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Zhao L, Liu X, Wang N, Barbeta A, Zhang Y, Cernusak LA, Wang L. The determining factors of hydrogen isotope offsets between plants and their source waters. New Phytol 2024; 241:2009-2024. [PMID: 38178796 DOI: 10.1111/nph.19492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Accepted: 11/22/2023] [Indexed: 01/06/2024]
Abstract
A fundamental assumption when using hydrogen and oxygen stable isotopes to understand ecohydrological processes is that no isotope fractionation occurs during plant water uptake/transport/redistribution. A growing body of evidence has indicated that hydrogen isotope fractionation occurs in certain environments or for certain plant species. However, whether the plant water source hydrogen isotope offset (δ2 H offset) is a common phenomenon and how it varies among different climates and plant functional types remains unclear. Here, we demonstrated the presence of positive, negative, and zero offsets based on extensive observations of 12 plant species of 635 paired stable isotopic compositions along a strong climate gradient within an inland river basin. Both temperature and relative humidity affected δ2 H offsets. In cool and moist environments, temperature mainly affected δ2 H offsets negatively due to its role in physiological activity. In warm and dry environments, relative humidity mainly affected δ2 H offsets, likely by impacting plant leaf stomatal conductance. These δ2 H offsets also showed substantial linkages with leaf water 18 O enrichment, an indicator of transpiration and evaporative demand. Further studies focusing on the ecophysiological and biochemical understanding of plant δ2 H dynamics under specific environments are essential for understanding regional ecohydrological processes and for conducting paleoclimate reconstructions.
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Affiliation(s)
- Liangju Zhao
- Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity, College of Urban and Environmental Sciences, Northwest University, Xi'an, 710069, China
| | - Xiaohong Liu
- School of Geography and Tourism, Shaanxi Normal University, Xi'an, 710119, China
| | - Ninglian Wang
- Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity, College of Urban and Environmental Sciences, Northwest University, Xi'an, 710069, China
| | - Adrià Barbeta
- BEECA, Department of Evolutionary Biology, Ecology and Environmental Sciences, Universitat de Barcelona, Barcelona, Catalonia, 08007, Spain
| | - Yu Zhang
- School of Geography and Tourism, Shaanxi Normal University, Xi'an, 710119, China
| | - Lucas A Cernusak
- College of Science and Engineering, James Cook University, Cairns, QLD, 4878, Australia
| | - Lixin Wang
- Department of Earth and Environmental Sciences, Indiana University Indianapolis (IUI), Indianapolis, IN, 46202, USA
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El-Shenawy MI, Herwartz D, Staubwasser M. A passive method for sampling water in the soil-plant-atmosphere continuum for stable hydrogen and oxygen isotope analyses. Rapid Commun Mass Spectrom 2024; 38:e9646. [PMID: 38124170 DOI: 10.1002/rcm.9646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 09/12/2023] [Accepted: 09/14/2023] [Indexed: 12/23/2023]
Abstract
RATIONALE Hydrogen and oxygen isotopes in water molecules are powerful tools to constrain the dynamics of water cycling within the soil-plant-atmosphere continuum (SPAC). However, the recovery of water from the SPAC requires logistical arrangements and implementation of different time- and cost-consuming techniques in either the field or the laboratory. METHODS We developed a passive method to sample water from the three compartments of the SPAC by using a hygroscopic salt of a high water absorbance capacity (CaCl2 ). This method allows either H2 O(V) -H2 O(L) isotope equilibration in the case of infinite water reservoir (atmospheric water vapor (WV)) or quantitative absorption of water from a finite water reservoir (e.g. soil and plants). The water absorbed by CaCl2 was distilled first and subsequently processed for hydrogen and triple oxygen isotope mass spectrometry analyses. The distillation step can be bypassed when employing isotope analytical techniques that are based on equilibration. RESULTS Our experiments show that anhydrous CaCl2 absorbs WV of 210 ± 6% and 130 ± 6% of its dry weight from an infinite WV reservoir at relative humidity of 60% and 30%, respectively. Chemical and isotope equilibrations between WV and absorbed water were attained within 3 days at room temperature, enabling the back-calculation of the isotope composition of atmospheric WV. Preliminary experiments to extract water from plant and sand (i.e. finite WV reservoir) demonstrate a quasi-complete recovery of water in these matrices without significant isotope fractionation. The reproducibility of our method is better than 1.6‰, 0.32‰, 0.17‰ and 6‰ per meg for δ2 H, δ18 O, δ17 O and 17 O-excess. CONCLUSIONS The CaCl2 -H2 O absorption (passive) method requires very limited logistics in the field facilitating spatial and temporal water vapor/water sampling from atmosphere and soil at low resolution (i.e. average of 3-5 days). Moreover, it allows high sample throughput for the extraction of plant water in the laboratory. The reproducibility of this method is similar to the analytical uncertainty in mass spectrometry analyses.
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Affiliation(s)
- Mohammed I El-Shenawy
- Institute for Geology and Mineralogy, University of Cologne, Cologne, Germany
- Department of Geology, Beni-Suef University, Beni-Suef, Egypt
| | - Daniel Herwartz
- Institute for Geology and Mineralogy, University of Cologne, Cologne, Germany
| | - Michael Staubwasser
- Institute for Geology and Mineralogy, University of Cologne, Cologne, Germany
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Song Y, Yan D, Liu T, Lu Y, Jiao R, Wen Y, Qin T, Weng B, Shi W. The suitability of isotopic methods in identifying water sources of a shallow-rooted herbaceous plant in a desert steppe. Sci Total Environ 2023; 902:166072. [PMID: 37544443 DOI: 10.1016/j.scitotenv.2023.166072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 07/19/2023] [Accepted: 08/03/2023] [Indexed: 08/08/2023]
Abstract
Isotopic methodologies have gained prominence in investigating the composition of plant water sources; however, concerns regarding their suitability and reliability in diverse environments have emerged in recent years. This study presents a comparative analysis of root, soil, and liquid water (precipitation, dew, and groundwater) samples obtained from a desert steppe using isotope ratio infrared spectrometry (IRIS) and isotope ratio mass spectrometry (IRMS). The objective was to evaluate the applicability of these techniques in discerning the water sources of Stipa breviflora, a shallow-rooted herbaceous plant species. Additionally, we explored the root water uptake characteristics and water use strategy of S. breviflora. Our findings indicate that the IRIS method had more enriched values of D compared to the IRMS method across all samples, while no discernible pattern was observed for 18O. Notably, the differences observed among all samples exceeded the instruments' accuracies. Moreover, an unexpected occurrence was noted, whereby both D and 18O values in the root water were more enriched than in any of the considered water sources, rendering identification of the plant water sources unattainable. By conducting a re-analysis of more refined soil layer samples, we discovered that S. breviflora exhibits the ability to absorb and utilize water sources in close proximity to the soil surface. It further suggested that the shallow-rooted herbaceous plants in desert steppes can exploit small rainfalls, frequently overlooked in their ecological importance. Considering the distinctive soil and plant characteristics of desert steppes, we recommend adopting IRMS methods in conjunction with refined surface soil sampling for isotopic analysis aiming to identify water sources of shallow-rooted herbaceous plants. This study provides novel insights into assessing the suitability of isotopic techniques for analyzing plant water sources, while enhancing our understanding of water use strategies and environmental adaptation mechanisms employed by shallow-rooted herbaceous plants within xerophytic grassland ecosystems.
