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Klaus M, Öquist M, Macháčová K. Tree stem-atmosphere greenhouse gas fluxes in a boreal riparian forest. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 954:176243. [PMID: 39278477 DOI: 10.1016/j.scitotenv.2024.176243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2024] [Revised: 08/22/2024] [Accepted: 09/11/2024] [Indexed: 09/18/2024]
Abstract
Tree stems exchange greenhouse gases with the atmosphere but the magnitude, variability and drivers of these fluxes remain poorly understood. Here, we report stem fluxes of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) in a boreal riparian forest, and investigate their spatiotemporal variability and ecosystem level importance. For two years, we measured CO2 and CH4 fluxes on a monthly basis in 14 spruces (Picea abies) and 14 birches (Betula pendula) growing near a headwater stream affected by historic ditching. We also measured N2O fluxes on three occasions. All tree stems were net emitters of CO2 and CH4, while N2O fluxes were around zero. CO2 fluxes correlated strongly with air temperature and peaked in summer. CH4 fluxes correlated modestly with air temperature and solar radiation and peaked in late winter and summer. Trees with larger stem diameter emitted more CO2 and less CH4 and trees closer to the stream emitted more CO2 and CH4. The CO2 and CH4 fluxes did not differ between spruce and birch, but correlations of CO2 fluxes with stem diameter and distance to stream differed between the tree species. The absence of vertical trends in CO2 and CH4 fluxes along the stems and their low correlation with groundwater levels and soil CO2 and CH4 partial pressures suggest tree internal production as the primary source of stem emissions. At the ecosystem level, the stem CO2, CH4 and N2O emissions represented 52 ± 16 % of the forest floor CO2 emissions and 3 ± 1 % and 11 ± 40 % of the forest floor CH4 and N2O uptake, respectively, during the snow-free period (median ± SE). The six month snow-cover period contributed 11 ± 45 % and 40 ± 29 % to annual stem CO2 and CH4 emissions, respectively. Overall, the stem gas fluxes were more typical for upland rather than wetland ecosystems likely due to historic ditching and subsequent groundwater level decrease.
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Affiliation(s)
- Marcus Klaus
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Skogsmarksgränd 17, 90183 Umeå, Sweden; Global Change Research Institute of the Czech Academy of Sciences, Bělidla 986/4a, 603 00 Brno, Czech Republic.
| | - Mats Öquist
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Skogsmarksgränd 17, 90183 Umeå, Sweden
| | - Kateřina Macháčová
- Global Change Research Institute of the Czech Academy of Sciences, Bělidla 986/4a, 603 00 Brno, Czech Republic
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2
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Dukat P, Hölttä T, Oren R, Salmon Y, Urbaniak M, Vesala T, Aalto J, Lintunen A. Partitioning seasonal stem carbon dioxide efflux into stem respiration, bark photosynthesis, and transport-related flux in Scots pine. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:4944-4959. [PMID: 38779859 PMCID: PMC11350082 DOI: 10.1093/jxb/erae242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Accepted: 05/22/2024] [Indexed: 05/25/2024]
Abstract
Stem CO2 efflux is an important component of the carbon balance in forests. The efflux is considered to principally reflect the net result of two dominating and opposing processes: stem respiration and stem photosynthesis. In addition, transport of CO2 in xylem sap is thought to play an appreciable role in affecting the net flux. This work presents an approach to partition stem CO2 efflux among these processes using sap-flux data and CO2-exchange measurements from dark and transparent chambers placed on mature Scots pine (Pinus sylvestris) trees. Seasonal changes and monthly parameters describing the studied processes were determined. Respiration contributed most to stem net CO2 flux, reaching up to 79% (considering the sum of the absolute values of stem respiration, stem photosynthesis, and flux from CO2 transported in xylem sap to be 100%) in June, when stem growth was greatest. The contribution of photosynthesis accounted for up to 13% of the stem net CO2 flux, increasing over the monitoring period. CO2 transported axially with sap flow decreased towards the end of the growing season. At a reference temperature, respiration decreased starting around midsummer, while its temperature sensitivity increased during the summer. A decline was observed for photosynthetic quantum yield around midsummer together with a decrease in light-saturation point. The proposed approach facilitates modeling net stem CO2 flux at a range of time scales.
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Affiliation(s)
- Paulina Dukat
- Institute for Atmospheric and Earth System Research/Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, Helsinki, Finland
- Laboratory of Meteorology, Department of Construction and Geoengineering, Faculty of Environmental Engineering and Mechanical Engineering, Poznan University of Life Sciences, Piątkowska 94, 60-649 Poznań, Poland
| | - Teemu Hölttä
- Institute for Atmospheric and Earth System Research/Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, Helsinki, Finland
| | - Ram Oren
- Institute for Atmospheric and Earth System Research/Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, Helsinki, Finland
- Nicholas School of the Environment & Pratt School of Engineering, Duke University, Durham NC, USA
| | - Yann Salmon
- Institute for Atmospheric and Earth System Research/Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, Helsinki, Finland
- Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki, Finland
| | - Marek Urbaniak
- Laboratory of Meteorology, Department of Construction and Geoengineering, Faculty of Environmental Engineering and Mechanical Engineering, Poznan University of Life Sciences, Piątkowska 94, 60-649 Poznań, Poland
| | - Timo Vesala
- Institute for Atmospheric and Earth System Research/Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, Helsinki, Finland
- Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki, Finland
| | - Juho Aalto
- Institute for Atmospheric and Earth System Research/Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, Helsinki, Finland
| | - Anna Lintunen
- Institute for Atmospheric and Earth System Research/Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, Helsinki, Finland
- Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki, Finland
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Natale S, Peralta Ogorek LL, Caracciolo L, Morosinotto T, van Amerongen H, Casolo V, Pedersen O, Nardini A. Net O 2 exchange rates under dark and light conditions across different stem compartments. THE NEW PHYTOLOGIST 2024; 243:72-81. [PMID: 38703003 DOI: 10.1111/nph.19782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Accepted: 04/02/2024] [Indexed: 05/06/2024]
Abstract
Woody plants display some photosynthetic activity in stems, but the biological role of stem photosynthesis and the specific contributions of bark and wood to carbon uptake and oxygen evolution remain poorly understood. We aimed to elucidate the functional characteristics of chloroplasts in stems of different ages in Fraxinus ornus. Our investigation employed diverse experimental approaches, including microsensor technology to assess oxygen production rates in whole stem, bark, and wood separately. Additionally, we utilized fluorescence lifetime imaging microscopy (FLIM) to characterize the relative abundance of photosystems I and II (PSI : PSII chlorophyll ratio) in bark and wood. Our findings revealed light-induced increases in O2 production in whole stem, bark, and wood. We present the radial profile of O2 production in F. ornus stems, demonstrating the capability of stem chloroplasts to perform light-dependent electron transport. Younger stems exhibited higher light-induced O2 production and dark respiration rates than older ones. While bark emerged as the primary contributor to net O2 production under light conditions, our data underscored that wood chloroplasts are also photosynthetically active. The FLIM analysis unveiled a lower PSI abundance in wood than in bark, suggesting stem chloroplasts are not only active but also acclimate to the spectral composition of light reaching inner compartments.
