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Garen JC, Michaletz ST. Fast Assimilation-Temperature Response: a FAsTeR method for measuring the temperature dependence of leaf-level photosynthesis. THE NEW PHYTOLOGIST 2024; 241:1361-1372. [PMID: 37984070 DOI: 10.1111/nph.19405] [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: 08/23/2023] [Accepted: 10/27/2023] [Indexed: 11/22/2023]
Abstract
We present the Fast Assimilation-Temperature Response (FAsTeR) method, a new method for measuring plant assimilation-temperature (AT) response that reduces measurement time and increases data density compared with conventional methods. The FAsTeR method subjects plant leaves to a linearly increasing temperature ramp while taking rapid, nonequilibrium measurements of gas exchange variables. Two postprocessing steps are employed to correct measured assimilation rates for nonequilibrium effects and sensor calibration drift. Results obtained with the new method are compared with those from two conventional stepwise methods. Our new method accurately reproduces results obtained from conventional methods, reduces measurement time by a factor of c. 3.3 (from c. 90 to 27 min), and increases data density by a factor of c. 55 (from c. 10 to c. 550 observations). Simulation results demonstrate that increased data density substantially improves confidence in parameter estimates and drastically reduces the influence of noise. By improving measurement speed and data density, the FAsTeR method enables users to ask fundamentally new kinds of ecological and physiological questions, expediting data collection in short-field campaigns, and improving the representativeness of data across species in the literature.
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Affiliation(s)
- Josef C Garen
- Department of Botany and Biodiversity Research Centre, The University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Sean T Michaletz
- Department of Botany and Biodiversity Research Centre, The University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
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2
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Schmiege SC, Heskel M, Fan Y, Way DA. It's only natural: Plant respiration in unmanaged systems. PLANT PHYSIOLOGY 2023; 192:710-727. [PMID: 36943293 PMCID: PMC10231469 DOI: 10.1093/plphys/kiad167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Revised: 02/27/2023] [Accepted: 02/27/2023] [Indexed: 06/01/2023]
Abstract
Respiration plays a key role in the terrestrial carbon cycle and is a fundamental metabolic process in all plant tissues and cells. We review respiration from the perspective of plants that grow in their natural habitat and how it is influenced by wide-ranging elements at different scales, from metabolic substrate availability to shifts in climate. Decades of field-based measurements have honed our understanding of the biological and environmental controls on leaf, root, stem, and whole-organism respiration. Despite this effort, there remain gaps in our knowledge within and across species and ecosystems, especially in more challenging-to-measure tissues like roots. Recent databases of respiration rates and associated leaf traits from species representing diverse biomes, plant functional types, and regional climates have allowed for a wider-lens view at modeling this important CO2 flux. We also re-analyze published data sets to show that maximum leaf respiration rates (Rmax) in species from around the globe are related both to leaf economic traits and environmental variables (precipitation and air temperature), but that root respiration does not follow the same latitudinal trends previously published for leaf data. We encourage the ecophysiological community to continue to expand their study of plant respiration in tissues that are difficult to measure and at the whole plant and ecosystem levels to address outstanding questions in the field.
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Affiliation(s)
- Stephanie C Schmiege
- Plant Resilience Institute, Michigan State University, East Lansing, MI, 48824, USA
- Department of Biology, Western University, N6A 3K7, London, ON, Canada
| | - Mary Heskel
- Department of Biology, Macalester College, Saint Paul, MN, USA 55105
| | - Yuzhen Fan
- Research School of Biology, The Australian National University, Acton, ACT, Australia
| | - Danielle A Way
- Department of Biology, Western University, N6A 3K7, London, ON, Canada
- Research School of Biology, The Australian National University, Acton, ACT, Australia
- Environmental & Climate Sciences Department, Brookhaven National Laboratory, Upton, NY, USA
- Nicholas School of the Environment, Duke University, Durham, NC, USA
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3
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Griffin KL, Griffin ZM, Schmiege SC, Bruner SG, Boelman NT, Vierling LA, Eitel JUH. Variation in White spruce needle respiration at the species range limits: A potential impediment to Northern expansion. PLANT, CELL & ENVIRONMENT 2022; 45:2078-2092. [PMID: 35419840 DOI: 10.1111/pce.14333] [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: 08/19/2021] [Revised: 04/06/2022] [Accepted: 04/10/2022] [Indexed: 06/14/2023]
Abstract
White spruce (Picea glauca) spans a massive range, yet the variability in respiratory physiology and related implications for tree carbon balance at the extremes of this distribution remain as enigmas. Working at both the most northern and southern extents of the distribution range more than 5000 km apart, we measured the short-term temperature response of dark respiration (R/T) at upper and lower canopy positions. R/T curves were fit to both polynomial and thermodynamic models so that model parameters could be compared among locations, canopy positions, and with previously published data. Respiration measured at 25°C (R25 ) was 68% lower at the southern location than at the northern location, resulting in a significantly lower intercept in R/T response in temperate trees. Only at the southern location did upper canopy leaves have a steeper temperature response than lower canopy leaves, likely reflecting canopy gradients in light. At the northern range limit respiration is nearly twice that of the average R25 reported in a global leaf respiration database. We predict that without significant thermal acclimation, respiration will increase with projected end-of-the-century warming and will likely constrain the future range limits of this important boreal species.
