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Westerband AC, Wright IJ, Eller ASD, Cernusak LA, Reich PB, Perez-Priego O, Chhajed SS, Hutley LB, Lehmann CER. Nitrogen concentration and physical properties are key drivers of woody tissue respiration. ANNALS OF BOTANY 2022; 129:633-646. [PMID: 35245930 PMCID: PMC9113292 DOI: 10.1093/aob/mcac028] [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: 12/01/2021] [Accepted: 03/02/2022] [Indexed: 06/14/2023]
Abstract
BACKGROUND AND AIMS Despite the critical role of woody tissues in determining net carbon exchange of terrestrial ecosystems, relatively little is known regarding the drivers of sapwood and bark respiration. METHODS Using one of the most comprehensive wood respiration datasets to date (82 species from Australian rainforest, savanna and temperate forest), we quantified relationships between tissue respiration rates (Rd) measured in vitro (i.e. 'respiration potential') and physical properties of bark and sapwood, and nitrogen concentration (Nmass) of leaves, sapwood and bark. KEY RESULTS Across all sites, tissue density and thickness explained similar, and in some cases more, variation in bark and sapwood Rd than did Nmass. Higher density bark and sapwood tissues had lower Rd for a given Nmass than lower density tissues. Rd-Nmass slopes were less steep in thicker compared with thinner-barked species and less steep in sapwood than in bark. Including the interactive effects of Nmass, density and thickness significantly increased the explanatory power for bark and sapwood respiration in branches. Among these models, Nmass contributed more to explanatory power in trunks than in branches, and in sapwood than in bark. Our findings were largely consistent across sites, which varied in their climate, soils and dominant vegetation type, suggesting generality in the observed trait relationships. Compared with a global compilation of leaf, stem and root data, Australian species showed generally lower Rd and Nmass, and less steep Rd-Nmass relationships. CONCLUSIONS To the best of our knowledge, this is the first study to report control of respiration-nitrogen relationships by physical properties of tissues, and one of few to report respiration-nitrogen relationships in bark and sapwood. Together, our findings indicate a potential path towards improving current estimates of autotrophic respiration by integrating variation across distinct plant tissues.
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Affiliation(s)
- Andrea C Westerband
- Department of Biological Sciences, Macquarie University, North Ryde, NSW 2109, Australia
| | - Ian J Wright
- Department of Biological Sciences, Macquarie University, North Ryde, NSW 2109, Australia
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW 2751, Australia
| | - Allyson S D Eller
- Department of Biological Sciences, Macquarie University, North Ryde, NSW 2109, Australia
| | - Lucas A Cernusak
- College of Science and Engineering, James Cook University, Cairns, QLD 4878, Australia
| | - Peter B Reich
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW 2751, Australia
- Department of Forest Resources, University of Minnesota, St. Paul, MN 55108, USA
| | - Oscar Perez-Priego
- Department of Biological Sciences, Macquarie University, North Ryde, NSW 2109, Australia
| | - Shubham S Chhajed
- Department of Biological Sciences, Macquarie University, North Ryde, NSW 2109, Australia
| | - Lindsay B Hutley
- Research Institute for the Environment and Livelihoods, Charles Darwin University, NT 0909, Australia
| | - Caroline E R Lehmann
- Tropical Diversity, Royal Botanic Garden Edinburgh, Edinburgh EH3 5LR, UK
- School of Geosciences, University of Edinburgh, Edinburgh EH9 3FF, UK
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Katayama A, Kume T, Ichihashi R, Nakagawa M. Vertical variation in wood CO2 efflux is not uniformly related to height: measurement across various species and sizes of Bornean tropical rainforest trees. TREE PHYSIOLOGY 2019; 39:1000-1008. [PMID: 30976804 DOI: 10.1093/treephys/tpz022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 02/05/2019] [Accepted: 04/02/2019] [Indexed: 06/09/2023]
