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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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2
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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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Rademacher T, Fonti P, LeMoine JM, Fonti MV, Bowles F, Chen Y, Eckes-Shephard AH, Friend AD, Richardson AD. Insights into source/sink controls on wood formation and photosynthesis from a stem chilling experiment in mature red maple. THE NEW PHYTOLOGIST 2022; 236:1296-1309. [PMID: 35927942 DOI: 10.1111/nph.18421] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 07/30/2022] [Indexed: 06/15/2023]
Abstract
Whether sources or sinks control wood growth remains debated with a paucity of evidence from mature trees in natural settings. Here, we altered carbon supply rate in stems of mature red maples (Acer rubrum) within the growing season by restricting phloem transport using stem chilling; thereby increasing carbon supply above and decreasing carbon supply below the restrictions, respectively. Chilling successfully altered nonstructural carbon (NSC) concentrations in the phloem without detectable repercussions on bulk NSC in stems and roots. Ring width responded strongly to local variations in carbon supply with up to seven-fold differences along the stem of chilled trees; however, concurrent changes in the structural carbon were inconclusive at high carbon supply due to large local variability of wood growth. Above chilling-induced bottlenecks, we also observed higher leaf NSC concentrations, reduced photosynthetic capacity, and earlier leaf coloration and fall. Our results indicate that the cambial sink is affected by carbon supply, but within-tree feedbacks can downregulate source activity, when carbon supply exceeds demand. Such feedbacks have only been hypothesized in mature trees. Consequently, these findings constitute an important advance in understanding source-sink dynamics, suggesting that mature red maples operate close to both source- and sink-limitation in the early growing season.
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Affiliation(s)
- Tim Rademacher
- Harvard Forest, Harvard University, Petersham, MA, 01366, USA
- School of Informatics, Computing and Cyber Systems and Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ, 86011, USA
- Institut des Sciences de la Forêt Tempérée, Université du Québec en Outaouais, Ripon, J0V 1V0, QC, Canada
| | - Patrick Fonti
- Swiss Federal Research Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, 8903, Switzerland
| | - James M LeMoine
- School of Informatics, Computing and Cyber Systems and Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ, 86011, USA
| | - Marina V Fonti
- Swiss Federal Research Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, 8903, Switzerland
- Institute of Ecology and Geography, Siberian Federal University, Krasnoyarsk, 660041, Russia
| | | | - Yizhao Chen
- Department of Geography, University of Cambridge, Cambridge, CB2 1BY, UK
| | - Annemarie H Eckes-Shephard
- Department of Geography, University of Cambridge, Cambridge, CB2 1BY, UK
- Department of Physical Geography and Ecosystem Science, Lund University, Lund, 223 62, Sweden
| | - Andrew D Friend
- Department of Geography, University of Cambridge, Cambridge, CB2 1BY, UK
| | - Andrew D Richardson
- School of Informatics, Computing and Cyber Systems and Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ, 86011, USA
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Changes in the Differentiation Program of Birch Cambial Derivatives following Trunk Girdling. FORESTS 2022. [DOI: 10.3390/f13081171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
The mechanisms regulating the tree trunk radial growth can be studied in original experiments. One technique for studying cambium activity (the meristem involved in radial growth) under conditions of an increased photoassimilate level is trunk girdling. We girdled the trunks of 17- to 22-year-old silver birch plants (Betula pendula Roth var. pendula) during the active growth period and collected xylem and phloem samples at two height levels (1 cm and 35 cm) above girdle, 10, 20, and 30 days after girdling. We investigated the changes that occurred at the anatomical level, as well as the activities of sucrose-metabolizing enzymes and antioxidant-system enzymes and the expression of genes that encode proteins involved in sucrose and auxin transport and metabolism. A moderate increase in photoassimilates (35 cm above the girdle) resulted in a change in the ratio of phloem to xylem increments and an increase in the proportion of parenchyma in the conducting tissues. The increase of photoassimilates above the level at which they can be used in the processes of normal tissue growth and development (1 cm above the girdle) led to xylogenesis suppression and the stimulation of phloem formation, a significant increase in the parenchyma proportion in the conducting tissues, and formation of large sclereid complexes. The differentiation of parenchyma and sclereid cells coincided with biochemical and molecular markers of abnormal conducting tissue formation in Karelian birch, which are also characterized by high proportions of parenchyma and sclereid near the cambium. The results obtained are important in understanding the cambium responses to the photoassimilate distribution changes and estimating tree productivity and survival under changing environmental conditions.
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Rademacher T, Fonti P, LeMoine JM, Fonti MV, Basler D, Chen Y, Friend AD, Seyednasrollah B, Eckes-Shephard AH, Richardson AD. Manipulating phloem transport affects wood formation but not local nonstructural carbon reserves in an evergreen conifer. PLANT, CELL & ENVIRONMENT 2021; 44:2506-2521. [PMID: 34043242 DOI: 10.1111/pce.14117] [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: 01/23/2021] [Revised: 05/16/2021] [Accepted: 05/18/2021] [Indexed: 06/12/2023]
Abstract
How variations in carbon supply affect wood formation remains poorly understood in particular in mature forest trees. To elucidate how carbon supply affects carbon allocation and wood formation, we attempted to manipulate carbon supply to the cambial region by phloem girdling and compression during the mid- and late-growing season and measured effects on structural development, CO2 efflux and nonstructural carbon reserves in stems of mature white pines. Wood formation and stem CO2 efflux varied with a location relative to treatment (i.e., above or below the restriction). We observed up to twice as many tracheids formed above versus below the treatment after the phloem transport manipulation, whereas the cell-wall area decreased only slightly below the treatments, and cell size did not change relative to the control. Nonstructural carbon reserves in the xylem, needles and roots were largely unaffected by the treatments. Our results suggest that low and high carbon supply affects wood formation, primarily through a strong effect on cell proliferation, and respiration, but local nonstructural carbon concentrations appear to be maintained homeostatically. This contrasts with reports of decoupling of source activity and wood formation at the whole-tree or ecosystem level, highlighting the need to better understand organ-specific responses, within-tree feedbacks, as well as phenological and ontogenetic effects on sink-source dynamics.
