Free atmospheric CO2 enrichment increased above ground biomass but did not affec symbiotic N2-fixation and soil carbon dynamics in a mixed deciduous stand in Wales
Hoosbeek, M.R. ; Lukac, M. ; Velthorst, E.J. ; Smith, A.R. ; Godbold, D. - \ 2011
Biogeosciences 8 (2011)2. - ISSN 1726-4170 - p. 353 - 364.
rotation poplar plantation - nitrogen-use efficiency - natural n-15 abundance - elevated co2 - organic-matter - pine forest - dinitrogen fixation - alnus-glutinosa - mineral soil - face
Through increases in net primary production (NPP), elevated CO2 is hypothesized to increase the amount of plant litter entering the soil. The fate of this extra carbon on the forest floor or in mineral soil is currently not clear. Moreover, increased rates of NPP can be maintained only if forests can escape nitrogen limitation. In a Free atmospheric CO2 Enrichment (FACE) experiment near Bangor, Wales, 4 ambient and 4 elevated [CO2] plots were planted with patches of Betula pendula, Alnus glutinosa and Fagus sylvatica on a former arable field. After 4 years, biomass averaged for the 3 species was 5497 (se 270) g m-2 in ambient and 6450 (se 130) g m-2 in elevated [CO2] plots, a significant increase of 17% (P = 0.018). During that time, only a shallow L forest floor litter layer had formed due to intensive bioturbation. Total soil C and N contents increased irrespective of treatment and species as a result of afforestation. We could not detect an additional C sink in the soil, nor were soil C stabilization processes affected by elevated [CO2]. We observed a decrease of leaf N content in Betula and Alnus under elevated [CO2], while the soil C/N ratio decreased regardless of CO2 treatment. The ratio of N taken up from the soil and by N2-fixation in Alnus was not affected by elevated [CO2]. We infer that increased nitrogen use efficiency is the mechanism by which increased NPP is sustained under elevated [CO2] at this site
Challenges in elevated CO2 experiments on forests
Calfapietra, C. ; Ainsworth, E.A. ; Beier, C. ; Godbold, D. ; Hoosbeek, M.R. - \ 2010
Trends in Plant Science 15 (2010)1. - ISSN 1360-1385 - p. 5 - 10.
atmospheric co2 - carbon-dioxide - climate-change - ecosystem responses - enrichment system - growth dynamics - air fumigation - design - spruce - ozone
Current forest Free Air CO2 Enrichment (FACE) experiments are reaching completion. Therefore, it is time to define the scientific goals and priorities of future experimental facilities. In this opinion article, we discuss the following three overarching issues (i) What are the most urgent scientific questions and how can they be addressed? (ii) What forest ecosystems should be investigated? (iii) Which other climate change factors should be coupled with elevated CO2 concentrations in future experiments to better predict the effects of climate change? Plantations and natural forests can have conflicting purposes for high productivity and environmental protection. However, in both cases the assessment of carbon balance and how this will be affected by elevated CO2 concentrations and the interacting climate change factors is the most pressing priority for future experiments.
|Effect of free atmospheric CO2 enrichment (FACE) on symbiotic N2-fixation and soil carbon content and stabilization in a mixed deciduous stand in Wales, UK
Hoosbeek, M.R. ; Godbold, D. - \ 2009
In: International Symposium on Soil Organic Matter Dynamics : Land Use, Management and Global Change. Colorado Springs, Colorado, USA, 6 - 9 July, 2009. - Colorado : Colorado State University - p. 19 - 19.
Mycorrhizal hyphal turnover as a dominant process for carbon input into soil organic matter
Godbold, D. ; Hoosbeek, M.R. ; Lukac, M. ; Francesca Cotrufo, M. ; Janssens, I.A. ; Ceulemans, R. ; Polle, A. ; Velthorst, E.J. ; Scarascia-Mugnozza, G. ; Angelis, P. de; Miglietta, F. ; Peressotti, A. - \ 2006
Plant and Soil 281 (2006)1-2. - ISSN 0032-079X - p. 15 - 24.
elevated atmospheric co2 - douglas-fir ecosystem - 1st growing-season - ectomycorrhizal fungi - forest ecosystems - external mycelium - root turnover - enrichment - nitrogen - patterns
The atmospheric concentration of CO2 is predicted to reach double current levels by 2075. Detritus from aboveground and belowground plant parts constitutes the primary source of C for soil organic matter (SOM), and accumulation of SOM in forests may provide a significant mechanism to mitigate increasing atmospheric CO2 concentrations. In a poplar (three species) plantation exposed to ambient (380 ppm) and elevated (580 ppm) atmospheric CO2 concentrations using a Free Air Carbon Dioxide Enrichment (FACE) system, the relative importance of leaf litter decomposition, fine root and fungal turnover for C incorporation into SOM was investigated. A technique using cores of soil in which a C-4 crop has been grown (delta C-13 -18.1 parts per thousand) inserted into the plantation and detritus from C-3 trees (delta C-13 -27 to -30 parts per thousand) was used to distinguish between old (native soil) and new (tree derived) soil C. In-growth cores using a fine mesh (39 mu m) to prevent in-growth of roots, but allow in-growth of fungal hyphae were used to assess contribution of fine roots and the mycorrhizal external mycelium to soil C during a period of three growing seasons (1999-2001). Across all species and treatments, the mycorrhizal external mycelium was the dominant pathway (62%) through which carbon entered the SOM pool, exceeding the input via leaf litter and fine root turnover. The input via the mycorrhizal external mycelium was not influenced by elevated CO2, but elevated atmospheric CO2 enhanced soil C inputs via fine root turnover. The turnover of the mycorrhizal external mycelium may be a fundamental mechanism for the transfer of root-derived C to SOM.