Abstract
Limited knowledge about vertical variation in wood CO2 efflux (Rwood) is still a cause of uncertainty in Rwood estimates at individual and ecosystem scales. Although previous studies found higher Rwood in the canopy, they examined several tree species of similar size. In contrast, in the present study, we measured vertical variation in Rwood for 18 trees including 13 species, using a canopy crane for a more precise determination of the vertical variation in Rwood, for various species and sizes of trees in order to examine the factors affecting vertical variation in Rwood and thus, to better understand the effect of taking into account the vertical and inter-individual variation on estimates of Rwood at the individual scale. We did not find any clear pattern of vertical variation; Rwood increased significantly with measurement height for only one tree, while it decreased for two more trees, and was not significantly related with measurement height in 15 other trees. Canopy to breast height Rwood ratio was not related to diameter at breast height or crown ratio, which supposedly are factors affecting vertical variation in Rwood. On average, Rwood estimates at individual scale, considering inter-individual variation but ignoring vertical variation, were only 6% higher than estimates considering both forms of variation. However, estimates considering vertical variation, while ignoring inter-individual variation, were 13% higher than estimates considering both forms of variation. These results suggest that individual measurements at breast height are more important for estimating Rwood at the individual scale, and that any error in Rwood estimation at this scale, due to the absence of any more measurements along tree height, is really quite negligible. This study measured various species and sizes of trees, which may be attributed to no clear vertical variation because factors causing vertical variation can differ among species and sizes.
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Affiliation(s)
- Ayumi Katayama
- Shiiba Research Forest, Kyushu University, Shiiba, Miyazaki, Japan
| | - Tomonori Kume
- Kasuya Research Forest, Kyushu University, Sasaguri, Fukuoka, Japan
- School of Forestry and Resource Conservation, National Taiwan University, Taipei, Taiwan
| | - Ryuji Ichihashi
- Shiiba Research Forest, Kyushu University, Shiiba, Miyazaki, Japan
| | - Michiko Nakagawa
- Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya, Japan
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Wittmann C, Pfanz H. More than just CO 2 -recycling: corticular photosynthesis as a mechanism to reduce the risk of an energy crisis induced by low oxygen. THE NEW PHYTOLOGIST 2018; 219:551-564. [PMID: 29767842 DOI: 10.1111/nph.15198] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Accepted: 03/19/2018] [Indexed: 06/08/2023]
Abstract
Reassimilation of internal CO2 via corticular photosynthesis (PScort ) has an important effect on the carbon economy of trees. However, little is known about its role as a source of O2 supply to the stem parenchyma and its implications in consumption and movement of O2 within trees. PScort of young Populus nigra (black poplar) trees was investigated by combining optical micro-optode measurements with monitoring of stem chlorophyll fluorescence. During times of zero sap flow in spring, stem oxygen concentrations (cO2 ) exhibited large temporal changes. In the sapwood, over 80% of diurnal changes in cO2 could be explained by respiration rates (Rd(mod) ). In the cortex, photosynthetic oxygen release during the day altered this relationship. With daytime illumination, oxygen levels in the cortex steadily increased from subambient and even exhibited a diel period of superoxia of up to 110% (% air sat.). By contrast, in the sapwood, cO2 never reached ambient levels; the diurnal oxygen deficit was up to 25% of air saturation. Our results confirm that PScort is not only a CO2 -recycling mechanism, it is also a mechanism to actively raise the cortical O2 concentration and counteract temporal/spatial hypoxia inside plant stems.