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Affiliation(s)
- Kevin L Griffin
- Department of Earth and Environmental Sciences, Columbia University, Palisades, New York, USA
- Department of Ecology, Evolution and Environmental Biology, Columbia University, New York, New York, USA
- Lamont-Doherty Earth Observatory, Columbia University, Palisades, New York, USA
| | - Zoe M Griffin
- Department of Geography & Environmental Sustainability, SUNY Oneonta, Oneonta, New York, USA
| | - Stephanie C Schmiege
- Department of Ecology, Evolution and Environmental Biology, Columbia University, New York, New York, USA
- New York Botanical Garden, Bronx, New York, USA
| | - Sarah G Bruner
- Department of Ecology, Evolution and Environmental Biology, Columbia University, New York, New York, USA
| | - Natalie T Boelman
- Lamont-Doherty Earth Observatory, Columbia University, Palisades, New York, USA
| | - Lee A Vierling
- Department of Natural Resources and Society, College of Natural Resources, University of Idaho, Moscow, Idaho, USA
| | - Jan U H Eitel
- Department of Natural Resources and Society, College of Natural Resources, University of Idaho, Moscow, Idaho, USA
- McCall Outdoor Science School, College of Natural Resources, University of Idaho, McCall, Idaho, USA
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4
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Crous KY, Uddling J, De Kauwe MG. Temperature responses of photosynthesis and respiration in evergreen trees from boreal to tropical latitudes. THE NEW PHYTOLOGIST 2022; 234:353-374. [PMID: 35007351 PMCID: PMC9994441 DOI: 10.1111/nph.17951] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 12/03/2021] [Indexed: 05/29/2023]
Abstract
Evergreen species are widespread across the globe, representing two major plant functional forms in terrestrial models. We reviewed and analysed the responses of photosynthesis and respiration to warming in 101 evergreen species from boreal to tropical biomes. Summertime temperatures affected both latitudinal gas exchange rates and the degree of responsiveness to experimental warming. The decrease in net photosynthesis at 25°C (Anet25 ) was larger with warming in tropical climates than cooler ones. Respiration at 25°C (R25 ) was reduced by 14% in response to warming across species and biomes. Gymnosperms were more sensitive to greater amounts of warming than broadleaved evergreens, with Anet25 and R25 reduced c. 30-40% with > 10°C warming. While standardised rates of carboxylation (Vcmax25 ) and electron transport (Jmax25 ) adjusted to warming, the magnitude of this adjustment was not related to warming amount (range 0.6-16°C). The temperature optimum of photosynthesis (ToptA ) increased on average 0.34°C per °C warming. The combination of more constrained acclimation of photosynthesis and increasing respiration rates with warming could possibly result in a reduced carbon sink in future warmer climates. The predictable patterns of thermal acclimation across biomes provide a strong basis to improve modelling predictions of the future terrestrial carbon sink with warming.
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Affiliation(s)
- Kristine Y. Crous
- Hawkesbury Institute for the EnvironmentWestern Sydney UniversityLocked Bag 1797PenrithNSW2751Australia
| | - Johan Uddling
- Department of Biological and Environmental SciencesUniversity of GothenburgPO Box 461GothenburgSE‐405 30Sweden
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Inoue T, Yamada Y, Noguchi K. Growth temperature affects O 2 consumption rates and plasticity of respiratory flux to support shoot growth at various growth temperatures. PLANT, CELL & ENVIRONMENT 2022; 45:133-146. [PMID: 34719799 DOI: 10.1111/pce.14217] [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: 06/30/2021] [Revised: 10/20/2021] [Accepted: 10/22/2021] [Indexed: 06/13/2023]
Abstract
The temperature dependence of respiration rates and their acclimation to growth temperature vary among species/ecotypes, but the details remain unclear. Here, we compared the temperature dependence of shoot O2 consumption rates among Arabidopsis thaliana ecotypes to clarify how the temperature dependence and their acclimation to temperature differ among ecotypes, and how these differences relate to shoot growth. We examined growth analysis, temperature dependence of O2 consumption rates, and protein amounts of the respiratory chain components in shoots of twelve ecotypes of A. thaliana grown at three different temperatures. The temperature dependence of the O2 consumption rates were fitted to the modified Arrhenius model. The dynamic response of activation energy to measurement temperature was different among growth temperatures, suggesting that the plasticity of respiratory flux to temperatures differs among growth temperatures. The similar values of activation energy at growth temperature among ecotypes suggest that a similar process may determine the O2 consumption rates at the growth temperature in any ecotype. These results suggest that the growth temperature affects not only the absolute rate of O2 consumption but also the plasticity of respiratory flux in response to temperature, supporting the acclimation of shoot growth to various temperatures.
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Affiliation(s)
- Tomomi Inoue
- National Institute for Environmental Studies, Ibaraki, Japan
| | - Yusuke Yamada
- School of Life Science, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan
| | - Ko Noguchi
- School of Life Science, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan
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6
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Griffin KL, Schmiege SC, Bruner SG, Boelman NT, Vierling LA, Eitel JUH. High Leaf Respiration Rates May Limit the Success of White Spruce Saplings Growing in the Kampfzone at the Arctic Treeline. FRONTIERS IN PLANT SCIENCE 2021; 12:746464. [PMID: 34790212 PMCID: PMC8591130 DOI: 10.3389/fpls.2021.746464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 10/01/2021] [Indexed: 06/13/2023]
Abstract
Arctic Treeline is the transition from the boreal forest to the treeless tundra and may be determined by growing season temperatures. The physiological mechanisms involved in determining the relationship between the physical and biological environment and the location of treeline are not fully understood. In Northern Alaska, we studied the relationship between temperature and leaf respiration in 36 white spruce (Picea glauca) trees, sampling both the upper and lower canopy, to test two research hypotheses. The first hypothesis is that upper canopy leaves, which are more directly coupled to the atmosphere, will experience more challenging environmental conditions and thus have higher respiration rates to facilitate metabolic function. The second hypothesis is that saplings [stems that are 5-10cm DBH (diameter at breast height)] will have higher respiration rates than trees (stems ≥10cm DBH) since saplings represent the transition from seedlings growing in the more favorable aerodynamic boundary layer, to trees which are fully coupled to the atmosphere but of sufficient size to persist. Respiration did not change with canopy position, however respiration at 25°C was 42% higher in saplings compared to trees (3.43±0.19 vs. 2.41±0.14μmolm-2 s-1). Furthermore, there were significant differences in the temperature response of respiration, and seedlings reached their maximum respiration rates at 59°C, more than two degrees higher than trees. Our results demonstrate that the respiratory characteristics of white spruce saplings at treeline impose a significant carbon cost that may contribute to their lack of perseverance beyond treeline. In the absence of thermal acclimation, the rate of leaf respiration could increase by 57% by the end of the century, posing further challenges to the ecology of this massive ecotone.
