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Herol L, Avidar M, Yirmiahu S, Zach YY, Klein T, Shemesh H, Livne-Luzon S. Context-dependent benefits of forest soil addition on Aleppo pine seedling performance under drought and grass competition. MYCORRHIZA 2024; 34:217-227. [PMID: 38762648 PMCID: PMC11166812 DOI: 10.1007/s00572-024-01151-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Accepted: 04/30/2024] [Indexed: 05/20/2024]
Abstract
Seedling establishment under natural conditions is limited by numerous interacting factors. Here, we tested the combined effects of drought, herbaceous competition, and ectomycorrhizal inoculation on the performance of Aleppo pine seedlings grown in a net-house. The roots of all pine seedlings were strongly dominated by Geopora, a fungal genus known to colonize seedlings in dry habitats. Ectomycorrhizal fungi (EMF) inoculum significantly increased seedling height, biomass, and the number of side branches. However, under either competition or drought, the positive effect of EMF on seedling biomass and height was greatly reduced, while the effect on shoot branching was maintained. Further, under a combination of drought and competition, EMF had no influence on either plant growth or shape. The discrepancy in pine performance across treatments highlights the complexity of benefits provided to seedlings by EMF under ecologically relevant settings.
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Affiliation(s)
- Lior Herol
- Department of Environmental Sciences, Tel-Hai College, Qiryat Shemona, Israel
| | - Mor Avidar
- Department of Environmental Sciences, Tel-Hai College, Qiryat Shemona, Israel
| | - Shahar Yirmiahu
- Department of Environmental Sciences, Tel-Hai College, Qiryat Shemona, Israel
| | - Yair Yehoshua Zach
- Department of Environmental Sciences, Tel-Hai College, Qiryat Shemona, Israel
| | - Tamir Klein
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Hagai Shemesh
- Department of Environmental Sciences, Tel-Hai College, Qiryat Shemona, Israel
| | - Stav Livne-Luzon
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel.
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2
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Gao D, Luster J, Zürcher A, Arend M, Bai E, Gessler A, Rigling A, Schaub M, Hartmann M, Werner RA, Joseph J, Poll C, Hagedorn F. Drought resistance and resilience of rhizosphere communities in forest soils from the cellular to ecosystem scale - insights from 13C pulse labeling. THE NEW PHYTOLOGIST 2024; 242:960-974. [PMID: 38402527 DOI: 10.1111/nph.19612] [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: 12/01/2023] [Accepted: 02/06/2024] [Indexed: 02/26/2024]
Abstract
The link between above- and belowground communities is a key uncertainty in drought and rewetting effects on forest carbon (C) cycle. In young beech model ecosystems and mature naturally dry pine forest exposed to 15-yr-long irrigation, we performed 13C pulse labeling experiments, one during drought and one 2 wk after rewetting, tracing tree assimilates into rhizosphere communities. The 13C pulses applied in tree crowns reached soil microbial communities of the young and mature forests one and 4 d later, respectively. Drought decreased the transfer of labeled assimilates relative to the irrigation treatment. The 13C label in phospholipid fatty acids (PLFAs) indicated greater drought reduction of assimilate incorporation by fungi (-85%) than by gram-positive (-43%) and gram-negative bacteria (-58%). 13C label incorporation was more strongly reduced for PLFAs (cell membrane) than for microbial cytoplasm extracted by chloroform. This suggests that fresh rhizodeposits are predominantly used for osmoregulation or storage under drought, at the expense of new cell formation. Two weeks after rewetting, 13C enrichment in PLFAs was greater in previously dry than in continuously moist soils. Drought and rewetting effects were greater in beech systems than in pine forest. Belowground C allocation and rhizosphere communities are highly resilient to drought.
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Affiliation(s)
- Decai Gao
- Swiss Federal Institute for Forest, Snow and Landscape Research, 8903, Birmensdorf, Switzerland
- Qianyanzhou Ecological Research Station, Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101, Beijing, China
- College of Resources and Environment, University of Chinese Academy of Sciences, 100190, Beijing, China
| | - Jörg Luster
- Swiss Federal Institute for Forest, Snow and Landscape Research, 8903, Birmensdorf, Switzerland
| | - Alois Zürcher
- Swiss Federal Institute for Forest, Snow and Landscape Research, 8903, Birmensdorf, Switzerland
| | - Matthias Arend
- Swiss Federal Institute for Forest, Snow and Landscape Research, 8903, Birmensdorf, Switzerland
- Physiological Plant Ecology, University of Basel, 4056, Basel, Switzerland
| | - Edith Bai
- Key Laboratory of Geographical Processes and Ecological Security of Changbai Mountains, Ministry of Education, Northeast Normal University, 130024, Changchun, China
| | - Arthur Gessler
- Swiss Federal Institute for Forest, Snow and Landscape Research, 8903, Birmensdorf, Switzerland
- Terrestrial Ecosystems, ETH Zürich, 8092, Zürich, Switzerland
| | - Andreas Rigling
- Swiss Federal Institute for Forest, Snow and Landscape Research, 8903, Birmensdorf, Switzerland
- Terrestrial Ecosystems, ETH Zürich, 8092, Zürich, Switzerland
| | - Marcus Schaub
- Swiss Federal Institute for Forest, Snow and Landscape Research, 8903, Birmensdorf, Switzerland
| | - Martin Hartmann
- Sustainable Agroecosystems Group, Department of Environmental Systems Science, Institute of Agricultural Sciences, ETH Zürich, 8092, Zürich, Switzerland
| | - Roland A Werner
- Agricultural Sciences, ETH Zürich, 8092, Zürich, Switzerland
| | - Jobin Joseph
- Swiss Federal Institute for Forest, Snow and Landscape Research, 8903, Birmensdorf, Switzerland
| | - Christian Poll
- Soil Biology, University of Hohenheim, 70599, Stuttgart, Germany
| | - Frank Hagedorn
- Swiss Federal Institute for Forest, Snow and Landscape Research, 8903, Birmensdorf, Switzerland
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3
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Gessler A, Zweifel R. Beyond source and sink control - toward an integrated approach to understand the carbon balance in plants. THE NEW PHYTOLOGIST 2024; 242:858-869. [PMID: 38375596 DOI: 10.1111/nph.19611] [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: 10/10/2023] [Accepted: 02/03/2024] [Indexed: 02/21/2024]
Abstract
A conceptual understanding on how the vegetation's carbon (C) balance is determined by source activity and sink demand is important to predict its C uptake and sequestration potential now and in the future. We have gathered trajectories of photosynthesis and growth as a function of environmental conditions described in the literature and compared them with current concepts of source and sink control. There is no clear evidence for pure source or sink control of the C balance, which contradicts recent hypotheses. Using model scenarios, we show how legacy effects via structural and functional traits and antecedent environmental conditions can alter the plant's carbon balance. We, thus, combined the concept of short-term source-sink coordination with long-term environmentally driven legacy effects that dynamically acclimate structural and functional traits over time. These acclimated traits feedback on the sensitivity of source and sink activity and thus change the plant physiological responses to environmental conditions. We postulate a whole plant C-coordination system that is primarily driven by stomatal optimization of growth to avoid a C source-sink mismatch. Therefore, we anticipate that C sequestration of forest ecosystems under future climate conditions will largely follow optimality principles that balance water and carbon resources to maximize growth in the long term.
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Affiliation(s)
- Arthur Gessler
- Swiss Federal Research Institute WSL, 8903, Birmensdorf, Switzerland
- Institute of Terrestrial Ecosystems, ETH Zurich, 8092, Zurich, Switzerland
| | - Roman Zweifel
- Swiss Federal Research Institute WSL, 8903, Birmensdorf, Switzerland
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4
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Huang J, Ladd SN, Ingrisch J, Kübert A, Meredith LK, van Haren J, Bamberger I, Daber LE, Kühnhammer K, Bailey K, Hu J, Fudyma J, Shi L, Dippold MA, Meeran K, Miller L, O'Brien MJ, Yang H, Herrera-Ramírez D, Hartmann H, Trumbore S, Bahn M, Werner C, Lehmann MM. The mobilization and transport of newly fixed carbon are driven by plant water use in an experimental rainforest under drought. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:2545-2557. [PMID: 38271585 DOI: 10.1093/jxb/erae030] [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: 08/21/2023] [Accepted: 01/24/2024] [Indexed: 01/27/2024]
Abstract
Non-structural carbohydrates (NSCs) are building blocks for biomass and fuel metabolic processes. However, it remains unclear how tropical forests mobilize, export, and transport NSCs to cope with extreme droughts. We combined drought manipulation and ecosystem 13CO2 pulse-labeling in an enclosed rainforest at Biosphere 2, assessed changes in NSCs, and traced newly assimilated carbohydrates in plant species with diverse hydraulic traits and canopy positions. We show that drought caused a depletion of leaf starch reserves and slowed export and transport of newly assimilated carbohydrates below ground. Drought effects were more pronounced in conservative canopy trees with limited supply of new photosynthates and relatively constant water status than in those with continual photosynthetic supply and deteriorated water status. We provide experimental evidence that local utilization, export, and transport of newly assimilated carbon are closely coupled with plant water use in canopy trees. We highlight that these processes are critical for understanding and predicting tree resistance and ecosystem fluxes in tropical forest under drought.
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Affiliation(s)
- Jianbei Huang
- Max Planck Institute for Biogeochemistry, D-07745 Jena, Germany
| | - S Nemiah Ladd
- Ecosystem Physiology, Albert-Ludwig-University of Freiburg, Freiburg, Germany
- Department of Environmental Sciences, University of Basel, Bernoullistrasse 30, 4056 Basel, Switzerland
| | - Johannes Ingrisch
- Ecosystem Physiology, Albert-Ludwig-University of Freiburg, Freiburg, Germany
- Department of Ecology, University of Innsbruck, Sternwartestr 15, 6020 Innsbruck, Austria
| | - Angelika Kübert
- Ecosystem Physiology, Albert-Ludwig-University of Freiburg, Freiburg, Germany
| | - Laura K Meredith
- School of Natural Resources and the Environment, University of Arizona, 1064 E. Lowell St., Tucson, AZ 85721, USA
- Biosphere 2, University of Arizona, 32540 S. Biosphere Rd, Oracle, AZ 85739, USA
| | - Joost van Haren
- Biosphere 2, University of Arizona, 32540 S. Biosphere Rd, Oracle, AZ 85739, USA
- Honors College, University of Arizona, 1101 East Mabel Street, Tucson, AZ 85719, USA
| | - Ines Bamberger
- Ecosystem Physiology, Albert-Ludwig-University of Freiburg, Freiburg, Germany
- Atmospheric Chemistry Group, University of Bayreuth (BayCEER), Germany
| | - L Erik Daber
- Ecosystem Physiology, Albert-Ludwig-University of Freiburg, Freiburg, Germany
| | - Kathrin Kühnhammer
- Ecosystem Physiology, Albert-Ludwig-University of Freiburg, Freiburg, Germany
| | - Kinzie Bailey
- School of Natural Resources and the Environment, University of Arizona, 1064 E. Lowell St., Tucson, AZ 85721, USA
| | - Jia Hu
- School of Natural Resources and the Environment, University of Arizona, 1064 E. Lowell St., Tucson, AZ 85721, USA
| | - Jane Fudyma
- Department of Environmental Science, University of Arizona, Tucson, AZ, USA
- Department of Land, Air, and Water Resources, University of California, Davis, CA, USA
| | - Lingling Shi
- Biogeochemistry of Agroecosystems, University of Göttingen, Göttingen, Germany
- Geo-Biosphere Interactions, University of Tuebingen, Tuebingen, Germany
| | - Michaela A Dippold
- Biogeochemistry of Agroecosystems, University of Göttingen, Göttingen, Germany
- Geo-Biosphere Interactions, University of Tuebingen, Tuebingen, Germany
| | - Kathiravan Meeran
- Department of Ecology, University of Innsbruck, Sternwartestr 15, 6020 Innsbruck, Austria
| | - Luke Miller
- Biosphere 2, University of Arizona, 32540 S. Biosphere Rd, Oracle, AZ 85739, USA
| | - Michael J O'Brien
- Estación Experimental de Zonas Áridas, Consejo Superior de Investigaciones Científicas, Almería, Spain
| | - Hui Yang
- Max Planck Institute for Biogeochemistry, D-07745 Jena, Germany
| | | | - Henrik Hartmann
- Max Planck Institute for Biogeochemistry, D-07745 Jena, Germany
- Institute for Forest Protection, Julius Kühn Institute (JKI) - Federal Research Centre for Cultivated Plants, Erwin-Baur-Straße 27, D-06484 Quedlinburg, Germany
| | - Susan Trumbore
- Max Planck Institute for Biogeochemistry, D-07745 Jena, Germany
| | - Michael Bahn
- Department of Ecology, University of Innsbruck, Sternwartestr 15, 6020 Innsbruck, Austria
| | - Christiane Werner
- Ecosystem Physiology, Albert-Ludwig-University of Freiburg, Freiburg, Germany
| | - Marco M Lehmann
- Swiss Federal Research Institute WSL, 8903 Birmensdorf, Switzerland
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Hunziker S, Nazarova T, Kather M, Hartmann M, Brunner I, Schaub M, Rigling A, Hug C, Schönbeck L, Bose AK, Kammerer B, Gessler A. The metabolic fingerprint of Scots pine-root and needle metabolites show different patterns in dying trees. TREE PHYSIOLOGY 2024; 44:tpae036. [PMID: 38526975 PMCID: PMC11056600 DOI: 10.1093/treephys/tpae036] [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: 02/03/2024] [Accepted: 03/19/2024] [Indexed: 03/27/2024]
Abstract
The loss of leaves and needles in tree crowns and tree mortality are increasing worldwide, mostly as a result of more frequent and severe drought stress. Scots pine (Pinus sylvestris L.) is a tree species that is strongly affected by these developments in many regions of Europe and Asia. So far, changes in metabolic pathways and metabolite profiles in needles and roots on the trajectory toward mortality are unknown, although they could contribute to a better understanding of the mortality mechanisms. Therefore, we linked long-term observations of canopy defoliation and tree mortality with the characterization of the primary metabolite profile in needles and fine roots of Scots pines from a forest site in the Swiss Rhone valley. Our results show that Scots pines are able to maintain metabolic homeostasis in needles over a wide range of canopy defoliation levels. However, there is a metabolic tipping point at around 80-85% needle loss. Above this threshold, many stress-related metabolites (particularly osmoprotectants, defense compounds and antioxidants) increase in the needles, whereas they decrease in the fine roots. If this defoliation tipping point is exceeded, the trees are very likely to die within a few years. The different patterns between needles and roots indicate that mainly belowground carbon starvation impairs key functions for tree survival and suggest that this is an important factor explaining the increasing mortality of Scots pines.