|Responses to elevated [CO2] of a short rotation multispecies poplar plantation: the POPFACE/EUROFACE experiment
Scarascia-Mugnozza, G. ; Calfapietra, C. ; Ceulemans, R. ; Gielen, B. ; Cotrufo, M.F. ; DeAngelis, P. ; Godbold, D. ; Hoosbeek, M.R. ; Kull, O. ; Lukac, M. ; Marek, M. ; Miglietta, F. ; Polle, A. ; Raines, C. ; Sabatti, M. ; Anselmi, N. ; Taylor, G. - \ 2006
In: Managed Ecosystems and CO2 / Nösberger, J., Long, S.P., Norby, R.J., Stitt, M., Hendrey, G.R., Blum, H., Heidelberg : Springer-Verlag (Ecological Studies 187) - ISBN 9783540312369 - p. 173 - 185.
Woody biomass production during the second rotation of a bio-energy Populus plantation increases in a future high CO2 world
Liberloo, M. ; Calfapietra, C. ; Lukac, M. ; Godbold, D. ; Luos, Z.B. ; Polles, A. ; Hoosbeek, M.R. ; Kull, O. ; Marek, M. ; Rianes, Chr. ; Rubino, M. ; Taylors, G. ; Scarascia-Mugnozza, G. ; Ceulemans, R. - \ 2006
Global Change Biology 12 (2006)6. - ISSN 1354-1013 - p. 1094 - 1106.
elevated co2 - atmospheric co2 - poplar plantation - enrichment face - no3 availability - n-fertilization - hybrid poplar - water-stress - pinus-taeda - growth
The quickly rising atmospheric carbon dioxide (CO2)-levels, justify the need to explore all carbon (C) sequestration possibilities that might mitigate the current CO2 increase. Here, we report the likely impact of future increases in atmospheric CO2 on woody biomass production of three poplar species (Populus alba L. clone 2AS-11, Populus nigra L. clone Jean Pourtet and Populus×euramericana clone I-214). Trees were growing in a high-density coppice plantation during the second rotation (i.e., regrowth after coppice; 2002¿2004; POPFACE/EUROFACE). Six plots were studied, half of which were continuously fumigated with CO2 (FACE; free air carbon dioxide enrichment of 550 ppm). Half of each plot was fertilized to study the interaction between CO2 and nutrient fertilization. At the end of the second rotation, selective above- and belowground harvests were performed to estimate the productivity of this bio-energy plantation. Fertilization did not affect growth of the poplar trees, which was likely because of the high rates of fertilization during the previous agricultural land use. In contrast, elevated CO2 enhanced biomass production by up to 29%, and this stimulation did not differ between above- and belowground parts. The increased initial stump size resulting from elevated CO2 during the first rotation (1999¿2001) could not solely explain the observed final biomass increase. The larger leaf area index after canopy closure and the absence of any major photosynthetic acclimation after 6 years of fumigation caused the sustained CO2-induced biomass increase after coppice. These results suggest that, under future CO2 concentrations, managed poplar coppice systems may exhibit higher potential for C sequestration and, thus, help mitigate climate change when used as a source of C-neutral energy.
Global change and agro-forest ecosystems: Adaptation and mitigation in a FACE experiment on a poplar plantation
Scarascia-Mugnozza, G. ; Angelis, P. de; Sabatti, M. ; Calfapietra, C. ; Miglietta, F. ; Raines, C. ; Godbold, D. ; Hoosbeek, M.R. ; Taylor, G. ; Polle, A. ; Ceulemans, R. - \ 2005
Plant Biosystems 139 (2005)3. - ISSN 1126-3504 - p. 255 - 264.
elevated atmospheric co2 - carbon-dioxide - enrichment popface - short-rotation - mycorrhizal colonization - betula-papyrifera - field - responses - growth - soil
The objective of this research was to determine the functional responses of a cultivated, agro-forestry system, namely a poplar plantation, to actual and future atmospheric CO2 concentrations. Hence, this research has combined a fast growing, agro-forestry ecosystem, capable of elevated biomass production, with a large-scale Free Air Carbon Enrichment (FACE) system, one of the few available in the European Union on a forest tree stand. The FACE facility is located close to a natural CO2 source and is drawing scientists from several European countries, and from other continents, to closely cooperate and combine their scientific efforts on the same experimental system. Furthermore, this FACE apparatus utilizes a novel technology, originally developed by Italian institutions, based on the release into the atmosphere, at sonic velocity, of pure CO2 instead of an air-CO2 Mixture. The research activities conducted at the POPFACE site, on the responses of the tree plantation to future atmospheric conditions, have integrated observations at the leaf level, such as photosynthesis, respiration and transpiration, with measures carried out at the whole-tree and stand scale, such as canopy architecture, light interception and biomass production. Finally, the ecosystem dimension has also been analysed by studying root productivity and soil processes, host-parasite interactions, and carbon sequestration throughout a rotation. cycle of the stand.