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Affiliation(s)
- Kevin L. Griffin
- Department of Earth and Environmental Sciences, Columbia University, Palisades, NY, United States
- Department of Ecology, Evolution and Environmental Biology, Columbia University, New York, NY, United States
- Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY, United States
| | - Stephanie C. Schmiege
- Department of Ecology, Evolution and Environmental Biology, Columbia University, New York, NY, United States
- New York Botanical Garden, Bronx, NY, United States
| | - Sarah G. Bruner
- Department of Ecology, Evolution and Environmental Biology, Columbia University, New York, NY, United States
| | - Natalie T. Boelman
- Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY, United States
| | - Lee A. Vierling
- Department of Natural Resources and Society, College of Natural Resources, University of Idaho, Moscow, ID, United States
| | - Jan U. H. Eitel
- Department of Natural Resources and Society, College of Natural Resources, University of Idaho, Moscow, ID, United States
- McCall Outdoor Science School, College of Natural Resources, University of Idaho, McCall, ID, United States
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7
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Wilcots ME, Harpole WS, Seabloom EW, Borer ET. Community change can buffer chronic nitrogen impacts, but multiple nutrients tip the scale. Ecology 2021; 102:e03355. [PMID: 33797757 DOI: 10.1002/ecy.3355] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 12/22/2020] [Accepted: 02/05/2021] [Indexed: 11/08/2022]
Abstract
Anthropogenic nitrogen (N) inputs are causing large changes in ecosystems worldwide. Many previous studies have examined the impact of N on terrestrial ecosystems; however, most have added N at rates that are much higher than predicted future deposition rates. Here, we present the results from a gradient of experimental N addition (0-10 g·N·m-2 ) in a temperate grassland. After a decade of N addition, we found that all levels of N addition changed plant functional group composition, likely indicating altered function for plant communities exposed to 10 yr of N inputs. However, N addition only had weak impacts on species composition and this functional group shift was not driven by any particular species, suggesting high levels of functional redundancy among grasslands species. Adding other nutrients (P, K, and micronutrients) in combination with N caused substantially greater changes in the relative abundance of species and functional groups. Together, these results suggest that compositional change within functional groups may buffer grasslands from impacts of N deposition, but concurrent eutrophication with other elements will likely lead to substantial changes in plant composition and biomass.
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Affiliation(s)
- Megan E Wilcots
- Department of Ecology, Evolution, and Behavior, University of Minnesota, 1987 Upper Buford Circle, St. Paul, Minnesota, 55108, USA
| | - W Stanley Harpole
- Department of Physiological Diversity, Helmholtz Center for Environmental Research - UFZ, Permoserstrasse 15, Leipzig, 04318, Germany.,German Centre for Integrative Biodiversity Research (iDiv), Puschstrasse 4, Leipzig, 04103, Germany.,Martin Luther University Halle-Wittenberg, am Kirchtor 1, Halle (Saale), 06108, Germany
| | - Eric W Seabloom
- Department of Ecology, Evolution, and Behavior, University of Minnesota, 1987 Upper Buford Circle, St. Paul, Minnesota, 55108, USA
| | - Elizabeth T Borer
- Department of Ecology, Evolution, and Behavior, University of Minnesota, 1987 Upper Buford Circle, St. Paul, Minnesota, 55108, USA
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8
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Aspinwall MJ, Pfautsch S, Tjoelker MG, Vårhammar A, Possell M, Drake JE, Reich PB, Tissue DT, Atkin OK, Rymer PD, Dennison S, Van Sluyter SC. Range size and growth temperature influence Eucalyptus species responses to an experimental heatwave. GLOBAL CHANGE BIOLOGY 2019; 25:1665-1684. [PMID: 30746837 DOI: 10.1111/gcb.14590] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Revised: 02/03/2019] [Accepted: 02/04/2019] [Indexed: 05/24/2023]
Abstract
Understanding forest tree responses to climate warming and heatwaves is important for predicting changes in tree species diversity, forest C uptake, and vegetation-climate interactions. Yet, tree species differences in heatwave tolerance and their plasticity to growth temperature remain poorly understood. In this study, populations of four Eucalyptus species, two with large range sizes and two with comparatively small range sizes, were grown under two temperature treatments (cool and warm) before being exposed to an equivalent experimental heatwave. We tested whether the species with large and small range sizes differed in heatwave tolerance, and whether trees grown under warmer temperatures were more tolerant of heatwave conditions than trees grown under cooler temperatures. Visible heatwave damage was more common and severe in the species with small rather than large range sizes. In general, species that showed less tissue damage maintained higher stomatal conductance, lower leaf temperatures, larger increases in isoprene emissions, and less photosynthetic inhibition than species that showed more damage. Species exhibiting more severe visible damage had larger increases in heat shock proteins (HSPs) and respiratory thermotolerance (Tmax ). Thus, across species, increases in HSPs and Tmax were positively correlated, but inversely related to increases in isoprene emissions. Integration of leaf gas-exchange, isoprene emissions, proteomics, and respiratory thermotolerance measurements provided new insight into mechanisms underlying variability in tree species heatwave tolerance. Importantly, warm-grown seedlings were, surprisingly, more susceptible to heatwave damage than cool-grown seedlings, which could be associated with reduced enzyme concentrations in leaves. We conclude that species with restricted range sizes, along with trees growing under climate warming, may be more vulnerable to heatwaves of the future.