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Affiliation(s)
- Stefan Hunziker
- Forest Dynamics, Swiss Federal Research Institute WSL, Birmensdorf 8903, Switzerland
| | - Tatiana Nazarova
- Forest Dynamics, Swiss Federal Research Institute WSL, Birmensdorf 8903, Switzerland
| | - Michel Kather
- Core Facility Metabolomics, Albert-Ludwigs-University Freiburg, Freiburg 79014, Germany
| | - Martin Hartmann
- Department of Environmental Systems Science, Institute of Agricultural Sciences, ETH Zurich, Zurich 8092, Switzerland
| | - Ivano Brunner
- Forest Soils and Biogeochemistry, Swiss Federal Research Institute WSL, Birmensdorf 8903, Switzerland
| | - Marcus Schaub
- Forest Dynamics, Swiss Federal Research Institute WSL, Birmensdorf 8903, Switzerland
| | - Andreas Rigling
- Forest Dynamics, Swiss Federal Research Institute WSL, Birmensdorf 8903, Switzerland
- Department of Environmental Systems Science, Institute of Terrestrial Ecosystems, ETH Zurich, Zurich 8092, Switzerland
| | - Christian Hug
- Forest Dynamics, Swiss Federal Research Institute WSL, Birmensdorf 8903, Switzerland
| | - Leonie Schönbeck
- Forest Dynamics, Swiss Federal Research Institute WSL, Birmensdorf 8903, Switzerland
- Department of Botany and Plant Sciences, University of California, Riverside, CA 9252, USA
| | - Arun K Bose
- Forest Dynamics, Swiss Federal Research Institute WSL, Birmensdorf 8903, Switzerland
- Forestry and Wood Technology Discipline, Khulna University, Khulna 9208, Bangladesh
| | - Bernd Kammerer
- Core Facility Metabolomics, Albert-Ludwigs-University Freiburg, Freiburg 79014, Germany
| | - Arthur Gessler
- Forest Dynamics, Swiss Federal Research Institute WSL, Birmensdorf 8903, Switzerland
- Department of Environmental Systems Science, Institute of Terrestrial Ecosystems, ETH Zurich, Zurich 8092, Switzerland
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6
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Vitali V, Schuler P, Holloway-Phillips M, D'Odorico P, Guidi C, Klesse S, Lehmann MM, Meusburger K, Schaub M, Zweifel R, Gessler A, Saurer M. Finding balance: Tree-ring isotopes differentiate between acclimation and stress-induced imbalance in a long-term irrigation experiment. GLOBAL CHANGE BIOLOGY 2024; 30:e17237. [PMID: 38488024 DOI: 10.1111/gcb.17237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 02/05/2024] [Accepted: 02/09/2024] [Indexed: 03/19/2024]
Abstract
Scots pine (Pinus sylvestris L.) is a common European tree species, and understanding its acclimation to the rapidly changing climate through physiological, biochemical or structural adjustments is vital for predicting future growth. We investigated a long-term irrigation experiment at a naturally dry forest in Switzerland, comparing Scots pine trees that have been continuously irrigated for 17 years (irrigated) with those for which irrigation was interrupted after 10 years (stop) and non-irrigated trees (control), using tree growth, xylogenesis, wood anatomy, and carbon, oxygen and hydrogen stable isotope measurements in the water, sugars and cellulose of plant tissues. The dendrochronological analyses highlighted three distinct acclimation phases to the treatments: irrigated trees experienced (i) a significant growth increase in the first 4 years of treatment, (ii) high growth rates but with a declining trend in the following 8 years and finally (iii) a regression to pre-irrigation growth rates, suggesting the development of a new growth limitation (i.e. acclimation). The introduction of the stop treatment resulted in further growth reductions to below-control levels during the third phase. Irrigated trees showed longer growth periods and lower tree-ring δ13 C values, reflecting lower stomatal restrictions than control trees. Their strong tree-ring δ18 O and δ2 H (O-H) relationship reflected the hydrological signature similarly to the control. On the contrary, the stop trees had lower growth rates, conservative wood anatomical traits, and a weak O-H relationship, indicating a physiological imbalance. Tree vitality (identified by crown transparency) significantly modulated growth, wood anatomical traits and tree-ring δ13 C, with low-vitality trees of all treatments performing similarly regardless of water availability. We thus provide quantitative indicators for assessing physiological imbalance and tree acclimation after environmental stresses. We also show that tree vitality is crucial in shaping such responses. These findings are fundamental for the early assessment of ecosystem imbalances and decline under climate change.
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Affiliation(s)
- Valentina Vitali
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Philipp Schuler
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | | | - Petra D'Odorico
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Claudia Guidi
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Stefan Klesse
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Marco M Lehmann
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Katrin Meusburger
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Marcus Schaub
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Roman Zweifel
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Arthur Gessler
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
- Institute of Terrestrial Ecosystems, ETH Zurich, Zurich, Switzerland
| | - Matthias Saurer
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
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Ouyang S, Tie L, Saurer M, Bose AK, Duan H, Li M, Xu X, Shen W, Gessler A. Divergent role of nutrient availability in determining drought responses of sessile oak and Scots pine seedlings: evidence from 13C and 15N dual labeling. TREE PHYSIOLOGY 2024; 44:tpad105. [PMID: 37672222 DOI: 10.1093/treephys/tpad105] [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: 05/16/2023] [Revised: 08/10/2023] [Accepted: 08/24/2023] [Indexed: 09/07/2023]
Abstract
Increased soil nutrient availability can promote tree growth while drought impairs metabolic functioning and induces tree mortality. However, limited information is available about the role of nutrients in the drought responses of trees. A greenhouse experiment was conducted with sessile oak (Quercus petraea (Matt.) Liebl) and Scots pine (Pinus sylvestris L.) seedlings, which were subjected to three fertilization treatments in the first year and two water regimes in the second year. Old and newly fixed carbon (C) and nitrogen (N) allocation were traced by dual labeling with 13C and 15N tracers, respectively, at two time points. Leaf gas exchange, biomass, as well as N and nonstructural carbohydrate (NSC) concentrations of all organs were measured. Fertilization predisposed sessile oak to drought-induced mortality, mainly by prioritizing aboveground growth, C and N allocation, reducing root NSC concentrations and decreasing old C contribution to new growth of leaves. In contrast, fertilization did not additionally predispose Scots pine to drought, with minor effects of fertilization and drought on newly fixed and old C allocation, tissues N and NSC concentrations. The role of nutrients for drought responses of trees seems to be species-specific. Therefore, we suggest nutrient availability and species identity to be considered in the framework of physiological mechanisms affecting drought-induced mortality.
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Affiliation(s)
- Shengnan Ouyang
- Institute for Forest Resources and Environment of Guizhou, Key Laboratory of Forest Cultivation in Plateau Mountain of Guizhou Province, College of Forestry, Guizhou University, Guiyang 550025, China
- Swiss Federal Institute for Forest, Snow and Landscape Research, Forest Dynamics, Birmensdorf 8903, Switzerland
| | - Liehua Tie
- Institute for Forest Resources and Environment of Guizhou, Key Laboratory of Forest Cultivation in Plateau Mountain of Guizhou Province, College of Forestry, Guizhou University, Guiyang 550025, China
| | - Matthias Saurer
- Swiss Federal Institute for Forest, Snow and Landscape Research, Forest Dynamics, Birmensdorf 8903, Switzerland
| | - Arun K Bose
- Swiss Federal Institute for Forest, Snow and Landscape Research, Forest Dynamics, Birmensdorf 8903, Switzerland
- Forestry and Wood Technology Discipline, Khulna University, Khulna 9208, Bangladesh
| | - Honglang Duan
- Institute for Forest Resources and Environment of Guizhou, Key Laboratory of Forest Cultivation in Plateau Mountain of Guizhou Province, College of Forestry, Guizhou University, Guiyang 550025, China
| | - Maihe Li
- Swiss Federal Institute for Forest, Snow and Landscape Research, Forest Dynamics, Birmensdorf 8903, Switzerland
- Key Laboratory of Geographical Processes and Ecological Security in Changbai Mountains, Ministry of Education, School of Geographical Sciences, Northeast Normal University, Changchun 130024, China
- School of Life Science, Hebei University, Baoding 071000, China
| | - Xingliang Xu
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Weijun Shen
- Guangxi Key Laboratory of Forest Ecology and Conservation, State Key Laboratory for Conservation and Utilization of Agro-Bioresources, College of Forestry, Guangxi University, Nanning, Guangxi 530004, China
| | - Arthur Gessler
- Swiss Federal Institute for Forest, Snow and Landscape Research, Forest Dynamics, Birmensdorf 8903, Switzerland
- Institute of Terrestrial Ecosystems, ETH Zurich, Zurich 8902, Switzerland
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8
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Salomón RL, Helm J, Gessler A, Grams TEE, Hilman B, Muhr J, Steppe K, Wittmann C, Hartmann H. The quandary of sources and sinks of CO2 efflux in tree stems-new insights and future directions. TREE PHYSIOLOGY 2024; 44:tpad157. [PMID: 38214910 DOI: 10.1093/treephys/tpad157] [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: 09/15/2023] [Accepted: 12/12/2023] [Indexed: 01/13/2024]
Abstract
Stem respiration (RS) substantially contributes to the return of photo assimilated carbon to the atmosphere and, thus, to the tree and ecosystem carbon balance. Stem CO2 efflux (ECO2) is often used as a proxy for RS. However, this metric has often been challenged because of the uncertain origin of CO2 emitted from the stem due to post-respiratory processes. In this Insight, we (i) describe processes affecting the quantification of RS, (ii) review common methodological approaches to quantify and model RS and (iii) develop a research agenda to fill the most relevant knowledge gaps that we identified. Dissolution, transport and accumulation of respired CO2 away from its production site, reassimilation of respired CO2 via stem photosynthesis and the enzyme phosphoenolpyruvate carboxylase, axial CO2 diffusion in the gas phase, shifts in the respiratory substrate and non-respiratory oxygen (O2) consumption are the most relevant processes causing divergence between RS and measured stem gas exchange (ECO2 or O2 influx, IO2). Two common methodological approaches to estimate RS, namely the CO2 mass balance approach and the O2 consumption technique, circumvent some of these processes but have yielded inconsistent results regarding the fate of respired CO2. Stem respiration modelling has recently progressed at the organ and tree levels. However, its implementation in large-scale models, commonly operated from a source-driven perspective, is unlikely to reflect adequate mechanisms. Finally, we propose hypotheses and approaches to advance the knowledge of the stem carbon balance, the role of sap pH on RS, the reassimilation of respired CO2, RS upscaling procedures, large-scale RS modelling and shifts in respiratory metabolism during environmental stress.