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Affiliation(s)
- Sara Natale
- Dipartimento di Scienze della Vita, Università di Trieste, Via L. Giorgieri 10, Trieste, 34127, Italy
- Dipartimento di Biologia, Università di Padova, Via Ugo Bassi 58B, Padova, 35121, Italy
| | - Lucas Léon Peralta Ogorek
- The Freshwater Biological Laboratory, Department of Biology, University of Copenhagen, Universitetsparken 4, Copenhagen, 2100, Denmark
- School of Biosciences, Sutton Bonington Campus, University of Nottingham, Loughborough, LE12 5RD, UK
| | - Ludovico Caracciolo
- Laboratory of Biophysics, Wageningen University & Research, PO Box 8128, 6700 ET, Wageningen, the Netherlands
| | - Tomas Morosinotto
- Dipartimento di Biologia, Università di Padova, Via Ugo Bassi 58B, Padova, 35121, Italy
| | - Herbert van Amerongen
- Laboratory of Biophysics, Wageningen University & Research, PO Box 8128, 6700 ET, Wageningen, the Netherlands
- MicroSpectroscopy Research Facility at Wageningen University & Research, Stippeneng 4, 6708 WE, Wageningen, the Netherlands
| | - Valentino Casolo
- Dipartimento di Scienze Agroalimentari, Ambientali e Animali, Università di Udine, Sezione di Biologia Vegetale, Via delle Scienze 91, Udine, 33100, Italy
| | - Ole Pedersen
- The Freshwater Biological Laboratory, Department of Biology, University of Copenhagen, Universitetsparken 4, Copenhagen, 2100, Denmark
- School of Biological Sciences, The University of Western Australia, Perth, WA, 6009, Australia
| | - Andrea Nardini
- Dipartimento di Scienze della Vita, Università di Trieste, Via L. Giorgieri 10, Trieste, 34127, Italy
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Darenova E, Knott R, Vichta T. Does lower water availability limit stem CO 2 efflux of oak and hornbeam coppices? AOB PLANTS 2024; 16:plae023. [PMID: 38638333 PMCID: PMC11025467 DOI: 10.1093/aobpla/plae023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Accepted: 04/04/2024] [Indexed: 04/20/2024]
Abstract
Recent changes in water availability can be crucial for the development, growth and carbon budget of forests. Therefore, our aim was to determine the effect of reduced throughfall and severe summer drought on stem CO2 efflux as a function of temperature and stem increment. Stem CO2 efflux was measured using the chamber method on oak and hornbeam under four treatments: coppice, thinned coppice, and both coppice and thinned coppice with 30 %-reduced throughfall. The first year of the experiment had favourable soil water availability and the second year was characterized by a dry summer. While reduced throughfall had no effect on stem CO2 efflux, the summer drought decreased efflux by 43-81 % during July and August. The stem CO2 efflux was reduced less severely (by 13-40 %) in September when the drought persisted but the stem increment was already negligible. The stem increment was also strongly affected by the drought, which was reflected in its paired relationship with stem CO2 efflux over the two experimental years. The study showed that summer dry periods significantly and rapidly reduce stem CO2 efflux, whereas a constant 30 % rainfall reduction needs probably a longer time to affect stem properties, and indirectly stem CO2 efflux.
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Affiliation(s)
- Eva Darenova
- Global Change Research Institute of the Czech Academy of Sciences, Belidla 986/4a, 60300 Brno, Czech Republic
- Department of Forest Ecology, Faculty of Forestry and Wood Technology, Mendel University in Brno, Zemedelska 1665/1, Brno 613 00, Czech Republic
| | - Robert Knott
- Department of Silviculture, Faculty of Forestry and Wood Technology, Mendel University in Brno, Zemedelska 1665/1, Brno 613 00, Czech Republic
| | - Tomáš Vichta
- Department of Geology and Soil Science, Faculty of Forestry and Wood Technology, Mendel University in Brno, Zemedelska 1665/1, Brno 613 00, Czech Republic
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Marshall JD, Tarvainen L, Zhao P, Lim H, Wallin G, Näsholm T, Lundmark T, Linder S, Peichl M. Components explain, but do eddy fluxes constrain? Carbon budget of a nitrogen-fertilized boreal Scots pine forest. THE NEW PHYTOLOGIST 2023; 239:2166-2179. [PMID: 37148187 DOI: 10.1111/nph.18939] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2022] [Accepted: 03/22/2023] [Indexed: 05/08/2023]
Abstract
Nitrogen (N) fertilization increases biomass and soil organic carbon (SOC) accumulation in boreal pine forests, but the underlying mechanisms remain uncertain. At two Scots pine sites, one undergoing annual N fertilization and the other a reference, we sought to explain these responses. We measured component fluxes, including biomass production, SOC accumulation, and respiration, and summed them into carbon budgets. We compared the resulting summations to ecosystem fluxes measured by eddy covariance. N fertilization increased most component fluxes (P < 0.05), especially SOC accumulation (20×). Only fine-root, mycorrhiza, and exudate production decreased, by 237 (SD = 28) g C m-2 yr-1 . Stemwood production increases were ascribed to this partitioning shift, gross primary production (GPP), and carbon-use efficiency, in that order. The methods agreed in their estimates of GPP in both stands (P > 0.05), but the components detected an increase in net ecosystem production (NEP) (190 (54) g C m-2 yr-1 ; P < 0.01) that eddy covariance did not (19 (62) g C m-2 yr-1 ; ns). The pairing of plots, the simplicity of the sites, and the strength of response provide a compelling description of N effects on the C budget. However, the disagreement between methods calls for further paired tests of N fertilization effects in simple forest ecosystems.