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Affiliation(s)
- Yifan Song
- State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing 100038, China; Yinshanbeilu Grassland Eco-hydrology National Observation and Research Station, China Institute of Water Resources and Hydropower Research, Beijing 100038, China; Autonomous Region Collaborative Innovation Center for Integrated Management of Water Resources and Water Environment in the Inner Mongolia Reaches of the Yellow River, Hohhot 010018, China
| | - Denghua Yan
- State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing 100038, China; Yinshanbeilu Grassland Eco-hydrology National Observation and Research Station, China Institute of Water Resources and Hydropower Research, Beijing 100038, China.
| | - Tiejun Liu
- Yinshanbeilu Grassland Eco-hydrology National Observation and Research Station, China Institute of Water Resources and Hydropower Research, Beijing 100038, China; Autonomous Region Collaborative Innovation Center for Integrated Management of Water Resources and Water Environment in the Inner Mongolia Reaches of the Yellow River, Hohhot 010018, China
| | - Yajing Lu
- Beijing Water Science and Technology Institute, Beijing 100048, China
| | - Rui Jiao
- Yinshanbeilu Grassland Eco-hydrology National Observation and Research Station, China Institute of Water Resources and Hydropower Research, Beijing 100038, China
| | - Yunhao Wen
- School of Ecology and Environment, Inner Mongolia University, Hohhot 010020, China
| | - Tianling Qin
- State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing 100038, China; Yinshanbeilu Grassland Eco-hydrology National Observation and Research Station, China Institute of Water Resources and Hydropower Research, Beijing 100038, China
| | - Baisha Weng
- State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing 100038, China; Yinshanbeilu Grassland Eco-hydrology National Observation and Research Station, China Institute of Water Resources and Hydropower Research, Beijing 100038, China
| | - Wei Shi
- School of Ecology and Environment, Inner Mongolia University, Hohhot 010020, China
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Orlowski N, Rinderer M, Dubbert M, Ceperley N, Hrachowitz M, Gessler A, Rothfuss Y, Sprenger M, Heidbüchel I, Kübert A, Beyer M, Zuecco G, McCarter C. Challenges in studying water fluxes within the soil-plant-atmosphere continuum: A tracer-based perspective on pathways to progress. Sci Total Environ 2023; 881:163510. [PMID: 37059146 DOI: 10.1016/j.scitotenv.2023.163510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 04/04/2023] [Accepted: 04/10/2023] [Indexed: 06/01/2023]
Abstract
Tracing and quantifying water fluxes in the hydrological cycle is crucial for understanding the current state of ecohydrological systems and their vulnerability to environmental change. Especially the interface between ecosystems and the atmosphere that is strongly mediated by plants is important to meaningfully describe ecohydrological system functioning. Many of the dynamic interactions generated by water fluxes between soil, plant and the atmosphere are not well understood, which is partly due to a lack of interdisciplinary research. This opinion paper reflects the outcome of a discussion among hydrologists, plant ecophysiologists and soil scientists on open questions and new opportunities for collaborative research on the topic "water fluxes in the soil-plant-atmosphere continuum" especially focusing on environmental and artificial tracers. We emphasize the need for a multi-scale experimental approach, where a hypothesis is tested at multiple spatial scales and under diverse environmental conditions to better describe the small-scale processes (i.e., causes) that lead to large-scale patterns of ecosystem functioning (i.e., consequences). Novel in-situ, high-frequency measurement techniques offer the opportunity to sample data at a high spatial and temporal resolution needed to understand the underlying processes. We advocate for a combination of long-term natural abundance measurements and event-based approaches. Multiple environmental and artificial tracers, such as stable isotopes, and a suite of experimental and analytical approaches should be combined to complement information gained by different methods. Virtual experiments using process-based models should be used to inform sampling campaigns and field experiments, e.g., to improve experimental designs and to simulate experimental outcomes. On the other hand, experimental data are a pre-requisite to improve our currently incomplete models. Interdisciplinary collaboration will help to overcome research gaps that overlap across different earth system science fields and help to generate a more holistic view of water fluxes between soil, plant and atmosphere in diverse ecosystems.
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Affiliation(s)
- Natalie Orlowski
- Hydrology, Faculty of Environment and Natural Resources, University of Freiburg, Freiburg im Breisgau, Germany.