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Affiliation(s)
- Roberto L Salomón
- Universidad Politécnica de Madrid (UPM), Departamento de Sistemas y Recursos Naturales, Research Group FORESCENT, Antonio Novais 10, 28040, Madrid, Spain
- Department of Plants and Crops, Laboratory of Plant Ecology, Ghent University, Faculty of Bioscience Engineering, Coupure Links 653, 9000 Ghent, Belgium
| | - Juliane Helm
- Max-Planck-Institute for Biogeochemistry, Biogeochemical Processes, Hans-Knöll-Str. 10, 07743 Jena, Germany
- Department of Environmental Sciences - Botany, Basel University, Schönbeinstr. 6, Basel CH-4056, Switzerland
| | - Arthur Gessler
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zurcherstrasse 111, 8903 Birmensdorf, Switzerland
- Institute of Terrestrial Ecosystems, ETH Zürich, Rämistrasse 101, 8902 Zurich, Switzerland
| | - Thorsten E E Grams
- Technical University of Munich, Ecophysiology of Plants, Land Surface - Atmosphere Interactions, Von-Carlowitz-Platz 2, 85354 Freising, Germany
| | - Boaz Hilman
- Max-Planck-Institute for Biogeochemistry, Biogeochemical Processes, Hans-Knöll-Str. 10, 07743 Jena, Germany
| | - Jan Muhr
- Department of Forest Botany and Tree Physiology, Laboratory for Radioisotopes, Georg-August Universität Göttingen, Büsgenweg 2, 37077 Göttingen, Germany
| | - Kathy Steppe
- Department of Plants and Crops, Laboratory of Plant Ecology, Ghent University, Faculty of Bioscience Engineering, Coupure Links 653, 9000 Ghent, Belgium
| | - Christiane Wittmann
- Faculty of Biology, Botanical Garden, University of Duisburg-Essen, Universitätsstrasse 5, 45117 Essen, Germany
| | - Henrik Hartmann
- Max-Planck-Institute for Biogeochemistry, Biogeochemical Processes, Hans-Knöll-Str. 10, 07743 Jena, Germany
- Institute for Forest Protection, Julius Kühn Institute Federal Research Centre for Cultivated Plants, Erwin-Baur-Straße 27, 06484 Quedlinburg, Germany
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Rog I, Hilman B, Fox H, Yalin D, Qubaja R, Klein T. Increased belowground tree carbon allocation in a mature mixed forest in a dry versus a wet year. GLOBAL CHANGE BIOLOGY 2024; 30:e17172. [PMID: 38343030 DOI: 10.1111/gcb.17172] [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: 08/05/2023] [Revised: 01/07/2024] [Accepted: 01/08/2024] [Indexed: 02/15/2024]
Abstract
Tree species differ in their carbon (C) allocation strategies during environmental change. Disentangling species-specific strategies and contribution to the C balance of mixed forests requires observations at the individual tree level. We measured a complete set of C pools and fluxes at the tree level in five tree species, conifers and broadleaves, co-existing in a mature evergreen mixed Mediterranean forest. Our study period included a drought year followed by an above-average wet year, offering an opportunity to test the effect of water availability on tree C allocation. We found that in comparison to the wet year, C uptake was lower in the dry year, C use was the same, and allocation to belowground sinks was higher. Among the five major C sinks, respiration was the largest (ca. 60%), while root exudation (ca. 10%) and reproduction (ca. 2%) were those that increased the most in the dry year. Most trees relied on stored starch for maintaining a stable soluble sugars balance, but no significant differences were detected in aboveground storage between dry and wet years. The detailed tree-level analysis of nonstructural carbohydrates and δ13 C dynamics suggest interspecific differences in C allocation among fluxes and tissues, specifically in response to the varying water availability. Overall, our findings shed light on mixed forest physiological responses to drought, an increasing phenomenon under the ongoing climate change.
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Affiliation(s)
- Ido Rog
- Department of Plant & Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Boaz Hilman
- Department of Biogeochemical Processes, Max-Planck Institute for Biogeochemistry, Jena, Germany
- The Institute of Earth Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Hagar Fox
- Department of Plant & Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - David Yalin
- Department of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Rafat Qubaja
- Department of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Tamir Klein
- Department of Plant & Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
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10
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Jaeger FC, Handa IT, Paquette A, Parker WC, Messier C. Young temperate tree species show different fine root acclimation capacity to growing season water availability. PLANT AND SOIL 2023; 496:485-504. [PMID: 38510944 PMCID: PMC10948563 DOI: 10.1007/s11104-023-06377-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Accepted: 10/30/2023] [Indexed: 03/22/2024]
Abstract
Background and aims Changes in water availability during the growing season are becoming more frequent due to climate change. Our study aimed to compare the fine-root acclimation capacity (plasticity) of six temperate tree species aged six years and exposed to high or low growing season soil water availability over five years. Methods Root samples were collected from the five upper strata of mineral soil to a total soil depth of 30 cm in monoculture plots of Acer saccharum Marsh., Betula papyrifera Marsh., Larix laricina K. Koch, Pinus strobus L., Picea glauca (Moench) Voss and Quercus rubra L. established at the International Diversity Experiment Network with Trees (IDENT) field experiment in Sault Ste. Marie, Ontario, Canada. Four replicates of each monoculture were subjected to high or low water availability treatments. Results Absorptive fine root density increased by 67% for Larix laricina, and 90% for Picea glauca, under the high-water availability treatment at 0-5 cm soil depth. The two late successional, slower growing tree species, Acer saccharum and Picea glauca, showed higher plasticity in absorptive fine root biomass in the upper 5 cm of soil (PIv = 0.36 & 0.54 respectively), and lower plasticity in fine root depth over the entire 30 cm soil profile compared to the early successional, faster growing tree species Betula papyrifera and Larix laricina. Conclusion Temperate tree species show contrasting acclimation responses in absorptive fine root biomass and rooting depth to differences in water availability. Some of these responses vary with tree species successional status and seem to benefit both early and late successional tree species. Supplementary Information The online version contains supplementary material available at 10.1007/s11104-023-06377-w.
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Affiliation(s)
- Florentin C. Jaeger
- Centre for Forest Research, Département des Sciences Biologiques, Université du Québec à Montréal, Montréal, QC Canada
| | - I. Tanya Handa
- Centre for Forest Research, Département des Sciences Biologiques, Université du Québec à Montréal, Montréal, QC Canada
| | - Alain Paquette
- Centre for Forest Research, Département des Sciences Biologiques, Université du Québec à Montréal, Montréal, QC Canada
| | - William C. Parker
- Forest Research and Monitoring Section, Ontario Ministry of Natural Resources and Forestry, Sault Ste. Marie, ON Canada
| | - Christian Messier
- Centre for Forest Research, Département des Sciences Biologiques, Université du Québec à Montréal, Montréal, QC Canada
- Institut des Sciences de La Forêt tempérée, Université du Québec en Outaouais, Ripon, Canada
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11
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Liu Z, Ye L, Jiang J, Liu R, Xu Y, Jia G. Increased uptake of deep soil water promotes drought resistance in mixed forests. PLANT, CELL & ENVIRONMENT 2023; 46:3218-3228. [PMID: 37287350 DOI: 10.1111/pce.14642] [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: 02/01/2023] [Revised: 05/19/2023] [Accepted: 05/30/2023] [Indexed: 06/09/2023]
Abstract
The intensity and frequency of droughts are projected to rise in recent years and adversely affect forests. Thus, information on plant water use and acclimation during and after droughts is crucial. This study used the stable isotope and thermal dissipation probes to detect the water-use adaptation of mixed forests to drought using a precipitation gradient control experiment in the field. The results showed that Platycladus orientalis and Quercus variabilis mainly absorbed stable water from deep soil layers during the drought (32.05% and 28.2%, respectively). The synergetic nocturnal sap flow in both species replenished the water loss, but P. orientalis experienced a greater decline in transpiration acclimation to drought. The transpiration of Q. variabilis remained high since it was mainly induced by radiation. After short-term exposure to drought, P. orientalis majorly obtained shallow soil water, confirming its sensitivity to shallow water. Contrarily, Q. variabilis mainly absorbed stable water from deep soil layers regardless of the soil water content. Therefore, these findings suggest that Q. variabilis cannot physiologically adjust to extreme drought events, possibly limiting their future distributions and altering the composition of boreal forests.
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Affiliation(s)
- Ziqiang Liu
- Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, China
- Center of Ecological Forestry Development of Jingning She Nationality Autonomous County, Lishui, China
| | - Limin Ye
- Center of Ecological Forestry Development of Jingning She Nationality Autonomous County, Lishui, China
| | - Jiang Jiang
- Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, China
| | - Rilin Liu
- Center of Ecological Forestry Development of Jingning She Nationality Autonomous County, Lishui, China
| | - Yuanke Xu
- Center of Ecological Forestry Development of Jingning She Nationality Autonomous County, Lishui, China
| | - Guodong Jia
- Key Laboratory of Soil and Water Conservation and Desertification Combating of Ministry of Education, Beijing Forestry University, Beijing, China
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12
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Solly EF, Jaeger ACH, Barthel M, Werner RA, Zürcher A, Hagedorn F, Six J, Hartmann M. Water limitation intensity shifts carbon allocation dynamics in Scots pine mesocosms. PLANT AND SOIL 2023; 490:499-519. [PMID: 37780069 PMCID: PMC10533586 DOI: 10.1007/s11104-023-06093-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Accepted: 05/23/2023] [Indexed: 10/03/2023]
Abstract
Background and aims Tree species worldwide suffer from extended periods of water limitation. These conditions not only affect the growth and vitality of trees but also feed back on the cycling of carbon (C) at the plant-soil interface. However, the impact of progressing water loss from soils on the transfer of assimilated C belowground remains unresolved. Methods Using mesocosms, we assessed how increasing levels of water deficit affect the growth of Pinus sylvestris saplings and performed a 13C-CO2 pulse labelling experiment to trace the pathway of assimilated C into needles, fine roots, soil pore CO2, and phospholipid fatty acids of soil microbial groups. Results With increasing water limitation, trees partitioned more biomass belowground at the expense of aboveground growth. Moderate levels of water limitation barely affected the uptake of 13C label and the transit time of C from needles to the soil pore CO2. Comparatively, more severe water limitation increased the fraction of 13C label that trees allocated to fine roots and soil fungi while a lower fraction of 13CO2 was readily respired from the soil. Conclusions When soil water becomes largely unavailable, C cycling within trees becomes slower, and a fraction of C allocated belowground may accumulate in fine roots or be transferred to the soil and associated microorganisms without being metabolically used. Supplementary Information The online version contains supplementary material available at 10.1007/s11104-023-06093-5.
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Affiliation(s)
- Emily F. Solly
- Department of Environmental Systems Science, Sustainable Agroecosystems Group, ETH Zürich, Universitätstrasse 2, 8092 Zurich, Switzerland
| | - Astrid C. H. Jaeger
- Department of Environmental Systems Science, Sustainable Agroecosystems Group, ETH Zürich, Universitätstrasse 2, 8092 Zurich, Switzerland
| | - Matti Barthel
- Department of Environmental Systems Science, Sustainable Agroecosystems Group, ETH Zürich, Universitätstrasse 2, 8092 Zurich, Switzerland
| | - Roland A. Werner
- Department of Environmental Systems Science, Grassland Sciences Group, ETH Zurich, Universitätstrasse 2, 8092 Zurich, Switzerland
| | - Alois Zürcher
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Biogeochemistry Group, Zürcherstrasse 111, Birmensdorf, 8903 Switzerland
| | - Frank Hagedorn
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Biogeochemistry Group, Zürcherstrasse 111, Birmensdorf, 8903 Switzerland
| | - Johan Six
- Department of Environmental Systems Science, Sustainable Agroecosystems Group, ETH Zürich, Universitätstrasse 2, 8092 Zurich, Switzerland
| | - Martin Hartmann
- Department of Environmental Systems Science, Sustainable Agroecosystems Group, ETH Zürich, Universitätstrasse 2, 8092 Zurich, Switzerland
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13
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Zhang K, Qiu Y, Zhao Y, Wang S, Deng J, Chen M, Xu X, Wang H, Bai T, He T, Zhang Y, Chen H, Wang Y, Hu S. Moderate precipitation reduction enhances nitrogen cycling and soil nitrous oxide emissions in a semi-arid grassland. GLOBAL CHANGE BIOLOGY 2023; 29:3114-3129. [PMID: 36892227 DOI: 10.1111/gcb.16672] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 02/28/2023] [Accepted: 03/01/2023] [Indexed: 05/03/2023]
Abstract
The ongoing climate change is predicted to induce more weather extremes such as frequent drought and high-intensity precipitation events, causing more severe drying-rewetting cycles in soil. However, it remains largely unknown how these changes will affect soil nitrogen (N)-cycling microbes and the emissions of potent greenhouse gas nitrous oxide (N2 O). Utilizing a field precipitation manipulation in a semi-arid grassland on the Loess Plateau, we examined how precipitation reduction (ca. -30%) influenced soil N2 O and carbon dioxide (CO2 ) emissions in field, and in a complementary lab-incubation with simulated drying-rewetting cycles. Results obtained showed that precipitation reduction stimulated plant root turnover and N-cycling processes, enhancing soil N2 O and CO2 emissions in field, particularly after each rainfall event. Also, high-resolution isotopic analyses revealed that field soil N2 O emissions primarily originated from nitrification process. The incubation experiment further showed that in field soils under precipitation reduction, drying-rewetting stimulated N mineralization and ammonia-oxidizing bacteria in favor of genera Nitrosospira and Nitrosovibrio, increasing nitrification and N2 O emissions. These findings suggest that moderate precipitation reduction, accompanied with changes in drying-rewetting cycles under future precipitation scenarios, may enhance N cycling processes and soil N2 O emissions in semi-arid ecosystems, feeding positively back to the ongoing climate change.
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Affiliation(s)
- Kangcheng Zhang
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yunpeng Qiu
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yunfeng Zhao
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, China
| | - Shuhong Wang
- Ningxia Yunwu Mountains Grassland Natural Reserve Administration, Guyuan, 756000, China
| | - Jun Deng
- Ningxia Yunwu Mountains Grassland Natural Reserve Administration, Guyuan, 756000, China
| | - Mengfei Chen
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, China
| | - Xinyu Xu
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, China
| | - Hao Wang
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, China
| | - Tongshuo Bai
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, China
| | - Tangqing He
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yi Zhang
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, China
| | - Huaihai Chen
- School of Ecology, Sun Yat-Sen University, Guangzhou, 510006, China
| | - Yi Wang
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, China
| | - Shuijin Hu
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, North Carolina, 27695, USA
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14
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Saurer M, Sahlstedt E, Rinne-Garmston KT, Lehmann MM, Oettli M, Gessler A, Treydte K. Progress in high-resolution isotope-ratio analysis of tree rings using laser ablation. TREE PHYSIOLOGY 2023; 43:694-705. [PMID: 36519757 DOI: 10.1093/treephys/tpac141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 11/29/2022] [Accepted: 12/11/2022] [Indexed: 05/13/2023]
Abstract
Stable isotope ratio analysis of tree rings has been widely and successfully applied in recent decades for climatic and environmental reconstructions. These studies were mostly conducted at an annual resolution, considering one measurement per tree ring, often focusing on latewood. However, much more information could be retrieved with high-resolution intra-annual isotope studies, based on the fact that the wood cells and the corresponding organic matter are continuously laid down during the growing season. Such studies are still relatively rare, but have a unique potential for reconstructing seasonal climate variations or short-term changes in physiological plant properties, like water-use efficiency. The reason for this research gap is mostly technical, as on the one hand sub-annual, manual splitting of rings is very tedious, while on the other hand automated laser ablation for high-resolution analyses is not yet well established and available. Here, we give an update on the current status of laser ablation research for analysis of the carbon isotope ratio (δ13C) of wood, describe an easy-to-use laser ablation system, its operation and discuss practical issues related to tree core preparation, including cellulose extraction. The results show that routine analysis with up to 100 laser shot-derived δ13C-values daily and good precision and accuracy (ca. 0.1‰) comparable to conventional combustion in an elemental analyzer are possible. Measurements on resin-extracted wood is recommended as most efficient, but laser ablation is also possible on cellulose extracted wood pieces. Considering the straightforward sample preparation, the technique is therefore ripe for wide-spread application. With this work, we hope to stimulate future progress in the promising field of high-resolution environmental reconstruction using laser ablation.