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Affiliation(s)
- John D Marshall
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), Umeå, SE-901 83, Sweden
- Leibniz-Zentrum für Agrarlandschaftsforschung, Isotopen-Biogeochemie and Gasflüsse, Müncheberg, 15374, Germany
| | - Lasse Tarvainen
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), Umeå, SE-901 83, Sweden
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, SE-405 30, Sweden
| | - Peng Zhao
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), Umeå, SE-901 83, Sweden
| | - Hyungwoo Lim
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), Umeå, SE-901 83, Sweden
- Institute of Ecology and Earth Sciences, University of Tartu, Juhan Liivi 2, Tartu, 50409, Estonia
| | - Göran Wallin
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, SE-405 30, Sweden
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, South Parks Road, Oxford, OX1 3QY, UK
| | - Torgny Näsholm
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), Umeå, SE-901 83, Sweden
| | - Tomas Lundmark
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), Umeå, SE-901 83, Sweden
| | - Sune Linder
- Southern Swedish Forest Research Centre, SLU, PO Box 190, Lomma, SE-234 22, Sweden
| | - Matthias Peichl
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), Umeå, SE-901 83, Sweden
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6
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Ye C, Zeng Q, Hu K, Fang D, Hölscher D, Du H, Shi Y, Zhou Y, Berninger F, Mei T, Zhou G. Partitioning of respired CO 2 in newly sprouted Moso bamboo culms. FRONTIERS IN PLANT SCIENCE 2023; 14:1154232. [PMID: 37152132 PMCID: PMC10158728 DOI: 10.3389/fpls.2023.1154232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Accepted: 03/30/2023] [Indexed: 05/09/2023]
Abstract
Stem respiration (R s) plays a vital role in ecosystem carbon cycling. However, the measured efflux on the stem surface (E s) is not always in situ R s but only part of it. A previously proposed mass balance framework (MBF) attempted to explore the multiple partitioning pathways of R s, including sap-flow-transported and internal storage of R s, in addition to E s. This study proposed stem photosynthesis as an additional partitioning pathway to the MBF. Correspondingly, a double-chamber apparatus was designed and applied on newly sprouted Moso bamboo (Phyllostachys edulis) in leafless and leaved stages. R s of newly sprouted bamboo were twice as high in the leafless stage (7.41 ± 2.66 μmol m-2 s-1) than in the leaved stage (3.47 ± 2.43 μmol m-2 s-1). E s accounted for ~80% of R s, while sap flow may take away ~2% of R s in both leafless and leaved stages. Culm photosynthesis accounted for ~9% and 13% of R s, respectively. Carbon sequestration from culm photosynthesis accounted for approximately 2% of the aboveground bamboo biomass in the leafless stage. High culm photosynthesis but low sap flow during the leafless stage and vice versa during the leaved stage make bamboo an outstanding choice for exploring the MBF.
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Affiliation(s)
- Chongyu Ye
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Lin’an, Zhejiang, China
- Key Laboratory of Carbon Cycling in Forest Ecosystems and Carbon Sequestration of Zhejiang Province, Zhejiang A&F University, Lin’an, Zhejiang, China
- College of Environmental and Resource Sciences, Zhejiang A&F University, Lin’an, Zhejiang, China
| | - Qiangfa Zeng
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Lin’an, Zhejiang, China
- Key Laboratory of Carbon Cycling in Forest Ecosystems and Carbon Sequestration of Zhejiang Province, Zhejiang A&F University, Lin’an, Zhejiang, China
- College of Environmental and Resource Sciences, Zhejiang A&F University, Lin’an, Zhejiang, China
| | - Keda Hu
- College of Environmental and Resource Sciences, Zhejiang A&F University, Lin’an, Zhejiang, China
| | - Dongming Fang
- Jiyang College, Zhejiang A&F University, Zhuji, Zhejiang, China
| | - Dirk Hölscher
- Tropical Silviculture and Forest Ecology, University of Göttingen, Göttingen, Germany
| | - Huaqiang Du
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Lin’an, Zhejiang, China
- Key Laboratory of Carbon Cycling in Forest Ecosystems and Carbon Sequestration of Zhejiang Province, Zhejiang A&F University, Lin’an, Zhejiang, China
- College of Environmental and Resource Sciences, Zhejiang A&F University, Lin’an, Zhejiang, China
| | - Yongjun Shi
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Lin’an, Zhejiang, China
- Key Laboratory of Carbon Cycling in Forest Ecosystems and Carbon Sequestration of Zhejiang Province, Zhejiang A&F University, Lin’an, Zhejiang, China
- College of Environmental and Resource Sciences, Zhejiang A&F University, Lin’an, Zhejiang, China
| | - Yufeng Zhou
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Lin’an, Zhejiang, China
- Key Laboratory of Carbon Cycling in Forest Ecosystems and Carbon Sequestration of Zhejiang Province, Zhejiang A&F University, Lin’an, Zhejiang, China
- College of Environmental and Resource Sciences, Zhejiang A&F University, Lin’an, Zhejiang, China
| | - Frank Berninger
- Department of Environmental and Biological Sciences, University of Eastern Finland, Joensuu, Finland
| | - Tingting Mei
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Lin’an, Zhejiang, China
- Key Laboratory of Carbon Cycling in Forest Ecosystems and Carbon Sequestration of Zhejiang Province, Zhejiang A&F University, Lin’an, Zhejiang, China
- College of Environmental and Resource Sciences, Zhejiang A&F University, Lin’an, Zhejiang, China
- *Correspondence: Tingting Mei, ; Guomo Zhou,
| | - Guomo Zhou
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Lin’an, Zhejiang, China
- Key Laboratory of Carbon Cycling in Forest Ecosystems and Carbon Sequestration of Zhejiang Province, Zhejiang A&F University, Lin’an, Zhejiang, China
- College of Environmental and Resource Sciences, Zhejiang A&F University, Lin’an, Zhejiang, China
- *Correspondence: Tingting Mei, ; Guomo Zhou,
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Tang Y, Schiestl-Aalto P, Saurer M, Sahlstedt E, Kulmala L, Kolari P, Ryhti K, Salmon Y, Jyske T, Ding Y, Bäck J, Rinne-Garmston KT. Tree organ growth and carbon allocation dynamics impact the magnitude and δ13C signal of stem and soil CO2 fluxes. TREE PHYSIOLOGY 2022; 42:2404-2418. [PMID: 35849053 PMCID: PMC10101690 DOI: 10.1093/treephys/tpac079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 06/08/2022] [Accepted: 07/02/2022] [Indexed: 05/14/2023]
Abstract
Incomplete knowledge of carbon (C) allocation dynamics in trees hinders accurate modeling and future predictions of tree growth. We studied C allocation dynamics in a mature Pinus sylvestris L. dominated forest with a novel analytical approach, allowing the first comparison of: (i) magnitude and δ13C of shoot, stem and soil CO2 fluxes (Ashoot, Rstem and Rsoil), (ii) concentration and δ13C of compound-specific and/or bulk non-structural carbohydrates (NSCs) in phloem and roots and (iii) growth of stem and fine roots. Results showed a significant effect of phloem NSC concentrations on tracheid growth, and both variables significantly impacted Rstem. Also, concentrations of root NSCs, especially starch, had a significant effect on fine root growth, although no effect of root NSC concentrations or root growth was detected on Rsoil. Time series analysis between δ13C of Ashoot and δ13C of Rstem or δ13C of Rsoil revealed strengthened C allocation to stem or roots under high C demands. Furthermore, we detected a significant correlation between δ13C of Rstem and δ13C of phloem sucrose and glucose, but not for starch or water-soluble carbohydrates. Our results indicate the need to include C allocation dynamics into tree growth models. We recommend using compound-specific concentration and δ13C analysis to reveal C allocation processes that may not be detected by the conventional approach that utilizes bulk organic matter.