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Affiliation(s)
- Christiane Wittmann
- Department of Applied Botany and Volcano Biology, University of Duisburg-Essen, Essen, 45117, Germany
| | - Hardy Pfanz
- Department of Applied Botany and Volcano Biology, University of Duisburg-Essen, Essen, 45117, Germany
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4
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Fan H, McGuire MA, Teskey RO. Effects of stem size on stem respiration and its flux components in yellow-poplar (Liriodendron tulipifera L.) trees. TREE PHYSIOLOGY 2017; 37:1536-1545. [PMID: 28985420 DOI: 10.1093/treephys/tpx084] [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: 03/16/2017] [Accepted: 06/07/2017] [Indexed: 06/07/2023]
Abstract
Carbon dioxide (CO2) released from respiring cells in the stems of trees (RS) can diffuse radially to the atmosphere (EA) or dissolve in xylem sap and move internally in the tree (FT). Previous studies have observed that EA decreases as stem or branch diameter increases, but the cause of this relationship has not been determined, nor has the relationship been confirmed between stem diameter and RS, which includes both EA and FT. In this study, for the first time the mass balance technique was used to estimate RS of stems of Liriodendron tulipifera L. trees of different diameters, ranging from 16 to 60 cm, growing on the same site. The magnitude of the component fluxes scaled with tree size. Among the five trees, the contribution of EA to RS decreased linearly with increasing stem diameter and sapwood area while the contribution of FT to RS increased linearly with stem diameter and sapwood area. For the smallest tree EA was 86% of RS but it was only 46% of RS in the largest tree. As tree size increased a greater proportion of respired CO2 dissolved in sap and remained within the tree. Due to increase in FT with tree size, we observed that trees of different sizes had the same RS even though they had different EA. This appears to explain why the EA of stems and branches decreases as their size increases.
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Affiliation(s)
- Hailan Fan
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- Fujian Provincial Key Laboratory of Forest Ecosystem Processing and Management, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Mary Anne McGuire
- Warnell School of Forestry and Natural Resources, 180 E. Green Street, University of Georgia, Athens, GA 30602, USA
| | - Robert O Teskey
- Warnell School of Forestry and Natural Resources, 180 E. Green Street, University of Georgia, Athens, GA 30602, USA
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Yang J, He Y, Aubrey DP, Zhuang Q, Teskey RO. Global patterns and predictors of stem CO2 efflux in forest ecosystems. GLOBAL CHANGE BIOLOGY 2016; 22:1433-1444. [PMID: 26667780 DOI: 10.1111/gcb.13188] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Revised: 10/30/2015] [Accepted: 11/29/2015] [Indexed: 06/05/2023]
Abstract
Stem CO2 efflux (ES) plays an important role in the carbon balance of forest ecosystems. However, its primary controls at the global scale are poorly understood and observation-based global estimates are lacking. We synthesized data from 121 published studies across global forest ecosystems and examined the relationships between annual ES and biotic and abiotic factors at individual, biome, and global scales, and developed a global gridded estimate of annual ES . We tested the following hypotheses: (1) Leaf area index (LAI) will be highly correlated with annual ES at biome and global scales; (2) there will be parallel patterns in stem and root CO2 effluxes (RA) in all forests; (3) annual ES will decline with forest age; and (4) LAI coupled with mean annual temperature (MAT) and mean annual precipitation (MAP) will be sufficient to predict annual ES across forests in different regions. Positive linear relationships were found between ES and LAI, as well as gross primary production (GPP), net primary production (NPP), wood NPP, soil CO2 efflux (RS), and RA . Annual ES was correlated with RA in temperate forests after controlling for GPP and MAT, suggesting other additional factors contributed to the relationship. Annual ES tended to decrease with stand age. Leaf area index, MAT and MAP, predicted 74% of variation in ES at global scales. Our statistical model estimated a global annual ES of 6.7 ± 1.1 Pg C yr(-1) over the period of 2000-2012 with little interannual variability. Modeled mean annual ES was 71 ± 43, 270 ± 103, and 420 ± 134 g C m(2) yr(-1) for boreal, temperate, and tropical forests, respectively. We recommend that future studies report ES at a standardized constant temperature, incorporate more manipulative treatments, such as fertilization and drought, and whenever possible, simultaneously measure both aboveground and belowground CO2 fluxes.