| | - Michael Rinderer
- Hydrology, Faculty of Environment and Natural Resources, University of Freiburg, Freiburg im Breisgau, Germany; Geo7 AG, Bern, Switzerland
| | - Maren Dubbert
- Isotope Biogeochemistry and Gasfluxes, ZALF, Müncheberg, Germany
| | | | - Markus Hrachowitz
- Department of Water Management, Faculty of Civil Engineering and Geosciences, Delft University of Technology, Stevinweg 1, 2628CN Delft, Netherlands
| | - Arthur Gessler
- Forest Dynamics, Swiss Federal Research Institute WSL, Birmensdorf, Switzerland; Institute of Terrestrial Ecosystems, ETH Zurich, Zurich, Switzerland
| | - Youri Rothfuss
- Institute of Bio- and Geosciences, Agrosphere (IBG-3), Forschungszentrum Jülich GmbH, Jülich, Germany; Terra Teaching and Research Centre, University of Liège, Gembloux, Belgium
| | - Matthias Sprenger
- Earth and Environmental Sciences at the Lawrence Berkeley National Laboratory, Berkeley, USA
| | - Ingo Heidbüchel
- Hydrological Modelling, University of Bayreuth, Bayreuth, Germany; Hydrogeology, Helmholtz Centre for Environmental Research - UFZ, Leipzig, Germany
| | - Angelika Kübert
- Institute for Atmospheric and Earth System Research (INAR), University of Helsinki, Helsinki, Finland
| | - Matthias Beyer
- Institute for Geoecology, Technische Universität Braunschweig, Braunschweig, Germany
| | - Giulia Zuecco
- Department of Land, Environment, Agriculture and Forestry, University of Padova, Legnaro, Italy; Department of Chemical Sciences, University of Padova, Padova, Italy
| | - Colin McCarter
- Department of Geography, Department of Biology and Chemistry, Nipissing University, North Bay, Ontario, Canada
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Zhang J, Xu Z. Vacuum extraction of high-salinity water for the determination of oxygen and hydrogen isotopic compositions using cavity ring-down spectroscopy. Microchem J 2023. [DOI: 10.1016/j.microc.2023.108678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2023]
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Behzad HM, Arif M, Duan S, Kavousi A, Cao M, Liu J, Jiang Y. Seasonal variations in water uptake and transpiration for plants in a karst critical zone in China. Sci Total Environ 2023; 860:160424. [PMID: 36436637 DOI: 10.1016/j.scitotenv.2022.160424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 11/13/2022] [Accepted: 11/19/2022] [Indexed: 06/16/2023]
Abstract
Despite substantial drought conditions in the karst critical zone (KCZ), the KCZ landscapes are often covered with forest woody plants. However, it is not well understood how these plants balance water supply and demand to survive in such a water-limited environment. This study investigated the water uptake and transpiration relationships of four coexisting woody species in a subtropical karst forest ecosystem using measurements of microclimate, soil moisture, stable isotopes (δ18O, δ2H, and δ13C), intrinsic water-use efficiency (WUEi), sap flow, and rooting depth. The focus was on identifying differences within- and between-species across soil- and rock-dominated habitats (SDH and RDH) during the rainy growing season (September 2017) and dry season (February 2018). Species across both habitats tended to have higher transpiration with lower WUEi during the rainy season and lower transpiration with higher WUEi during the dry season. Compared to those in the SDH, species in the RDH showed lower transpiration with higher WUEi in both seasons. The dominant water sources were soil water and rainwater for supporting rainy-season transpiration in the SDH and RDH, respectively, and groundwater was the main water source for supporting dry-season transpiration in both habitats. A clear ecohydrological niche differentiation was also revealed among species. Across both habitats, shallower-rooted species with higher soil-water uptake, compared to deeper-rooted species with higher groundwater uptake, showed higher transpiration and lower WUEi during the rainy season and vice versa during the dry season. This study provides integrated insights into how forest woody plants in the KCZ regulate transpiration and WUEi in response to drought stress through interactions with seasonal water sources in the environment.
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Affiliation(s)
- Hamid M Behzad
- Chongqing Key Laboratory of Karst Environment & School of Geographical Sciences, Southwest University, Chongqing 400715, China
| | - Muhammad Arif
- Key Laboratory of Eco-Environments in the Three Gorges Reservoir Region (Ministry of Education), Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, School of Life Sciences, Southwest University, Chongqing 400715, China; Biological Science Research Center, Academy for Advanced Interdisciplinary Studies, Southwest University, Chongqing 400715, China
| | - Shihui Duan
- Chongqing Key Laboratory of Karst Environment & School of Geographical Sciences, Southwest University, Chongqing 400715, China
| | - Alireza Kavousi
- Institute of Groundwater Management, Technische Universität Dresden, 01069 Dresden, Germany
| | - Min Cao
- Chongqing Key Laboratory of Karst Environment & School of Geographical Sciences, Southwest University, Chongqing 400715, China; School of Earth Sciences, Yunnan University, 650500, China
| | - Jiuchan Liu
- Chongqing Key Laboratory of Karst Environment & School of Geographical Sciences, Southwest University, Chongqing 400715, China
| | - Yongjun Jiang
- Chongqing Key Laboratory of Karst Environment & School of Geographical Sciences, Southwest University, Chongqing 400715, China.
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Kühnhammer K, Dahlmann A, Iraheta A, Gerchow M, Birkel C, Marshall JD, Beyer M. Continuous in situ measurements of water stable isotopes in soils, tree trunk and root xylem: Field approval. Rapid Commun Mass Spectrom 2022; 36:e9232. [PMID: 34862674 DOI: 10.1002/rcm.9232] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 11/26/2021] [Accepted: 11/27/2021] [Indexed: 06/13/2023]
Abstract
RATIONALE New methods to measure stable isotopes of soil and tree water directly in the field enable us to increase the temporal resolution of obtained data and advance our knowledge on the dynamics of soil and plant water fluxes. Only few field applications exist. However, these are needed to further improve novel methods and hence exploit their full potential. METHODS We tested the borehole equilibration method in the field and collected in situ and destructive samples of stable isotopes of soil, trunk and root xylem water over a 2.5-month experiment in a tropical dry forest under natural abundance conditions and following labelled irrigation. Water from destructive samples was extracted using cryogenic vacuum extraction. Isotope ratios were determined with IRIS instruments using cavity ring-down spectroscopy both in the field and in the laboratory. RESULTS In general, timelines of both methods agreed well for both soil and xylem samples. Irrigation labelled with heavy hydrogen isotopes clearly impacted the isotope composition of soil water and one of the two studied tree species. Inter-method deviations increased in consequence of labelling, which revealed their different capabilities to cover spatial and temporal heterogeneities. CONCLUSIONS We applied the novel borehole equilibration method in a remote field location. Our experiment reinforced the potential of this in situ method for measuring xylem water isotopes in both tree trunks and roots and confirmed the reliability of gas permeable soil probes. However, in situ xylem measurements should be further developed to reduce the uncertainty within the range of natural abundance and hence enable their full potential.
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Affiliation(s)
- Kathrin Kühnhammer
- IGOE, Environmental Geochemistry, Braunschweig, Germany
- Ecosystem Physiology, University of Freiburg, Freiburg, Germany
| | - Adrian Dahlmann
- IGOE, Environmental Geochemistry, Braunschweig, Germany
- Ecosystem Physiology, University of Freiburg, Freiburg, Germany
| | | | | | - Christian Birkel
- Department of Geography and Water and Global Change Observatory, Universidad de Costa Rica (UCR), San José, Costa Rica
| | - John D Marshall
- Department of Forest Ecology and Management, Faculty of Forest Sciences, Swedish University of Agricultural Sciences, Umeå, Sweden
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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. New Phytol 2022; 233:194-206. [PMID: 34610146 PMCID: PMC9293437 DOI: 10.1111/nph.17767] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [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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Losso A, Bär A, Unterholzner L, Bahn M, Mayr S. Branch water uptake and redistribution in two conifers at the alpine treeline. Sci Rep 2021; 11:22560. [PMID: 34799592 PMCID: PMC8604952 DOI: 10.1038/s41598-021-00436-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 10/05/2021] [Indexed: 11/21/2022] Open
Abstract
During winter, conifers at the alpine treeline suffer dramatic losses of hydraulic conductivity, which are successfully recovered during late winter. Previous studies indicated branch water uptake to support hydraulic recovery. We analyzed water absorption and redistribution in Picea abies and Larix decidua growing at the treeline by in situ exposure of branches to δ2H-labelled water. Both species suffered high winter embolism rates (> 40-60% loss of conductivity) and recovered in late winter (< 20%). Isotopic analysis showed water to be absorbed over branches and redistributed within the crown during late winter. Labelled water was redistributed over 425 ± 5 cm within the axes system and shifted to the trunk, lower and higher branches (tree height 330 ± 40 cm). This demonstrated relevant branch water uptake and re-distribution in treeline conifers. The extent of water absorption and re-distribution was species-specific, with L. decidua showing higher rates. In natura, melting snow might be the prime source for absorbed and redistributed water, enabling embolism repair and restoration of water reservoirs prior to the vegetation period. Pronounced water uptake in the deciduous L. decidua indicated bark to participate in the process of water absorption.