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Affiliation(s)
| | - Pauliina Schiestl-Aalto
- Institute for Atmospheric and Earth System Research
(INAR)/Physics, Faculty of Science, University of
Helsinki, P.O. Box 68, FI-00014 Helsinki, Finland
| | - Matthias Saurer
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape
Research WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
| | - Elina Sahlstedt
- Bioeconomy and Environment Unit, Natural Resources Institute
Finland, Latokartanonkaari 9, FI-00790 Helsinki, Finland
| | - Liisa Kulmala
- Institute for Atmospheric and Earth System Research (INAR)/Forest
Sciences, Faculty of Agriculture and Forestry, University
of Helsinki, P.O. Box 27, FI-00014 Helsinki, Finland
- Finnish Meteorological Institute, P.O. Box 503, FI-00101
Helsinki, Finland
| | - Pasi Kolari
- Institute for Atmospheric and Earth System Research
(INAR)/Physics, Faculty of Science, University of
Helsinki, P.O. Box 68, FI-00014 Helsinki, Finland
| | - Kira Ryhti
- Institute for Atmospheric and Earth System Research (INAR)/Forest
Sciences, Faculty of Agriculture and Forestry, University
of Helsinki, P.O. Box 27, FI-00014 Helsinki, Finland
| | - Yann Salmon
- Institute for Atmospheric and Earth System Research (INAR)/Forest
Sciences, Faculty of Agriculture and Forestry, University
of Helsinki, P.O. Box 27, FI-00014 Helsinki, Finland
- Institute for Atmospheric and Earth System Research
(INAR)/Physics, Faculty of Science, University of
Helsinki, P.O. Box 68, FI-00014 Helsinki, Finland
| | - Tuula Jyske
- Production Systems Unit, Natural Resources Institute Finland,
Tietotie 2, FI-02150 Espoo, Finland
| | - Yiyang Ding
- Department of Forest Sciences, Faculty of Agriculture and
Forestry, University of Helsinki, P.O. Box 27, FI-00014
Helsinki, Finland
| | - Jaana Bäck
- Institute for Atmospheric and Earth System Research (INAR)/Forest
Sciences, Faculty of Agriculture and Forestry, University
of Helsinki, P.O. Box 27, FI-00014 Helsinki, Finland
| | - Katja T Rinne-Garmston
- Bioeconomy and Environment Unit, Natural Resources Institute
Finland, Latokartanonkaari 9, FI-00790 Helsinki, Finland
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8
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Carbon allocation and tree diversity: shifts in autotrophic respiration in tree mixtures compared to monocultures. Biologia (Bratisl) 2022. [DOI: 10.1007/s11756-022-01141-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
AbstractMixed species forests are known to have a higher gross primary productivity (GPP) and net primary productivity (NPP) than forests containing only one single tree species. Trees growing in mixtures are characterized by higher autotrophic respiration (Ra), this results in a lower carbon use efficiency of mixed species forests compared to monocultures. The pathway responsible for the high quantities of carbon lost through respiratory pathways is still unclear. Here, we present the only existing measurements evaluating tree mixture effects based on stem CO2 efflux (Estem), scaled to woody respiration (Rw) on stand level. We conducted predawn Estem measurements on five tree species in an experimental tree plantation in Central Panama. Estem was scaled to the entire plot level woody respiration (Rw). Annual Rw was on average 0.25 ± 0.08 Mg C ha− 1 in the monocultures and 0.28 ± 0.10 Mg C ha− 1 in mixed species stands. In mixtures, annual Ra was more than three times higher than in monocultures. As mean Rw was almost constant across the mixture types and Ra varied largely, leads to the conclusion that mixed species plots allocate a higher amount of carbon toward respiratory processes in leaves and roots. This was supported by no significant differences in the mixture effects on the growth respiration relationship.
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Wilkinson SW, Dalen LS, Skrautvol TO, Ton J, Krokene P, Mageroy MH. Transcriptomic changes during the establishment of long-term methyl jasmonate-induced resistance in Norway spruce. PLANT, CELL & ENVIRONMENT 2022; 45:1891-1913. [PMID: 35348221 PMCID: PMC9321552 DOI: 10.1111/pce.14320] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 03/15/2022] [Indexed: 06/14/2023]
Abstract
Norway spruce (Picea abies) is an economically and ecologically important tree species that grows across northern and central Europe. Treating Norway spruce with jasmonate has long-lasting beneficial effects on tree resistance to damaging pests, such as the European spruce bark beetle Ips typographus and its fungal associates. The (epi)genetic mechanisms involved in such long-lasting jasmonate induced resistance (IR) have gained much recent interest but remain largely unknown. In this study, we treated 2-year-old spruce seedlings with methyl jasmonate (MeJA) and challenged them with the I. typographus vectored necrotrophic fungus Grosmannia penicillata. MeJA treatment reduced the extent of necrotic lesions in the bark 8 weeks after infection and thus elicited long-term IR against the fungus. The transcriptional response of spruce bark to MeJA treatment was analysed over a 4-week time course using mRNA-seq. This analysis provided evidence that MeJA treatment induced a transient upregulation of jasmonic acid, salicylic acid and ethylene biosynthesis genes and downstream signalling genes. Our data also suggests that defence-related genes are induced while genes related to growth are repressed by methyl jasmonate treatment. These results provide new clues about the potential underpinning mechanisms and costs associated with long-term MeJA-IR in Norway spruce.