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Affiliation(s)
- Michael J Aspinwall
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
- Department of Biology, University of North Florida, Jacksonville, Florida
| | - Sebastian Pfautsch
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
| | - Mark G Tjoelker
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
| | - Angelica Vårhammar
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
| | - Malcolm Possell
- School of Life and Environmental Sciences, University of Sydney, Sydney, NSW, Australia
| | - John E Drake
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
- Forest and Natural Resources Management, SUNY-ESF, Syracuse, New York
| | - Peter B Reich
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
- Department of Forest Resources, University of Minnesota, Minnesota
| | - David T Tissue
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
| | - Owen K Atkin
- Division of Plant Sciences, Research School of Biology, The Australian National University, Canberra, ACT, Australia
| | - Paul D Rymer
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
| | - Siobhan Dennison
- Department of Biological Science, Macquarie University, North Ryde, NSW, Australia
| | - Steven C Van Sluyter
- Department of Biological Science, Macquarie University, North Ryde, NSW, Australia
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9
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Keenan TF, Migliavacca M, Papale D, Baldocchi D, Reichstein M, Torn M, Wutzler T. Widespread inhibition of daytime ecosystem respiration. Nat Ecol Evol 2019; 3:407-415. [PMID: 30742107 PMCID: PMC6421340 DOI: 10.1038/s41559-019-0809-2] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Accepted: 12/12/2018] [Indexed: 11/22/2022]
Abstract
The global land surface absorbs about a third of anthropogenic emissions each year, due to the difference between two key processes: ecosystem photosynthesis and respiration. Despite the importance of these two processes, it is not possible to measure either at the ecosystem scale during the daytime. Eddy-covariance measurements are widely used as the closest 'quasi-direct' ecosystem-scale observation from which to estimate ecosystem photosynthesis and respiration. Recent research, however, suggests that current estimates may be biased by up to 25%, due to a previously unaccounted for process: the inhibition of leaf respiration in the light. Yet the extent of inhibition remains debated, and implications for estimates of ecosystem-scale respiration and photosynthesis remain unquantified. Here, we quantify an apparent inhibition of daytime ecosystem respiration across the global FLUXNET eddy-covariance network and identify a pervasive influence that varies by season and ecosystem type. We develop partitioning methods that can detect an apparent ecosystem-scale inhibition of daytime respiration and find that diurnal patterns of ecosystem respiration might be markedly different than previously thought. The results call for the re-evaluation of global terrestrial carbon cycle models and also suggest that current global estimates of photosynthesis and respiration may be biased, some on the order of magnitude of anthropogenic fossil fuel emissions.
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Affiliation(s)
- Trevor F Keenan
- Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
- UC Berkeley, Berkeley, CA, USA.
| | | | - Dario Papale
- University of Tuscia, Viterbo, Italy
- Euro-Mediterranean Centre on Climate Change, Viterbo, Italy
| | | | | | - Margaret Torn
- Lawrence Berkeley National Laboratory, Berkeley, CA, USA
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10
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Dusenge ME, Duarte AG, Way DA. Plant carbon metabolism and climate change: elevated CO 2 and temperature impacts on photosynthesis, photorespiration and respiration. THE NEW PHYTOLOGIST 2019; 221:32-49. [PMID: 29983005 DOI: 10.1111/nph.15283] [Citation(s) in RCA: 297] [Impact Index Per Article: 59.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 05/11/2018] [Indexed: 05/18/2023]
Abstract
Contents Summary 32 I. The importance of plant carbon metabolism for climate change 32 II. Rising atmospheric CO2 and carbon metabolism 33 III. Rising temperatures and carbon metabolism 37 IV. Thermal acclimation responses of carbon metabolic processes can be best understood when studied together 38 V. Will elevated CO2 offset warming-induced changes in carbon metabolism? 40 VI. No plant is an island: water and nutrient limitations define plant responses to climate drivers 41 VII. Conclusions 42 Acknowledgements 42 References 42 Appendix A1 48 SUMMARY: Plant carbon metabolism is impacted by rising CO2 concentrations and temperatures, but also feeds back onto the climate system to help determine the trajectory of future climate change. Here we review how photosynthesis, photorespiration and respiration are affected by increasing atmospheric CO2 concentrations and climate warming, both separately and in combination. We also compile data from the literature on plants grown at multiple temperatures, focusing on net CO2 assimilation rates and leaf dark respiration rates measured at the growth temperature (Agrowth and Rgrowth , respectively). Our analyses show that the ratio of Agrowth to Rgrowth is generally homeostatic across a wide range of species and growth temperatures, and that species that have reduced Agrowth at higher growth temperatures also tend to have reduced Rgrowth , while species that show stimulations in Agrowth under warming tend to have higher Rgrowth in the hotter environment. These results highlight the need to study these physiological processes together to better predict how vegetation carbon metabolism will respond to climate change.
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Affiliation(s)
- Mirindi Eric Dusenge
- Department of Biology, University of Western Ontario, London, ON, N6A 5B7, Canada
| | - André Galvao Duarte
- Department of Biology, University of Western Ontario, London, ON, N6A 5B7, Canada
| | - Danielle A Way
- Department of Biology, University of Western Ontario, London, ON, N6A 5B7, Canada
- Nicholas School of the Environment, Duke University, Durham, NC, 27708, USA
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11
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Patterson AE, Arkebauer R, Quallo C, Heskel MA, Li X, Boelman N, Griffin KL. Temperature response of respiration and respiratory quotients of 16 co-occurring temperate tree species. TREE PHYSIOLOGY 2018; 38:1319-1332. [PMID: 29425346 DOI: 10.1093/treephys/tpx176] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 12/29/2017] [Indexed: 05/05/2023]
Abstract
The forests of the northeastern US are globally, one of the fastest growing terrestrial carbon sinks due to historical declines in large-scale agriculture, timber harvesting and fire disturbance. However, shifting range distributions of tree species with warming air temperatures are altering forest community composition and carbon dynamics. Here, we focus on respiration, a physiological process that is strongly temperature and species dependent. We specifically examined the response of respiration (R; CO2 release) to temperature in 10 broadleaved and six conifer species, as well as the respiratory quotient (RQ; ratio of CO2 released to O2 consumed) of nine broadleaved species that co-occur in the Hudson Highlands Region of New York, USA. The relationships between these physiological measurements and associated leaf traits were also explored. The rates of respiration at 20 °C were 71% higher in northern-ranged broadleaved species when compared with both central- and southern-ranged species. In contrast, the rates of respiration at 20 °C in northern-ranged conifers were 12% lower than in central-ranged conifers. The RQ of broadleaved species increased by 14% as temperatures increased from 15 °C to 35 °C. When RQ values were pooled across temperature, northern-ranged broadleaved species had 12% and 9% lower RQ values than central, and southern-ranged species, respectively, suggesting a reliance on alternative (non-carbohydrate) substrates to fulfill respiratory demands. A Pearson correlation analysis of leaf traits and respiration revealed strong correlations between leaf nitrogen, leaf mass area and R for both broadleaved and conifer species. Our results elucidate leaf trait relationships with tree physiology and reveal the various form and function strategies for species from differing range distributions. Compounded with predicted range distribution shifts and species replacement, this may reduce the carbon storage potential of northeast forests.