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Affiliation(s)
- Adriano Losso
- Department of Botany, University of Innsbruck, Sternwartestraße 15, 6020, Innsbruck, Austria.
- Hawkesbury Institute for the Environment, Western Sydney University, Richmond, NSW, 2753, Australia.
| | - Andreas Bär
- Department of Botany, University of Innsbruck, Sternwartestraße 15, 6020, Innsbruck, Austria
| | | | - Michael Bahn
- Department of Ecology, University of Innsbruck, Sternwartestraße 15, 6020, Innsbruck, Austria
| | - Stefan Mayr
- Department of Botany, University of Innsbruck, Sternwartestraße 15, 6020, Innsbruck, Austria
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Millar C, Janzen K, Nehemy MF, Koehler G, Hervé-Fernández P, McDonnell JJ. Organic contamination detection for isotopic analysis of water by laser spectroscopy. Rapid Commun Mass Spectrom 2021; 35:e9118. [PMID: 33939862 DOI: 10.1002/rcm.9118] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 04/30/2021] [Accepted: 05/01/2021] [Indexed: 06/12/2023]
Abstract
RATIONALE Hydrogen and oxygen stable isotope ratios (δ2 H, δ17 O, and δ18 O values) are commonly used tracers of water. These ratios can be measured by isotope ratio infrared spectroscopy (IRIS). However, IRIS approaches are prone to errors induced by organic compounds present in plant, soil, and natural water samples. A novel approach using 17 O-excess values has shown promise for flagging spectrally contaminated plant samples during IRIS analysis. A systematic assessment of this flagging system is needed to prove it useful. METHODS Errors induced by methanol and ethanol water mixtures on measured IRIS and isotope ratio mass spectrometry (IRMS) results were evaluated. For IRIS analyses both liquid- and vapour-mode (via direct vapour equilibration) methods are used. The δ2 H, δ17 O, and δ18 O values were measured and compared with known reference values to determine the errors induced by methanol and ethanol contamination. In addition, the 17 O-excess contamination detection approach was tested. This is a post-processing detection tool for both liquid and vapour IRIS triple-isotope analyses, utilizing calculated 17 O-excess values to flag contaminated samples. RESULTS Organic contamination induced significant errors in IRIS results, not seen in IRMS results. Methanol caused larger errors than ethanol. Results from vapour-IRIS analyses had larger errors than those from liquid-IRIS analyses. The 17 O-excess approach identified methanol driven error in liquid- and vapour-mode IRIS samples at levels where isotope results became unacceptably erroneous. For ethanol contaminated samples, a mix of erroneous and correct flagging occurred with the 17 O-excess method. Our results indicate that methanol is the more problematic contaminant for data corruption. The 17 O-excess method was therefore useful for data quality control. CONCLUSIONS Organic contamination caused significant errors in IRIS stable isotope results. These errors were larger during vapour analyses than during liquid IRIS analyses, and larger for methanol than ethanol contamination. The 17 O-excess method is highly sensitive for detecting narrowband (methanol) contamination error in vapour and liquid analysis modes in IRIS.
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Affiliation(s)
- Cody Millar
- Global Institute for Water Security, School of Environment and Sustainability, University of Saskatchewan, 11 Innovation Boulevard, Saskatoon, SK, S7N 3H5, Canada
| | - Kim Janzen
- Global Institute for Water Security, School of Environment and Sustainability, University of Saskatchewan, 11 Innovation Boulevard, Saskatoon, SK, S7N 3H5, Canada
| | - Magali F Nehemy
- Global Institute for Water Security, School of Environment and Sustainability, University of Saskatchewan, 11 Innovation Boulevard, Saskatoon, SK, S7N 3H5, Canada
| | - Geoff Koehler
- NHRC Stable Isotope Laboratory, Environment and Climate Change Canada, 11 Innovation Boulevard, Saskatoon, SK, S7N 3H5, Canada
| | - Pedro Hervé-Fernández
- Global Institute for Water Security, School of Environment and Sustainability, University of Saskatchewan, 11 Innovation Boulevard, Saskatoon, SK, S7N 3H5, Canada
- Instituto de la Patagonia, Departamento de Hidrobiología, Universidad de Magallanes, Punta Arenas, Chile
- Facultad de Ciencias Liberales, Universidad Adolfo Ibañez, Viña del Mar, Chile
| | - Jeffrey J McDonnell
- Global Institute for Water Security, School of Environment and Sustainability, University of Saskatchewan, 11 Innovation Boulevard, Saskatoon, SK, S7N 3H5, Canada
- School of Geography, Earth & Environmental Sciences, University of Birmingham, Birmingham, UK
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11
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Cui J, Lide T, Yu W. Organic contamination in online laser-based plant stem and leaf water isotope measurements for pre-extracted samples. Isotopes Environ Health Stud 2021; 57:262-270. [PMID: 33594914 DOI: 10.1080/10256016.2021.1883010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 12/17/2020] [Indexed: 06/12/2023]
Abstract
Water stable isotopes have been widely used as natural tracers to investigate soil-plant-atmosphere interactions. Recent developments in induction module cavity ring-down spectroscopy (IM-CRDS) have made it possible to rapidly complete isotope analyses, and to combust co-extracted organic compounds at the same time. However, the agreement between IM-CRDS and isotope ratio mass spectrometry (IRMS) analyses has generally been poor and was primarily attributable to spectral interference of IM-CRDS. Here we evaluated the impacts of organic contamination on the isotope ratios using IM-CRDS with two different methods. No spectral interference was observed for solid samples measured directly by IM-CRDS, whereas clear organic contamination occurred in isotope analyses for pre-extracted plant stem and leaf samples. Our results demonstrate that IM-CRDS can fully combust co-extracted organic compounds by in-line oxidation in the direct measurement of solid samples, although this may not guarantee that the IM-CRDS can obtain better isotopic data than IRMS. It may be risky to evaluate the performance of IM-CRDS by measuring pre-extracted water samples because cryogenic vacuum distillation is likely to introduce extra organic compounds, which may not be fully removed during subsequent IM-CRDS measurement. In addition, spectral variables are useful for post-processing corrections.