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Affiliation(s)
- Tim Rademacher
- School of Informatics, Computing, and Cyber Security, Northern Arizona University, Flagstaff, Arizona, USA
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts, USA
| | - Patrick Fonti
- Swiss Federal Research Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - James M LeMoine
- School of Informatics, Computing, and Cyber Security, Northern Arizona University, Flagstaff, Arizona, USA
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
| | - Marina V Fonti
- Swiss Federal Research Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
- Institute of Ecology and Geography, Siberian Federal University, Krasnoyarsk, Russian Federation
| | - David Basler
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts, USA
| | - Yizhao Chen
- Department of Geography, University of Cambridge, Cambridge, UK
| | - Andrew D Friend
- Department of Geography, University of Cambridge, Cambridge, UK
| | - Bijan Seyednasrollah
- School of Informatics, Computing, and Cyber Security, Northern Arizona University, Flagstaff, Arizona, USA
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
| | | | - Andrew D Richardson
- School of Informatics, Computing, and Cyber Security, Northern Arizona University, Flagstaff, Arizona, USA
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
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Su Z, Xiao Q, Shen J, Chen H, Yan S, Huang W. Metabolomics Analysis of Litchi Leaves during Floral Induction Reveals Metabolic Improvement by Stem Girdling. Molecules 2021; 26:4048. [PMID: 34279388 PMCID: PMC8271987 DOI: 10.3390/molecules26134048] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 06/28/2021] [Accepted: 06/29/2021] [Indexed: 11/17/2022] Open
Abstract
Prolonged exposure to cold temperatures often results in a relatively low flowering rate in litchi (Litchi chinensis Sonn.) trees with younger leaves. This study aimed to verify the impact of stem girdling on litchi flowering by identifying and characterizing the induced metabolic changes. After a 60 day exposure to cold treatment at 15 °C/10 °C (12 h/12 h), the flowering rate of the girdled trees was 100%, while that of the non-girdled trees was 20%, indicating that girdling improved litchi flowering at its turning stage. The metabolic profiles of litchi leaves with and without stem girdling during floral induction were compared and 505 metabolites potentially associated with litchi flowering were detected. Most metabolites were involved in the metabolism of starch and sucrose, fatty acid, and phenylpyruvic acid. The metabolic pathways concerned with the biosynthesis of epinephrine, sucrose, and d-maltose were induced in leaves after girdling treatment. The level of galactitol, phenylpyruvic acid, acetyl-CoA, linoleic acid, alpha-linolenic acid, and 13-HPOT biosynthesis remained stable in the leaves from girdled trees but changed drastically in the leaves from non-girdled trees. In addition, 379 metabolites concerning flowering rate were characterized. Metabolism pathways of starch and sucrose, galactose, and linoleic acid are of great significance to the flowering of litchi. Linoleic acid exhibited the most significant variations between girdled trees and non-girdled trees with fold changes of up to 13.62. These results contribute to understanding the biological mechanism of litchi floral induction and the metabolic changes after stem girdling.
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Affiliation(s)
- Zuanxian Su
- Guangdong Litchi Engineering Research Center, College of Horticulture, South China Agricultural University, Guangzhou 510642, China
| | - Qiushen Xiao
- Guangdong Litchi Engineering Research Center, College of Horticulture, South China Agricultural University, Guangzhou 510642, China
| | - Jiyuan Shen
- Guangdong Litchi Engineering Research Center, College of Horticulture, South China Agricultural University, Guangzhou 510642, China
| | - Houbin Chen
- Guangdong Litchi Engineering Research Center, College of Horticulture, South China Agricultural University, Guangzhou 510642, China
| | - Shijuan Yan
- Agro-Biological Gene Research Center, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China
| | - Wenjie Huang
- Agro-Biological Gene Research Center, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China
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Oberhuber W, Landlinger-Weilbold A, Schröter DM. Triggering Bimodal Radial Stem Growth in Pinus sylvestris at a Drought-Prone Site by Manipulating Stem Carbon Availability. FRONTIERS IN PLANT SCIENCE 2021; 12:674438. [PMID: 34122490 PMCID: PMC8193578 DOI: 10.3389/fpls.2021.674438] [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: 03/01/2021] [Accepted: 04/09/2021] [Indexed: 06/12/2023]
Abstract
A bimodal radial growth (RG) pattern, i.e., growth peaks in spring and autumn, was repeatedly found in trees in the Mediterranean regions, where summer drought causes reduction or cessation of cambial activity. In a dry inner Alpine valley of the Eastern Alps (Tyrol, Austria, 750 m asl), Pinus sylvestris shows unimodal RG with onset and cessation of cambial activity in early April and late June, respectively. A resumption of cambial activity after intense summer rainfall was not observed in this region. In a field experiment, we tested the hypothesis that early cessation of cambial activity at this drought-prone site is an adaptation to limited water availability leading to an early and irreversible switch of carbon (C) allocation to belowground. To accomplish this, the C status of young P. sylvestris trees was manipulated by physical blockage of phloem transport (girdling) 6 weeks after cessation of cambial cell division. Influence of manipulated C availability on RG was recorded by stem dendrometers, which were mounted above the girdling zone. In response to blockage of phloem flow, resumption of cambial activity was detected above girdling after about 2 weeks. Although the experimentally induced second growth surge lasted for the same period as in spring (c. 2 months), the increment was more than twice as large due to doubling of daily maximum RG rate. After girdling, wood anatomical traits above girdling no longer showed any significant differences between earlywood and latewood tracheids indicating pronounced effects of C availability on cell differentiation. Below girdling, no reactivation of cambial activity occurred, but cell wall thickness of last formed latewood cell was reduced due to lack of C supply after girdling. Intense RG resumption after girdling indicates that cessation of cambial activity can be reversed by manipulating C status of the stem. Hence, our girdling study yielded strong support for the hypothesis that belowground organs exert high C sink strengths on the drought-prone study site. Furthermore, this work highlights the need of in-depth experimental studies in order to understand the interactions between endogenous and exogenous factors on cambial activity and xylem cell differentiation more clearly.
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Affiliation(s)
- Walter Oberhuber
- Department of Botany, Leopold-Franzens-University of Innsbruck, Innsbruck, Austria
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Aboveground Wood Production Is Sustained in the First Growing Season after Phloem-Disrupting Disturbance. FORESTS 2020. [DOI: 10.3390/f11121306] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Carbon (C) cycling processes are particularly dynamic following disturbance, with initial responses often indicative of longer-term change. In northern Michigan, USA, we initiated the Forest Resilience Threshold Experiment (FoRTE) to identify the processes that sustain or lead to the decline of C cycling rates across multiple levels (0, 45, 65 and 85% targeted gross leaf area index loss) of disturbance severity and, in response, to separate disturbance types preferentially targeting large or small diameter trees. Simulating the effects of boring insects, we stem girdled > 3600 trees below diameter at breast height (DBH), immediately and permanently disrupting the phloem. Weekly DBH measurements of girdled and otherwise healthy trees (n > 700) revealed small but significant increases in daily aboveground wood net primary production (ANPPw) in the 65 and 85% disturbance severity treatments that emerged six weeks after girdling. However, we observed minimal change in end-of-season leaf area index and no significant differences in annual ANPPw among disturbance severities or between disturbance types, suggesting continued C fixation by girdled trees sustained stand-scale wood production in the first growing season after disturbance. We hypothesized higher disturbance severities would favor the growth of early successional species but observed no significant difference between early and middle to late successional species’ contributions to ANPPw across the disturbance severity gradient. We conclude that ANPPw stability immediately following phloem disruption is dependent on the continued, but inevitably temporary, growth of phloem-disrupted trees. Our findings provide insight into the tree-to-ecosystem mechanisms supporting stand-scale wood production stability in the first growing season following a phloem-disrupting disturbance.