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Affiliation(s)
- Matthias Saurer
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zürcherstrasse 111, Birmensdorf 8903, Switzerland
| | - Elina Sahlstedt
- Natural Resources Institute Finland (Luke), Latokartanonkaari 9, Helsinki 00790, Finland
| | - Katja T Rinne-Garmston
- Natural Resources Institute Finland (Luke), Latokartanonkaari 9, Helsinki 00790, Finland
| | - Marco M Lehmann
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zürcherstrasse 111, Birmensdorf 8903, Switzerland
| | - Manuela Oettli
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zürcherstrasse 111, Birmensdorf 8903, Switzerland
| | - Arthur Gessler
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zürcherstrasse 111, Birmensdorf 8903, Switzerland
- Institute of Terrestrial Ecosystems, ETH Zurich, Universitaetstrasse 16, Zurich 8092, Switzerland
| | - Kerstin Treydte
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zürcherstrasse 111, Birmensdorf 8903, Switzerland
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15
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Zhang YL, Yang Y, Saurer M, Schaub M, Gessler A, Lehmann MM, Rigling A, Walser M, Stierli B, Hajjar N, Christen D, Li MH. Sugar infusion into trees: A novel method to study tree carbon relations and its regulations. FRONTIERS IN PLANT SCIENCE 2023; 14:1142595. [PMID: 36909442 PMCID: PMC9996627 DOI: 10.3389/fpls.2023.1142595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Accepted: 02/14/2023] [Indexed: 06/18/2023]
Abstract
Many carbon-related physiological questions in plants such as carbon (C) limitation or starvation have not yet been resolved thoroughly due to the lack of suitable experimental methodology. As a first step towards resolving these problems, we conducted infusion experiments with bonsai trees (Ficus microcarpa) and young maple trees (Acer pseudoplatanus) in greenhouse, and with adult Scots pine trees (Pinus sylvestris) in the field, that were "fed" with 13C-labelled glucose either through the phloem or the xylem. We then traced the 13C-signal in plant organic matter and respiration to test whether trees can take up and metabolize exogenous sugars infused. Ten weeks after infusion started, xylem but not phloem infusion significantly increased the δ13C values in both aboveground and belowground tissues of the bonsai trees in the greenhouse, whereas xylem infusion significantly increased xylem δ13C values and phloem infusion significantly increased phloem δ13C values of the adult pines in the field experiment, compared to the corresponding controls. The respiration measurement experiment with young maple trees showed significantly increased δ13C-values in shoot respired CO2 at the time of four weeks after xylem infusion started. Our results clearly indicate that trees do translocate and metabolize exogenous sugars infused, and because the phloem layer is too thin, and thus xylem infusion can be better operated than phloem infusion. This tree infusion method developed here opens up new avenues and has great potential to be used for research on the whole plant C balance and its regulation in response to environmental factors and extreme stress conditions.
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Affiliation(s)
- Yan-Li Zhang
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
- Department of Environmental Systems Science, Institute of Terrestrial Ecosystems, ETH Zürich, Zürich, Switzerland
| | - Yue Yang
- College of Ecology and Environment, Hainan University, Haikou, China
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Matthias Saurer
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Marcus Schaub
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Arthur Gessler
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
- Department of Environmental Systems Science, Institute of Terrestrial Ecosystems, ETH Zürich, Zürich, Switzerland
| | - Marco M. Lehmann
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Andreas Rigling
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
- Department of Environmental Systems Science, Institute of Terrestrial Ecosystems, ETH Zürich, Zürich, Switzerland
| | - Marco Walser
- Forest Soils and Biogeochemistry, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Beat Stierli
- Forest Soils and Biogeochemistry, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Noureddine Hajjar
- Forest Soils and Biogeochemistry, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Daniel Christen
- Forest Soils and Biogeochemistry, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Mai-He Li
- College of Ecology and Environment, Hainan University, Haikou, China
- Key Laboratory of Geographical Processes and Ecological Security in Changbai Mountains, Ministry of Education, School of Geographical Sciences, Northeast Normal University, Changchun, Jilin, China
- College of Life Science, Hebei University, Baoding, Hebei, China
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16
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Tang Y, Schiestl-Aalto P, Saurer M, Sahlstedt E, Kulmala L, Kolari P, Ryhti K, Salmon Y, Jyske T, Ding Y, Bäck J, Rinne-Garmston KT. Tree organ growth and carbon allocation dynamics impact the magnitude and δ13C signal of stem and soil CO2 fluxes. TREE PHYSIOLOGY 2022; 42:2404-2418. [PMID: 35849053 PMCID: PMC10101690 DOI: 10.1093/treephys/tpac079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 06/08/2022] [Accepted: 07/02/2022] [Indexed: 05/14/2023]
Abstract
Incomplete knowledge of carbon (C) allocation dynamics in trees hinders accurate modeling and future predictions of tree growth. We studied C allocation dynamics in a mature Pinus sylvestris L. dominated forest with a novel analytical approach, allowing the first comparison of: (i) magnitude and δ13C of shoot, stem and soil CO2 fluxes (Ashoot, Rstem and Rsoil), (ii) concentration and δ13C of compound-specific and/or bulk non-structural carbohydrates (NSCs) in phloem and roots and (iii) growth of stem and fine roots. Results showed a significant effect of phloem NSC concentrations on tracheid growth, and both variables significantly impacted Rstem. Also, concentrations of root NSCs, especially starch, had a significant effect on fine root growth, although no effect of root NSC concentrations or root growth was detected on Rsoil. Time series analysis between δ13C of Ashoot and δ13C of Rstem or δ13C of Rsoil revealed strengthened C allocation to stem or roots under high C demands. Furthermore, we detected a significant correlation between δ13C of Rstem and δ13C of phloem sucrose and glucose, but not for starch or water-soluble carbohydrates. Our results indicate the need to include C allocation dynamics into tree growth models. We recommend using compound-specific concentration and δ13C analysis to reveal C allocation processes that may not be detected by the conventional approach that utilizes bulk organic matter.
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Affiliation(s)
| | - Pauliina Schiestl-Aalto
- Institute for Atmospheric and Earth System Research
(INAR)/Physics, Faculty of Science, University of
Helsinki, P.O. Box 68, FI-00014 Helsinki, Finland
| | - Matthias Saurer
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape
Research WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
| | - Elina Sahlstedt
- Bioeconomy and Environment Unit, Natural Resources Institute
Finland, Latokartanonkaari 9, FI-00790 Helsinki, Finland
| | - Liisa Kulmala
- Institute for Atmospheric and Earth System Research (INAR)/Forest
Sciences, Faculty of Agriculture and Forestry, University
of Helsinki, P.O. Box 27, FI-00014 Helsinki, Finland
- Finnish Meteorological Institute, P.O. Box 503, FI-00101
Helsinki, Finland
| | - Pasi Kolari
- Institute for Atmospheric and Earth System Research
(INAR)/Physics, Faculty of Science, University of
Helsinki, P.O. Box 68, FI-00014 Helsinki, Finland
| | - Kira Ryhti
- Institute for Atmospheric and Earth System Research (INAR)/Forest
Sciences, Faculty of Agriculture and Forestry, University
of Helsinki, P.O. Box 27, FI-00014 Helsinki, Finland
| | - Yann Salmon
- Institute for Atmospheric and Earth System Research (INAR)/Forest
Sciences, Faculty of Agriculture and Forestry, University
of Helsinki, P.O. Box 27, FI-00014 Helsinki, Finland
- Institute for Atmospheric and Earth System Research
(INAR)/Physics, Faculty of Science, University of
Helsinki, P.O. Box 68, FI-00014 Helsinki, Finland
| | - Tuula Jyske
- Production Systems Unit, Natural Resources Institute Finland,
Tietotie 2, FI-02150 Espoo, Finland
| | - Yiyang Ding
- Department of Forest Sciences, Faculty of Agriculture and
Forestry, University of Helsinki, P.O. Box 27, FI-00014
Helsinki, Finland
| | - Jaana Bäck
- Institute for Atmospheric and Earth System Research (INAR)/Forest
Sciences, Faculty of Agriculture and Forestry, University
of Helsinki, P.O. Box 27, FI-00014 Helsinki, Finland
| | - Katja T Rinne-Garmston
- Bioeconomy and Environment Unit, Natural Resources Institute
Finland, Latokartanonkaari 9, FI-00790 Helsinki, Finland
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17
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Steidinger BS, Büntgen U, Stobbe U, Tegel W, Sproll L, Haeni M, Moser B, Bagi I, Bonet J, Buée M, Dauphin B, Martínez‐Peña F, Molinier V, Zweifel R, Egli S, Peter M. The fall of the summer truffle: Recurring hot, dry summers result in declining fruitbody production of Tuber aestivum in Central Europe. GLOBAL CHANGE BIOLOGY 2022; 28:7376-7390. [PMID: 36200354 PMCID: PMC9828532 DOI: 10.1111/gcb.16424] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Accepted: 08/14/2022] [Indexed: 06/16/2023]
Abstract
Global warming is pushing populations outside their range of physiological tolerance. According to the environmental envelope framework, the most vulnerable populations occur near the climatic edge of their species' distributions. In contrast, populations from the climatic center of the species range should be relatively buffered against climate warming. We tested this latter prediction using a combination of linear mixed effects and machine learning algorithms on an extensive, citizen-scientist generated dataset on the fruitbody productivity of the Burgundy (aka summer) truffle (Tuber aestivum Vittad.), a keystone, ectomycorrhizal tree-symbiont occurring on a wide range of temperate climates. T. aestivum's fruitbody productivity was monitored at 3-week resolution over up to 8 continuous years at 20 sites distributed in the climatic center of its European distribution in southwest Germany and Switzerland. We found that T. aestivum fruitbody production is more sensitive to summer drought than would be expected from the breadth of its species' climatic niche. The monitored populations occurring nearly 5°C colder than the edge of their species' climatic distribution. However, interannual fruitbody productivity (truffle mass year-1 ) fell by a median loss of 22% for every 1°C increase in summer temperature over a site's 30-year mean. Among the most productive monitored populations, the temperature sensitivity was even higher, with single summer temperature anomalies of 3°C sufficient to stop fruitbody production altogether. Interannual truffle productivity was also related to the phenology of host trees, with ~22 g less truffle mass for each 1-day reduction in the length of the tree growing season. Increasing summer drought extremes are therefore likely to reduce fruiting among summer truffle populations throughout Central Europe. Our results suggest that European T. aestivum may be a mosaic of vulnerable populations, sensitive to climate-driven declines at lower thresholds than implied by its species distribution model.
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Affiliation(s)
- Brian S. Steidinger
- Department of EcologyUniversity of KonstanzKonstanzGermany
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
| | - Ulf Büntgen
- Global Change Research Centre (Czech Globe)BrnoCzech Republic
- Department of GeographyUniversity of CambridgeCambridgeUK
- Department of Geography, Faculty of ScienceMasaryk UniversityBrnoCzech Republic
| | | | - Willy Tegel
- Forest GrowthAlbert‐Ludwigs UniversityFreiburgGermany
| | | | - Matthias Haeni
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
| | - Barbara Moser
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
| | | | | | - Marc Buée
- Laboratory of Excellence ARBRE, INRAE‐Grand Est, Interactions Arbres/MicroorganismesINRAE, UMR 1136 INRAE‐University of LorraineChampenouxFrance
| | - Benjamin Dauphin
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
| | - Fernando Martínez‐Peña
- Agrifood Research and Technology Centre of Aragon CITAZaragozaSpain
- European Mycological Institute EGTC‐EMISoriaSpain
| | - Virginie Molinier
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
| | - Roman Zweifel
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
| | - Simon Egli
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
| | - Martina Peter
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
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18
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Hikino K, Danzberger J, Riedel VP, Hesse BD, Hafner BD, Gebhardt T, Rehschuh R, Ruehr NK, Brunn M, Bauerle TL, Landhäusser SM, Lehmann MM, Rötzer T, Pretzsch H, Buegger F, Weikl F, Pritsch K, Grams TEE. Dynamics of initial carbon allocation after drought release in mature Norway spruce-Increased belowground allocation of current photoassimilates covers only half of the carbon used for fine-root growth. GLOBAL CHANGE BIOLOGY 2022; 28:6889-6905. [PMID: 36039835 DOI: 10.1111/gcb.16388] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Accepted: 07/02/2022] [Indexed: 06/15/2023]
Abstract
After drought events, tree recovery depends on sufficient carbon (C) allocation to the sink organs. The present study aimed to elucidate dynamics of tree-level C sink activity and allocation of recent photoassimilates (Cnew ) and stored C in c. 70-year-old Norway spruce (Picea abies) trees during a 4-week period after drought release. We conducted a continuous, whole-tree 13 C labeling in parallel with controlled watering after 5 years of experimental summer drought. The fate of Cnew to growth and CO2 efflux was tracked along branches, stems, coarse- and fine roots, ectomycorrhizae and root exudates to soil CO2 efflux after drought release. Compared with control trees, drought recovering trees showed an overall 6% lower C sink activity and 19% less allocation of Cnew to aboveground sinks, indicating a low priority for aboveground sinks during recovery. In contrast, fine-root growth in recovering trees was seven times greater than that of controls. However, only half of the C used for new fine-root growth was comprised of Cnew while the other half was supplied by stored C. For drought recovery of mature spruce trees, in addition to Cnew , stored C appears to be critical for the regeneration of the fine-root system and the associated water uptake capacity.