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Affiliation(s)
- Jiangpeng Cui
- Key Laboratory of Tibetan Plateau Environment Change and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, People's Republic of China
- Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing, People's Republic of China
| | - Tian Lide
- Key Laboratory of Tibetan Plateau Environment Change and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, People's Republic of China
- CAS Centre for Excellence in Tibetan Plateau Earth Sciences, Beijing, People's Republic of China
- Institute of International Rivers and Eco-Security, Yunnan University, Kunming, People's Republic of China
| | - Wusheng Yu
- Key Laboratory of Tibetan Plateau Environment Change and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, People's Republic of China
- CAS Centre for Excellence in Tibetan Plateau Earth Sciences, Beijing, People's Republic of China
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12
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Foote DM, Berkelhammer M, Marone J, Horswill CA. Combining Anthropometry and Bioelectrical Impedance to Predict Body Fat in Female Athletes. J Athl Train 2021; 57:393-401. [PMID: 34038948 DOI: 10.4085/1062-6050-0747.20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
CONTEXT Accurate methods for predicting percent body fat in female athletes are needed for those who lose weight for competition. Methods mandated by sports-governing bodies for minimal weight determination in such athletes lack validation. OBJECTIVE To determine whether combining anthropometry (skinfolds, SF) and bioelectrical impedance analysis (BIA) in a 3 component model (3C) would improve the prediction of percentage body fat (%Fat) in female athletes. Secondarily, the Slaughter skinfold equation was evaluated. We hypothesized that compared to outcomes for SF or BIA alone, 3C-determined %Fat would not differ from our criterion method (accuracy) and would be a stronger predictor (higher r2) of the criterion. DESIGN Cross sectional. SETTING Laboratory-based study during the pre-season for collegiate sport. PARTICIPANTS Female athletes (n=18 D1 NCAA) recruited from swim and gymnastic teams. MAIN OUTCOME VARIABLES %Fat based on a four-compartment (4C) criterion incorporating body density (air displacement plethysmography), total body water (D2O dilution), and bone mineral mass (DEXA) compared to predicted %Fat using SF alone (Slaughter equation), bioelectrical impedance analysis (single frequency for TBW estimate) and combined skinfolds and BIA (3C). RESULTS Regression revealed that for %Fat using the criterion 4C, the highest adjusted coefficient of determination and lowest prediction error (r2 ±standard error of estimate) was 3C (r2=0.87 ±2.8%) followed by BIA (r2=0.80 ±3.5%) and SF (r2=0.76 ± 3.8%) (for all, p<0.05). Means differed for %Fat determined using BIA (26.6 ±7.5) and 3C (25.5 ±7.2) vs. the 4C (23.5 ±7.4) (ANOVA and post hoc p<0.05). The SF estimate (24.0 +7.8) did not differ from the 4C value. CONCLUSIONS Combining SF and BIA might improve the prediction and lower the prediction error for determining %Fat in female athletes compared to SF or BIA separately. Regardless, the Slaughter skinfold equation appeared accurate for determining the mean %Fat in these female athletes.
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Affiliation(s)
| | | | - Jane Marone
- 3Department of Kinesiology & Nutrition, University of Illinois at Chicago; and
| | - Craig A Horswill
- 3Department of Kinesiology & Nutrition, University of Illinois at Chicago; and
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13
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de Graaf S, Vonhof HB, Levy EJ, Markowska M, Haug GH. Isotope ratio infrared spectroscopy analysis of water samples without memory effects. Rapid Commun Mass Spectrom 2021; 35:e9055. [PMID: 33521977 DOI: 10.1002/rcm.9055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Revised: 01/21/2021] [Accepted: 01/22/2021] [Indexed: 06/12/2023]
Abstract
RATIONALE Since their introduction more than a decade ago, isotope ratio infrared spectroscopy (IRIS) systems have rapidly become the standard for oxygen (δ18 O) and hydrogen (δ2 H) isotope analysis of water samples. An important disadvantage of IRIS systems is the well-documented sample-to-sample memory effect, which requires each sample to be analyzed multiple times before the desired accuracy is reached, lengthening analysis times and driving up the costs of analyses. METHODS We present an adapted set-up and calculation protocol for fully automated analysis of water samples using a Picarro L2140-i cavity ring-down spectroscopy instrument. The adaptation removes memory effects by use of a continuously moisturized nitrogen carrier gas. Water samples of 0.5 μL are measured on top of the water vapor background, after which isotope ratios are calculated by subtraction of the background from the sample peaks. RESULTS With this new technique, single injections of water samples have internal precisions (1σ) below 0.05‰ for δ18 O values and 0.1‰ for δ2 H values, regardless of the isotope ratio of the previous sample. Precision is worse, however, when the isotope difference between the sample and background water is too large (i.e., exceeding approximately 9‰ for δ18 O values and 70‰ for δ2 H values). Isotope ratios show negligible drift across the four weeks within which the experiments were performed. The single-injection 1σ precision for 17 O excess (Δ'17 O) determined with this method is 60 per meg. CONCLUSIONS Our experiments demonstrate that by removing sample-to-sample memory effects with a moisturized carrier gas, the time for measurement of δ18 O and δ2 H values using an IRIS system can be reduced markedly without compromising the analytical precision and accuracy. Thorough replication is needed to achieve sufficiently low uncertainties for Δ'17 O.
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Affiliation(s)
- Stefan de Graaf
- Climate Geochemistry Department, Max Planck Institute for Chemistry, Mainz, Germany
| | - Hubert B Vonhof
- Climate Geochemistry Department, Max Planck Institute for Chemistry, Mainz, Germany
| | - Elan J Levy
- Climate Geochemistry Department, Max Planck Institute for Chemistry, Mainz, Germany
| | - Monika Markowska
- Climate Geochemistry Department, Max Planck Institute for Chemistry, Mainz, Germany
| | - Gerald H Haug
- Climate Geochemistry Department, Max Planck Institute for Chemistry, Mainz, Germany
- Department of Earth Sciences, ETH Zürich, Sonneggstrasse 5, Zürich, 8092, Switzerland
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14
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Wang X, Jansen HG, Duin H, Meijer HAJ. Measurement of δ18O and δ2H of water and ethanol in wine by Off-Axis Integrated Cavity Output Spectroscopy and Isotope Ratio Mass Spectrometry. Eur Food Res Technol 2021; 247:1899-912. [DOI: 10.1007/s00217-021-03758-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
AbstractThere are two officially approved methods for stable isotope analysis for wine authentication. One describes δ18O measurements of the wine water using Isotope Ratio Mass Spectrometry (IRMS), and the other one uses Deuterium-Nuclear Magnetic Resonance (2H-NMR) to measure the deuterium of the wine ethanol. Recently, off-axis integrated cavity output (laser) spectroscopy (OA-ICOS) has become an easier alternative to quantify wine water isotopes, thanks to the spectral contaminant identifier (SCI). We utilized an OA-ICOS analyser with SCI to measure the δ18O and δ2H of water in 27 wine samples without any pre-treatment. The OA-ICOS results reveal a wealth of information about the growth conditions of the wines, which shows the advantages to extend the official δ18O wine water method by δ2H that is obtained easily from OA-ICOS. We also performed high-temperature pyrolysis and chromium reduction combined with IRMS measurements to illustrate the “whole wine” isotope ratios. The δ18O results of OA-ICOS and IRMS show non-significant differences, but the δ2H results of both methods differ much more. As the δ2H difference between these two methods is mainly caused by ethanol, we investigated the possibility to deduce deuterium of wine ethanol from this difference. The results present large uncertainties and deviate from the obtained 2H-NMR results. The deviation is caused by the other constituents in the wine, and the uncertainty is due to the limited precision of the SCI-based correction, which need to improve to obtain the 2H values of ethanol as alternative for the 2H-NMR method.