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Affiliation(s)
- Jinyan Yang
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA, 30602, USA
| | - Yujie He
- Department of Earth, Atmospheric, and Planetary Sciences, Purdue University, West Lafayette, IN, 47907, USA
- Department of Earth System Science, University of California Irvine, Irvine, CA, 92697, USA
| | - Doug P Aubrey
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA, 30602, USA
- Savannah River Ecology Laboratory, University of Georgia, Aiken, SC, 29802, USA
| | - Qianlai Zhuang
- Department of Earth, Atmospheric, and Planetary Sciences, Purdue University, West Lafayette, IN, 47907, USA
- Department of Agronomy, Purdue University, West Lafayette, IN, 47907, USA
| | - Robert O Teskey
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA, 30602, USA
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6
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Gavrikov VL. Whether respiration in trees can scale isometrically with bole surface area: A test of hypothesis. Ecol Modell 2015. [DOI: 10.1016/j.ecolmodel.2015.06.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Sendall KM, Lusk CH, Reich PB. Becoming less tolerant with age: sugar maple, shade, and ontogeny. Oecologia 2015; 179:1011-21. [DOI: 10.1007/s00442-015-3428-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Accepted: 08/13/2015] [Indexed: 11/29/2022]
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Givnish TJ, Wong SC, Stuart-Williams H, Holloway-Phillips M, Farquhar GD. Determinants of maximum tree height inEucalyptusspecies along a rainfall gradient in Victoria, Australia. Ecology 2014. [DOI: 10.1890/14-0240.1] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Katayama A, Kume T, Komatsu H, Ohashi M, Matsumoto K, Ichihashi R, Kumagai T, Otsuki K. Vertical variations in wood CO2 efflux for live emergent trees in a Bornean tropical rainforest. TREE PHYSIOLOGY 2014; 34:503-512. [PMID: 24876294 DOI: 10.1093/treephys/tpu041] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Difficult access to 40-m-tall emergent trees in tropical rainforests has resulted in a lack of data related to vertical variations in wood CO2 efflux, even though significant variations in wood CO2 efflux are an important source of errors when estimating whole-tree total wood CO2 efflux. This study aimed to clarify vertical variations in wood CO2 efflux for emergent trees and to document the impact of the variations on the whole-tree estimates of stem and branch CO2 efflux. First, we measured wood CO2 efflux and factors related to tree morphology and environment for seven live emergent trees of two dipterocarp species at four to seven heights of up to ∼ 40 m for each tree using ladders and a crane. No systematic tendencies in vertical variations were observed for all the trees. Wood CO2 efflux was not affected by stem and air temperature, stem diameter, stem height or stem growth. The ratios of wood CO2 efflux at the treetop to that at breast height were larger in emergent trees with relatively smaller diameters at breast height. Second, we compared whole-tree stem CO2 efflux estimates using vertical measurements with those based on solely breast height measurements. We found similar whole-tree stem CO2 efflux estimates regardless of the patterns of vertical variations in CO2 efflux because the surface area in the canopy, where wood CO2 efflux often differed from that at breast height, was very small compared with that at low stem heights, resulting in little effect of the vertical variations on the estimate. Additionally, whole-tree branch CO2 efflux estimates using measured wood CO2 efflux in the canopy were considerably different from those measured using only breast height measurements. Uncertainties in wood CO2 efflux in the canopy did not cause any bias in stem CO2 efflux scaling, but affected branch CO2 efflux.