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Affiliation(s)
- Kyohsuke Hikino
- Professorship for Land Surface-Atmosphere Interactions, Ecophysiology of Plants, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Jasmin Danzberger
- Institute of Biochemical Plant Pathology, Helmholtz Zentrum München - German Research Center for Environmental Health (GmbH), Neuherberg, Germany
| | - Vincent P Riedel
- Professorship for Land Surface-Atmosphere Interactions, Ecophysiology of Plants, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Benjamin D Hesse
- Professorship for Land Surface-Atmosphere Interactions, Ecophysiology of Plants, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Benjamin D Hafner
- School of Integrative Plant Science, Cornell University, Ithaca, New York, USA
| | - Timo Gebhardt
- Professorship for Land Surface-Atmosphere Interactions, Ecophysiology of Plants, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Romy Rehschuh
- Karlsruhe Institute of Technology, Institute of Meteorology and Climate Research-Atmospheric Environmental Research (KIT/IMK-IFU), Garmisch-Partenkirchen, Germany
- Institute of General Ecology and Environmental Protection, Technische Universität Dresden, Pienner Str. 7, Tharandt, 01737, Germany
| | - Nadine K Ruehr
- Karlsruhe Institute of Technology, Institute of Meteorology and Climate Research-Atmospheric Environmental Research (KIT/IMK-IFU), Garmisch-Partenkirchen, Germany
| | - Melanie Brunn
- Institute for Environmental Sciences, University Koblenz-Landau, Landau, Germany
| | - Taryn L Bauerle
- School of Integrative Plant Science, Cornell University, Ithaca, New York, USA
| | - Simon M Landhäusser
- Department of Renewable Resources, University of Alberta, Edmonton, Alberta, Canada
| | - Marco M Lehmann
- Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Forest Dynamics, Birmensdorf, Switzerland
| | - Thomas Rötzer
- Forest Growth and Yield Science, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Hans Pretzsch
- Forest Growth and Yield Science, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Franz Buegger
- Institute of Biochemical Plant Pathology, Helmholtz Zentrum München - German Research Center for Environmental Health (GmbH), Neuherberg, Germany
| | - Fabian Weikl
- Professorship for Land Surface-Atmosphere Interactions, Ecophysiology of Plants, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
- Institute of Biochemical Plant Pathology, Helmholtz Zentrum München - German Research Center for Environmental Health (GmbH), Neuherberg, Germany
| | - Karin Pritsch
- Institute of Biochemical Plant Pathology, Helmholtz Zentrum München - German Research Center for Environmental Health (GmbH), Neuherberg, Germany
| | - Thorsten E E Grams
- Professorship for Land Surface-Atmosphere Interactions, Ecophysiology of Plants, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
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19
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Cong Y, Saurer M, Bai E, Siegwolf R, Gessler A, Liu K, Han H, Dang Y, Xu W, He HS, Li MH. In situ 13CO2 labeling reveals that alpine treeline trees allocate less photoassimilates to roots compared with low-elevation trees. TREE PHYSIOLOGY 2022; 42:1943-1956. [PMID: 35535565 DOI: 10.1093/treephys/tpac048] [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: 10/18/2021] [Accepted: 04/13/2022] [Indexed: 06/14/2023]
Abstract
Carbon (C) allocation plays a crucial role for survival and growth of alpine treeline trees, however it is still poorly understood. Using in situ 13CO2 labeling, we investigated the leaf photosynthesis and the allocation of 13C labeled photoassimilates in various tissues (leaves, twigs and fine roots) in treeline trees and low-elevation trees. Non-structural carbohydrate concentrations were also determined. The alpine treeline trees (2000 m. a.s.l.), compared with low-elevation trees (1700 m a.s.l.), did not show any disadvantage in photosynthesis, but the former allocated proportionally less newly assimilated C belowground than the latter. Carbon residence time in leaves was longer in treeline trees (19 days) than that in low-elevation ones (10 days). We found an overall lower density of newly assimilated C in treeline trees. The alpine treeline trees may have a photosynthetic compensatory mechanism to counteract the negative effects of the harsh treeline environment (e.g., lower temperature and shorter growing season) on C gain. Lower temperature at treeline may limit the sink activity and C downward transport via phloem, and shorter treeline growing season may result in early cessation of root growth, decreases sink strength, which all together lead to lower density of new C in the sink tissues and finally limit the growth of the alpine treeline trees.
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Affiliation(s)
- Yu Cong
- Key Laboratory of Geographical Processes and Ecological Security in Changbai Mountains, Ministry of Education, School of Geographical Sciences, Northeast Normal University, 5268 Renmin Street, Nanguan District, Changchun 130024, China
- Northeast Institute of Geography and Agricultural Ecology, Chinese Academy of Sciences, 4888 Shengbei Street, Kuancheng District, Changchun 130102, China
| | - Matthias Saurer
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse111, Birmensdorf CH-8903, Switzerland
| | - Edith Bai
- Key Laboratory of Geographical Processes and Ecological Security in Changbai Mountains, Ministry of Education, School of Geographical Sciences, Northeast Normal University, 5268 Renmin Street, Nanguan District, Changchun 130024, China
| | - Rolf Siegwolf
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse111, Birmensdorf CH-8903, Switzerland
| | - Arthur Gessler
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse111, Birmensdorf CH-8903, Switzerland
- Institute of Terrestrial Ecosystems, ETH Zurich, Universitaetsstrasse 16, Zurich 8092, Switzerland
| | - Kai Liu
- Key Laboratory of Geographical Processes and Ecological Security in Changbai Mountains, Ministry of Education, School of Geographical Sciences, Northeast Normal University, 5268 Renmin Street, Nanguan District, Changchun 130024, China
| | - Hudong Han
- Key Laboratory of Geographical Processes and Ecological Security in Changbai Mountains, Ministry of Education, School of Geographical Sciences, Northeast Normal University, 5268 Renmin Street, Nanguan District, Changchun 130024, China
| | - Yongcai Dang
- Key Laboratory of Geographical Processes and Ecological Security in Changbai Mountains, Ministry of Education, School of Geographical Sciences, Northeast Normal University, 5268 Renmin Street, Nanguan District, Changchun 130024, China
| | - Wenhua Xu
- Institute of Agricultural Resource and Environment, Jilin Academy of Agricultural Sciences, 1363 Shengtai Street, Nanguan District, Changchun 130033, China
- CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, 72 Wenhua Road, Shenhe District, Shenyang 110016, China
| | - Hong S He
- School of Natural Resources, University of Missouri, Columbia, MO 65211, USA
| | - Mai-He Li
- Key Laboratory of Geographical Processes and Ecological Security in Changbai Mountains, Ministry of Education, School of Geographical Sciences, Northeast Normal University, 5268 Renmin Street, Nanguan District, Changchun 130024, China
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse111, Birmensdorf CH-8903, Switzerland
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20
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Miao G, Noormets A, Gavazzi M, Mitra B, Domec JC, Sun G, McNulty S, King JS. Beyond carbon flux partitioning: Carbon allocation and nonstructural carbon dynamics inferred from continuous fluxes. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2022; 32:e2655. [PMID: 35567435 DOI: 10.1002/eap.2655] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 03/04/2022] [Accepted: 03/21/2022] [Indexed: 06/15/2023]
Abstract
Carbon (C) allocation and nonstructural carbon (NSC) dynamics play essential roles in plant growth and survival under stress and disturbance. However, quantitative understanding of these processes remains limited. Here we propose a framework where we connect commonly measured carbon cycle components (eddy covariance fluxes of canopy CO2 exchange, soil CO2 efflux, and allometry-based biomass and net primary production) by a simple mass balance model to derive ecosystem-level NSC dynamics (NSCi ), C translocation (dCi ), and the biomass production efficiency (BPEi ) in above- and belowground plant (i = agp and bgp) compartments. We applied this framework to two long-term monitored loblolly pine (Pinus taeda) plantations of different ages in North Carolina and characterized the variations of NSC and allocation in years under normal and drought conditions. The results indicated that the young stand did not have net NSC flux at the annual scale, whereas the mature stand stored a near-constant proportion of new assimilates as NSC every year under normal conditions, which was comparable in magnitude to new structural growth. Roots consumed NSC in drought and stored a significant amount of NSC post drought. The above- and belowground dCi and BPEi varied more from year to year in the young stand and approached a relatively stable pattern in the mature stand. The belowground BPEbgp differed the most between the young and mature stands and was most responsive to drought. With the internal C dynamics quantified, this framework may also improve biomass production estimation, which reveals the variations resulting from droughts. Overall, these quantified ecosystem-scale dynamics were consistent with existing evidence from tree-based manipulative experiments and measurements and demonstrated that combining the continuous fluxes as proposed here can provide additional information about plant internal C dynamics. Given that it is based on broadly available flux data, the proposed framework is promising to improve the allocation algorithms in ecosystem C cycle models and offers new insights into observed variability in soil-plant-climate interactions.
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Affiliation(s)
- Guofang Miao
- Fujian Provincial Key Laboratory for Subtropical Resources and Environment, Fujian Normal University, Fuzhou, Fujian Province, China
- School of Geographical Sciences, Fujian Normal University, Fuzhou, Fujian Province, China
- Department of Forestry and Environmental Resources, North Carolina State University, Raleigh, North Carolina, USA
| | - Asko Noormets
- Department of Forestry and Environmental Resources, North Carolina State University, Raleigh, North Carolina, USA
- Department of Ecosystem Science and Management, Texas A&M University, College Station, Texas, USA
| | - Michael Gavazzi
- Eastern Forest Environmental Threat Assessment Center, Southern Research Station, USDA Forest Service, Research Triangle Park, North Carolina, USA
| | - Bhaskar Mitra
- School of Informatics, Computing and Cyber Systems, Northern Arizona University, Flagstaff, Arizona, USA
| | - Jean-Christophe Domec
- Bordeaux Sciences AGRO, UMR1391 ISPA INRA, Gradignan Cedex, France
- Nicholas School of the Environment, Duke University, Durham, North Carolina, USA
| | - Ge Sun
- Eastern Forest Environmental Threat Assessment Center, Southern Research Station, USDA Forest Service, Research Triangle Park, North Carolina, USA
| | - Steve McNulty
- Eastern Forest Environmental Threat Assessment Center, Southern Research Station, USDA Forest Service, Research Triangle Park, North Carolina, USA
| | - John S King
- Department of Forestry and Environmental Resources, North Carolina State University, Raleigh, North Carolina, USA
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21
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Snyder KA, Robinson SA, Schmidt S, Hultine KR. Stable isotope approaches and opportunities for improving plant conservation. CONSERVATION PHYSIOLOGY 2022; 10:coac056. [PMID: 35966756 PMCID: PMC9367551 DOI: 10.1093/conphys/coac056] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 04/15/2021] [Accepted: 08/01/2022] [Indexed: 06/01/2023]
Abstract
Successful conservation of threatened species and ecosystems in a rapidly changing world requires scientifically sound decision-making tools that are readily accessible to conservation practitioners. Physiological applications that examine how plants and animals interact with their environment are now widely used when planning, implementing and monitoring conservation. Among these tools, stable-isotope physiology is a potentially powerful, yet under-utilized cornerstone of current and future conservation efforts of threatened and endangered plants. We review the underlying concepts and theory of stable-isotope physiology and describe how stable-isotope applications can support plant conservation. We focus on stable isotopes of carbon, hydrogen, oxygen and nitrogen to address plant ecophysiological responses to changing environmental conditions across temporal scales from hours to centuries. We review examples from a broad range of plant taxa, life forms and habitats and provide specific examples where stable-isotope analysis can directly improve conservation, in part by helping identify resilient, locally adapted genotypes or populations. Our review aims to provide a guide for practitioners to easily access and evaluate the information that can be derived from stable-isotope signatures, their limitations and how stable isotopes can improve conservation efforts.