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15
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Song X, Chen Y, Helliker BR, Tang X, Li F, Zhou Y. Reply to Evaristo et al.: Strong evidence for the need of correcting extraction bias in an early study of ecohydrological separation. Proc Natl Acad Sci U S A 2021; 118:e2103604118. [PMID: 33850051 DOI: 10.1073/pnas.2103604118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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16
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Hafner BD, Hesse BD, Grams TEE. Friendly neighbours: Hydraulic redistribution accounts for one quarter of water used by neighbouring drought stressed tree saplings. Plant Cell Environ 2021; 44:1243-1256. [PMID: 32683699 DOI: 10.1111/pce.13852] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 07/06/2020] [Accepted: 07/10/2020] [Indexed: 06/11/2023]
Abstract
Hydraulic redistribution (HR) can buffer drought events of tree individuals, however, its relevance for neighbouring trees remains unclear. Here, we quantified HR to neighbouring trees in single- and mixed-species combinations. We hypothesized that uptake of HR water positively correlates with root length, number of root tips and root xylem hydraulic conductivity and that neighbours in single-species combinations receive more HR water than in phylogenetic distant mixed-species combinations. In a split-root experiment, a sapling with its roots split between two pots redistributed deuterium labelled water from a moist to a dry pot with an additional tree each. We quantified HR water received by the sapling in the dry pot for six temperate tree species. After 7 days, one quarter of the water in roots (2.1 ± 0.4 ml), stems (0.8 ± 0.2 ml) and transpiration (1.0 ± 0.3 ml) of the drought stressed sapling originated from HR. The amount of HR water transpired by the receiving plant stayed constant throughout the experiment. While the uptake of HR water increased with root length, species identity did not affect HR as saplings of Picea abies ((L.) Karst) and Fagus sylvatica (L.) in single- and mixed-species combinations received the same amount of HR water.
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Affiliation(s)
- Benjamin D Hafner
- Ecophysiology of Plants, Technical University of Munich, Freising, Germany
- School of Integrated Plant Science, Cornell University, New York, New York, USA
| | - Benjamin D Hesse
- Ecophysiology of Plants, Technical University of Munich, Freising, Germany
| | - Thorsten E E Grams
- Ecophysiology of Plants, Technical University of Munich, Freising, Germany
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17
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Jez JM, Topp CN, Mcnicol G, Yu Z, Berry ZC, Emery N, Soper FM, Yang WH. Tracing plant–environment interactions from organismal to planetary scales using stable isotopes: a mini review. Emerg Top Life Sci 2021; 5:301-16. [DOI: 10.1042/etls20200277] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2020] [Revised: 01/28/2021] [Accepted: 01/29/2021] [Indexed: 01/09/2023]
Abstract
Natural isotope variation forms a mosaic of isotopically distinct pools across the biosphere and flows between pools integrate plant ecology with global biogeochemical cycling. Carbon, nitrogen, and water isotopic ratios (among others) can be measured in plant tissues, at root and foliar interfaces, and in adjacent atmospheric, water, and soil environments. Natural abundance isotopes provide ecological insight to complement and enhance biogeochemical research, such as understanding the physiological conditions during photosynthetic assimilation (e.g. water stress) or the contribution of unusual plant water or nutrient sources (e.g. fog, foliar deposition). While foundational concepts and methods have endured through four decades of research, technological improvements that enable measurement at fine spatiotemporal scales, of multiple isotopes, and of isotopomers, are advancing the field of stable isotope ecology. For example, isotope studies now benefit from the maturation of field-portable infrared spectroscopy, which allows the exploration of plant–environment sensitivity at physiological timescales. Isotope ecology is also benefiting from, and contributing to, new understanding of the plant–soil–atmosphere system, such as improving the representation of soil carbon pools and turnover in land surface models. At larger Earth-system scales, a maturing global coverage of isotope data and new data from site networks offer exciting synthesis opportunities to merge the insights of single-or multi-isotope analysis with ecosystem and remote sensing data in a data-driven modeling framework, to create geospatial isotope products essential for studies of global environmental change.
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18
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Juhlke TR, Van Geldern R, Barth JAC, Bendix J, Bräuning A, Garel E, Häusser M, Huneau F, Knerr I, Santoni S, Szymczak S, Trachte K. Temporal offset between precipitation and water uptake of Mediterranean pine trees varies with elevation and season. Sci Total Environ 2021; 755:142539. [PMID: 33045601 DOI: 10.1016/j.scitotenv.2020.142539] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 09/18/2020] [Accepted: 09/18/2020] [Indexed: 06/11/2023]
Abstract
For climate models that use paleo-environment data to predict future climate change, tree-ring isotope variations are one important archive for the reconstruction of paleo-hydrological conditions. Due to the rather complicated pathway of water, starting from precipitation until its uptake by trees and the final incorporation of its components into tree-ring cellulose, a closer inspection of seasonal variations of tree water uptake is important. In this study, branch and needle samples of two pine species (Pinus pinaster and Pinus nigra subsp. laricio) and several water compartments (precipitation, creek, soil) were sampled over a two-year period and analyzed for the temporal variations of their oxygen and hydrogen stable isotope ratios (δ18O and δ2H) at five sites over an elevation gradient from sea level to around 1600 m a.s.l. on the Mediterranean island of Corsica (France). A new model was established to disentangle temporal relationships of source water uptake of trees. It uses a calculation method that incorporates the two processes mostly expected to affect source water composition: mixing of waters and evaporation. The model results showed that the temporal offset from precipitation to water uptake is not constant and varies with elevation and season. Overall, seasonal source water origin was shown to be dominated by precipitation from autumn and spring. While autumn precipitation was a more important water source for trees growing at mid- (~800-1000 m a.s.l) and high-elevation (~1600 m a.s.l.) sites, trees at coastal sites mostly took up water from late winter and spring. These findings show that predicted decreases in precipitation amounts during the wet season in the Mediterranean can have strong impacts on water availability for pine trees, especially at higher elevations.