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Darenova E, Horáček P, Krejza J, Pokorný R, Pavelka M. Seasonally varying relationship between stem respiration, increment and carbon allocation of Norway spruce trees. TREE PHYSIOLOGY 2020; 40:943-955. [PMID: 32268373 DOI: 10.1093/treephys/tpaa039] [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: 01/10/2020] [Revised: 03/04/2020] [Accepted: 03/18/2020] [Indexed: 06/11/2023]
Abstract
Stem respiration is an important component of an ecosystem's carbon budget. Beside environmental factors, it depends highly on tree energy demands for stem growth. Determination of the relationship between stem growth and stem respiration would help to reveal the response of stem respiration to changing climate, which is expected to substantially affect tree growth. Common measurement of stem radial increment does not record all aspects of stem growth processes, especially those connected with cell wall thickening; therefore, the relationship between stem respiration and stem radial increment may vary depending on the wood cell growth differentiation phase. This study presents results from measurements of stem respiration and increment carried out for seven growing seasons in a young Norway spruce forest. Moreover, rates of carbon allocation to stems were modeled for these years. Stem respiration was divided into maintenance (Rm) and growth respiration (Rg) based upon the mature tissue method. There was a close relationship between Rg and daily stem radial increment (dSRI), and this relationship differed before and after dSRI seasonal maximum, which was around 19 June. Before this date, Rg increased exponentially with dSRI, while after this date logarithmically. This is a result of later maxima of Rg and its slower decrease when compared with dSRI, which is connected with energy demands for cell wall thickening. Rg reached a maxima at the end of June or in July. The maximum of carbon allocation to stem peaked in late summer, when Rg mostly tended to decrease. The overall contribution of Rg to stem CO2 efflux amounted to 46.9% for the growing period from May to September and 38.2% for the year as a whole. This study shows that further deeper analysis of in situ stem growth and stem respiration dynamics is greatly needed, especially with a focus on wood formation on a cell level.
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Affiliation(s)
- Eva Darenova
- Global Change Research Institute CAS, v.v.i., Belidla 4a, 603 00 Brno, Czech Republic
| | - Petr Horáček
- Global Change Research Institute CAS, v.v.i., Belidla 4a, 603 00 Brno, Czech Republic
| | - Jan Krejza
- Global Change Research Institute CAS, v.v.i., Belidla 4a, 603 00 Brno, Czech Republic
- Department of Forest Ecology, Mendel University in Brno, Zemědělská 3, 613 00 Brno, Czech Republic
| | - Radek Pokorný
- Department of Silvilculture, Mendel University in Brno, Zemědělská 3, 613 00 Brno, Czech Republic
| | - Marian Pavelka
- Global Change Research Institute CAS, v.v.i., Belidla 4a, 603 00 Brno, Czech Republic
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10
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Collalti A, Tjoelker MG, Hoch G, Mäkelä A, Guidolotti G, Heskel M, Petit G, Ryan MG, Battipaglia G, Matteucci G, Prentice IC. Plant respiration: Controlled by photosynthesis or biomass? GLOBAL CHANGE BIOLOGY 2020; 26:1739-1753. [PMID: 31578796 DOI: 10.1111/gcb.14857] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Accepted: 10/01/2019] [Indexed: 06/10/2023]
Abstract
Two simplifying hypotheses have been proposed for whole-plant respiration. One links respiration to photosynthesis; the other to biomass. Using a first-principles carbon balance model with a prescribed live woody biomass turnover, applied at a forest research site where multidecadal measurements are available for comparison, we show that if turnover is fast the accumulation of respiring biomass is low and respiration depends primarily on photosynthesis; while if turnover is slow the accumulation of respiring biomass is high and respiration depends primarily on biomass. But the first scenario is inconsistent with evidence for substantial carry-over of fixed carbon between years, while the second implies far too great an increase in respiration during stand development-leading to depleted carbohydrate reserves and an unrealistically high mortality risk. These two mutually incompatible hypotheses are thus both incorrect. Respiration is not linearly related either to photosynthesis or to biomass, but it is more strongly controlled by recent photosynthates (and reserve availability) than by total biomass.
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Affiliation(s)
- Alessio Collalti
- Institute for Agriculture and Forestry Systems in the Mediterranean, National Research Council of Italy (CNR-ISAFOM), Rende (CS), Italy
- Department of Innovation in Biological, Agro-food and Forest Systems, University of Tuscia, Viterbo, Italy
| | - Mark G Tjoelker
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
| | - Günter Hoch
- Department of Environmental Sciences - Botany, University of Basel, Basel, Switzerland
| | - Annikki Mäkelä
- Institute for Atmospheric and Earth System Research (INAR), Faculty of Science and Faculty of Agriculture and Forestry, University of Helsinki, Helsinki, Finland
| | - Gabriele Guidolotti
- Institute of Research on Terrestrial Ecosystem, National Research Council of Italy (CNR-IRET), Rome, Italy
| | - Mary Heskel
- Department of Biology, Macalester College, Saint Paul, MN, USA
| | - Giai Petit
- Department of Land, Environment, Agriculture and Forestry, University of Padova, Padua, Italy
| | - Michael G Ryan
- Natural Resource Ecology Laboratory, Colorado State University, Fort Collins, CO, USA
- USDA Forest Service, Rocky Mountain Experiment Station, Fort Collins, CO, USA
| | - Giovanna Battipaglia
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania "L. Vanvitelli", Caserta, Italy
| | - Giorgio Matteucci
- Institute for Agriculture and Forestry Systems in the Mediterranean, National Research Council of Italy (CNR-ISAFOM), Rende (CS), Italy
| | - Iain Colin Prentice
- AXA Chair of Biosphere and Climate Impacts, Department of Life Sciences, Imperial College London, Ascot, UK
- Department of Biological Sciences, Macquarie University, North Ryde, NSW, Australia
- Department of Earth System Science, Ministry of Education Key Laboratory for Earth System Modeling, Tsinghua University, Beijing, China
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11
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Marler TE. Stem CO 2 efflux of Cycas micronesica is reduced by chronic non-native insect herbivory. PLANT SIGNALING & BEHAVIOR 2020; 15:1716160. [PMID: 31985317 PMCID: PMC7053932 DOI: 10.1080/15592324.2020.1716160] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 01/09/2020] [Accepted: 01/10/2020] [Indexed: 05/28/2023]
Abstract
Carbon dioxide efflux (Es) from the base of Cycas micronesica K.D. Hill stems was quantified in four locations containing healthy populations and in one location with populations threatened by non-native insect herbivores in order to determine the influence of reduced plant health on Es. Minimal variation of Es occurred among the four locations with healthy plants, and Es ranged from 1.68 to 1.79 µmol·m-2·s-1. The threatened in situ populations were on the island of Guam, where recent invasions of non-native insects have caused epidemic plant mortality, and the Es was 0.59 µmol·m-2·s-1. This is the first known report of Es for any cycad species, and the values for the unique pachycaulous stem form fit in the lower half of the range of published Es for woody trees. The results illuminate the potential for using Es to screen in situ C. micronesica populations to identify the individual trees with the greatest likelihood of surviving conservation measures.