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Affiliation(s)
- Ayumi Katayama
- Field Science Center for Northern Biosphere, Hokkaido University, 250 Tokuda, Nayoro, Hokkaido 096-0071, Japan Kasuya Research Forest, Kyushu University, Sasaguri, Fukuoka 811-2415, Japan
| | - Tomonori Kume
- School of Forestry and Resource Conservation, National Taiwan University, Taipei 106-17, Taiwan
| | - Hikaru Komatsu
- The Hakubi Research Center for Advanced Research, Kyoto University, Kyoto 606-8302, Japan
| | - Mizue Ohashi
- School of Human Science and Environment, University of Hyogo, Himeji, Hyogo 670-0092, Japan
| | - Kazuho Matsumoto
- Faculty of Agriculture, University of the Ryukyus, Okinawa 903-0213, Japan
| | - Ryuji Ichihashi
- Kasuya Research Forest, Kyushu University, Sasaguri, Fukuoka 811-2415, Japan
| | - Tomo'omi Kumagai
- Hydrospheric Atmospheric Research Center, Nagoya University, Chikusa-ku, Nagoya 464-8601, Japan
| | - Kyoichi Otsuki
- Kasuya Research Forest, Kyushu University, Sasaguri, Fukuoka 811-2415, Japan
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10
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Larjavaara M. Maintenance cost, toppling risk and size of trees in a self-thinning stand. J Theor Biol 2010; 265:63-7. [DOI: 10.1016/j.jtbi.2010.04.021] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2009] [Revised: 03/30/2010] [Accepted: 04/20/2010] [Indexed: 10/19/2022]
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Teskey RO, Saveyn A, Steppe K, McGuire MA. Origin, fate and significance of CO2 in tree stems. THE NEW PHYTOLOGIST 2007; 177:17-32. [PMID: 18028298 DOI: 10.1111/j.1469-8137.2007.02286.x] [Citation(s) in RCA: 176] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Although some CO(2) released by respiring cells in tree stems diffuses directly to the atmosphere, on a daily basis 15-55% can remain within the tree. High concentrations of CO(2) build up in stems because of barriers to diffusion in the inner bark and xylem. In contrast with atmospheric [CO(2)] of c. 0.04%, the [CO(2)] in tree stems is often between 3 and 10%, and sometimes exceeds 20%. The [CO(2)] in stems varies diurnally and seasonally. Some respired CO(2) remaining in the stem dissolves in xylem sap and is transported toward the leaves. A portion can be fixed by photosynthetic cells in woody tissues, and a portion diffuses out of the stem into the atmosphere remote from the site of origin. It is now evident that measurements of CO(2) efflux to the atmosphere, which have been commonly used to estimate the rate of woody tissue respiration, do not adequately account for the internal fluxes of CO(2). New approaches to quantify both internal and external fluxes of CO(2) have been developed to estimate the rate of woody tissue respiration. A more complete assessment of internal fluxes of CO(2) in stems will improve our understanding of the carbon balance of trees.
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Affiliation(s)
- Robert O Teskey
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA
| | - An Saveyn
- Laboratory of Plant Ecology, Ghent University, Gent, Belgium
| | - Kathy Steppe
- Laboratory of Plant Ecology, Ghent University, Gent, Belgium
| | - Mary Anne McGuire
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA
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Spicer R, Holbrook NM. Parenchyma cell respiration and survival in secondary xylem: does metabolic activity decline with cell age? PLANT, CELL & ENVIRONMENT 2007; 30:934-43. [PMID: 17617821 DOI: 10.1111/j.1365-3040.2007.01677.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Sapwood respiration often declines towards the sapwood/heartwood boundary, but it is not known if parenchyma metabolic activity declines with cell age. We measured sapwood respiration in five temperate species (sapwood age range of 5-64 years) and expressed respiration on a live cell basis by quantifying living parenchyma. We found no effect of parenchyma age on respiration in two conifers (Pinus strobus, Tsuga canadensis), both of which had significant amounts of dead parenchyma in the sapwood. In angiosperms (Acer rubrum, Fraxinus americana, Quercus rubra), both bulk tissue and live cell respiration were reduced by about one-half in the oldest relative to the youngest sapwood, and all sapwood parenchyma remained alive. Conifers and angiosperms had similar bulk tissue respiration despite a smaller proportion of parenchyma in conifers (5% versus 15-25% in angiosperms), such that conifer parenchyma respired at rates about three times those of angiosperms. The fact that 5-year-old parenchyma cells respired at the same rate as 25-year-old cells in conifers suggests that there is no inherent or intrinsic decline in respiration as a result of cellular ageing. In contrast, it is not known whether differences observed in cellular respiration rates of angiosperms are a function of age per se, or whether active regulation of metabolic rate or positional effects (e.g. proximity to resources and/or hormones) could be the cause of reduced respiration in older sapwood.