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Affiliation(s)
- Keirith A Snyder
- Corresponding author: USDA Agricultural Research Service, Great Basin Rangelands Research Unit, Reno,
920 Valley Road, NV 89512, USA.
| | - Sharon A Robinson
- School of Earth, Atmospheric and Life Sciences, University of Wollongong, Wollongong, New South Wales 2522, Australia
- Securing Antarctica’s Environmental Future, University of Wollongong, Wollongong, New South Wales 2522, Australia
| | - Susanne Schmidt
- School of Agriculture and Food Sciences, The University of Queensland, Building 62, Brisbane Queensland 4075, Australia
| | - Kevin R Hultine
- Department of Research, Conservation and Collections, Desert Botanical Garden, 1201 Galvin Parkway, Phoenix, AZ 85008, USA
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22
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Brunn M, Hafner BD, Zwetsloot MJ, Weikl F, Pritsch K, Hikino K, Ruehr NK, Sayer EJ, Bauerle TL. Carbon allocation to root exudates is maintained in mature temperate tree species under drought. THE NEW PHYTOLOGIST 2022; 235:965-977. [PMID: 35403713 DOI: 10.1111/nph.18157] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 04/04/2022] [Indexed: 06/14/2023]
Abstract
Carbon (C) exuded via roots is proposed to increase under drought and facilitate important ecosystem functions. However, it is unknown how exudate quantities relate to the total C budget of a drought-stressed tree, that is, how much of net-C assimilation is allocated to exudation at the tree level. We calculated the proportion of daily C assimilation allocated to root exudation during early summer by collecting root exudates from mature Fagus sylvatica and Picea abies exposed to experimental drought, and combining above- and belowground C fluxes with leaf, stem and fine-root surface area. Exudation from individual roots increased exponentially with decreasing soil moisture, with the highest increase at the wilting point. Despite c. 50% reduced C assimilation under drought, exudation from fine-root systems was maintained and trees exuded 1.0% (F. sylvatica) to 2.5% (P. abies) of net C into the rhizosphere, increasing the proportion of C allocation to exudates two- to three-fold. Water-limited P. abies released two-thirds of its exudate C into the surface soil, whereas in droughted F. sylvatica it was only one-third. Across the entire root system, droughted trees maintained exudation similar to controls, suggesting drought-imposed belowground C investment, which could be beneficial for ecosystem resilience.
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Affiliation(s)
- Melanie Brunn
- iES Landau, Institute for Environmental Sciences, University of Koblenz-Landau, 76829, Landau, Germany
| | - Benjamin D Hafner
- School of Integrative Plant Science, Cornell University, Ithaca, NY, 14853, USA
| | - Marie J Zwetsloot
- Soil Biology Group, Wageningen University, 6708 PB, Wageningen, the Netherlands
| | - Fabian Weikl
- Institute of Biochemical Plant Pathology, Helmholtz Zentrum München GmbH - German Research Center for Environmental Health, 85764, Neuherberg, Germany
- TUM School of Life Sciences, Land Surface-Atmosphere Interactions, Ecophysiology of Plants, Technical University of Munich, 85354, Freising, Germany
| | - Karin Pritsch
- Institute of Biochemical Plant Pathology, Helmholtz Zentrum München GmbH - German Research Center for Environmental Health, 85764, Neuherberg, Germany
| | - Kyohsuke Hikino
- TUM School of Life Sciences, Land Surface-Atmosphere Interactions, Ecophysiology of Plants, Technical University of Munich, 85354, Freising, Germany
| | - Nadine K Ruehr
- Institute of Meteorology and Climate Research - Atmospheric Environmental Research (IMK-IFU), Karlsruhe Institute of Technology (KIT), 82467, Garmisch-Partenkirchen, Germany
| | - Emma J Sayer
- Lancaster Environment Centre, Lancaster University, LA1 4YQ, Lancaster, UK
| | - Taryn L Bauerle
- School of Integrative Plant Science, Cornell University, Ithaca, NY, 14853, USA
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23
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Yang Y, Ouyang S, Gessler A, Wang X, Na R, He HS, Wu Z, Li MH. Root Carbon Resources Determine Survival and Growth of Young Trees Under Long Drought in Combination With Fertilization. FRONTIERS IN PLANT SCIENCE 2022; 13:929855. [PMID: 35720584 PMCID: PMC9204053 DOI: 10.3389/fpls.2022.929855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Accepted: 05/13/2022] [Indexed: 06/15/2023]
Abstract
Current increases in not only the intensity and frequency but also the duration of drought events could affect the growth, physiology, and mortality of trees. We experimentally studied the effects of drought duration in combination with fertilization on leaf water potential, gas exchange, growth, tissue levels of non-structural carbohydrates (NSCs), tissue NSC consumption over-winter, and recovery after drought release in oak (Quercus petraea) and beech (Fagus sylvatica) saplings. Long drought duration (>1 month) decreased leaf water potential, photosynthesis, and NSC concentrations in both oak and beech saplings. Nitrogen fertilization did not mitigate the negative drought effects on both species. The photosynthesis and relative height increment recovered in the following rewetting year. Height growth in the rewetting year was significantly positively correlated with both pre- and post-winter root NSC levels. Root carbon reserve is critical for tree growth and survival under long-lasting drought. Our results indicate that beech is more sensitive to drought and fertilization than oak. The present study, in a physiological perspective, experimentally confirmed the view that the European beech, compared to oak, may be more strongly affected by future environmental changes.
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Affiliation(s)
- Yue Yang
- College of Ecology and Environment, Hainan University, Haikou, China
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
- Key Laboratory of Geographical Processes and Ecological Security in Changbai Mountains, Ministry of Education, School of Geographical Sciences, Northeast Normal University, Changchun, China
| | - Shengnan Ouyang
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
- Institute for Forest Resources and Environment Research Center of Guizhou Province, Guizhou University, Guiyang, China
| | - Arthur Gessler
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
- Institute of Terrestrial Ecosystems, ETH Zurich, Zurich, Switzerland
| | - Xiaoyu Wang
- Jiyang College of Zhejiang A and F University, Zhuji, China
| | - Risu Na
- School of Geographical Sciences, Inner Mongolia Normal University, Hohhot, China
| | - Hong S. He
- Key Laboratory of Geographical Processes and Ecological Security in Changbai Mountains, Ministry of Education, School of Geographical Sciences, Northeast Normal University, Changchun, China
- School of Natural Resources, University of Missouri, Columbia, MO, United States
| | - Zhengfang Wu
- Key Laboratory of Geographical Processes and Ecological Security in Changbai Mountains, Ministry of Education, School of Geographical Sciences, Northeast Normal University, Changchun, China
| | - Mai-He Li
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
- Key Laboratory of Geographical Processes and Ecological Security in Changbai Mountains, Ministry of Education, School of Geographical Sciences, Northeast Normal University, Changchun, China
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24
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Wang A, Lehmann MM, Rigling A, Gessler A, Saurer M, Du Z, Li MH. There Is No Carbon Transfer Between Scots Pine and Pine Mistletoe but the Assimilation Capacity of the Hemiparasite Is Constrained by Host Water Use Under Dry Conditions. FRONTIERS IN PLANT SCIENCE 2022; 13:902705. [PMID: 35720606 PMCID: PMC9201984 DOI: 10.3389/fpls.2022.902705] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 05/09/2022] [Indexed: 05/31/2023]
Abstract
Pine mistletoe is a hemiparasitic shrub that can produce its own photosynthates. There is a lack of knowledge about the interaction of mistletoe and host under varying environmental condition that might influence carbon gain and allocation. In a 13C-pulse labeling experiment with mature Pinus sylvestris (pine) infected by mistletoes grown in naturally dry or irrigated conditions, (1) mistletoe clusters were shielded from 13CO2 added, and (2) mistletoes or host needles were removed to manipulate the local assimilate and water availability. No 13C signal was found in shielded mistletoes, indicating no carbon transfer from the host to the mistletoe. When the pine needles were removed from girdled branches, no 13C signal was found in the host tissues, implying no carbon transfer from mistletoe to the host. However, mistletoes on needle-removed pine trees accumulated more labeled assimilates and had higher non-structural carbohydrate (NSC) concentrations only under naturally dry conditions but not in irrigated plots. Our results suggest that mistletoes show full carbon autonomy, as they neither receive carbon from nor provide carbon resource to the host trees. Moreover, the high assimilation capacity of mistletoes seems to be constrained by the host water use under dry conditions, suggesting that drought stress is not only negatively impacting trees but also mistletoes. Therefore, we conclude that the hemiparasites live on their own in terms of carbon gain which, however, depends on the water provided by the host tree.
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Affiliation(s)
- Ao Wang
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
- Institute of Terrestrial Ecosystems, ETH Zürich, Zurich, Switzerland
| | - Marco M Lehmann
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Andreas Rigling
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
- Institute of Terrestrial Ecosystems, ETH Zürich, Zurich, Switzerland
| | - Arthur Gessler
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
- Institute of Terrestrial Ecosystems, ETH Zürich, Zurich, Switzerland
| | - Matthias Saurer
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Zhong Du
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
- School of Geographical Sciences, China West Normal University, Nanchong, China
| | - Mai-He Li
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
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25
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Guidi C, Frey B, Brunner I, Meusburger K, Vogel ME, Chen X, Stucky T, Gwiazdowicz DJ, Skubała P, Bose AK, Schaub M, Rigling A, Hagedorn F. Soil fauna drives vertical redistribution of soil organic carbon in a long-term irrigated dry pine forest. GLOBAL CHANGE BIOLOGY 2022; 28:3145-3160. [PMID: 35124879 PMCID: PMC9306871 DOI: 10.1111/gcb.16122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 01/21/2022] [Accepted: 01/24/2022] [Indexed: 06/14/2023]
Abstract
Summer droughts strongly affect soil organic carbon (SOC) cycling, but net effects on SOC storage are unclear as drought affects both C inputs and outputs from soils. Here, we explored the overlooked role of soil fauna on SOC storage in forests, hypothesizing that soil faunal activity is particularly drought-sensitive, thereby reducing litter incorporation into the mineral soil and, eventually, long-term SOC storage. In a drought-prone pine forest (Switzerland), we performed a large-scale irrigation experiment for 17 years and assessed its impact on vertical SOC distribution and composition. We also examined litter mass loss of dominant tree species using different mesh-size litterbags and determined soil fauna abundance and community composition. The 17-year-long irrigation resulted in a C loss in the organic layers (-1.0 kg C m-2 ) and a comparable C gain in the mineral soil (+0.8 kg C m-2 ) and thus did not affect total SOC stocks. Irrigation increased the mass loss of Quercus pubescens and Viburnum lantana leaf litter, with greater effect sizes when meso- and macrofauna were included (+215%) than when excluded (+44%). The enhanced faunal-mediated litter mass loss was paralleled by a many-fold increase in the abundance of meso- and macrofauna during irrigation. Moreover, Acari and Collembola community composition shifted, with a higher presence of drought-sensitive species in irrigated soils. In comparison, microbial SOC mineralization was less sensitive to soil moisture. Our results suggest that the vertical redistribution of SOC with irrigation was mainly driven by faunal-mediated litter incorporation, together with increased root C inputs. Our study shows that soil fauna is highly sensitive to natural drought, which leads to a reduced C transfer from organic layers to the mineral soil. In the longer term, this potentially affects SOC storage and, therefore, soil fauna plays a key but so far largely overlooked role in shaping SOC responses to drought.
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Affiliation(s)
- Claudia Guidi
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
| | - Beat Frey
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
| | - Ivano Brunner
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
| | - Katrin Meusburger
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
| | - Michael E. Vogel
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
| | - Xiaomei Chen
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
- Present address:
School of Geography and Remote SensingGuangzhou UniversityGuangzhouChina
| | - Tobias Stucky
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
| | | | - Piotr Skubała
- Faculty of Natural SciencesUniversity of Silesia in KatowiceKatowicePoland
| | - Arun K. Bose
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
- Forestry and Wood Technology DisciplineKhulna UniversityKhulnaBangladesh
| | - Marcus Schaub
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
| | - Andreas Rigling
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
- Institute of Terrestrial EcosystemsETH ZurichZürichSwitzerland
| | - Frank Hagedorn
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
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26
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Schönbeck L, Grossiord C, Gessler A, Gisler J, Meusburger K, D'Odorico P, Rigling A, Salmon Y, Stocker BD, Zweifel R, Schaub M. Photosynthetic acclimation and sensitivity to short- and long-term environmental changes in a drought-prone forest. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:2576-2588. [PMID: 35134157 DOI: 10.1093/jxb/erac033] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 01/31/2022] [Indexed: 06/14/2023]
Abstract
Future climate will be characterized by an increase in frequency and duration of drought and warming that exacerbates atmospheric evaporative demand. How trees acclimate to long-term soil moisture changes and whether these long-term changes alter trees' sensitivity to short-term (day to months) variations of vapor pressure deficit (VPD) and soil moisture is largely unknown. Leaf gas exchange measurements were performed within a long-term (17 years) irrigation experiment in a drought-prone Scots pine-dominated forest in one of Switzerland's driest areas on trees in naturally dry (control), irrigated, and 'irrigation-stop' (after 11 years of irrigation) conditions. Seventeen years of irrigation increased photosynthesis (A) and stomatal conductance (gs) and reduced gs sensitivity to increasing VPD and soil drying. Following irrigation-stop, gas exchange decreased only after 3 years. After 5 years, maximum carboxylation (Vcmax) and electron transport (Jmax) rates in irrigation-stop recovered to similar levels as to before the irrigation-stop. These results suggest that long-term release from soil drought reduces the sensitivity to VPD and that atmospheric constraints may play an increasingly important role in combination with soil drought. Moreover, our study indicates that structural adjustments lead to an attenuation of initially strong leaf-level acclimation to strong multiple-year drought.