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Affiliation(s)
- Thomas E. Marler
- Western Pacific Tropical Research Center, University of Guam, Mangilao, Guam, USA
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12
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Darenova E, Acosta M, Pokorny R, Pavelka M. Variability in temperature dependence of stem CO2 efflux from Norway spruce trees. TREE PHYSIOLOGY 2018; 38:1333-1344. [PMID: 29425384 DOI: 10.1093/treephys/tpy006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Accepted: 01/10/2018] [Indexed: 06/08/2023]
Abstract
This study presents results from continuous measurements of stem CO2 efflux carried out for seven experimental seasons (from May to October) in a young Norway spruce forest. The objectives of the study were to determine variability in the response of stem CO2 efflux to stem temperature over the season and to observe differences in the calculated relationship between stem temperature and CO2 efflux based on full growing season data or on data divided into periods according to stem growth rate. Temperature sensitivity of stem CO2 efflux (Q10) calculated for the established periods ranged between 1.61 and 3.46 and varied over the season, with the lowest values occurring in July and August. Q10 calculated using data from the full growing seasons ranged between 2.30 and 2.94 and was often significantly higher than Q10 calculated for the individual periods. Temperature-normalized stem CO2 efflux (R10) determined using Q10 from growing season data was overestimated when the temperature was below 10 °C and underestimated when the temperature was above 10 °C, compared with R10 calculated using Q10 established for the individual periods. The differences in daily mean R10 calculated by these two approaches ranged between -0.9 and 0.2 μmol CO2 m-2 s-1. The results of this study confirm that long periods for determining the temperature dependence of stem CO2 efflux encompass different statuses of the wood (especially in relation to stem growth). This may cause bias in models using this relationship for estimating stem CO2 efflux as a function of temperature.
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Affiliation(s)
- Eva Darenova
- Global Change Research Institute CAS, v.v.i., Belidla 4a, Brno, Czech Republic
| | - Manuel Acosta
- Global Change Research Institute CAS, v.v.i., Belidla 4a, Brno, Czech Republic
| | - Radek Pokorny
- Mendel University in Brno, Zemedelská 3, Brno, Czech Republic
| | - Marian Pavelka
- Global Change Research Institute CAS, v.v.i., Belidla 4a, Brno, Czech Republic
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Chan T, Berninger F, Kolari P, Nikinmaa E, Hölttä T. Linking stem growth respiration to the seasonal course of stem growth and GPP of Scots pine. TREE PHYSIOLOGY 2018; 38:1356-1370. [PMID: 29771366 PMCID: PMC6178967 DOI: 10.1093/treephys/tpy040] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Revised: 03/14/2018] [Accepted: 04/07/2018] [Indexed: 05/27/2023]
Abstract
Current methods to study relations between stem respiration and stem growth have been hampered by problems in quantifying stem growth from dendrometer measurements, particularly on a daily time scale. This is mainly due to the water-related influences within these measurements that mask growth. A previously published model was used to remove water-related influences from measured radial stem variations to reveal a daily radial growth signal (ΔˆGm). We analysed the intra- and inter-annual relations between ΔˆGm and estimated growth respiration rates (Rg) on a daily scale for 5 years. Results showed that Rg was weakly correlated to stem growth prior to tracheid formation, but was significant during the early summer. In the late summer, the correlation decreased slightly relative to the early summer. A 1-day time lag was found of ΔˆGm preceding Rg. Using wavelet analysis and measurements from eddy covariance, it was found that Rg followed gross primary production and temperature with a 2 and 3 h time lag, respectively.This study shows that further in-depth analysis of in-situ growth and growth respiration dynamics is greatly needed, with a focus on cellular respiration at specific developmental stages, its woody tissue costs and linkages to source-sink processes and environmental drivers.
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Affiliation(s)
- Tommy Chan
- Institute for Atmospheric and Earth System Research/Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, PO Box 27, Helsinki, Finland
- Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, PO Box 68, Helsinki, Finland
| | - Frank Berninger
- Institute for Atmospheric and Earth System Research/Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, PO Box 27, Helsinki, Finland
| | - Pasi Kolari
- Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, PO Box 68, Helsinki, Finland
| | - Eero Nikinmaa
- Institute for Atmospheric and Earth System Research/Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, PO Box 27, Helsinki, Finland
| | - Teemu Hölttä
- Institute for Atmospheric and Earth System Research/Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, PO Box 27, Helsinki, Finland
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Rainer-Lethaus G, Oberhuber W. Phloem Girdling of Norway Spruce Alters Quantity and Quality of Wood Formation in Roots Particularly Under Drought. FRONTIERS IN PLANT SCIENCE 2018; 9:392. [PMID: 29636766 PMCID: PMC5881222 DOI: 10.3389/fpls.2018.00392] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Accepted: 03/12/2018] [Indexed: 05/31/2023]
Abstract
Carbon (C) availability plays an essential role in tree growth and wood formation. We evaluated the hypothesis that a decrease in C availability (i) triggers mobilization of C reserves in the coarse roots of Picea abies to maintain growth and (ii) causes modification of wood structure notably under drought. The 6-year-old saplings were subjected to two levels of soil moisture (watered versus drought conditions) and root C status was manipulated by physically blocking phloem transport in the stem at three girdling dates (GDs). Stem girdling was done before the onset of bud break [day of the year (doy) 77], during vigorous aboveground shoot and radial stem growth (GD doy 138), and after cessation of shoot growth (GD doy 190). The effect of blockage of C transport on root growth, root phenology, and wood anatomical traits [cell lumen diameter (CLD) and cell wall thickness (CWT)] in earlywood (EW) and latewood (LW) was determined. To evaluate changes in belowground C status caused by girdling, non-structural carbohydrates (soluble sugars and starch) in coarse roots were determined at the time of girdling and after the growing season. Although fine root mass significantly decreased in response to blockage of phloem C transport, the phenology of root elongation growth was not affected. Surprisingly, radial root growth and CLD of EW tracheids in coarse roots were strikingly increased in drought-stressed trees, when girdling occurred before bud break or during aboveground stem growth. In watered trees, the growth response to girdling was less distinct, but the CWT of EW significantly increased. Starch reserves in the roots of girdled trees significantly decreased in both soil moisture treatments and at all GDs. We conclude that (i) radial growth and wood development in coarse roots of P. abies saplings are not only dependent on current photosynthates, and (ii) blockage of phloem transport induces physiological changes that outweigh drought effects imposed on root cambial activity and cell differentiation.
