Carbon-nitrogen interactions in European forests and semi-natural vegetation - Part 2: Untangling climatic, edaphic, management and nitrogen deposition effects on carbon sequestration potentials
Flechard, Chris R.; Van Oijen, Marcel; Cameron, David R.et al.
Ecology, Evolution, Behavior and Systematics; Earth-Surface Processes
Abstract :
[en] The effects of atmospheric nitrogen deposition (Ndep) on carbon (C) sequestration in forests have often been assessed by relating differences in productivity to spatial variations of Ndep across a large geographic domain. These correlations generally suffer from covariation of other confounding variables related to climate and other growth-limiting factors, as well as large uncertainties in total (dryCwet) reactive nitrogen (Nr) deposition.We propose a methodology for untangling the effects of Ndep from those of meteorological variables, soil water retention capacity and stand age, using a mechanistic forest growth model in combination with eddy covariance CO2 exchange fluxes from a Europe-wide network of 22 forest flux towers. Total Nr deposition rates were estimated from local measurements as far as possible. The forest data were compared with data from natural or semi-natural, non-woody vegetation sites. The response of forest net ecosystem productivity to nitrogen deposition (dNEP= dNdep) was estimated after accounting for the effects on gross primary productivity (GPP) of the co-correlates by means of a meta-modelling standardization procedure, which resulted in a reduction by a factor of about 2 of the uncorrected, apparent dGPP=dNdep value. This model-enhanced analysis of the C and Ndep flux observations at the scale of the European network suggests a mean overall dNEP= dNdep response of forest lifetime C sequestration to Ndep of the order of 40 50 g C per g N, which is slightly larger but not significantly different from the range of estimates published in the most recent reviews. Importantly, patterns of gross primary and net ecosystem productivity versus Ndep were non-linear, with no further growth responses at high Ndep levels (Ndep >2.5 3 gNm2 yr1) but accompanied by increasingly large ecosystem N losses by leaching and gaseous emissions. The reduced increase in productivity per unit N deposited at high Ndep levels implies that the forecast increased Nr emissions and increased Ndep levels in large areas of Asia may not positively impact the continent s forest CO2 sink. The large level of unexplained variability in observed carbon sequestration efficiency (CSE) across sites further adds to the uncertainty in the dC=dN response.
Disciplines :
Environmental sciences & ecology
Author, co-author :
Flechard, Chris R. ; Institut National de la Recherche en Agriculture, Alimentation et Environnement (INRAE), UMR 1069 SAS, Rennes, France
Van Oijen, Marcel ; UK Centre for Ecology and Hydrology (UK CEH), Bush Estate, Penicuik, United Kingdom
Cameron, David R.; UK Centre for Ecology and Hydrology (UK CEH), Bush Estate, Penicuik, United Kingdom
De Vries, Wim; Wageningen University and Research, Environmental Systems Analysis Group, Wageningen, Netherlands
Ibrom, Andreas ; Department of Environmental Engineering, Technical University of Denmark, Kgs. Lyngby, Denmark
Buchmann, Nina; Department of Environmental Systems Science, Institute of Agricultural Sciences, ETH Zurich, Zurich, Switzerland
DIse, Nancy B.; UK Centre for Ecology and Hydrology (UK CEH), Bush Estate, Penicuik, United Kingdom
Janssens, Ivan A.; Centre of Excellence PLECO (Plant and Vegetation Ecology), Department of Biology, University of Antwerp, Wilrijk, Belgium
Neirynck, Johan; Environment and Climate, Research Institute for Nature and Forest (INBO), Geraardsbergen, Belgium
Montagnani, Leonardo ; Forest Services, Autonomous Province of Bolzano, Bolzano, Italy ; Faculty of Science and Technology, Free University of Bolzano, Bolzano, Italy
Varlagin, Andrej; A.N. Severtsov Institute of Ecology and Evolution, Russian Academy of Sciences, Moscow, Russian Federation
Loustau, Denis ; Bordeaux Sciences Agro, Institut National de la Recherche en Agriculture, Alimentation et Environnement (INRAE), UMR ISPA, Villenave d'Ornon, France
Legout, Arnaud; Institut National de la Recherche en Agriculture, Alimentation et Environnement (INRAE), BEF, Nancy, France
Ziemblińska, Klaudia ; Department of Meteorology, Poznań University of Life Sciences, Poznań, Poland
Aubinet, Marc ; Université de Liège - ULiège > Département GxABT > Biosystems Dynamics and Exchanges (BIODYNE)