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Affiliation(s)
- R Spicer
- Rowland Institute at Harvard University, 100 Edwin H. Land Boulevard, Cambridge, MA 02142, USA.
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Saveyn A, Steppe K, Lemeur R. Daytime depression in tree stem CO2 efflux rates: is it caused by low stem turgor pressure? ANNALS OF BOTANY 2007; 99:477-85. [PMID: 17204535 PMCID: PMC2802950 DOI: 10.1093/aob/mcl268] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
BACKGROUND AND AIMS Daytime CO2 efflux rates (FCO2) from tree stems are often reported to be lower than expected from the exponential relationship between temperature and respiration. Explanations of daytime depression in FCO2 have focused on the possible role of internal CO2 transport in the xylem. However, another possible cause that has been overlooked is the daily dynamics of the water status in the living stem tissues and its influence on stem growth rate and thus respiration. The objective of this study was to assess the daily dynamics of stem water status and growth rate and to determine the extent to which they may be linked to daily variations in stem FCO2. METHODS FCO2 of young beech and oak stems were measured under controlled conditions. Relative stem turgor pressure (Psi(p)), obtained from simulations with the 'RCGro' model, was used as an indicator of the water status in the living stem tissues. Daily dynamics of stem growth were derived from Psi(p): growth was assumed to occur when Psi(p) exceeded a relative threshold value. KEY RESULTS There was a strong correspondence between fluctuations in FCO2 and simulated Psi(p). The non-growth conditions during daytime coincided with depressions in FCO2. Moreover, FCO2 responded to changes in Psi(p) in the absence of growth, indicating also that maintenance processes were influenced by the water status in the living stem tissues. CONCLUSIONS Daytime depressions in stem FCO2 correlate with the daily dynamics of turgor, as a measure of the water status in the living stem tissues: it is suggested that water status of tree stems is a potentially important determinant of stem FCO2, as it influences the rate of growth and maintenance processes in the living tissues of the stem.
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Affiliation(s)
- An Saveyn
- Applied Ecology and Environmental Biology, Ghent University, Coupure Links 653, Ghent, 9000, Belgium.
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15
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McGuire MA, Cerasoli S, Teskey RO. CO2 fluxes and respiration of branch segments of sycamore (Platanus occidentalis L.) examined at different sap velocities, branch diameters, and temperatures. JOURNAL OF EXPERIMENTAL BOTANY 2007; 58:2159-68. [PMID: 17490994 DOI: 10.1093/jxb/erm069] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Respiration of stems and branches of trees (R(S)) has typically been estimated by measuring radial CO(2) efflux from woody tissue (E(A)) and rates of efflux are often scaled temporally using a temperature relationship (Q(10)). High concentrations of CO(2) in xylem sap ([CO(2)*]) have been shown to affect E(A), and the transport of CO(2) in the xylem stream has been suggested as a mechanism to explain field observations of temperature-independent fluctuations in E(A). Sap velocity and temperature were manipulated in detached branch segments of sycamore (Platanus occidentalis L.) under controlled conditions to quantify these effects. Within individual branches of similar size, E(A) and [CO(2)*] were greater at low sap velocity, while the amount of respired CO(2) transported in sap (transport flux, F(T)) was greater at high sap velocity. E(A) was linearly correlated with [CO(2)*]. In branches of three diameter classes (1, 2, and 3 cm), volume-based E(A), F(T), and R(S) did not differ, but surface-area based CO(2) fluxes increased with diameter class. Regardless of diameter, E(A) accounted for only 30% of respired CO(2) at high sap velocity, while at low sap velocity, E(A) accounted for 71% of respired CO(2). E(A), F(T), and R(S) measured at 5, 20, and 35 degrees C at the same sap velocity showed a typical exponential response to temperature. However, at the lowest temperature, E(A) accounted for only 18% of the CO(2) released from respiring cells compared with 44% at the highest temperature, perhaps due to the effect of temperature on the solubility of CO(2) in water. These results directly demonstrate the transport of respired CO(2) in the xylem stream and may help to explain inconsistencies in stem and branch respiration measurements made in situ.