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Affiliation(s)
- Angelica E Patterson
- Columbia University, Department of Earth and Environmental Sciences, 5th Fl Schermerhorn Extension, 1200 Amsterdam Ave., New York, NY, USA
- Lamont-Doherty Earth Observatory, Columbia University, 61 Route 9W, Palisades, NY, USA
| | - Rachel Arkebauer
- Columbia University, Ecology Evolution and Environmental Biology Department, 10th Fl Schermerhorn Extension, 1200 Amsterdam Ave., New York, NY, USA
| | - Crystal Quallo
- Columbia University, Barnard College, Department of Environmental Sciences, 3009 Broadway, 4th Fl Altschul Hall, New York, NY, USA
| | - Mary A Heskel
- The Ecosystems Center, Marine Biological Laboratory, Woods Hole, MA, USA
| | - Ximeng Li
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW, Australia
| | - Natalie Boelman
- Lamont-Doherty Earth Observatory, Columbia University, 61 Route 9W, Palisades, NY, USA
| | - Kevin L Griffin
- Columbia University, Department of Earth and Environmental Sciences, 5th Fl Schermerhorn Extension, 1200 Amsterdam Ave., New York, NY, USA
- Lamont-Doherty Earth Observatory, Columbia University, 61 Route 9W, Palisades, NY, USA
- Columbia University, Ecology Evolution and Environmental Biology Department, 10th Fl Schermerhorn Extension, 1200 Amsterdam Ave., New York, NY, USA
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12
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Crous KY, Wallin G, Atkin OK, Uddling J, Af Ekenstam A. Acclimation of light and dark respiration to experimental and seasonal warming are mediated by changes in leaf nitrogen in Eucalyptus globulus. TREE PHYSIOLOGY 2017; 37:1069-1083. [PMID: 28541536 DOI: 10.1093/treephys/tpx052] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Accepted: 05/10/2017] [Indexed: 06/07/2023]
Abstract
Quantifying the adjustments of leaf respiration in response to seasonal temperature variation and climate warming is crucial because carbon loss from vegetation is a large but uncertain part of the global carbon cycle. We grew fast-growing Eucalyptus globulus Labill. trees exposed to +3 °C warming and elevated CO2 in 10-m tall whole-tree chambers and measured the temperature responses of leaf mitochondrial respiration, both in light (RLight) and in darkness (RDark), over a 20-40 °C temperature range and during two different seasons. RLight was assessed using the Laisk method. Respiration rates measured at a standard temperature (25 °C - R25) were higher in warm-grown trees and in the warm season, related to higher total leaf nitrogen (N) investment with higher temperatures (both experimental and seasonal), indicating that leaf N concentrations modulated the respiratory capacity to changes in temperature. Once differences in leaf N were accounted for, there were no differences in R25 but the Q10 (i.e., short-term temperature sensitivity) was higher in late summer compared with early spring. The variation in RLight between experimental treatments and seasons was positively correlated with carboxylation capacity and photorespiration. RLight was less responsive to short-term changes in temperature than RDark, as shown by a lower Q10 in RLight compared with RDark. The overall light inhibition of R was ∼40%. Our results highlight the dynamic nature of leaf respiration to temperature variation and that the responses of RLight do not simply mirror those of RDark. Therefore, it is important not to assume that RLight is the same as RDark in ecosystem models, as doing so may lead to large errors in predicting plant CO2 release and productivity.