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Affiliation(s)
- Samuel W. Wilkinson
- Plants, Photosynthesis and Soil, School of Biosciences, Institute for Sustainable FoodUniversity of SheffieldSheffieldUK
- Division for Biotechnology and Plant HealthNorwegian Institute of Bioeconomy ResearchÅsNorway
| | - Lars S. Dalen
- Department of CommunicationsNorwegian Institute of Bioeconomy ResearchÅsNorway
| | - Thomas O. Skrautvol
- Division for Biotechnology and Plant HealthNorwegian Institute of Bioeconomy ResearchÅsNorway
- Faculty of Environmental Sciences and Natural Resource ManagementNorwegian University of Life SciencesÅsNorway
| | - Jurriaan Ton
- Plants, Photosynthesis and Soil, School of Biosciences, Institute for Sustainable FoodUniversity of SheffieldSheffieldUK
| | - Paal Krokene
- Division for Biotechnology and Plant HealthNorwegian Institute of Bioeconomy ResearchÅsNorway
| | - Melissa H. Mageroy
- Division for Biotechnology and Plant HealthNorwegian Institute of Bioeconomy ResearchÅsNorway
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10
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Liu R, Feng X, Li C, Ma J, Wang Y, Li Y. The Importance of Stem Photosynthesis for Two Desert Shrubs Across Different Groundwater Depths. FRONTIERS IN PLANT SCIENCE 2022; 13:804786. [PMID: 35371182 PMCID: PMC8965657 DOI: 10.3389/fpls.2022.804786] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 02/10/2022] [Indexed: 06/01/2023]
Abstract
Water availability could alter multiple ecophysiological processes such as water use strategy, photosynthesis, and respiration, thereby modifying plant water use and carbon gain. However, a lack of field observations hinders our understanding of how water availability affects stem photosynthesis at both organ and plant levels of desert shrubs. In this study, we measured gas exchange and oxygen stable isotopes to quantify water sources, stem recycling photosynthesis, and whole-plant carbon balance in two coexisting Haloxylon species (Haloxylon ammodendron and Haloxylon persicum) at different groundwater depths in the Gurbantonggut Desert. The overall aim of the study was to analyze and quantify the important role of stem recycling photosynthesis for desert shrubs (Haloxylon species) under different groundwater depths. The results showed that (1) regardless of changes in groundwater depth, H. ammodendron consistently used groundwater and H. persicum used deep soil water as their main water source, with greater than 75% of xylem water being derived from groundwater and deep soil water for the two species, respectively; (2) stem recycling photosynthesis refixed 72-81% of the stem dark respiration, and its contribution to whole-plant carbon assimilation was 10-21% for the two species; and (3) deepened groundwater increased stem water use efficiency and its contribution to whole-plant carbon assimilation in H. persicum but not in H. ammodendron. Our study provided observational evidence that deepened groundwater depth induced H. persicum to increase stem recycling photosynthetic capacity and a greater contribution to whole-plant carbon assimilation, but this did not occur on H. ammodendron. Our study indicates that stem recycling photosynthesis may play an important role in the survival of desert shrubs in drought conditions.
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Affiliation(s)
- Ran Liu
- State Key Lab of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China
- Fukang National Station of Observation and Research for Desert Ecosystem, Xinjiang, China
| | - Xiaolong Feng
- State Key Lab of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China
- Fukang National Station of Observation and Research for Desert Ecosystem, Xinjiang, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Congjuan Li
- Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China
| | - Jie Ma
- State Key Lab of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China
- Fukang National Station of Observation and Research for Desert Ecosystem, Xinjiang, China
| | - Yugang Wang
- State Key Lab of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China
- Fukang National Station of Observation and Research for Desert Ecosystem, Xinjiang, China
| | - Yan Li
- State Key Lab of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China
- Fukang National Station of Observation and Research for Desert Ecosystem, Xinjiang, China
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11
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Helm J, Hartmann H, Göbel M, Hilman B, Herrera Ramírez D, Muhr J. Low-cost chamber design for simultaneous CO2 and O2 flux measurements between tree stems and the atmosphere. TREE PHYSIOLOGY 2021; 41:1767-1780. [PMID: 33677590 PMCID: PMC8441941 DOI: 10.1093/treephys/tpab022] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 02/02/2021] [Indexed: 05/24/2023]
Abstract
Tree stem CO2 efflux is an important component of ecosystem carbon fluxes and has been the focus of many studies. While CO2 efflux can easily be measured, a growing number of studies have shown that it is not identical with actual in situ respiration. Complementing measurements of CO2 flux with simultaneous measurements of O2 flux provides an additional proxy for respiration, and the combination of both fluxes can potentially help getting closer to actual measures of respiratory fluxes. To date, however, the technical challenge to measure relatively small changes in O2 concentration against its high atmospheric background has prevented routine O2 measurements in field applications. Here, we present a new and low-cost field-tested device for autonomous real-time and quasi-continuous long-term measurements of stem respiration by combining CO2 (NDIR-based) and O2 (quenching-based) sensors in a tree stem chamber. Our device operates as a cyclic-closed system and measures changes in both CO2 and O2 concentration within the chamber over time. The device is battery powered with a >1-week power independence, and data acquisition is conveniently achieved by an internal logger. Results from both field and laboratory tests document that our sensors provide reproducible measurements of CO2 and O2 exchange fluxes under varying environmental conditions.
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Affiliation(s)
| | - Henrik Hartmann
- Max-Planck-Institute for Biogeochemistry, Department of Biogeochemical Processes, Hans-Knöll-Str. 10, 07743 Jena, Germany
| | - Martin Göbel
- Max-Planck-Institute for Biogeochemistry, Department of Biogeochemical Processes, Hans-Knöll-Str. 10, 07743 Jena, Germany
| | - Boaz Hilman
- Max-Planck-Institute for Biogeochemistry, Department of Biogeochemical Processes, Hans-Knöll-Str. 10, 07743 Jena, Germany
| | - David Herrera Ramírez
- Max-Planck-Institute for Biogeochemistry, Department of Biogeochemical Processes, Hans-Knöll-Str. 10, 07743 Jena, Germany
| | - Jan Muhr
- Max-Planck-Institute for Biogeochemistry, Department of Biogeochemical Processes, Hans-Knöll-Str. 10, 07743 Jena, Germany
- Georg-August University Göttingen, Department of Bioclimatology, Büsgenweg 2, 37077 Göttingen, Germany
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12
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Zheng J, Zhang TJ, Li BH, Liang WJ, Zhang QL, Cai ML, Peng CL. Strong Response of Stem Photosynthesis to Defoliation in Mikania micrantha Highlights the Contribution of Phenotypic Plasticity to Plant Invasiveness. FRONTIERS IN PLANT SCIENCE 2021; 12:638796. [PMID: 34025690 PMCID: PMC8131553 DOI: 10.3389/fpls.2021.638796] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 04/13/2021] [Indexed: 06/12/2023]
Abstract
Phenotypic plasticity affords invasive plant species the ability to colonize a wide range of habitats, but physiological plasticity of their stems is seldom recognized. Investigation of the stem plasticity of invasive plant species could lead to a better understanding of their invasiveness. We performed pot experiments involving defoliation treatments and isolated culture experiments to determine whether the invasive species Mikania micrantha exhibits greater plasticity in the stems than do three non-invasive species that co-occur in southern China and then explored the mechanism underlying the modification of its stem photosynthesis. Our results showed that the stems of M. micrantha exhibited higher plasticity in terms of either net or gross photosynthetic rate in response to the defoliation treatment. These effects were positively related to an increased stem elongation rate. The enhancement of stem photosynthesis in M. micrantha resulted from the comprehensive action involving increases in the Chl a/b ratio, D1 protein and stomatal aperture, changes in chloroplast morphology and a decrease in anthocyanins. Increased plasticity of stem photosynthesis may improve the survival of M. micrantha under harsh conditions and allow it to rapidly recover from defoliation injuries. Our results highlight that phenotypic plasticity promotes the invasion success of alien plant invaders.