Net carbon storage in a popular plantation (POPFACE) after three years of free-air CO2 enrichment
Gielen, B. ; Calfapietra, C. ; Lukac, M. ; Wittig, V.E. ; Angelis, P. de; Janssens, I.A. ; Moscatelli, M.C. ; Grego, S. ; Cotrufo, M.F. ; Godbold, D. ; Hoosbeek, M.R. ; Long, S. ; Miglietta, F. ; Polle, A. ; Bernacchi, C. ; Davey, P.A. ; Ceulemans, R. ; Scarascia-Mugnozza, G. - \ 2005
Tree Physiology 25 (2005)11. - ISSN 0829-318X - p. 1399 - 1408.
temperature response functions - elevated atmospheric co2 - soil organic-matter - limited photosynthesis - dioxide enrichment - microbial biomass - turnover - forest - populus - dynamics
A high-density plantation of three genotypes of Populus was exposed to an elevated concentration of carbon dioxide ([CO2]; 550 µmol mol¿1) from planting through canopy closure using a free-air CO2 enrichment (FACE) technique. The FACE treatment stimulated gross primary productivity by 22 and 11% in the second and third years, respectively. Partitioning of extra carbon (C) among C pools of different turnover rates is of critical interest; thus, we calculated net ecosystem productivity (NEP) to determine whether elevated atmospheric [CO2] will enhance net plantation C storage capacity. Free-air CO2 enrichment increased net primary productivity (NPP) of all genotypes by 21% in the second year and by 26% in the third year, mainly because of an increase in the size of C pools with relatively slow turnover rates (i.e., wood). In all genotypes in the FACE treatment, more new soil C was added to the total soil C pool compared with the control treatment. However, more old soil C loss was observed in the FACE treatment compared with the control treatment, possibly due to a priming effect from newly incorporated root litter. FACE did not significantly increase NEP, probably as a result of this priming effect.
More new carbon in the mineral soil of a poplar plantation under Free Air Carbon Erichment (POPFACE): Cause of increased priming effect?
Hoosbeek, M.R. ; Lukac, M. ; Dam, D. ; Godbold, D. ; Velthorst, E.J. ; Bondi, F.A. ; Peressotti, A. ; Cotrufo, M.F. ; Angelis, P. de; Scarascia-Mugnozza, G. - \ 2004
Global Biogeochemical Cycles 18 (2004)1. - ISSN 0886-6236 - 7 p.
elevated atmospheric co2 - organic-matter - terrestrial ecosystems - turnover - forest - storage - system - decomposition - mechanisms - feedbacks
 In order to establish suitability of forest ecosystems for long-term storage of C, it is necessary to characterize the effects of predicted increased atmospheric CO2 levels on the pools and fluxes of C within these systems. Since most C held in terrestrial ecosystems is in the soil, we assessed the influence of Free Air Carbon Enrichment (FACE) treatment on the total soil C content (C-total) and incorporation of litter derived C (C-new) into soil organic matter (SOM) in a fast growing poplar plantation. C-new was estimated by the C3/C4 stable isotope method. C-total contents increased under control and FACE respectively by 12 and 3%, i.e., 484 and 107 gC/m(2), while 704 and 926 gC/m(2) of new carbon was sequestered under control and FACE during the experiment. We conclude that FACE suppressed the increase of C-total and simultaneously increased C-new. We hypothesize that these opposite effects may be caused by a priming effect of the newly incorporated litter, where priming effect is defined as the stimulation of SOM decomposition caused by the addition of labile substrates.
|More new carbon in the mineral soil if a popular plantation under FACE (POPFACE)
Hoosbeek, M.R. ; Lukac, M. ; Dam, D. ; Godbold, D. ; Velthorst, E.J. ; Biondi, F.A. ; Peressotti, A. ; Gotrufo, M.F. ; Angelis, P. de; Scarascia-Mugnozza, G. - \ 2004
|Long-term responses of a poplar agroforestry system to elevated CO2: tree growth, biomass productivity and carbon pools
Scarascia-Mugnozza, G. ; Calfapietra, C. ; Gielen, B. ; Angelis, P. de; Liberloo, M. ; Lukac, M. ; Godbold, D. ; Cotrufo, M.F. ; Hoosbeek, M.R. ; Taylor, G. ; Raines, C. ; Marek, M. ; Kull, O. ; Miglietta, F. ; Polle, A. ; Ceulemans, R. - \ 2004