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Affiliation(s)
- K Y Crous
- Hawkesbury Institute for Environment, Western Sydney University, Hawkesbury Campus, Locked Bag 1797, Penrith, NSW 2751, Australia
| | - G Wallin
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 461, SE-40530 Gothenburg, Sweden
| | - O K Atkin
- ARC Centre of Excellence in Plant Energy Biology, Division of Plant Sciences, Research School of Biology, Building 134, The Australian National University, Canberra, ACT 2601, Australia
| | - J Uddling
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 461, SE-40530 Gothenburg, Sweden
| | - A Af Ekenstam
- Hawkesbury Institute for Environment, Western Sydney University, Hawkesbury Campus, Locked Bag 1797, Penrith, NSW 2751, Australia
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 461, SE-40530 Gothenburg, Sweden
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13
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Wei X, Sendall KM, Stefanski A, Zhao C, Hou J, Rich RL, Montgomery RA, Reich PB. Consistent leaf respiratory response to experimental warming of three North American deciduous trees: a comparison across seasons, years, habitats and sites. TREE PHYSIOLOGY 2017; 37:285-300. [PMID: 27974651 DOI: 10.1093/treephys/tpw112] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Accepted: 10/01/2016] [Indexed: 06/06/2023]
Abstract
Most vascular plants acclimate respiration to changes in ambient temperature, but explicit tests of these responses in field settings are rare, and how acclimation responses vary in space and time is relatively unstudied, hindering our ability to predict respiratory release of carbon under future climatic conditions. We measured temperature response curves of leaf respiration for three deciduous tree species from 2009 to 2012 in a field warming experiment (+3.4 °C above ambient) in both open and understory conditions at two sites in the southern boreal forest in Minnesota, USA. We analyzed the effects of warming on leaf respiration, and how the effects varied among species, times of season (early, middle and late parts of the growing season), sites, habitats (understory, open) and years. We hypothesized that the respiration exponent (Q10) of the short-term temperature response curve and the degree of acclimation would be smaller under conditions where plants were more likely to be substrate limited, such as in the understory or the margins of the growing season. However, in contrast to these predictions, stable Q10 and strong respiratory acclimation were consistently observed. For each species, the Q10 did not vary with experimental warming, nor was its response to warming influenced by time of season, year, site or habitat. Strong leaf respiratory acclimation to warming occurred in each species and was consistent across most sources of variation. Most of the leaf traits studied were not affected by warming, while the Q10-leaf nitrogen and R25-soluble carbohydrate relationships were observed, and shifted with warming, implying that acclimation may be associated with the adjustment in respiratory capacity and its relation to leaf nitrogen and soluble carbohydrate content. Consistent Q10 and acclimation across habitats, sites, times of season and years suggest that modeling of temperature acclimation may be possible with relatively simple functions.
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Affiliation(s)
- Xiaorong Wei
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, Xinong Road 26, Yangling 712100, China
- Department of Forest Resources, University of Minnesota, 1530 Cleveland Avenue N, St Paul, MN 55108, USA
| | - Kerrie M Sendall
- Department of Forest Resources, University of Minnesota, 1530 Cleveland Avenue N, St Paul, MN 55108, USA
| | - Artur Stefanski
- Department of Forest Resources, University of Minnesota, 1530 Cleveland Avenue N, St Paul, MN 55108, USA
| | - Changming Zhao
- State Key Laboratory of Grassland Agro-Ecosystems, School of Life Sciences, South Tianshui Road 222, Lanzhou University, Lanzhou 730000, China
| | - Jihua Hou
- Key Laboratory for Forest Resources & Ecosystem Processes of Beijing, Beijing Forestry University, East Qinghua Road 35, Beijing 100083, China
| | - Roy L Rich
- Department of Forest Resources, University of Minnesota, 1530 Cleveland Avenue N, St Paul, MN 55108, USA
| | - Rebecca A Montgomery
- Department of Forest Resources, University of Minnesota, 1530 Cleveland Avenue N, St Paul, MN 55108, USA
| | - Peter B Reich
- Department of Forest Resources, University of Minnesota, 1530 Cleveland Avenue N, St Paul, MN 55108, USA
- Hawkesbury Institute for the Environment, University of Western Sydney, Penrith, NSW 2753, Australia
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14
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O'sullivan OS, Heskel MA, Reich PB, Tjoelker MG, Weerasinghe LK, Penillard A, Zhu L, Egerton JJG, Bloomfield KJ, Creek D, Bahar NHA, Griffin KL, Hurry V, Meir P, Turnbull MH, Atkin OK. Thermal limits of leaf metabolism across biomes. GLOBAL CHANGE BIOLOGY 2017; 23:209-223. [PMID: 27562605 DOI: 10.1111/gcb.13477] [Citation(s) in RCA: 117] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2016] [Revised: 07/29/2016] [Accepted: 08/13/2016] [Indexed: 05/24/2023]
Abstract
High-temperature tolerance in plants is important in a warming world, with extreme heat waves predicted to increase in frequency and duration, potentially leading to lethal heating of leaves. Global patterns of high-temperature tolerance are documented in animals, but generally not in plants, limiting our ability to assess risks associated with climate warming. To assess whether there are global patterns in high-temperature tolerance of leaf metabolism, we quantified Tcrit (high temperature where minimal chlorophyll a fluorescence rises rapidly and thus photosystem II is disrupted) and Tmax (temperature where leaf respiration in darkness is maximal, beyond which respiratory function rapidly declines) in upper canopy leaves of 218 plant species spanning seven biomes. Mean site-based Tcrit values ranged from 41.5 °C in the Alaskan arctic to 50.8 °C in lowland tropical rainforests of Peruvian Amazon. For Tmax , the equivalent values were 51.0 and 60.6 °C in the Arctic and Amazon, respectively. Tcrit and Tmax followed similar biogeographic patterns, increasing linearly (˜8 °C) from polar to equatorial regions. Such increases in high-temperature tolerance are much less than expected based on the 20 °C span in high-temperature extremes across the globe. Moreover, with only modest high-temperature tolerance despite high summer temperature extremes, species in mid-latitude (~20-50°) regions have the narrowest thermal safety margins in upper canopy leaves; these regions are at the greatest risk of damage due to extreme heat-wave events, especially under conditions when leaf temperatures are further elevated by a lack of transpirational cooling. Using predicted heat-wave events for 2050 and accounting for possible thermal acclimation of Tcrit and Tmax , we also found that these safety margins could shrink in a warmer world, as rising temperatures are likely to exceed thermal tolerance limits. Thus, increasing numbers of species in many biomes may be at risk as heat-wave events become more severe with climate change.