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Affiliation(s)
| | - Walter Oberhuber
- Department of Botany, University of Innsbruck, Innsbruck, Austria
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Salomón RL, De Schepper V, Valbuena-Carabaña M, Gil L, Steppe K. Daytime depression in temperature-normalised stem CO 2 efflux in young poplar trees is dominated by low turgor pressure rather than by internal transport of respired CO 2. THE NEW PHYTOLOGIST 2018; 217:586-598. [PMID: 28984360 DOI: 10.1111/nph.14831] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Accepted: 09/01/2017] [Indexed: 06/07/2023]
Abstract
Daytime decreases in temperature-normalised stem CO2 efflux (EA_D ) are commonly ascribed to internal transport of respired CO2 (FT ) or to an attenuated respiratory activity due to lowered turgor pressure. The two are difficult to separate as they are simultaneously driven by sap flow dynamics. To achieve combined gradients in turgor pressure and FT , sap flow rates in poplar trees were manipulated through severe defoliation, severe drought, moderate defoliation and moderate drought. Turgor pressure was mechanistically modelled using measurements of sap flow, stem diameter variation, and soil and stem water potential. A mass balance approach considering internal and external CO2 fluxes was applied to estimate FT . Under well-watered control conditions, both turgor pressure and sap flow, as a proxy of FT , were reliable predictors of EA_D . After tree manipulation, only turgor pressure was a robust predictor of EA_D . Moreover, FT accounted for < 15% of EA_D . Our results suggest that daytime reductions in turgor pressure and associated constrained growth are the main cause of EA_D in young poplar trees. Turgor pressure is determined by both carbohydrate supply and water availability, and should be considered to improve our widely used but inaccurate temperature-based predictions of woody tissue respiration in global models.
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Affiliation(s)
- Roberto L Salomón
- Laboratory of Plant Ecology, Department of Applied Ecology and Environmental Biology, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, B-9000, Ghent, Belgium
- Forest Genetics and Ecophysiology Research Group, E.T.S. Forestry Engineering, Technical University of Madrid, Ciudad Universitaria s/n, 28040, Madrid, Spain
| | - Veerle De Schepper
- Laboratory of Plant Ecology, Department of Applied Ecology and Environmental Biology, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, B-9000, Ghent, Belgium
| | - María Valbuena-Carabaña
- Forest Genetics and Ecophysiology Research Group, E.T.S. Forestry Engineering, Technical University of Madrid, Ciudad Universitaria s/n, 28040, Madrid, Spain
| | - Luis Gil
- Forest Genetics and Ecophysiology Research Group, E.T.S. Forestry Engineering, Technical University of Madrid, Ciudad Universitaria s/n, 28040, Madrid, Spain
| | - Kathy Steppe
- Laboratory of Plant Ecology, Department of Applied Ecology and Environmental Biology, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, B-9000, Ghent, Belgium
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16
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Arbellay E, Daniels LD, Mansfield SD, Chang AS. Cambial injury in lodgepole pine (Pinus contorta): mountain pine beetle vs fire. TREE PHYSIOLOGY 2017; 37:1611-1621. [PMID: 29121262 DOI: 10.1093/treephys/tpx102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 10/25/2017] [Indexed: 06/07/2023]
Abstract
Both mountain pine beetle (MPB) Dendroctonus ponderosae Hopkins and fire leave scars with similar appearance on lodgepole pine Pinus contorta Dougl. ex Loud. var. latifolia Engelm. that have never been compared microscopically, despite the pressing need to determine the respective effects of MPB and fire injury on tree physiology. We analysed changes in wood formation in naturally caused scars on lodgepole pine, and tested the hypotheses that (i) MPB and fire injury elicit distinct anomalies in lodgepole pine wood and (ii) anomalies differ in magnitude and/or duration between MPB and fire. Mountain pine beetle and fire injury reduced radial growth in the first year post-injury. Otherwise, radial growth and wood density increased over more than 10 years in both MPB and fire scars. We found that the general increase in radial growth was of greater magnitude (up to 27%) and of longer duration (up to 5 years) in fire scars compared with MPB scars, as shown in earlywood width. We also observed that the increase in latewood density was of greater magnitude (by 12%) in MPB scars, but of longer duration (by 4 years) in fire scars. Crystallinity decreased following MPB and fire injury, while microfibril angle increased. These changes in fibre traits were of longer duration (up to 4 years) in MPB scars compared with fire scars, as shown in microfibril angle. We found no significant changes in carbon and nitrogen concentrations. In conclusion, we stress that reduced competition and resistance to cavitation play an important role alongside cambial injury in influencing the type and severity of changes. In addition, more research is needed to validate the thresholds introduced in this study. Our findings serve as a foundation for new protocols to distinguish between bark beetle and fire disturbance, which is essential for improving our knowledge of historical bark beetle and fire regimes, and their interactions.
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Affiliation(s)
- Estelle Arbellay
- Tree-Ring Lab, Department of Forest and Conservation Sciences, University of British Columbia, 3041-2424 Main Mall, Vancouver, BC V6T 1Z4, Canada
| | - Lori D Daniels
- Tree-Ring Lab, Department of Forest and Conservation Sciences, University of British Columbia, 3041-2424 Main Mall, Vancouver, BC V6T 1Z4, Canada
| | - Shawn D Mansfield
- Department of Wood Science, University of British Columbia, 4030-2424 Main Mall, Vancouver, BC V6T 1Z4, Canada
| | - Alice S Chang
- Stable Isotope Facility, Department of Forest and Conservation Sciences, University of British Columbia, 3041-2424 Main Mall, Vancouver, BC V6T 1Z4, Canada
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17
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Winkler A, Oberhuber W. Cambial response of Norway spruce to modified carbon availability by phloem girdling. TREE PHYSIOLOGY 2017; 37:1527-1535. [PMID: 28651354 PMCID: PMC5718295 DOI: 10.1093/treephys/tpx077] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 05/31/2017] [Indexed: 05/09/2023]
Abstract
We tested the hypothesis that increase in carbon (C) availability in Norway spruce saplings (Picea abies (L.) Karst.) intensifies cambial cell division and increases cell lumen diameter (CLD) and cell wall thickness (CWT) when water availability is adequate. To accomplish this, we experimentally subjected 6-year-old P. abies saplings (n = 80 trees) to two levels of soil humidity (watered versus drought conditions) and manipulated tree C status by physically blocking phloem transport at three girdling dates (GDs). Stem girdling occurred in mid-March (day of the year (doy) 77) and in mid-May (GD doy 138), i.e., ~4 weeks before the onset of bud break and during vigorous stem growth, respectively, and in early July (GD doy 190), i.e., 6 and 4 weeks after cessation of radial growth in drought-stressed trees and shoot growth in both soil humidity (SH) treatments, respectively. In response to phloem blockage a striking increase in the number of xylem cells at all GDs and reactivation of cambial activity in drought-stressed trees was detected above the girdling zone, while below girdling xylem formation stopped in both SH-treatments. Although girdling differently affected wood anatomical parameters (CLD, CWT and CLD:CWT ratio) during earlywood and latewood formation, GD had a minor effect on cambial cell division and xylem cell differentiation. Results also revealed that phloem girdling outweighed drought effects imposed on cambial activity. We explain our findings by accumulation of carbohydrates, osmotically active sugars and/or C based signaling compound(s) in response to girdling. Altogether, we conclude that wood formation in P. abies saplings is limited by C availability, which is most likely caused by high C demand belowground especially under drought.