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Affiliation(s)
- Jin Zheng
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, Guangzhou Key Laboratory of Subtropical Biodiversity and Biomonitoring, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Tai-Jie Zhang
- Guangdong Provincial Key Laboratory of High Technology for Plant Protection, Institute of Plant Protection, Guangdong Academy of Agricultural Sciences, Guangzhou, China
| | - Bo-Hui Li
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, Guangzhou Key Laboratory of Subtropical Biodiversity and Biomonitoring, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Wei-Jie Liang
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, Guangzhou Key Laboratory of Subtropical Biodiversity and Biomonitoring, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Qi-Lei Zhang
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, Guangzhou Key Laboratory of Subtropical Biodiversity and Biomonitoring, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Min-Ling Cai
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, Guangzhou Key Laboratory of Subtropical Biodiversity and Biomonitoring, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Chang-Lian Peng
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, Guangzhou Key Laboratory of Subtropical Biodiversity and Biomonitoring, School of Life Sciences, South China Normal University, Guangzhou, China
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13
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Schiestl‐Aalto P, Stangl ZR, Tarvainen L, Wallin G, Marshall J, Mäkelä A. Linking canopy-scale mesophyll conductance and phloem sugar δ 13 C using empirical and modelling approaches. THE NEW PHYTOLOGIST 2021; 229:3141-3155. [PMID: 33222199 PMCID: PMC7986199 DOI: 10.1111/nph.17094] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Accepted: 11/16/2020] [Indexed: 05/26/2023]
Abstract
Interpreting phloem carbohydrate or xylem tissue carbon isotopic composition as measures of water-use efficiency or past tree productivity requires in-depth knowledge of the factors altering the isotopic composition within the pathway from ambient air to phloem contents and tree ring. One of least understood of these factors is mesophyll conductance (gm ). We formulated a dynamic model describing the leaf photosynthetic pathway including seven alternative gm descriptions and a simple transport of sugars from foliage down the trunk. We parameterised the model for a boreal Scots pine stand and compared simulated gm responses with weather variations. We further compared the simulated δ13 C of new photosynthates among the different gm descriptions and against measured phloem sugar δ13 C. Simulated gm estimates of the seven descriptions varied according to weather conditions, resulting in varying estimates of phloem δ13 C during cold/moist and warm/dry periods. The model succeeded in predicting a drought response and a postdrought release in phloem sugar δ13 C indicating suitability of the model for inverse prediction of leaf processes from phloem isotopic composition. We suggest short-interval phloem sampling during and after extreme weather conditions to distinguish between mesophyll conductance drivers for future model development.
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Affiliation(s)
- Pauliina Schiestl‐Aalto
- Institute for Atmospheric and Earth System Research (INAR)/Forest SciencesHelsinki00014Finland
- Department of Forest Ecology and ManagementSLUUmeå901 83Sweden
| | | | - Lasse Tarvainen
- Department of Biological and Environmental SciencesUniversity of GothenburgGothenburg405 30Sweden
| | - Göran Wallin
- Department of Biological and Environmental SciencesUniversity of GothenburgGothenburg405 30Sweden
| | - John Marshall
- Department of Forest Ecology and ManagementSLUUmeå901 83Sweden
| | - Annikki Mäkelä
- Institute for Atmospheric and Earth System Research (INAR)/Forest SciencesHelsinki00014Finland
- Department of Forest Ecology and ManagementSLUUmeå901 83Sweden
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14
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Tarvainen L, Wallin G, Linder S, Näsholm T, Oren R, Ottosson Löfvenius M, Räntfors M, Tor-Ngern P, Marshall JD. Limited vertical CO2 transport in stems of mature boreal Pinus sylvestris trees. TREE PHYSIOLOGY 2021; 41:63-75. [PMID: 32864696 DOI: 10.1093/treephys/tpaa113] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 08/25/2020] [Indexed: 05/14/2023]
Abstract
Several studies have suggested that CO2 transport in the transpiration stream can considerably bias estimates of root and stem respiration in ring-porous and diffuse-porous tree species. Whether this also happens in species with tracheid xylem anatomy and lower sap flow rates, such as conifers, is currently unclear. We infused 13C-labelled solution into the xylem near the base of two 90-year-old Pinus sylvestris L. trees. A custom-built gas exchange system and an online isotopic analyser were used to sample the CO2 efflux and its isotopic composition continuously from four positions along the bole and one upper canopy shoot in each tree. Phloem and needle tissue 13C enrichment was also evaluated at these positions. Most of the 13C label was lost by diffusion within a few metres of the infusion point indicating rapid CO2 loss during vertical xylem transport. No 13C enrichment was detected in the upper bole needle tissues. Furthermore, mass balance calculations showed that c. 97% of the locally respired CO2 diffused radially to the atmosphere. Our results support the notion that xylem CO2 transport is of limited magnitude in conifers. This implies that the concerns that stem transport of CO2 derived from root respiration biases chamber-based estimates of forest carbon cycling may be unwarranted for mature conifer stands.