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Affiliation(s)
- M A McGuire
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, Georgia 30602, USA.
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16
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Maier CA, Clinton BD. Relationship between stem CO2 efflux, stem sap velocity and xylem CO2 concentration in young loblolly pine trees. PLANT, CELL & ENVIRONMENT 2006; 29:1471-83. [PMID: 16898011 DOI: 10.1111/j.1365-3040.2006.01511.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
We measured diel patterns of stem surface CO2 efflux (Es, micromol m(-2) s(-1)), sap velocity (vs, mm s(-1)) and xylem CO2 concentration ([CO2]) (Xs, %) in 8-year-old loblolly pine trees during the spring to determine how vs and Xs influence Es. All trees showed a strong diel hysteresis between Es and stem temperature, where at a given temperature, Es was lower during the day than at night. Diel variations in temperature-independent Es were correlated with vs (R2= 0.54), such that at maximum vs, Es was reduced between 18 and 40%. However, this correlation may not represent a cause-and-effect relationship. In a subset of trees, vs was artificially reduced by progressively removing the tree canopy. Reducing vs to near zero had no effect on Es and did not change the diel hysteretic response to temperature. Diel Xs tended to decrease with vs and increase with Es, however, in defoliated trees, large increases in Xs, when vs approximately 0, had no effect on Es. We conclude that at this time of the year, Es is driven primarily by respiration of cambium and phloem tissues and that sap flow and xylem transport of CO2 had no direct influence on Es.
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Affiliation(s)
- Chris A Maier
- USDA Forest Service, Research Triangle Park, NC 27709, USA.
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17
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Characteristics of the temperature coefficient, Q 10, for the respiration of non-photosynthetic organs and soils of forest ecosystems. ACTA ACUST UNITED AC 2006. [DOI: 10.1007/s11461-006-0018-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Pruyn ML, Gartner BL, Harmon ME. Storage versus substrate limitation to bole respiratory potential in two coniferous tree species of contrasting sapwood width. JOURNAL OF EXPERIMENTAL BOTANY 2005; 56:2637-49. [PMID: 16118257 DOI: 10.1093/jxb/eri257] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Two coniferous tree species of contrasting sapwood width (Pinus ponderosa L., ponderosa pine and Pseudotsuga menziesii Mirb., Douglas-fir) were compared to determine whether bole respiratory potential was correlated with available storage space in ray parenchyma cells and/or respiratory substrate concentration of tissues (total nitrogen content, N; and total non-structural carbohydrate content, TNC). An increment core-based, laboratory method under controlled temperature was used to measure tissue-level respiration (termed respiratory potential) from multiple positions in mature boles (>100-years-old). The most significant tissue-level differences that occurred were that N and TNC were two to six times higher for inner bark than sapwood, TNC was about two times higher in ponderosa pine than Douglas-fir and there was significant seasonal variation in TNC. Ray cell abundance was not correlated with sapwood respiratory potential, whereas N and TNC often were, implying that respiratory potential tended to be more limited by substrate than storage space. When scaled from cores to whole boles (excluding branches), potential net CO2 efflux correlated positively with live bole volume (inner bark plus sapwood), live bole ray volume, N mass, and TNC mass (adjusted R2 > or =0.4). This relationship did not differ between species for N mass, but did for live bole volume, live bole ray volume, and TNC mass. Therefore, N mass appeared to be a good predictor of bole respiratory potential. The differences in net CO2 efflux between the species were largely explained by the species' relative amounts of whole-bole storage space or substrate mass. For example, ponderosa pine's inner bark was thinner than Douglas-fir's, which had the greater concentration of ray cells and TNC compared with the sapwood. This resulted in ponderosa pine boles having 30-60% less ray volume and 10-30% less TNC mass, and caused ponderosa pine net CO2 efflux/ray volume and net CO2 efflux/TNC mass to be 20-50% higher than Douglas-fir. In addition, because inner bark respiratory potential was 2-25 times higher than that of sapwood, ponderosa pine's thinner inner bark and deeper sapwood (relative to Douglas-fir) caused its bole net CO2 efflux/live bole volume to be 20-25% lower than that of similarly-sized Douglas-fir trees.