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Affiliation(s)
- Andrea Winkler
- Institute of Botany, Leopold-Franzens-University of Innsbruck, Sternwartestrasse 15, A-6020 Innsbruck, Austria
| | - Walter Oberhuber
- Institute of Botany, Leopold-Franzens-University of Innsbruck, Sternwartestrasse 15, A-6020 Innsbruck, Austria
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18
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Oberhuber W, Gruber A, Lethaus G, Winkler A, Wieser G. Stem girdling indicates prioritized carbon allocation to the root system at the expense of radial stem growth in Norway spruce under drought conditions. ENVIRONMENTAL AND EXPERIMENTAL BOTANY 2017; 138:109-118. [PMID: 28392608 PMCID: PMC5381714 DOI: 10.1016/j.envexpbot.2017.03.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
The early culmination of maximum radial growth (RG) in late spring has been found in several coniferous species in a dry inner Alpine environment. We hypothesized that an early decrease in RG is an adaptation to cope with drought stress, which might require an early switch of carbon (C) allocation to belowground organs. To test this hypothesis, we experimentally subjected six-year-old Norway spruce saplings (tree height: 1.35 m; n = 80 trees) to two levels of soil water availability (watered versus drought conditions) and manipulated tree C status by physically blocking phloem transport at three girdling dates (GD). The influence of C availability and drought on tree growth (radial and shoot growth; root biomass) in response to girdling was analyzed in both treatments. Non-structural carbohydrates (NSCs, soluble sugars and starch) were measured in the stem, root and current leader to evaluate changes in tree C status due to girdling. The main finding was a significant increase in RG of the girdled trees compared to the controls above the girdling zone (UZ). At all girdling dates the RG increase was significantly more intense in the drought-stressed compared with watered trees (c. 3.3 and 1.9-fold higher compared with controls in the drought-stressed and watered trees, respectively), most likely indicating that an early switch of C allocation to belowground occurs as an adaptation to maintain tree water status under drought conditions. Reactivation of the cambium after the cessation of its regular activity was detected in UZ in drought-stressed trees, while below the girdling zone no xylem formation was found and the NSC content was strikingly reduced. Irrespective of water availability, girdling before growth onset significantly reduced the progression of bud break (P < 0.05) and the length of the current leader shoot by -47% (P < 0.01) indicating a reduction in xylem hydraulic conductance, which was corroborated by significantly reduced xylem sap flow (P < 0.001). Based on our findings, we conclude that during the growing season drought stress prioritizes an early switch of C allocation to the root system as an adaptation to maintain adequate tree water status in drought-prone environments.
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Affiliation(s)
- Walter Oberhuber
- Institute of Botany, Leopold-Franzens-University of Innsbruck, Sternwartestrasse 15, A-6020 Innsbruck, Austria
| | - Andreas Gruber
- Institute of Botany, Leopold-Franzens-University of Innsbruck, Sternwartestrasse 15, A-6020 Innsbruck, Austria
| | - Gina Lethaus
- Institute of Botany, Leopold-Franzens-University of Innsbruck, Sternwartestrasse 15, A-6020 Innsbruck, Austria
| | - Andrea Winkler
- Institute of Botany, Leopold-Franzens-University of Innsbruck, Sternwartestrasse 15, A-6020 Innsbruck, Austria
| | - Gerhard Wieser
- Department of Alpine Timberline Ecophysiology, Federal Research and Training Centre for Forests, Natural Hazards and Landscape (BFW), Rennweg 1, A-6020 Innsbruck, Austria
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19
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Salomón RL, Valbuena-Carabaña M, Gil L, McGuire MA, Teskey RO, Aubrey DP, González-Doncel I, Rodríguez-Calcerrada J. Temporal and spatial patterns of internal and external stem CO2 fluxes in a sub-Mediterranean oak. TREE PHYSIOLOGY 2016; 36:1409-1421. [PMID: 27126229 DOI: 10.1093/treephys/tpw029] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Accepted: 03/12/2016] [Indexed: 06/05/2023]
Abstract
To accurately estimate stem respiration (RS), measurements of both carbon dioxide (CO2) efflux to the atmosphere (EA) and internal CO2 flux through xylem (FT) are needed because xylem sap transports respired CO2 upward. However, reports of seasonal dynamics of FT and EA are scarce and no studies exist in Mediterranean species under drought stress conditions. Internal and external CO2 fluxes at three stem heights, together with radial stem growth, temperature, sap flow and shoot water potential, were measured in Quercus pyrenaica Willd. in four measurement campaigns during one growing season. Substantial daytime depressions in temperature-normalized EA were observed throughout the experiment, including prior to budburst, indicating that diel hysteresis between stem temperature and EA cannot be uniquely ascribed to diversion of CO2 in the transpiration stream. Low internal [CO2] (<0.5%) resulted in low contributions of FT to RS throughout the growing season, and RS was mainly explained by EA (>90%). Internal [CO2] was found to vary vertically along the stems. Seasonality in resistance to radial CO2 diffusion was related to shoot water potential. The low internal [CO2] and FT observed in our study may result from the downregulation of xylem respiration in response to a legacy of coppicing as well as high radial diffusion of CO2 through cambium, phloem and bark tissues, which was related to low water content of stems. Long-term studies analyzing temporal and spatial variation in internal and external CO2 fluxes and their interactions are needed to mechanistically understand and model respiration of woody tissues.