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Affiliation(s)
- Odhran S O'sullivan
- Division of Plant Sciences, Research School of Biology, The Australian National University, Building 46, Canberra, ACT, 2601, Australia
- Department of Animal and Plant Sciences, University of Sheffield, Alfred Denny Building, Western Bank, Sheffield, S10 2TN, UK
| | - Mary A Heskel
- Division of Plant Sciences, Research School of Biology, The Australian National University, Building 46, Canberra, ACT, 2601, Australia
- The Ecosystems Center, Marine Biological Laboratory, Woods Hole, MA, 02544, USA
| | - Peter B Reich
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, 2751, Australia
- Department of Forest Resources, University of Minnesota, 1530 Cleveland Avenue North, St. Paul, MN, 55108, USA
| | - Mark G Tjoelker
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, 2751, Australia
| | - Lasantha K Weerasinghe
- Division of Plant Sciences, Research School of Biology, The Australian National University, Building 46, Canberra, ACT, 2601, Australia
- Faculty of Agriculture, University of Peradeniya, Peradeniya, 20400, Sri Lanka
| | - Aurore Penillard
- Division of Plant Sciences, Research School of Biology, The Australian National University, Building 46, Canberra, ACT, 2601, Australia
| | - Lingling Zhu
- Division of Plant Sciences, Research School of Biology, The Australian National University, Building 46, Canberra, ACT, 2601, Australia
- ARC Centre of Excellence in Plant Energy Biology, Research School of Biology, The Australian National University, Building 134, Canberra, ACT, 2601, Australia
| | - John J G Egerton
- Division of Plant Sciences, Research School of Biology, The Australian National University, Building 46, Canberra, ACT, 2601, Australia
| | - Keith J Bloomfield
- Division of Plant Sciences, Research School of Biology, The Australian National University, Building 46, Canberra, ACT, 2601, Australia
| | - Danielle Creek
- Division of Plant Sciences, Research School of Biology, The Australian National University, Building 46, Canberra, ACT, 2601, Australia
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, 2751, Australia
| | - Nur H A Bahar
- Division of Plant Sciences, Research School of Biology, The Australian National University, Building 46, Canberra, ACT, 2601, Australia
- ARC Centre of Excellence in Plant Energy Biology, Research School of Biology, The Australian National University, Building 134, Canberra, ACT, 2601, Australia
| | - Kevin L Griffin
- Department of Earth and Environment Sciences, Columbia University, Palisades, NY, 10964, USA
| | - Vaughan Hurry
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå, SE-901 84, Sweden
| | - Patrick Meir
- Division of Plant Sciences, Research School of Biology, The Australian National University, Building 46, Canberra, ACT, 2601, Australia
- School of Geosciences, University of Edinburgh, Edinburgh, EH9 3FF, UK
| | - Matthew H Turnbull
- Centre for Integrative Ecology, School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch, New Zealand
| | - Owen K Atkin
- Division of Plant Sciences, Research School of Biology, The Australian National University, Building 46, Canberra, ACT, 2601, Australia
- ARC Centre of Excellence in Plant Energy Biology, Research School of Biology, The Australian National University, Building 134, Canberra, ACT, 2601, Australia
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15
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Convergence in the temperature response of leaf respiration across biomes and plant functional types. Proc Natl Acad Sci U S A 2016; 113:3832-7. [PMID: 27001849 DOI: 10.1073/pnas.1520282113] [Citation(s) in RCA: 128] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Plant respiration constitutes a massive carbon flux to the atmosphere, and a major control on the evolution of the global carbon cycle. It therefore has the potential to modulate levels of climate change due to the human burning of fossil fuels. Neither current physiological nor terrestrial biosphere models adequately describe its short-term temperature response, and even minor differences in the shape of the response curve can significantly impact estimates of ecosystem carbon release and/or storage. Given this, it is critical to establish whether there are predictable patterns in the shape of the respiration-temperature response curve, and thus in the intrinsic temperature sensitivity of respiration across the globe. Analyzing measurements in a comprehensive database for 231 species spanning 7 biomes, we demonstrate that temperature-dependent increases in leaf respiration do not follow a commonly used exponential function. Instead, we find a decelerating function as leaves warm, reflecting a declining sensitivity to higher temperatures that is remarkably uniform across all biomes and plant functional types. Such convergence in the temperature sensitivity of leaf respiration suggests that there are universally applicable controls on the temperature response of plant energy metabolism, such that a single new function can predict the temperature dependence of leaf respiration for global vegetation. This simple function enables straightforward description of plant respiration in the land-surface components of coupled earth system models. Our cross-biome analyses shows significant implications for such fluxes in cold climates, generally projecting lower values compared with previous estimates.
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16
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Noguchi K, Yamori W, Hikosaka K, Terashima I. Homeostasis of the temperature sensitivity of respiration over a range of growth temperatures indicated by a modified Arrhenius model. THE NEW PHYTOLOGIST 2015; 207:34-42. [PMID: 25704334 DOI: 10.1111/nph.13339] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Accepted: 01/23/2015] [Indexed: 05/24/2023]
Abstract
The temperature dependence of plant respiratory rate (R) changes in response to growth temperature. Here, we used a modified Arrhenius model incorporating the temperature dependence of activation energy (Eo ), and compared the temperature dependence of R between cold-sensitive and cold-tolerant species. We analyzed the temperature dependences of leaf CO2 efflux rate of plants cultivated at low (LT) or high temperature (HT). In plants grown at HT (HT plants), Eo at low measurement temperature varied among species, but Eo at growth temperature in HT plants did not vary and was comparable to that in plants grown at LT (LT plants), suggesting that the limiting process was similar at the respective growth temperatures. In LT plants, the integrated value of loge R, a measure of respiratory capacity, in cold-sensitive species was lower than that in cold-tolerant species. When plants were transferred from HT to LT, the respiratory capacity changed promptly after the transfer compared with the other parameters. These results suggest that a similar process limits R at different growth temperatures, and that the lower capacity of the respiratory system in cold-sensitive species may explain their low growth rate at LT.