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Affiliation(s)
- Lasse Tarvainen
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), Skogmarksgränd, SE-901 83 Umeå, Sweden
- Department of Biological and Environmental Sciences, University of Gothenburg, Carl Skottsbergs gata 22B, SE-405 30 Gothenburg, Sweden
- Umeå Plant Science Centre, Department of Plant Physiology, Umeå University, Linnaeus väg 6, SE-901 87 Umeå, Sweden
| | - Göran Wallin
- Department of Biological and Environmental Sciences, University of Gothenburg, Carl Skottsbergs gata 22B, SE-405 30 Gothenburg, Sweden
| | - Sune Linder
- Southern Swedish Forest Research Centre, SLU, PO Box 49, SE-230 53, Alnarp, Sweden
| | - Torgny Näsholm
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), Skogmarksgränd, SE-901 83 Umeå, Sweden
| | - Ram Oren
- Nicholas School of the Environment, Duke University, Grainger Hall, 9 Circuit Drive, Box 90328, Durham, NC 27708-0328, USA
- Pratt School of Engineering, Duke University, 305 Teer Building, Box 90271, Durham, NC 27708-0271, USA
- Department of Forest Sciences, University of Helsinki, Latokartanonkaari 7, Box 27, FI-00014 Helsinki, Finland
| | - Mikaell Ottosson Löfvenius
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), Skogmarksgränd, SE-901 83 Umeå, Sweden
| | - Mats Räntfors
- Department of Biological and Environmental Sciences, University of Gothenburg, Carl Skottsbergs gata 22B, SE-405 30 Gothenburg, Sweden
| | - Pantana Tor-Ngern
- Department of Environmental Science, Faculty of Science, Chulalongkorn University, 254 Phayathai Rd, Wang Mai, Pathum Wan District, 10330 Bangkok, Thailand
- Environment, Health and Social Data Analytics Research Group, Chulalongkorn University, 254 Phayathai Rd, Wang Mai, Pathum Wan District, 10330 Bangkok, Thailand
| | - John D Marshall
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), Skogmarksgränd, SE-901 83 Umeå, Sweden
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15
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De Roo L, Lauriks F, Salomón RL, Oleksyn J, Steppe K. Woody tissue photosynthesis increases radial stem growth of young poplar trees under ambient atmospheric CO2 but its contribution ceases under elevated CO2. TREE PHYSIOLOGY 2020; 40:1572-1582. [PMID: 32597984 DOI: 10.1093/treephys/tpaa085] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 06/19/2020] [Accepted: 06/22/2020] [Indexed: 06/11/2023]
Abstract
Woody tissue photosynthesis (Pwt) contributes to the tree carbon (C) budget and generally stimulates radial stem growth under ambient atmospheric CO2 concentration (aCO2). Moreover, Pwt has potential to enhance tree survival under changing climates by delaying negative effects of drought stress on tree hydraulic functioning. However, the relevance of Pwt on tree performance under elevated atmospheric CO2 concentration (eCO2) remains unexplored. To fill this knowledge gap, 1-year-old Populus tremula L. seedlings were grown in two treatment chambers at aCO2 and eCO2 (400 and 660 ppm, respectively), and woody tissues of half of the seedlings in each treatment chamber were light-excluded to prevent Pwt. Radial stem growth, sap flow, leaf photosynthesis and stomatal and canopy conductance were measured throughout the growing season, and the concentration of non-structural carbohydrates (NSC) in stem tissues was determined at the end of the experiment. Fuelled by eCO2, an increase in stem growth of 18 and 50% was observed in control and light-excluded trees, respectively. Woody tissue photosynthesis increased radial stem growth by 39% under aCO2, while, surprisingly, no impact of Pwt on stem growth was observed under eCO2. By the end of the growing season, eCO2 and Pwt had little effect on stem growth, leaf photosynthesis acclimated to eCO2, but stomatal conductance did not, and homeostatic stem NSC pools were observed among combined treatments. Our results highlight that eCO2 potentially fulfils plant C requirements, limiting the contribution of Pwt to stem growth as atmospheric [CO2] rises, and that radial stem growth in young developing trees was C (source) limited during early phenological stages but transitioned towards sink-driven control at the end of the growing season.
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Affiliation(s)
- Linus De Roo
- Laboratory of Plant Ecology, Department of Plant and Crops Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000 Ghent, Belgium
| | - Fran Lauriks
- Laboratory of Plant Ecology, Department of Plant and Crops Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000 Ghent, Belgium
| | - Roberto Luis Salomón
- Laboratory of Plant Ecology, Department of Plant and Crops Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000 Ghent, Belgium
| | - Jacek Oleksyn
- Polish Academy of Sciences, Institute of Dendrology, Parkowa 5, 62-035 Kórnik, Poland
| | - Kathy Steppe
- Laboratory of Plant Ecology, Department of Plant and Crops Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000 Ghent, Belgium
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16
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De Roo L, Salomón RL, Oleksyn J, Steppe K. Woody tissue photosynthesis delays drought stress in Populus tremula trees and maintains starch reserves in branch xylem tissues. THE NEW PHYTOLOGIST 2020; 228:70-81. [PMID: 32416019 DOI: 10.1111/nph.16662] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Accepted: 05/04/2020] [Indexed: 06/11/2023]
Abstract
Photosynthesis in woody tissues (Pwt ) is less sensitive to water shortage than in leaves, hence, Pwt might be a crucial carbon source to alleviate drought stress. To evaluate the impact of Pwt on tree drought tolerance, woody tissues of 4-m-tall drought-stressed Populus tremula trees were subjected to a light-exclusion treatment across the entire plant to inhibit Pwt . Xylem water potential (Ψxylem ), sap flow ( FH2O ), leaf net photosynthesis (Pn,l ), stem diameter variations (ΔD), in vivo acoustic emissions in stems (AEs) and nonstructural carbohydrate concentrations ([NSC]) were monitored to comprehensively assess water and carbon relations at whole-tree level. Under well-watered conditions, Pwt kept Ψxylem at a higher level, lowered FH2O and had no effect on [NSC]. Under drought, Ψxylem , FH2O and Pn,l in light-excluded trees rapidly decreased in concert with reductions in branch xylem starch concentration. Moreover, sub-daily patterns of ΔD, FH2O and AEs were strongly related, suggesting that in vivo AEs may inform not only about embolism events, but also about capacitive release and replenishment of stem water pools. Results highlight the importance of Pwt in maintaining xylem hydraulic integrity under drought conditions and in sustaining NSC pools to potentially limit increases in xylem tension.
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Affiliation(s)
- Linus De Roo
- Laboratory of Plant Ecology, Faculty of Bioscience Engineering, Ghent University, B-9000, Ghent, Belgium
| | - Roberto Luis Salomón
- Laboratory of Plant Ecology, Faculty of Bioscience Engineering, Ghent University, B-9000, Ghent, Belgium
| | - Jacek Oleksyn
- Institute of Dendrology, Polish Academy of Sciences, Parkowa 5, PL-62-035, Kórnik, Poland
| | - Kathy Steppe
- Laboratory of Plant Ecology, Faculty of Bioscience Engineering, Ghent University, B-9000, Ghent, Belgium
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17
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De Roo L, Salomón RL, Steppe K. Woody tissue photosynthesis reduces stem CO 2 efflux by half and remains unaffected by drought stress in young Populus tremula trees. PLANT, CELL & ENVIRONMENT 2020; 43:981-991. [PMID: 31884680 DOI: 10.1111/pce.13711] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 12/19/2019] [Accepted: 12/21/2019] [Indexed: 06/10/2023]
Abstract
A substantial portion of locally respired CO2 in stems can be assimilated by chloroplast-containing tissues. Woody tissue photosynthesis (Pwt ) therefore plays a major role in the stem carbon balance. To study the impact of Pwt on stem carbon cycling along a gradient of water availability, stem CO2 efflux (EA ), xylem CO2 concentration ([CO2 ]), and xylem water potential (Ψxylem ) were measured in 4-year-old Populus tremula L. trees exposed to drought stress and different regimes of light exclusion of woody tissues. Under well-watered conditions, local Pwt decreased EA up to 30%. Axial CO2 diffusion (Dax ) induced by distant Pwt caused an additional decrease in EA of up to 25% and limited xylem [CO2 ] build-up. Under drought stress, absolute decreases in EA driven by Pwt remained stable, denoting that Pwt was not affected by drought. At the end of the dry period, when transpiration was low, local Pwt and Dax offset 20% and 10% of stem respiration on a daily basis, respectively. These results highlight (a) the importance of Pwt for an adequate interpretation of EA measurements and (b) homeostatic Pwt along a drought stress gradient, which might play a crucial role to fuel stem metabolism when leaf carbon uptake and phloem transport are limited.