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Affiliation(s)
- Roberto L Salomón
- Forest Genetics and Ecophysiology Research Group, E.T.S. Forestry Engineering, Technical University of Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain
| | - María Valbuena-Carabaña
- Forest Genetics and Ecophysiology Research Group, E.T.S. Forestry Engineering, Technical University of Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain
| | - Luis Gil
- Forest Genetics and Ecophysiology Research Group, E.T.S. Forestry Engineering, Technical University of Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain
| | - Mary Anne McGuire
- Warnell School of Forestry and Natural Resources, University of Georgia, 180 East Green St, Athens, GA 30602-2152, USA
| | - Robert O Teskey
- Warnell School of Forestry and Natural Resources, University of Georgia, 180 East Green St, Athens, GA 30602-2152, USA
| | - Doug P Aubrey
- Warnell School of Forestry and Natural Resources, University of Georgia, 180 East Green St, Athens, GA 30602-2152, USA
- Savannah River Ecology Lab, University of Georgia, Drawer E, Aiken, SC 29802, USA
| | - Inés González-Doncel
- Forest Genetics and Ecophysiology Research Group, E.T.S. Forestry Engineering, Technical University of Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain
| | - Jesús Rodríguez-Calcerrada
- Forest Genetics and Ecophysiology Research Group, E.T.S. Forestry Engineering, Technical University of Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain
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Reduced Winter Snowpack and Greater Soil Frost Reduce Live Root Biomass and Stimulate Radial Growth and Stem Respiration of Red Maple (Acer rubrum) Trees in a Mixed-Hardwood Forest. Ecosystems 2015. [DOI: 10.1007/s10021-015-9923-4] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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21
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Rodríguez-Calcerrada J, López R, Salomón R, Gordaliza GG, Valbuena-Carabaña M, Oleksyn J, Gil L. Stem CO2 efflux in six co-occurring tree species: underlying factors and ecological implications. PLANT, CELL & ENVIRONMENT 2015; 38:1104-1115. [PMID: 25292455 DOI: 10.1111/pce.12463] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Revised: 09/26/2014] [Accepted: 09/29/2014] [Indexed: 06/03/2023]
Abstract
Stem respiration plays a role in species coexistence and forest dynamics. Here we examined the intra- and inter-specific variability of stem CO2 efflux (E) in dominant and suppressed trees of six deciduous species in a mixed forest stand: Fagus sylvatica L., Quercus petraea [Matt.] Liebl, Quercus pyrenaica Willd., Prunus avium L., Sorbus aucuparia L. and Crataegus monogyna Jacq. We conducted measurements in late autumn. Within species, dominants had higher E per unit stem surface area (Es ) mainly because sapwood depth was higher than in suppressed trees. Across species, however, differences in Es corresponded with differences in the proportion of living parenchyma in sapwood and concentration of non-structural carbohydrates (NSC). Across species, Es was strongly and NSC marginally positively related with an index of drought tolerance, suggesting that slow growth of drought-tolerant trees is related to higher NSC concentration and Es . We conclude that, during the leafless period, E is indicative of maintenance respiration and is related with some ecological characteristics of the species, such as drought resistance; that sapwood depth is the main factor explaining variability in Es within species; and that the proportion of NSC in the sapwood is the main factor behind variability in Es among species.
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Affiliation(s)
- Jesús Rodríguez-Calcerrada
- Forest Genetics and Ecophysiology Research Group, School of Forestry Engineering, Technical University of Madrid, Madrid, 28040, Spain
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22
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Ritter W, Lehmeier CA, Winkler JB, Matyssek R, Edgar Grams TE. Contrasting carbon allocation responses of juvenile European beech (Fagus sylvatica) and Norway spruce (Picea abies) to competition and ozone. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2015; 196:534-543. [PMID: 25315225 DOI: 10.1016/j.envpol.2014.08.022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Revised: 07/23/2014] [Accepted: 08/25/2014] [Indexed: 06/04/2023]
Abstract
Allocation of recent photoassimilates of juvenile beech and spruce in response to twice-ambient ozone (2 × O(3)) and plant competition (i.e. intra vs. inter-specific) was examined in a phytotron study. To this end, we employed continuous (13)CO(2)/(12)CO(2) labeling during late summer and pursued tracer kinetics in CO(2) released from stems. In beech, allocation of recent photoassimilates to stems was significantly lowered under 2 × O(3) and increased in spruce when grown in mixed culture. As total tree biomass was not yet affected by the treatments, C allocation reflected incipient tree responses providing the mechanistic basis for biomass partitioning as observed in longer experiments. Compartmental modeling characterized functional properties of substrate pools supplying respiratory C demand. Respiration of spruce appeared to be exclusively supplied by recent photoassimilates. In beech, older C, putatively located in stem parenchyma cells, was a major source of respiratory substrate, reflecting the fundamental anatomical disparity between angiosperm beech and gymnosperm spruce.
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Affiliation(s)
- Wilma Ritter
- Ecophysiology of Plants, Department of Ecology and Ecosystem Management, Technische Universität München, Von-Carlowitz-Platz 2, 85354 Freising, Germany
| | - Christoph Andreas Lehmeier
- Lehrstuhl für Grünlandlehre, Department of Plant Sciences, Technische Universität München, Alte Akademie 12, 85350 Freising, Germany; Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK
| | - Jana Barbro Winkler
- Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Biochemical Plant Pathology, Department of Environmental Engineering, Ingolstädter Landstraße 1, 85764 Neuherberg, Germany
| | - Rainer Matyssek
- Ecophysiology of Plants, Department of Ecology and Ecosystem Management, Technische Universität München, Von-Carlowitz-Platz 2, 85354 Freising, Germany
| | - Thorsten Erhard Edgar Grams
- Ecophysiology of Plants, Department of Ecology and Ecosystem Management, Technische Universität München, Von-Carlowitz-Platz 2, 85354 Freising, Germany.
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Tarvainen L, Räntfors M, Wallin G. Vertical gradients and seasonal variation in stem CO2 efflux within a Norway spruce stand. TREE PHYSIOLOGY 2014; 34:488-502. [PMID: 24878562 DOI: 10.1093/treephys/tpu036] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Stem CO2 efflux is known to vary seasonally and vertically along tree stems. However, annual tree- and stand-scale efflux estimates are commonly based on measurements made only a few times a year, during daytime and at breast height. In this study, the effect of these simplifying assumptions on annual efflux estimates and their influence on the estimates of the importance of stems in stand-scale carbon cycling are evaluated. In order to assess the strength of seasonal, diurnal and along-stem variability in CO2 efflux, half-hourly measurements were carried out at three heights on three mature Norway spruce (Picea abies (L.) Karst.) trees over a period of 3 years. Making the common assumption of breast height efflux rates being representative of the entire stem was found to result in underestimations of 10-17% in the annual tree-scale CO2 efflux. Upscaling using only daytime measurements from breast height increased the underestimation to 15-20%. Furthermore, the results show that the strength of the vertical gradient varies seasonally, being strongest in the early summer and non-existent during the cool months. The observed seasonality in the vertical CO2 efflux gradient could not be explained by variation in stem temperature, temperature response of the CO2 efflux (Q10), outer-bark permeability, CO2 transport in the xylem or CO2 release from the phloem. However, the estimated CO2 concentration immediately beneath the bark was considerably higher in the upper stem during the main period of diameter growth, coinciding with the strongest vertical efflux gradient. These results suggest that higher growth rates in the upper stem are the main cause for the observed vertical variation in the stem CO2 effluxes. Furthermore, the results indicate that accounting for the vertical efflux variation is essential for assessments of the importance of stems in stand-scale carbon cycling.
