2019, 2019
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We present 2 years of eddy covariance carbon dioxide flux data from two Southern Hemisphere peatlands on Tierra del Fuego. One of the investigated sites is a type of bog exclusive to the Southern Hemisphere, which is dominated by vascular, cushion-forming plants and is particularly understudied. One result of this study is that these cushion bogs apparently are highly productive in comparison to Northern and Southern Hemisphere moss-dominated bogs.
Liudmila S. Shirokova, Artem V. Chupakov, Svetlana A. Zabelina, Natalia V. Neverova, Dahedrey Payandi-Rolland, Carole Causserand, Jan Karlsson, and Oleg S. Pokrovsky
Biogeosciences, 16, 2511–2526, https://doi.org/10.5194/bg-16-2511-2019, https://doi.org/10.5194/bg-16-2511-2019, 2019
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Regardless of the size and landscape context of surface water in frozen peatland in NE Europe, the bio- and photo-degradability of dissolved organic matter (DOM) over a 1-month incubation across a range of temperatures was below 10 %. We challenge the paradigm of dominance of photolysis and biodegradation in DOM processing in surface waters from frozen peatland, and we hypothesize peat pore-water DOM degradation and respiration of sediments to be the main drivers of CO2 emission in this region.
Elisa Männistö, Aino Korrensalo, Pavel Alekseychik, Ivan Mammarella, Olli Peltola, Timo Vesala, and Eeva-Stiina Tuittila
Biogeosciences, 16, 2409–2421, https://doi.org/10.5194/bg-16-2409-2019, https://doi.org/10.5194/bg-16-2409-2019, 2019
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We studied methane emitted as episodic bubble release (ebullition) from water and bare peat surfaces of a boreal bog over three years. There was more ebullition from water than from bare peat surfaces, and it was controlled by peat temperature, water level, atmospheric pressure and the weekly temperature sum. However, the contribution of methane bubbles to the total ecosystem methane emission was small. This new information can be used to improve process models of peatland methane dynamics.
Franziska Koebsch, Matthias Winkel, Susanne Liebner, Bo Liu, Julia Westphal, Iris Schmiedinger, Alejandro Spitzy, Matthias Gehre, Gerald Jurasinski, Stefan Köhler, Viktoria Unger, Marian Koch, Torsten Sachs, and Michael E. Böttcher
Biogeosciences, 16, 1937–1953, https://doi.org/10.5194/bg-16-1937-2019, https://doi.org/10.5194/bg-16-1937-2019, 2019
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In natural coastal wetlands, high supplies of marine sulfate suppress methane production. We found these natural methane suppression mechanisms to be suspended by humane interference in a brackish wetland. Here, diking and freshwater rewetting had caused an efficient depletion of the sulfate reservoir and opened up favorable conditions for an intensive methane production. Our results demonstrate how human disturbance can turn coastal wetlands into distinct sources of the greenhouse gas methane.
Luke C. Jeffrey, Damien T. Maher, Scott G. Johnston, Kylie Maguire, Andrew D. L. Steven, and Douglas R. Tait
Biogeosciences, 16, 1799–1815, https://doi.org/10.5194/bg-16-1799-2019, https://doi.org/10.5194/bg-16-1799-2019, 2019
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Wetlands represent the largest natural source of methane (CH4), so understanding CH4 drivers is important for management and climate models. We compared several CH4 pathways of a remediated subtropical Australian wetland. We found permanently inundated sites emitted more CH4 than seasonally inundated sites and that the soil properties of each site corresponded to CH4 emissions. This suggests that selective wetland remediation of favourable soil types may help to mitigate unwanted CH4 emissions.
Ryo Shingubara, Atsuko Sugimoto, Jun Murase, Go Iwahana, Shunsuke Tei, Maochang Liang, Shinya Takano, Tomoki Morozumi, and Trofim C. Maximov
Biogeosciences, 16, 755–768, https://doi.org/10.5194/bg-16-755-2019, https://doi.org/10.5194/bg-16-755-2019, 2019
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(1) Wetting event with extreme precipitation increased methane emission from wetland, especially two summers later, despite the decline in water level after the wetting. (2) Isotopic compositions of methane in soil pore water suggested enhancement of production and less significance of oxidation in the following two summers after the wetting event. (3) Duration of water saturation in the active layer may be important for predicting methane emission after a wetting event in permafrost ecosystems.