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Affiliation(s)
- Leonie Schönbeck
- Plant Ecology Research Laboratory, School of Architecture, Civil and Environmental Engineering, EPFL, Station 2, 1015 Lausanne, Switzerland
- Functional Plant Ecology, Community Ecology Unit, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Station 2, 1015 Lausanne, Switzerland
| | - Charlotte Grossiord
- Plant Ecology Research Laboratory, School of Architecture, Civil and Environmental Engineering, EPFL, Station 2, 1015 Lausanne, Switzerland
- Functional Plant Ecology, Community Ecology Unit, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Station 2, 1015 Lausanne, Switzerland
| | - Arthur Gessler
- Forest Dynamics Research Unit, Swiss Federal Research Institute for Forest, Snow and Landscape Research WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
- Department of Environmental Systems Science, ETH Zürich, Universitätstrasse 2, 8092 Zürich, Switzerland
| | - Jonas Gisler
- Forest Dynamics Research Unit, Swiss Federal Research Institute for Forest, Snow and Landscape Research WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
| | - Katrin Meusburger
- Biogeochemistry Unit, Swiss Federal Research Institute for Forest, Snow and Landscape research WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
| | - Petra D'Odorico
- Forest Dynamics Research Unit, Swiss Federal Research Institute for Forest, Snow and Landscape Research WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
| | - Andreas Rigling
- Forest Dynamics Research Unit, Swiss Federal Research Institute for Forest, Snow and Landscape Research WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
- Department of Environmental Systems Science, ETH Zürich, Universitätstrasse 2, 8092 Zürich, Switzerland
| | - Yann Salmon
- Institute for Atmospheric and Earth System Research/Forest Sciences, University of Helsinki, PO Box 27, 00014 University of Helsinki, Finland
- Institute for Atmospheric and Earth System Research/Physics, University of Helsinki, PO Box 68, 00014 University of Helsinki, Finland
| | - Benjamin D Stocker
- Forest Dynamics Research Unit, Swiss Federal Research Institute for Forest, Snow and Landscape Research WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
- Department of Environmental Systems Science, ETH Zürich, Universitätstrasse 2, 8092 Zürich, Switzerland
| | - Roman Zweifel
- Forest Dynamics Research Unit, Swiss Federal Research Institute for Forest, Snow and Landscape Research WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
| | - Marcus Schaub
- Forest Dynamics Research Unit, Swiss Federal Research Institute for Forest, Snow and Landscape Research WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
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27
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Hikino K, Danzberger J, Riedel VP, Rehschuh R, Ruehr NK, Hesse BD, Lehmann MM, Buegger F, Weikl F, Pritsch K, Grams TEE. High resilience of carbon transport in long-term drought-stressed mature Norway spruce trees within 2 weeks after drought release. GLOBAL CHANGE BIOLOGY 2022; 28:2095-2110. [PMID: 34927319 DOI: 10.1111/gcb.16051] [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: 06/08/2021] [Accepted: 11/29/2021] [Indexed: 06/14/2023]
Abstract
Under ongoing global climate change, drought periods are predicted to increase in frequency and intensity in the future. Under these circumstances, it is crucial for tree's survival to recover their restricted functionalities quickly after drought release. To elucidate the recovery of carbon (C) transport rates in c. 70-year-old Norway spruce (Picea abies [L.] KARST.) after 5 years of recurrent summer droughts, we conducted a continuous whole-tree 13 C labeling experiment in parallel with watering. We determined the arrival time of current photoassimilates in major C sinks by tracing the 13 C label in stem and soil CO2 efflux, and tips of living fine roots. In the first week after watering, aboveground C transport rates (CTR) from crown to trunk base were still 50% lower in previously drought-stressed trees (0.16 ± 0.01 m h-1 ) compared to controls (0.30 ± 0.06 m h-1 ). Conversely, CTR below ground, that is, from the trunk base to soil CO2 efflux were already similar between treatments (c. 0.03 m h-1 ). Two weeks after watering, aboveground C transport of previously drought-stressed trees recovered to the level of the controls. Furthermore, regrowth of water-absorbing fine roots upon watering was supported by faster incorporation of 13 C label in previously drought-stressed (within 12 ± 10 h upon arrival at trunk base) compared to control trees (73 ± 10 h). Thus, the whole-tree C transport system from the crown to soil CO2 efflux fully recovered within 2 weeks after drought release, and hence showed high resilience to recurrent summer droughts in mature Norway spruce forests. This high resilience of the C transport system is an important prerequisite for the recovery of other tree functionalities and productivity.
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Affiliation(s)
- Kyohsuke Hikino
- Technical University of Munich (TUM), TUM School of Life Sciences, Land Surface-Atmosphere Interactions, Ecophysiology of Plants, Freising, Germany
| | - Jasmin Danzberger
- Helmholtz Zentrum München - German Research Center for Environmental Health (GmbH), Institute of Biochemical Plant Pathology, Neuherberg, Germany
| | - Vincent P Riedel
- Technical University of Munich (TUM), TUM School of Life Sciences, Land Surface-Atmosphere Interactions, Ecophysiology of Plants, Freising, Germany
| | - Romy Rehschuh
- Karlsruhe Institute of Technology, Institute of Meteorology and Climate Research-Atmospheric Environmental Research (KIT/IMK-IFU), Garmisch-Partenkirchen, Germany
| | - Nadine K Ruehr
- Karlsruhe Institute of Technology, Institute of Meteorology and Climate Research-Atmospheric Environmental Research (KIT/IMK-IFU), Garmisch-Partenkirchen, Germany
| | - Benjamin D Hesse
- Technical University of Munich (TUM), TUM School of Life Sciences, Land Surface-Atmosphere Interactions, Ecophysiology of Plants, Freising, Germany
| | - Marco M Lehmann
- Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Forest Dynamics, Birmensdorf, Switzerland
| | - Franz Buegger
- Helmholtz Zentrum München - German Research Center for Environmental Health (GmbH), Institute of Biochemical Plant Pathology, Neuherberg, Germany
| | - Fabian Weikl
- Technical University of Munich (TUM), TUM School of Life Sciences, Land Surface-Atmosphere Interactions, Ecophysiology of Plants, Freising, Germany
- Helmholtz Zentrum München - German Research Center for Environmental Health (GmbH), Institute of Biochemical Plant Pathology, Neuherberg, Germany
| | - Karin Pritsch
- Helmholtz Zentrum München - German Research Center for Environmental Health (GmbH), Institute of Biochemical Plant Pathology, Neuherberg, Germany
| | - Thorsten E E Grams
- Technical University of Munich (TUM), TUM School of Life Sciences, Land Surface-Atmosphere Interactions, Ecophysiology of Plants, Freising, Germany
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28
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Bose AK, Rigling A, Gessler A, Hagedorn F, Brunner I, Feichtinger L, Bigler C, Egli S, Etzold S, Gossner MM, Guidi C, Lévesque M, Meusburger K, Peter M, Saurer M, Scherrer D, Schleppi P, Schönbeck L, Vogel ME, Arx G, Wermelinger B, Wohlgemuth T, Zweifel R, Schaub M. Lessons learned from a long‐term irrigation experiment in a dry Scots pine forest: Impacts on traits and functioning. ECOL MONOGR 2022. [DOI: 10.1002/ecm.1507] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Arun K. Bose
- Swiss Federal Research Institute WSL, Zürcherstrasse 111 Birmensdorf Switzerland
- Forestry and Wood Technology Discipline Khulna University Khulna Bangladesh
| | - Andreas Rigling
- Swiss Federal Research Institute WSL, Zürcherstrasse 111 Birmensdorf Switzerland
- Institute of Terrestrial Ecosystems ETH Zurich, Universitätstrasse 16 Zurich Switzerland
| | - Arthur Gessler
- Swiss Federal Research Institute WSL, Zürcherstrasse 111 Birmensdorf Switzerland
- Institute of Terrestrial Ecosystems ETH Zurich, Universitätstrasse 16 Zurich Switzerland
| | - Frank Hagedorn
- Swiss Federal Research Institute WSL, Zürcherstrasse 111 Birmensdorf Switzerland
| | - Ivano Brunner
- Swiss Federal Research Institute WSL, Zürcherstrasse 111 Birmensdorf Switzerland
| | - Linda Feichtinger
- Swiss Federal Research Institute WSL, Zürcherstrasse 111 Birmensdorf Switzerland
| | - Christof Bigler
- Department of Environmental Systems Science, Forest Ecology, Universitätstrasse 22 ETH Zurich Zurich Switzerland
| | - Simon Egli
- Swiss Federal Research Institute WSL, Zürcherstrasse 111 Birmensdorf Switzerland
| | - Sophia Etzold
- Swiss Federal Research Institute WSL, Zürcherstrasse 111 Birmensdorf Switzerland
| | - Martin M. Gossner
- Swiss Federal Research Institute WSL, Zürcherstrasse 111 Birmensdorf Switzerland
- Institute of Terrestrial Ecosystems ETH Zurich, Universitätstrasse 16 Zurich Switzerland
| | - Claudia Guidi
- Swiss Federal Research Institute WSL, Zürcherstrasse 111 Birmensdorf Switzerland
| | - Mathieu Lévesque
- Department of Environmental Systems Science, Forest Ecology, Universitätstrasse 22 ETH Zurich Zurich Switzerland
| | - Katrin Meusburger
- Swiss Federal Research Institute WSL, Zürcherstrasse 111 Birmensdorf Switzerland
| | - Martina Peter
- Swiss Federal Research Institute WSL, Zürcherstrasse 111 Birmensdorf Switzerland
| | - Matthias Saurer
- Swiss Federal Research Institute WSL, Zürcherstrasse 111 Birmensdorf Switzerland
| | - Daniel Scherrer
- Swiss Federal Research Institute WSL, Zürcherstrasse 111 Birmensdorf Switzerland
| | - Patrick Schleppi
- Swiss Federal Research Institute WSL, Zürcherstrasse 111 Birmensdorf Switzerland
| | - Leonie Schönbeck
- Swiss Federal Research Institute WSL, Zürcherstrasse 111 Birmensdorf Switzerland
- Plant Ecology Research Laboratory, School of Architecture, Civil and Environmental Engineering ENAC École Polytechnique Fédérale de Lausanne EPFL, Station 2 Lausanne Switzerland
| | - Michael E. Vogel
- Swiss Federal Research Institute WSL, Zürcherstrasse 111 Birmensdorf Switzerland
| | - Georg Arx
- Swiss Federal Research Institute WSL, Zürcherstrasse 111 Birmensdorf Switzerland
| | - Beat Wermelinger
- Swiss Federal Research Institute WSL, Zürcherstrasse 111 Birmensdorf Switzerland
| | - Thomas Wohlgemuth
- Swiss Federal Research Institute WSL, Zürcherstrasse 111 Birmensdorf Switzerland
| | - Roman Zweifel
- Swiss Federal Research Institute WSL, Zürcherstrasse 111 Birmensdorf Switzerland
| | - Marcus Schaub
- Swiss Federal Research Institute WSL, Zürcherstrasse 111 Birmensdorf Switzerland
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29
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Gessler A, Bächli L, Rouholahnejad Freund E, Treydte K, Schaub M, Haeni M, Weiler M, Seeger S, Marshall J, Hug C, Zweifel R, Hagedorn F, Rigling A, Saurer M, Meusburger K. Drought reduces water uptake in beech from the drying topsoil, but no compensatory uptake occurs from deeper soil layers. THE NEW PHYTOLOGIST 2022; 233:194-206. [PMID: 34610146 PMCID: PMC9293437 DOI: 10.1111/nph.17767] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 09/26/2021] [Indexed: 06/02/2023]
Abstract
The intensity and frequency of droughts events are projected to increase in future with expected adverse effects for forests. Thus, information on the dynamics of tree water uptake from different soil layers during and after drought is crucial. We applied an in situ water isotopologue monitoring system to determine the oxygen isotope composition in soil and xylem water of European beech with a 2-h resolution together with measurements of soil water content, transpiration and tree water deficit. Using a Bayesian isotope mixing model, we inferred the relative and absolute contribution of water from four different soil layers to tree water use. Beech took up more than 50% of its water from the uppermost 5 cm soil layer at the beginning of the 2018 drought, but then reduced absolute water uptake from the drying topsoil by 84%. The trees were not able to quantitatively compensate for restricted topsoil water availability by additional uptake from deeper soil layers, which is related to the fine root depth distribution. Absolute water uptake from the topsoil was restored to pre-drought levels within 3 wk after rewetting. These uptake patterns help to explain both the drought sensitivity of beech and its high recovery potential after drought release.