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Affiliation(s)
- T R Juhlke
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Department Geographie und Geowissenschaften, GeoZentrum Nordbayern, Schlossgarten 5, 91054 Erlangen, Germany.
| | - R Van Geldern
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Department Geographie und Geowissenschaften, GeoZentrum Nordbayern, Schlossgarten 5, 91054 Erlangen, Germany
| | - J A C Barth
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Department Geographie und Geowissenschaften, GeoZentrum Nordbayern, Schlossgarten 5, 91054 Erlangen, Germany
| | - J Bendix
- Philipps University of Marburg, Faculty of Geography, Laboratory for Climatology and Remote Sensing, Deutschhausstr. 12, 35032 Marburg, Germany
| | - A Bräuning
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Department Geographie und Geowissenschaften, Institut für Geographie, Wetterkreuz 15, 91058 Erlangen, Germany
| | - E Garel
- Université de Corse Pascal Paoli, Faculté des Sciences et Techniques, Laboratoire d'Hydrogéologie, Campus Grimaldi, BP 52, F-20250 Corte, France; CNRS, UMR 6134 SPE, F-20250 Corte, France
| | - M Häusser
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Department Geographie und Geowissenschaften, Institut für Geographie, Wetterkreuz 15, 91058 Erlangen, Germany
| | - F Huneau
- Université de Corse Pascal Paoli, Faculté des Sciences et Techniques, Laboratoire d'Hydrogéologie, Campus Grimaldi, BP 52, F-20250 Corte, France; CNRS, UMR 6134 SPE, F-20250 Corte, France
| | - I Knerr
- Philipps University of Marburg, Faculty of Geography, Laboratory for Climatology and Remote Sensing, Deutschhausstr. 12, 35032 Marburg, Germany
| | - S Santoni
- Université de Corse Pascal Paoli, Faculté des Sciences et Techniques, Laboratoire d'Hydrogéologie, Campus Grimaldi, BP 52, F-20250 Corte, France; CNRS, UMR 6134 SPE, F-20250 Corte, France
| | - S Szymczak
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Department Geographie und Geowissenschaften, Institut für Geographie, Wetterkreuz 15, 91058 Erlangen, Germany
| | - K Trachte
- Brandenburg University of Technology (BTU), Institute for Environmental Sciences, 03044 Cottbus-Senftenberg, Germany
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Anparasan L, Hobson KA. Tracing sources of carbon and hydrogen to stored lipids in migratory passerines using stable isotope (δ 13C, δ 2H) measurements. Oecologia 2021; 195:37-49. [PMID: 33389017 DOI: 10.1007/s00442-020-04827-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Accepted: 12/09/2020] [Indexed: 11/29/2022]
Abstract
Using measurements of naturally occurring stable isotopes in feathers to determine avian origin and migratory patterns is well established. However, isotopically determining nutritional origins of lipids, a major migratory fuel, has not been attempted. This study explores isotopic links between diet and stored lipids in captive white-throated sparrows (Zonotrichia albicollis) by providing isotopically distinct mixtures of carbohydrates/oils and drinking water and assessing the δ13C and δ2H values of stored lipid, breath CO2 (δ13C) and breath water vapour (δ2H). Stored lipid δ13C and δ2H values correlated with the isotopic values found in dietary carbohydrates/oils and drinking water treatments, respectively, indicating a clear traceable transfer of environmental dietary isotopic signals into body lipids. Dietary oils and carbohydrates contributed 80-82% of carbon and 44-46% of hydrogen, respectively, to stored lipids. Drinking water contributed 18-28% of hydrogen to stored lipids. Isotopic relationships were quantifiable using linear calibration algorithms which provide the basis for the construction of tissue isoscapes for migratory passerines. Breath CO2 δ13C values and breath water vapour δ2H values for fed and fasted birds reflected dietary sources. Breath CO2 δ13C values were higher for fasted birds than for fed birds by an average of 4.5‰ while breath water vapour δ2H values were lower for fasted birds by an average of 48.9‰. These results indicate that lipids and metabolites from their subsequent breakdown for fuel isotopically reflect dietary sources but complicate interpretation of such data, especially for wild migrating birds. Applications and limitations of these findings to the creation of "liposcapes" are examined.
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Affiliation(s)
- Libesha Anparasan
- Department of Biology, University of Western Ontario, 1151 Richmond St, London, ON, N6A 3K7, Canada.
| | - Keith A Hobson
- Department of Biology, University of Western Ontario, 1151 Richmond St, London, ON, N6A 3K7, Canada.,Environment and Climate Change Canada, Saskatoon, SK, S7N 3H5, Canada
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Drake JE, Harwood R, Vårhammar A, Barbour MM, Reich PB, Barton CVM, Tjoelker MG. No evidence of homeostatic regulation of leaf temperature in Eucalyptus parramattensis trees: integration of CO 2 flux and oxygen isotope methodologies. New Phytol 2020; 228:1511-1523. [PMID: 32531796 DOI: 10.1111/nph.16733] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 05/22/2020] [Indexed: 06/11/2023]
Abstract
Thermoregulation of leaf temperature (Tleaf ) may foster metabolic homeostasis in plants, but the degree to which Tleaf is moderated, and under what environmental contexts, is a topic of debate. Isotopic studies inferred the temperature of photosynthetic carbon assimilation to be a constant value of c. 20°C; by contrast, leaf biophysical theory suggests a strong dependence of Tleaf on environmental drivers. Can this apparent disparity be reconciled? We continuously measured Tleaf and whole-crown net CO2 uptake for Eucalyptus parramattensis trees growing in field conditions in whole-tree chambers under ambient and +3°C warming conditions, and calculated assimilation-weighted leaf temperature (TL-AW ) across 265 d, varying in air temperature (Tair ) from -1 to 45°C. We compared these data to TL-AW derived from wood cellulose δ18 O. Tleaf exhibited substantial variation driven by Tair , light intensity, and vapor pressure deficit, and Tleaf was strongly linearly correlated with Tair with a slope of c. 1.0. TL-AW values calculated from cellulose δ18 O vs crown fluxes were remarkably consistent; both varied seasonally and in response to the warming treatment, tracking variation in Tair . The leaves studied here were nearly poikilothermic, with no evidence of thermoregulation of Tleaf towards a homeostatic value. Importantly, this work supports the use of cellulose δ18 O to infer TL-AW , but does not support the concept of strong homeothermic regulation of Tleaf.