Wiebke Münchberger, Klaus-Holger Knorr, Christian Blodau, Verónica A. Pancotto, and Till Kleinebecker
Biogeosciences, 16, 541–559, https://doi.org/10.5194/bg-16-541-2019, https://doi.org/10.5194/bg-16-541-2019, 2019
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Processes governing CH4 dynamics have been scarcely studied in southern hemispheric bogs. These can be dominated by cushion-forming plants with deep and dense roots suppressing emissions. Here we demonstrate how the spatial distribution of root activity drives a pronounced pattern of CH4 emissions, likewise also possible in densely rooted northern bogs. We conclude that presence of cushion vegetation as a proxy for negligible CH4 emissions from cushion bogs needs to be interpreted with caution.
Sarah Cook, Mick J. Whelan, Chris D. Evans, Vincent Gauci, Mike Peacock, Mark H. Garnett, Lip Khoon Kho, Yit Arn Teh, and Susan E. Page
Biogeosciences, 15, 7435–7450, https://doi.org/10.5194/bg-15-7435-2018, https://doi.org/10.5194/bg-15-7435-2018, 2018
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This paper presents the first comprehensive assessment of fluvial organic carbon loss from oil palm plantations on tropical peat: a carbon loss pathway previously unaccounted for from carbon budgets. Carbon in the water draining four plantations in Sarawak was monitored across a 1-year period. Greater fluvial carbon losses were linked to sites with lower water tables. These data will be used to complete the carbon budget from these ecosystems and assess the full impact of this land conversion.
Ariane Arias-Ortiz, Pere Masqué, Jordi Garcia-Orellana, Oscar Serrano, Inés Mazarrasa, Núria Marbà, Catherine E. Lovelock, Paul S. Lavery, and Carlos M. Duarte
Biogeosciences, 15, 6791–6818, https://doi.org/10.5194/bg-15-6791-2018, https://doi.org/10.5194/bg-15-6791-2018, 2018
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Efforts to include tidal marsh, mangrove and seagrass ecosystems in existing carbon mitigation strategies are limited by a lack of estimates of carbon accumulation rates (CARs). We discuss the use of 210Pb dating to determine CARs in these habitats, which are often composed of heterogeneous sediments and affected by sedimentary processes. Results show that obtaining reliable geochronologies in these systems is ambitious, but estimates of mean 100-year CARs are mostly secure within 20 % error.
Danielle D. Radu and Tim P. Duval
Biogeosciences, 15, 3937–3951, https://doi.org/10.5194/bg-15-3937-2018, https://doi.org/10.5194/bg-15-3937-2018, 2018
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Climate change can shift rainfall into fewer, more intense events with longer dry periods, leading to changes in peatland hydrology and carbon cycling. We manipulated rain events over three peatland plant types (moss, sedge, and shrub). We found increasing regime intensity led to drier surface soils and deeper water tables, reducing plant carbon uptake. Mosses became sources of CO2 after >3 consecutive dry days. This study shows peatlands may become smaller sinks for carbon due to rain changes.
Peter Mueller, Lisa M. Schile-Beers, Thomas J. Mozdzer, Gail L. Chmura, Thomas Dinter, Yakov Kuzyakov, Alma V. de Groot, Peter Esselink, Christian Smit, Andrea D'Alpaos, Carles Ibáñez, Magdalena Lazarus, Urs Neumeier, Beverly J. Johnson, Andrew H. Baldwin, Stephanie A. Yarwood, Diana I. Montemayor, Zaichao Yang, Jihua Wu, Kai Jensen, and Stefanie Nolte
Biogeosciences, 15, 3189–3202, https://doi.org/10.5194/bg-15-3189-2018, https://doi.org/10.5194/bg-15-3189-2018, 2018
Karel Castro-Morales, Thomas Kleinen, Sonja Kaiser, Sönke Zaehle, Fanny Kittler, Min Jung Kwon, Christian Beer, and Mathias Göckede
Biogeosciences, 15, 2691–2722, https://doi.org/10.5194/bg-15-2691-2018, https://doi.org/10.5194/bg-15-2691-2018, 2018
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We present year-round methane emissions from wetlands in Northeast Siberia that were simulated with a land surface model. Ground-based flux measurements from the same area were used for evaluation of the model results, finding a best agreement with the observations in the summertime emissions that take place in this region predominantly through plants. During winter, methane emissions through the snow contribute 4 % of the total annual methane budget, but these are still underestimated.