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Affiliation(s)
- Ko Noguchi
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Wataru Yamori
- Center for Environment, Health and Field Sciences, Chiba University, Kashiwa, Chiba, Japan
- PREST, JST, 332-0012, Japan
| | - Kouki Hikosaka
- Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi, Japan
- CREST, JST, 332-0012, Japan
| | - Ichiro Terashima
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
- CREST, JST, 332-0012, Japan
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17
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Way DA, Oren R, Kroner Y. The space-time continuum: the effects of elevated CO2 and temperature on trees and the importance of scaling. PLANT, CELL & ENVIRONMENT 2015; 38:991-1007. [PMID: 25737035 DOI: 10.1111/pce.12527] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Revised: 01/15/2015] [Accepted: 02/17/2015] [Indexed: 05/27/2023]
Abstract
To predict how forests will respond to rising temperatures and atmospheric CO₂ concentrations, we need to understand how trees respond to both of these environmental factors. In this review, we discuss the importance of scaling, moving from leaf-level responses to those of the canopy, and from short-term to long-term responses of vegetation to climate change. While our knowledge of leaf-level, instantaneous responses of photosynthesis, respiration, stomatal conductance, transpiration and water-use efficiency to elevated CO₂ and temperature is quite good, our ability to scale these responses up to larger spatial and temporal scales is less developed. We highlight which physiological processes are least understood at various levels of study, and discuss how ignoring differences in the spatial or temporal scale of a physiological process impedes our ability to predict how forest carbon and water fluxes forests will be altered in the future. We also synthesize data from the literature to show that light respiration follows a generalized temperature response across studies, and that the light compensation point of photosynthesis is reduced by elevated growth CO₂. Lastly, we emphasize the need to move beyond single factorial experiments whenever possible, and to combine both CO₂ and temperature treatments in studies of tree performance.
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Affiliation(s)
- Danielle A Way
- Department of Biology, University of Western Ontario, London, ON, N6A 5B7, Canada; Nicholas School of the Environment, Duke University, Durham, NC, 27708, USA
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18
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Gauthier PPG, Crous KY, Ayub G, Duan H, Weerasinghe LK, Ellsworth DS, Tjoelker MG, Evans JR, Tissue DT, Atkin OK. Drought increases heat tolerance of leaf respiration in Eucalyptus globulus saplings grown under both ambient and elevated atmospheric [CO2] and temperature. JOURNAL OF EXPERIMENTAL BOTANY 2014; 65:6471-85. [PMID: 25205579 PMCID: PMC4246183 DOI: 10.1093/jxb/eru367] [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: 05/19/2023]
Abstract
Climate change is resulting in increasing atmospheric [CO2], rising growth temperature (T), and greater frequency/severity of drought, with each factor having the potential to alter the respiratory metabolism of leaves. Here, the effects of elevated atmospheric [CO2], sustained warming, and drought on leaf dark respiration (R(dark)), and the short-term T response of R(dark) were examined in Eucalyptus globulus. Comparisons were made using seedlings grown under different [CO2], T, and drought treatments. Using high resolution T-response curves of R(dark) measured over the 15-65 °C range, it was found that elevated [CO2], elevated growth T, and drought had little effect on rates of R(dark) measured at T <35 °C and that there was no interactive effect of [CO2], growth T, and drought on T response of R(dark). However, drought increased R(dark) at high leaf T typical of heatwave events (35-45 °C), and increased the measuring T at which maximal rates of R(dark) occurred (Tmax) by 8 °C (from 52 °C in well-watered plants to 60 °C in drought-treated plants). Leaf starch and soluble sugars decreased under drought and elevated growth T, respectively, but no effect was found under elevated [CO2]. Elevated [CO2] increased the Q 10 of R(dark) (i.e. proportional rise in R(dark) per 10 °C) over the 15-35 °C range, while drought increased Q 10 values between 35 °C and 45 °C. Collectively, the study highlights the dynamic nature of the T dependence of R dark in plants experiencing future climate change scenarios, particularly with respect to drought and elevated [CO2].
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Affiliation(s)
- Paul P G Gauthier
- Division of Plant Sciences, Research School of Biology, Building 46, The Australian National University, Canberra, ACT, 0200, Australia Department of Geosciences, Princeton University, Guyot Hall, Princeton, NJ 08544, USA
| | - Kristine Y Crous
- Division of Plant Sciences, Research School of Biology, Building 46, The Australian National University, Canberra, ACT, 0200, Australia Hawkesbury Institute for the Environment, University of Western Sydney, Hawkesbury Campus, Locked Bag 1797, Penrith, NSW, 2751, Australia
| | - Gohar Ayub
- Division of Plant Sciences, Research School of Biology, Building 46, The Australian National University, Canberra, ACT, 0200, Australia Department of Horticulture, Agricultural University Peshawar, 25130, Khyber Pakhtunkhwa, Pakistan
| | - Honglang Duan
- Hawkesbury Institute for the Environment, University of Western Sydney, Hawkesbury Campus, Locked Bag 1797, Penrith, NSW, 2751, Australia Institute of Ecology & Environmental Science, Nanchang Institute of Technology, No. 289 Tianxiang Road, Nanchang 330099, China
| | - Lasantha K Weerasinghe
- Division of Plant Sciences, Research School of Biology, Building 46, The Australian National University, Canberra, ACT, 0200, Australia Faculty of Agriculture, University of Peradeniya, Peradeniya, 20400, Sri Lanka
| | - David S Ellsworth
- Hawkesbury Institute for the Environment, University of Western Sydney, Hawkesbury Campus, Locked Bag 1797, Penrith, NSW, 2751, Australia
| | - Mark G Tjoelker
- Hawkesbury Institute for the Environment, University of Western Sydney, Hawkesbury Campus, Locked Bag 1797, Penrith, NSW, 2751, Australia
| | - John R Evans
- Division of Plant Sciences, Research School of Biology, Building 46, The Australian National University, Canberra, ACT, 0200, Australia
| | - David T Tissue
- Hawkesbury Institute for the Environment, University of Western Sydney, Hawkesbury Campus, Locked Bag 1797, Penrith, NSW, 2751, Australia
| | - Owen K Atkin
- Division of Plant Sciences, Research School of Biology, Building 46, The Australian National University, Canberra, ACT, 0200, Australia ARC Centre of Excellence in Plant Energy Biology, The Australian National University, Canberra, ACT, 0200, Australia
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