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Affiliation(s)
- Lasse Tarvainen
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 461, SE-405 30 Gothenburg, Sweden Present address: Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), SE-901 83 Umeå, Sweden
| | - Mats Räntfors
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 461, SE-405 30 Gothenburg, Sweden
| | - Göran Wallin
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 461, SE-405 30 Gothenburg, Sweden
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Oberhuber W, Swidrak I, Pirkebner D, Gruber A. Temporal dynamics of non-structural carbohydrates and xylem growth in Pinus sylvestris exposed to drought. CANADIAN JOURNAL OF FOREST RESEARCH. JOURNAL CANADIEN DE LA RECHERCHE FORESTIERE 2011. [PMID: 22003262 DOI: 10.1139/x11-084] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Wood formation requires a continuous supply of carbohydrates for structural growth and metabolism. In the montane belt of the central Austrian Alps we monitored the temporal dynamics of xylem growth and non-structural carbohydrates (NSC) in stem sapwood of Pinus sylvestris L. during the growing season 2009, which was characterized by exceptional soil dryness within the study area. Soil water content dropped below 10 % at the time of maximum xylem growth end of May. Histological analyses have been used to describe cambial activity and xylem growth. Determination of NSC was performed using specific enzymatic assays revealing that total NSC ranged from 0.8 to 1.7 % dry matter throughout the year. Significant variations (P < 0.05) of the size of the NSC pool were observed during the growing season. Starch showed persistent abundance throughout the year reaching a maximum shortly before onset of late wood formation in mid-July. Seasonal dynamics of NSC and xylem growth suggest that (i) high sink activity occurred at start of the growing season in spring and during late wood formation in summer and (ii) there was no particular shortage in NSC, which caused P. sylvestris to draw upon stem reserves more heavily during drought in 2009.
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Affiliation(s)
- Walter Oberhuber
- Leopold-Franzens-University of Innsbruck, Institute of Botany, Sternwartestrasse 15, A-6020 Innsbruck, Austria
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Kuptz D, Fleischmann F, Matyssek R, Grams TEE. Seasonal patterns of carbon allocation to respiratory pools in 60-yr-old deciduous (Fagus sylvatica) and evergreen (Picea abies) trees assessed via whole-tree stable carbon isotope labeling. THE NEW PHYTOLOGIST 2011; 191:160-172. [PMID: 21395596 DOI: 10.1111/j.1469-8137.2011.03676.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
• The CO(2) efflux of adult trees is supplied by recent photosynthates and carbon (C) stores. The extent to which these C pools contribute to growth and maintenance respiration (R(G) and R(M), respectively) remains obscure. • Recent photosynthates of adult beech (Fagus sylvatica) and spruce (Picea abies) trees were labeled by exposing whole-tree canopies to (13) C-depleted CO(2). Label was applied three times during the year (in spring, early summer and late summer) and changes in the stable C isotope composition (δ(13) C) of trunk and coarse-root CO(2) efflux were quantified. • Seasonal patterns in C translocation rate (CTR) and fractional contribution of label to CO(2) efflux (F(Label-Max)) were found. CTR was fastest during early summer. In beech, F(Label-Max) was lowest in spring and peaked in trunks during late summer (0.6 ± 0.1, mean ± SE), whereas no trend was observed in coarse roots. No seasonal dynamics in F(Label-Max) were found in spruce. • During spring, the R(G) of beech trunks was largely supplied by C stores. Recent photosynthates supplied growth in early summer and refilled C stores in late summer. In spruce, CO(2) efflux was constantly supplied by a mixture of stored (c. 75%) and recent (c. 25%) C. The hypothesis that R(G) is exclusively supplied by recent photosynthates was rejected for both species.
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Affiliation(s)
- Daniel Kuptz
- Ecophysiology of Plants, Department of Ecology and Ecosystem Management, Life Science Center Weihenstephan, Technische Universität München, Hans-Carl-von-Carlowitz-Platz 2, 85354 Freising, Germany
| | - Frank Fleischmann
- Pathology of Woody Plants, Department of Ecology and Ecosystem Management, Life Science Center Weihenstephan, Technische Universität München, Hans-Carl-von-Carlowitz-Platz 2, 85354 Freising, Germany
| | - Rainer Matyssek
- Ecophysiology of Plants, Department of Ecology and Ecosystem Management, Life Science Center Weihenstephan, Technische Universität München, Hans-Carl-von-Carlowitz-Platz 2, 85354 Freising, Germany
| | - Thorsten E E Grams
- Ecophysiology of Plants, Department of Ecology and Ecosystem Management, Life Science Center Weihenstephan, Technische Universität München, Hans-Carl-von-Carlowitz-Platz 2, 85354 Freising, Germany
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Maunoury-Danger F, Fresneau C, Eglin T, Berveiller D, François C, Lelarge-Trouverie C, Damesin C. Impact of carbohydrate supply on stem growth, wood and respired CO2 delta13C: assessment by experimental girdling. TREE PHYSIOLOGY 2010; 30:818-30. [PMID: 20504776 DOI: 10.1093/treephys/tpq039] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
The present study examines the impact of the C source (reserves vs current assimilates) on tree C isotope signals and stem growth, using experimental girdling to stop the supply of C from leaves to stem. Two-year-old sessile oaks (Quercus petraea) were girdled at three different phenological periods during the leafy period: during early wood growth (Girdling Period 1), during late wood growth (Girdling Period 2) and just after growth cessation (Girdling Period 3). The measured variables included stem respiration rates, stem radial increment, delta(13)C of respired CO(2) and contents of starch and water-soluble fraction in stems (below the girdle) and leaves. Girdling stopped growth, even early in the growing season, leading to a decrease in stem CO(2) efflux (CO(2R)). Shift in substrate use from recently fixed carbohydrate to reserves (i.e., starch) induced (13)C enrichment of CO(2) respired by stem. However, change in substrate type was insufficient to explain alone all the observed CO(2R) delta(13)C variations, especially at the period corresponding to large growth rate of control trees. The below-girdle mass balance suggested that, during girdling periods, stem C was invested in metabolic pathways other than respiration and stem growth. After Girdling Period 1, the girdle healed and the effects of girdling on stem respiration were reversed. Stem growth restarted and total radial increment was similar to the control one, indicating that growth can be delayed when a stress event occurs early in the growth period. Concerning tree ring, seasonal shift in substrate use from reserves (i.e., starch) to recently fixed carbohydrate is sufficient to explain the observed (13)C depletion of tree ring during the early wood growth. However, the inter-tree intra-ring delta(13)C variability needs to be resolved in order to improve the interpretation of intra-seasonal ring signals in terms of climatic or ecophysiological information. This study highlighted, via carbohydrate availability effects, the importance of the characterization of stem metabolic pathways for a complete understanding of the delta(13)C signals.
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Affiliation(s)
- Florence Maunoury-Danger
- Laboratoire Ecologie, Systématique et Evolution, UMR 8079, Université Paris-Sud XI, 91405 Orsay CEDEX, France.
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