Aino Korrensalo, Elisa Männistö, Pavel Alekseychik, Ivan Mammarella, Janne Rinne, Timo Vesala, and Eeva-Stiina Tuittila
Biogeosciences, 15, 1749–1761, https://doi.org/10.5194/bg-15-1749-2018, https://doi.org/10.5194/bg-15-1749-2018, 2018
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We measured methane fluxes of a boreal bog from six different plant community types in 2012–2014. We found only little variation in methane fluxes among plant community types. Peat temperature as well as both leaf area of plant species with air channels and of all vegetation are important factors controlling the fluxes. We also detected negative net fluxes indicating methane consumption each year. Our results can be used to improve the models of peatland methane dynamics under climate change.
Magnus Gålfalk, Martin Karlson, Patrick Crill, Philippe Bousquet, and David Bastviken
Biogeosciences, 15, 1549–1557, https://doi.org/10.5194/bg-15-1549-2018, https://doi.org/10.5194/bg-15-1549-2018, 2018
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We describe a quick in situ method for mapping ground surface cover, calculating areas of each surface type in a 10 x 10 m plot for each measurement. The method is robust, weather-independent, easily carried out, and uses wide-field imaging with a standard remote-controlled camera mounted on a very long extendible monopod from a height of 3–4.5 m. The method enables collection of detailed field reference data, critical in many remote sensing applications, such as wetland mapping.
Olli Peltola, Maarit Raivonen, Xuefei Li, and Timo Vesala
Biogeosciences, 15, 937–951, https://doi.org/10.5194/bg-15-937-2018, https://doi.org/10.5194/bg-15-937-2018, 2018
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Emission via bubbling, i.e. ebullition, is one of the main CH4 emission pathways from wetlands to the atmosphere, yet it is still coarsely represented in wetland CH4 models. In this study three ebullition modelling approaches are evaluated. Modeled annual CH4 emissions were similar, whereas temporal variability in CH4 emissions varied an order of magnitude between the approaches. Hence realistic description of ebullition is needed when models are compared to and calibrated against measurements.
Tracy Elsey-Quirk and Viktoria Unger
Biogeosciences, 15, 379–397, https://doi.org/10.5194/bg-15-379-2018, https://doi.org/10.5194/bg-15-379-2018, 2018
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Salt marshes have high rates of plant productivity and carbon accumulation. For this study, we found that differences in environmental conditions between estuary types were important in determining the source and stability of soil organic carbon. Specifically, sediment availability was extremely important in promoting high plant productivity and carbon accumulation in an estuary which was sediment-limited. In a sediment-rich estuary vegetation–soil-carbon relationships were weaker.
Jordan P. Goodrich, David I. Campbell, and Louis A. Schipper
Biogeosciences, 14, 4563–4576, https://doi.org/10.5194/bg-14-4563-2017, https://doi.org/10.5194/bg-14-4563-2017, 2017
Jonathan P. Ritson, Richard E. Brazier, Nigel J. D. Graham, Chris Freeman, Michael R. Templeton, and Joanna M. Clark
Biogeosciences, 14, 2891–2902, https://doi.org/10.5194/bg-14-2891-2017, https://doi.org/10.5194/bg-14-2891-2017, 2017
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Peatlands are a globally important store of carbon; however increased droughts in the future may affect their ability to sequester carbon. Using laboratory simulations we show that droughts, through exposure to oxygen, greatly increase the quantity and alter the quality of dissolved organic carbon (DOC) released from peat. Catchment management which keeps water tables high to limit oxygen exposure is therefore likely to deliver positive water quality outcomes.
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