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Affiliation(s)
- Linus De Roo
- Laboratory of Plant Ecology, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Roberto Luis Salomón
- Laboratory of Plant Ecology, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Kathy Steppe
- Laboratory of Plant Ecology, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
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18
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Marler TE, Lindström AJ. Diel patterns of stem CO 2 efflux vary among cycads, arborescent monocots, and woody eudicots and gymnosperms. PLANT SIGNALING & BEHAVIOR 2020; 15:1732661. [PMID: 32100615 PMCID: PMC7194385 DOI: 10.1080/15592324.2020.1732661] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2020] [Revised: 02/13/2020] [Accepted: 02/15/2020] [Indexed: 05/28/2023]
Abstract
The diel patterns of stem carbon dioxide efflux (Es) were determined for cycads, monocots, and woody eudicot and gymnosperm tree species. Stem Es at a height of 30-40 cm was measured every 2 h throughout 31-h campaigns. Our range of Es was 1.5-4.0 µmol·m-2·s-1 for cycads, 1.0-3.5 µmol·m-2·s-1 for arborescent monocots, and 1.5-4.5 µmol·m-2·s-1 for woody eudicot and gymnosperm trees species. Time of day did not influence Es of cycads or monocots. In contrast, the woody stems of eudicots and gymnosperms exhibited diurnal Es that was 36% to 40% greater than nocturnal Es. The established literature based on Es of woody tree species cannot be used to estimate habitat carbon cycles in habitats which contain cycad or monocot trees. Time of day must be included for accuracy of research on Es of woody tree species. Failures to account for the spatiotemporal differences of Es may explain some of the disparity in outcomes of published stem respiration studies.
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Affiliation(s)
- Thomas E. Marler
- College of Natural and Applied Sciences, University of Guam, Mangilao, Guam, USA
| | - Anders J. Lindström
- Plant Collections Department, Nong Nooch Tropical Botanical Garden, Sattahip, Thailand
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19
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Marler TE, Krishnapillai MV. Vertical Strata and Stem Carbon Dioxide Efflux in Cycas Trees. PLANTS (BASEL, SWITZERLAND) 2020; 9:E230. [PMID: 32054006 PMCID: PMC7076351 DOI: 10.3390/plants9020230] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/05/2020] [Revised: 02/02/2020] [Accepted: 02/09/2020] [Indexed: 11/16/2022]
Abstract
Stem respiration is influenced by the vertical location of tree stems, but the influence of vertical location on stem respiration in a representative cycad species has not been determined. We quantified the influence of vertical strata on stem carbon dioxide efflux (Es) for six arborescent Cycas L. species to characterize this component of stem respiration and ecosystem carbon cycling. The influence of strata on Es was remarkably consistent among the species, with a stable baseline flux characterizing the full mid-strata of the pachycaulous stems and an increase in Es at the lowest and highest strata. The mid-strata flux ranged from 1.8 µmol·m-2·s-1 for Cycas micronesica K.D. Hill to 3.5 µmol·m-2·s-1 for Cycas revoluta Thunb. For all species, Es increased about 30% at the lowest stratum and about 80% at the highest stratum. A significant quadratic model adequately described the Es patterns for all six species. The increase of Es at the lowest stratum was consistent with the influence of root-respired carbon dioxide entering the stem via sap flow, then contributing to Es via radial conductance to the stem surface. The substantial increase in Es at the highest stratum is likely a result of the growth and maintenance respiration of the massive cycad primary thickening meristem that constructs the unique pachycaulous cycad stem.
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Affiliation(s)
- Thomas E. Marler
- College of Natural and Applied Sciences, University of Guam, Mangilao, Guam 96923, USA
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20
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Stangl ZR, Tarvainen L, Wallin G, Ubierna N, Räntfors M, Marshall JD. Diurnal variation in mesophyll conductance and its influence on modelled water-use efficiency in a mature boreal Pinus sylvestris stand. PHOTOSYNTHESIS RESEARCH 2019; 141:53-63. [PMID: 31123952 PMCID: PMC6612512 DOI: 10.1007/s11120-019-00645-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Accepted: 05/06/2019] [Indexed: 05/02/2023]
Abstract
Mesophyll conductance (gm) is a critical variable for the use of stable carbon isotopes to infer photosynthetic water-use efficiency (WUE). Although gm is similar in magnitude to stomatal conductance (gs), it has been measured less often, especially under field conditions and at high temporal resolution. We mounted an isotopic CO2 analyser on a field photosynthetic gas exchange system to make continuous online measurements of gas exchange and photosynthetic 13C discrimination (Δ13C) on mature Pinus sylvestris trees. This allowed the calculation of gm, gs, net photosynthesis (Anet), and WUE. These measurements highlighted the asynchronous diurnal behaviour of gm and gs. While gs declined from around 10:00, Anet declined first after 12:00, and gm remained near its maximum until 16:00. We suggest that high gm played a role in supporting an extended Anet peak despite stomatal closure. Comparing three models to estimate WUE from ∆13C, we found that a simple model, assuming constant net fractionation during carboxylation (27‰), predicted WUE well, but only for about 75% of the day. A more comprehensive model, accounting explicitly for gm and the effects of daytime respiration and photorespiration, gave reliable estimates of WUE, even in the early morning hours when WUE was more variable. Considering constant, finite gm or gm/gs yielded similar WUE estimates on the diurnal scale, while assuming infinite gm led to overestimation of WUE. These results highlight the potential of high-resolution gm measurements to improve modelling of Anet and WUE and demonstrate that such gm data can be acquired, even under field conditions.
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Affiliation(s)
- Zsofia R Stangl
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - Lasse Tarvainen
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå, Sweden
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Göran Wallin
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Nerea Ubierna
- Research School of Biology, The Australian National University, Canberra, ACT, Australia
| | - Mats Räntfors
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
| | - John D Marshall
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå, Sweden.
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Stem Photosynthesis of Twig and Its Contribution to New Organ Development in Cutting Seedlings of Salix Matsudana Koidz. FORESTS 2018. [DOI: 10.3390/f9040207] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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