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Affiliation(s)
- Michele L Pruyn
- Department of Forest Science, Oregon State University, Corvallis, OR 97331-5752, USA.
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Bowman WP, Barbour MM, Turnbull MH, Tissue DT, Whitehead D, Griffin KL. Sap flow rates and sapwood density are critical factors in within- and between-tree variation in CO2 efflux from stems of mature Dacrydium cupressinum trees. THE NEW PHYTOLOGIST 2005; 167:815-28. [PMID: 16101918 DOI: 10.1111/j.1469-8137.2005.01478.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Measurements of CO2 efflux from stems and branches, sap velocity, and respiratory activity of excised wood cores were conducted in Dacrydium cupressinum trees that differed in diameter, age, and canopy emergence. The objective of this study was to determine if consistent linkages exist among respiratory production of CO2 within stems, xylem transport of CO2, and the rate of CO2 diffusing from stem surfaces. Stem CO2 efflux was depressed during periods of sap flow compared with the efflux rate expected for a given stem temperature and was positively correlated with sapwood density. By contrast, no significant relationships were observed between CO2 efflux and the respiratory activity of wood tissues. Between 86 and 91% of woody tissue respiration diffused to the atmosphere over a 24-h period. However, at certain times of the day, xylem transport and internal storage of CO2 may account for up to 13-38% and 12-18%, respectively, of woody tissue respiration. These results demonstrate that differences in sap flow rates and xylem anatomy are critically important for explaining within- and between-tree variation in CO2 efflux from stems.
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Affiliation(s)
- William P Bowman
- Department of Ecology, Evolution, and Environmental Biology, Columbia University, New York, NY 10025, USA.
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Pruyn ML, Gartner BL, Harmon ME. Within-stem variation of respiration in Pseudotsuga menziesii (Douglas-fir) trees. THE NEW PHYTOLOGIST 2002; 154:359-372. [PMID: 33873424 DOI: 10.1046/j.1469-8137.2002.00380.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
• A technique for measuring in vitro respiration was investigated to understand why rates were higher than those reported in vivo and to elucidate trends within mature Pseudotsuga menziesii (Douglas-fir) trees. • Extracted increment cores were divided into 3-4 radial depths and a gas chromatograph was used to compare respiration rates radially and vertically within stems. • Respiration of inner bark was 2-3 times greater than sapwood, and 50-70% higher in outer than inner sapwood. Inner bark and outer sapwood released > 40% more CO2 at treetops than at bases. Trends were robust for CO2 production on a core dry-mass, volume, or total carbon basis. By contrast, CO2 production on a nitrogen basis showed almost no significant variation. • This in vitro technique provided an effective index for relative differences in respiration within tree stems. Discrepancies between in vitro and in vivo measurements might be related to the gaseous environment in stems. The estimated within-stem gradients in respiration were possibly determined by enzyme quantity and availability and could be useful in scaling to whole-trees.
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Affiliation(s)
- Michele L Pruyn
- Department of Wood Science and Engineering/Department of Forest Science, Forest Research Laboratory, Richardson Hall, Oregon State University, Corvallis, OR 97331-7402, USA
| | - Barbara L Gartner
- Department of Wood Science and Engineering/Department of Forest Science, Forest Research Laboratory, Richardson Hall, Oregon State University, Corvallis, OR 97331-7402, USA
| | - Mark E Harmon
- Department of Forest Science, Forest Science Laboratory, Richardson Hall, Oregon State University, Corvallis, OR 97331-7402, USA
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