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Affiliation(s)
- Arthur Gessler
- Research Unit Forest DynamicsSwiss Federal Research Institute for Forest, Snow and Landscape Research WSL8903BirmensdorfSwitzerland
- Institute of Terrestrial EcosystemsETH Zurich8092ZurichSwitzerland
| | - Lukas Bächli
- Research Unit Forest DynamicsSwiss Federal Research Institute for Forest, Snow and Landscape Research WSL8903BirmensdorfSwitzerland
| | | | - Kerstin Treydte
- Research Unit Forest DynamicsSwiss Federal Research Institute for Forest, Snow and Landscape Research WSL8903BirmensdorfSwitzerland
| | - Marcus Schaub
- Research Unit Forest DynamicsSwiss Federal Research Institute for Forest, Snow and Landscape Research WSL8903BirmensdorfSwitzerland
| | - Matthias Haeni
- Research Unit Forest DynamicsSwiss Federal Research Institute for Forest, Snow and Landscape Research WSL8903BirmensdorfSwitzerland
| | - Markus Weiler
- Hydrology, Faculty of Environment and Natural ResourcesUniversity of Freiburg79098FreiburgGermany
| | - Stefan Seeger
- Hydrology, Faculty of Environment and Natural ResourcesUniversity of Freiburg79098FreiburgGermany
| | - John Marshall
- Department of Forest Ecology and ManagementSwedish University of Agricultural SciencesUmeå90283Sweden
| | - Christian Hug
- Research Unit Forest DynamicsSwiss Federal Research Institute for Forest, Snow and Landscape Research WSL8903BirmensdorfSwitzerland
| | - Roman Zweifel
- Research Unit Forest DynamicsSwiss Federal Research Institute for Forest, Snow and Landscape Research WSL8903BirmensdorfSwitzerland
| | - Frank Hagedorn
- Research Unit Forest Soils and BiogeochemistrySwiss Federal Research Institute for Forest, Snow and Landscape Research WSL8903BirmensdorfSwitzerland
| | - Andreas Rigling
- Research Unit Forest DynamicsSwiss Federal Research Institute for Forest, Snow and Landscape Research WSL8903BirmensdorfSwitzerland
- Institute of Terrestrial EcosystemsETH Zurich8092ZurichSwitzerland
| | - Matthias Saurer
- Research Unit Forest DynamicsSwiss Federal Research Institute for Forest, Snow and Landscape Research WSL8903BirmensdorfSwitzerland
| | - Katrin Meusburger
- Research Unit Forest Soils and BiogeochemistrySwiss Federal Research Institute for Forest, Snow and Landscape Research WSL8903BirmensdorfSwitzerland
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30
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Rehschuh R, Rehschuh S, Gast A, Jakab AL, Lehmann MM, Saurer M, Gessler A, Ruehr NK. Tree allocation dynamics beyond heat and hot drought stress reveal changes in carbon storage, belowground translocation and growth. THE NEW PHYTOLOGIST 2022; 233:687-704. [PMID: 34668198 DOI: 10.1111/nph.17815] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 10/12/2021] [Indexed: 06/13/2023]
Abstract
Heatwaves combined with drought affect tree functioning with as yet undetermined legacy effects on carbon (C) and nitrogen (N) allocation. We continuously monitored shoot and root gas exchange, δ13 CO2 of respiration and stem growth in well-watered and drought-treated Pinus sylvestris (Scots pine) seedlings exposed to increasing daytime temperatures (max. 42°C) and evaporative demand. Following stress release, we used 13 CO2 canopy pulse-labeling, supplemented by soil-applied 15 N, to determine allocation to plant compartments, respiration and soil microbial biomass (SMB) over 2.5 wk. Previously heat-treated seedlings rapidly translocated 13 C along the long-distance transport path, to root respiration (Rroot ; 7.1 h) and SMB (3 d). Furthermore, 13 C accumulated in branch cellulose, suggesting secondary growth enhancement. However, in recovering drought-heat seedlings, the mean residence time of 13 C in needles increased, whereas C translocation to Rroot was delayed (13.8 h) and 13 C incorporated into starch rather than cellulose. Concurrently, we observed stress-induced low N uptake and aboveground allocation. C and N allocation during early recovery were affected by stress type and impact. Although C uptake increased quickly in both treatments, drought-heat in combination reduced the above-belowground coupling and starch accumulated in leaves at the expense of growth. Accordingly, C allocation during recovery depends on phloem translocation capacity.
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Affiliation(s)
- Romy Rehschuh
- Karlsruhe Institute of Technology (KIT), Institute of Meteorology and Climate Research - Atmospheric Environmental Research (IMK-IFU), Garmisch-Partenkirchen, 82467, Germany
| | - Stephanie Rehschuh
- Karlsruhe Institute of Technology (KIT), Institute of Meteorology and Climate Research - Atmospheric Environmental Research (IMK-IFU), Garmisch-Partenkirchen, 82467, Germany
| | - Andreas Gast
- Karlsruhe Institute of Technology (KIT), Institute of Meteorology and Climate Research - Atmospheric Environmental Research (IMK-IFU), Garmisch-Partenkirchen, 82467, Germany
| | - Andrea-Livia Jakab
- Karlsruhe Institute of Technology (KIT), Institute of Meteorology and Climate Research - Atmospheric Environmental Research (IMK-IFU), Garmisch-Partenkirchen, 82467, Germany
| | - Marco M Lehmann
- Swiss Federal Research Institute WSL, Research Unit Forest Dynamics, Birmensdorf, 8903, Switzerland
| | - Matthias Saurer
- Swiss Federal Research Institute WSL, Research Unit Forest Dynamics, Birmensdorf, 8903, Switzerland
| | - Arthur Gessler
- Swiss Federal Research Institute WSL, Research Unit Forest Dynamics, Birmensdorf, 8903, Switzerland
- Department of Environmental System Sciences, ETH Zurich, Zurich, 8092, Switzerland
| | - Nadine K Ruehr
- Karlsruhe Institute of Technology (KIT), Institute of Meteorology and Climate Research - Atmospheric Environmental Research (IMK-IFU), Garmisch-Partenkirchen, 82467, Germany
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31
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Werner C, Meredith LK, Ladd SN, Ingrisch J, Kübert A, van Haren J, Bahn M, Bailey K, Bamberger I, Beyer M, Blomdahl D, Byron J, Daber E, Deleeuw J, Dippold MA, Fudyma J, Gil-Loaiza J, Honeker LK, Hu J, Huang J, Klüpfel T, Krechmer J, Kreuzwieser J, Kühnhammer K, Lehmann MM, Meeran K, Misztal PK, Ng WR, Pfannerstill E, Pugliese G, Purser G, Roscioli J, Shi L, Tfaily M, Williams J. Ecosystem fluxes during drought and recovery in an experimental forest. Science 2021; 374:1514-1518. [PMID: 34914503 DOI: 10.1126/science.abj6789] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
[Figure: see text].
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Affiliation(s)
- Christiane Werner
- Ecosystem Physiology, Faculty of Environment and Natural Resources, Albert-Ludwig-University of Freiburg, Freiburg, Germany
| | - Laura K Meredith
- School of Natural Resources and the Environment, University of Arizona, Tucson, AZ, USA.,Biosphere 2, University of Arizona, Oracle, AZ, USA.,BIO5 Institute, The University of Arizona, Tucson, AZ, USA
| | - S Nemiah Ladd
- Ecosystem Physiology, Faculty of Environment and Natural Resources, Albert-Ludwig-University of Freiburg, Freiburg, Germany
| | - Johannes Ingrisch
- Ecosystem Physiology, Faculty of Environment and Natural Resources, Albert-Ludwig-University of Freiburg, Freiburg, Germany.,Department of Ecology, University of Innsbruck, Innsbruck, Austria
| | - Angelika Kübert
- Ecosystem Physiology, Faculty of Environment and Natural Resources, Albert-Ludwig-University of Freiburg, Freiburg, Germany
| | - Joost van Haren
- Biosphere 2, University of Arizona, Oracle, AZ, USA.,Honors College, University of Arizona, Tucson, AZ, USA
| | - Michael Bahn
- Department of Ecology, University of Innsbruck, Innsbruck, Austria
| | - Kinzie Bailey
- School of Natural Resources and the Environment, University of Arizona, Tucson, AZ, USA
| | - Ines Bamberger
- Ecosystem Physiology, Faculty of Environment and Natural Resources, Albert-Ludwig-University of Freiburg, Freiburg, Germany
| | - Matthias Beyer
- Institute of Geoecology - Environmental Geochemistry, Technical University Braunschweig, Braunschweig, Germany
| | - Daniel Blomdahl
- Department of Civil, Architectural and Environmental Engineering, University of Texas at Austin, Austin, TX, USA
| | - Joseph Byron
- Department of Atmospheric Chemistry, Max Planck Institute for Chemistry, Mainz, Germany
| | - Erik Daber
- Ecosystem Physiology, Faculty of Environment and Natural Resources, Albert-Ludwig-University of Freiburg, Freiburg, Germany
| | | | - Michaela A Dippold
- Biogeochemistry of Agroecosystems, University of Göttingen, Göttingen, Germany.,Geo-Biosphere Interactions, University of Tuebingen, Tuebingen, Germany
| | - Jane Fudyma
- Department of Environmental Science, University of Arizona, Tucson, AZ, USA
| | - Juliana Gil-Loaiza
- School of Natural Resources and the Environment, University of Arizona, Tucson, AZ, USA
| | | | - Jia Hu
- School of Natural Resources and the Environment, University of Arizona, Tucson, AZ, USA
| | - Jianbei Huang
- Max Planck Institute for Biogeochemistry, Jena, Germany
| | - Thomas Klüpfel
- Department of Atmospheric Chemistry, Max Planck Institute for Chemistry, Mainz, Germany
| | | | - Jürgen Kreuzwieser
- Ecosystem Physiology, Faculty of Environment and Natural Resources, Albert-Ludwig-University of Freiburg, Freiburg, Germany
| | - Kathrin Kühnhammer
- Ecosystem Physiology, Faculty of Environment and Natural Resources, Albert-Ludwig-University of Freiburg, Freiburg, Germany.,Institute of Geoecology - Environmental Geochemistry, Technical University Braunschweig, Braunschweig, Germany
| | - Marco M Lehmann
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Birmensdorf, Switzerland
| | | | - Pawel K Misztal
- Department of Civil, Architectural and Environmental Engineering, University of Texas at Austin, Austin, TX, USA
| | - Wei-Ren Ng
- Biosphere 2, University of Arizona, Oracle, AZ, USA
| | - Eva Pfannerstill
- Department of Atmospheric Chemistry, Max Planck Institute for Chemistry, Mainz, Germany
| | - Giovanni Pugliese
- Ecosystem Physiology, Faculty of Environment and Natural Resources, Albert-Ludwig-University of Freiburg, Freiburg, Germany.,Department of Atmospheric Chemistry, Max Planck Institute for Chemistry, Mainz, Germany
| | - Gemma Purser
- Centre for Ecology and Hydrology, University of Edinburgh, Edinburgh, UK
| | | | - Lingling Shi
- Biogeochemistry of Agroecosystems, University of Göttingen, Göttingen, Germany.,Geo-Biosphere Interactions, University of Tuebingen, Tuebingen, Germany
| | - Malak Tfaily
- BIO5 Institute, The University of Arizona, Tucson, AZ, USA.,Geo-Biosphere Interactions, University of Tuebingen, Tuebingen, Germany.,Pacific Northwest National Laboratory, Richland, WA, USA
| | - Jonathan Williams
- Department of Atmospheric Chemistry, Max Planck Institute for Chemistry, Mainz, Germany.,Energy, Environment and Water Research Center, The Cyprus Institute, Nicosia, Cyprus
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32
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Gao D, Joseph J, Werner RA, Brunner I, Zürcher A, Hug C, Wang A, Zhao C, Bai E, Meusburger K, Gessler A, Hagedorn F. Drought alters the carbon footprint of trees in soils-tracking the spatio-temporal fate of 13 C-labelled assimilates in the soil of an old-growth pine forest. GLOBAL CHANGE BIOLOGY 2021; 27:2491-2506. [PMID: 33739617 PMCID: PMC8251913 DOI: 10.1111/gcb.15557] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 01/22/2021] [Accepted: 02/03/2021] [Indexed: 05/04/2023]
Abstract
Above and belowground compartments in ecosystems are closely coupled on daily to annual timescales. In mature forests, this interlinkage and how it is impacted by drought is still poorly understood. Here, we pulse-labelled 100-year-old trees with 13 CO2 within a 15-year-long irrigation experiment in a naturally dry pine forest to quantify how drought regime affects the transfer and use of assimilates from trees to the rhizosphere and associated microbial communities. It took 4 days until new 13 C-labelled assimilates were allocated to the rhizosphere. One year later, the 13 C signal of the 3-h long pulse labelling was still detectable in stem and soil respiration, which provides evidence that parts of the assimilates are stored in trees before they are used for metabolic processes in the rhizosphere. Irrigation removing the natural water stress reduced the mean C residence time from canopy uptake until soil respiration from 89 to 40 days. Moreover, irrigation increased the amount of assimilates transferred to and respired in the soil within the first 10 days by 370%. A small precipitation event rewetting surface soils altered this pattern rapidly and reduced the effect size to +35%. Microbial biomass incorporated 46 ± 5% and 31 ± 7% of the C used in the rhizosphere in the dry control and irrigation treatment respectively. Mapping the spatial distribution of soil-respired 13 CO2 around the 10 pulse-labelled trees showed that tree rhizospheres extended laterally 2.8 times beyond tree canopies, implying that there is a strong overlap of the rhizosphere among adjacent trees. Irrigation increased the rhizosphere area by 60%, which gives evidence of a long-term acclimation of trees and their rhizosphere to the drought regime. The moisture-sensitive transfer and use of C in the rhizosphere has consequences for C allocation within trees, soil microbial communities and soil carbon storage.
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Affiliation(s)
- Decai Gao
- Swiss Federal Research Institute WSLBirmensdorfSwitzerland
- Key Laboratory of Geographical Processes and Ecological Security of Changbai MountainsMinistry of EducationNortheast Normal UniversityChangchunChina
| | - Jobin Joseph
- Swiss Federal Research Institute WSLBirmensdorfSwitzerland
| | - Roland A Werner
- Department of Environmental Systems ScienceETH ZurichZurichSwitzerland
| | - Ivano Brunner
- Swiss Federal Research Institute WSLBirmensdorfSwitzerland
| | - Alois Zürcher
- Swiss Federal Research Institute WSLBirmensdorfSwitzerland
| | - Christian Hug
- Swiss Federal Research Institute WSLBirmensdorfSwitzerland
| | - Ao Wang
- Swiss Federal Research Institute WSLBirmensdorfSwitzerland
- Terrestrial EcosystemsETH ZurichZurichSwitzerland
| | - Chunhong Zhao
- Key Laboratory of Geographical Processes and Ecological Security of Changbai MountainsMinistry of EducationNortheast Normal UniversityChangchunChina
| | - Edith Bai
- Key Laboratory of Geographical Processes and Ecological Security of Changbai MountainsMinistry of EducationNortheast Normal UniversityChangchunChina
| | | | - Arthur Gessler
- Swiss Federal Research Institute WSLBirmensdorfSwitzerland
- Terrestrial EcosystemsETH ZurichZurichSwitzerland
| | - Frank Hagedorn
- Swiss Federal Research Institute WSLBirmensdorfSwitzerland
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