Aurela, Mika ; Finnish Meteorological Institute, Climate System Research, Helsinki, Finland
Chojnicki, Bogdan H.; Laboratory of Bioclimatology, Department of Ecology and Environmental Protection, Poznań University of Life Sciences, Poznań, Poland
Drewer, Julia ; UK Centre for Ecology and Hydrology (UK CEH), Bush Estate, Penicuik, United Kingdom
Eugster, Werner ; Department of Environmental Systems Science, Institute of Agricultural Sciences, ETH Zurich, Zurich, Switzerland
Francez, Andre-Jean; University of Rennes, CNRS, UMR 6553 ECOBIO, Campus de Beaulieu, Rennes, France
Juszczak, Radoslaw; Laboratory of Bioclimatology, Department of Ecology and Environmental Protection, Poznań University of Life Sciences, Poznań, Poland
Kitzler, Barbara ; Federal Research and Training Centre for Forests, Natural Hazards and Landscape, Vienna, Austria
Kutsch, Werner L. ; Integrated Carbon Observation System (ICOS ERIC) Head Office, Helsinki, Finland
Lohila, Annalea ; Finnish Meteorological Institute, Climate System Research, Helsinki, Finland ; Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki, Finland
Longdoz, Bernard ; Université de Liège - ULiège > Département GxABT > Biosystems Dynamics and Exchanges (BIODYNE)
Matteucci, Giorgio; National Research Council of Italy, Institute for Agriculture and Forestry Systems in the Mediterranean (CNR-ISAFOM), Ercolano (NA), Italy
Moreaux, Virginie; Bordeaux Sciences Agro, Institut National de la Recherche en Agriculture, Alimentation et Environnement (INRAE), UMR ISPA, Villenave d'Ornon, France ; Institute for Geosciences and Environmental Research (IGE), UMR 5001, Université Grenoble Alpes, CNRS, IRD, Grenoble Institute of Technology, Grenoble, France
Neftel, Albrecht; NRE, Wohlen bei Bern, Switzerland
Olejnik, Janusz ; Department of Meteorology, Poznań University of Life Sciences, Poznań, Poland ; Department of Matter and Energy Fluxes, Global Change Research Centre, AS CR, Brno, Czech Republic
Sanz, Maria J.; Ikerbasque Foundation and Basque Centre for Climate Change, Sede Building 1, Scientific Campus of the University of the Basque Country, Leioa, Biscay, Spain
Siemens, Jan; Institute of Soil Science and Soil Conservation, IFZ Research Centre for Biosystems, Land Use and Nutrition, Justus Liebig University Giessen, Giessen, Germany
Vesala, Timo; Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki, Finland ; Institute for Atmospheric and Earth System Research/Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, Helsinki, Finland
Vincke, Caroline; Earth and Life Institute (Environmental Sciences), Université Catholique de Louvain, Louvain-la-Neuve, Belgium
Nemitz, Eiko ; UK Centre for Ecology and Hydrology (UK CEH), Bush Estate, Penicuik, United Kingdom
Zechmeister-Boltenstern, Sophie; Institute of Soil Research, Department of Forest and Soil Sciences, University of Natural Resources and Life Sciences Vienna, Vienna, Austria
Butterbach-Bahl, Klaus; Karlsruhe Institute of Technology (KIT), Institute of Meteorology and Climate Research, Atmospheric Environmental Research (IMK-IFU), Garmisch-Partenkirchen, Germany
Skiba, Ute M.; UK Centre for Ecology and Hydrology (UK CEH), Bush Estate, Penicuik, United Kingdom
Sutton, Mark A. ; UK Centre for Ecology and Hydrology (UK CEH), Bush Estate, Penicuik, United Kingdom
Carbon-nitrogen interactions in European forests and semi-natural vegetation - Part 2: Untangling climatic, edaphic, management and nitrogen deposition effects on carbon sequestration potentials
Acknowledgements. The authors gratefully acknowledge financial support by the European Commission through the two FP6 integrated projects CarboEurope-IP (project no. GOCE-CT-2003-505572) and NitroEurope Integrated Project (project no. 017841), the FP7 ECLAIRE project (grant agreement no. 282910), and the ABBA COST Action ES0804. We are also thankful for funding from the French GIP-ECOFOR consortium under the F-ORE-T forest observation and experimentation network, as well as from the MDM-2017-0714 Spanish grant. We are grateful to Janne Korho-nen, Mari Pihlatie and Dave Simpson for their comments on the paper. Finalization of the paper was supported by the UK Natural Environment Research Council award number NE/R016429/1 as part of the UK-SCAPE programme delivering national capability. We also wish to thank two anonymous referees for their constructive criticism of the paper.Financial support. This research has been supported by the Eu-
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