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Affiliation(s)
- John E Drake
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW, 2751, Australia
- Sustainable Resources Management, SUNY-ESF, 1 Forestry Drive, Syracuse, NY, 13210, USA
| | - Richard Harwood
- School of Life and Environmental Sciences, The University of Sydney, Private Bag 4011, Narellan, NSW, 2567, Australia
| | - Angelica Vårhammar
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW, 2751, Australia
| | - Margaret M Barbour
- School of Life and Environmental Sciences, The University of Sydney, Private Bag 4011, Narellan, NSW, 2567, Australia
| | - Peter B Reich
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW, 2751, Australia
- Department of Forest Resources, University of Minnesota, 1530 Cleveland Ave N., St Paul, MN, 55108, USA
| | - Craig V M Barton
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW, 2751, Australia
| | - Mark G Tjoelker
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW, 2751, Australia
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21
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de Graaf S, Vonhof HB, Weissbach T, Wassenburg JA, Levy EJ, Kluge T, Haug GH. A comparison of isotope ratio mass spectrometry and cavity ring-down spectroscopy techniques for isotope analysis of fluid inclusion water. Rapid Commun Mass Spectrom 2020; 34:e8837. [PMID: 32424983 DOI: 10.1002/rcm.8837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2020] [Revised: 05/12/2020] [Accepted: 05/14/2020] [Indexed: 06/11/2023]
Abstract
RATIONALE Online oxygen (δ18 O) and hydrogen (δ2 H) isotope analysis of fluid inclusion water entrapped in minerals is widely applied in paleo-fluid studies. In the state of the art of fluid inclusion isotope research, however, there is a scarcity of reported inter-technique comparisons to account for possible analytical offsets. Along with improving analytical precisions and sample size limitations, interlaboratory comparisons can lead to a more robust application of fluid inclusion isotope records. METHODS Mineral samples-including speleothem, travertine, and vein material-were analyzed on two newly setup systems for fluid inclusion isotope analysis to provide an inter-platform comparison. One setup uses a crusher unit connected online to a continuous-flow pyrolysis furnace and an isotope ratio mass spectrometry (IRMS) instrument. In the other setup, a crusher unit is lined up with a cavity ring-down spectroscopy (CRDS) system, and water samples are analyzed on a continuous standard water background to achieve precisions on water injections better than 0.1‰ for δ18 O values and 0.4‰ for δ2 H values for amounts down to 0.2 μL. RESULTS Fluid inclusion isotope analyses on the IRMS setup have an average 1σ reproducibility of 0.4‰ and 2.0‰ for δ18 O and δ2 H values, respectively. The CRDS setup has a better 1σ reproducibility (0.3‰ for δ18 O values and 1.1‰ for δ2 H values) and also a more rapid sample throughput (<30 min per sample). Fluid inclusion isotope analyses are reproducible at these uncertainties for water amounts down to 0.1 μL on both setups. Fluid inclusion isotope data show no systematic offsets between the setups. CONCLUSIONS The close match in fluid inclusion isotope results between the two setups demonstrates the high accuracy of the presented continuous-flow techniques for fluid inclusion isotope analysis. Ideally, experiments such as the one presented in this study will lead to further interlaboratory comparison efforts and the selection of suitable reference materials for fluid inclusion isotopes studies.
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Affiliation(s)
- Stefan de Graaf
- Climate Geochemistry Department, Max Planck Institute for Chemistry, Mainz, Germany
| | - Hubert B Vonhof
- Climate Geochemistry Department, Max Planck Institute for Chemistry, Mainz, Germany
| | - Therese Weissbach
- Ruprecht-Karls University Heidelberg, Institute of Environmental Physics, Heidelberg, Germany
| | - Jasper A Wassenburg
- Climate Geochemistry Department, Max Planck Institute for Chemistry, Mainz, Germany
| | - Elan J Levy
- Climate Geochemistry Department, Max Planck Institute for Chemistry, Mainz, Germany
| | - Tobias Kluge
- Ruprecht-Karls University Heidelberg, Institute of Environmental Physics, Heidelberg, Germany
| | - Gerald H Haug
- Climate Geochemistry Department, Max Planck Institute for Chemistry, Mainz, Germany
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Cui J, Tian L. Temperature issues in online extraction of water from plant and soil for stable isotope analysis. Rapid Commun Mass Spectrom 2020; 34:e8750. [PMID: 32048358 DOI: 10.1002/rcm.8750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 02/08/2020] [Accepted: 02/11/2020] [Indexed: 06/10/2023]
Affiliation(s)
- Jiangpeng Cui
- Key Laboratory of Tibetan Plateau Environment Change and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China
- Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - Lide Tian
- Key Laboratory of Tibetan Plateau Environment Change and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China
- CAS Centre for Excellence in Tibetan Plateau Earth Sciences, Beijing, 100101, China
- Institute of International Rivers and Eco-Security, Yunnan University, Kunming, 650091, China
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Marshall JD, Cuntz M, Beyer M, Dubbert M, Kuehnhammer K. Borehole Equilibration: Testing a New Method to Monitor the Isotopic Composition of Tree Xylem Water in situ. Front Plant Sci 2020; 11:358. [PMID: 32351515 PMCID: PMC7175398 DOI: 10.3389/fpls.2020.00358] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 03/11/2020] [Indexed: 05/27/2023]
Abstract
Forest water use has been difficult to quantify. One promising approach is to measure the isotopic composition of plant water, e.g., the transpired water vapor or xylem water. Because different water sources, e.g., groundwater versus shallow soil water, often show different isotopic signatures, isotopes can be used to investigate the depths from which plants take up their water and how this changes over time. Traditionally such measurements have relied on the extraction of wood samples, which provide limited time resolution at great expense, and risk possible artifacts. Utilizing a borehole drilled through a tree's stem, we propose a new method based on the notion that water vapor in a slow-moving airstream approaches isotopic equilibration with the much greater mass of liquid water in the xylem. We present two empirical data sets showing that the method can work in practice. We then present a theoretical model estimating equilibration times and exploring the limits at which the approach will fail. The method provides a simple, cheap, and accurate means of continuously estimating the isotopic composition of the source water for transpiration.
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Affiliation(s)
- John D. Marshall
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - Matthias Cuntz
- Université de Lorraine, AgroParisTech, INRAE, UMR Silva, Nancy, France
| | - Matthias Beyer
- IGOE, Umweltgeochemie, Technische Universität Braunschweig, Braunschweig, Germany
- Department B2.3: Groundwater Resources and Dynamics, German Federal Institute for Geosciences and Natural Resources (BGR), Hanover, Germany
| | - Maren Dubbert
- Ecosystem Physiology, University Freiburg, Freiburg, Germany
- IGB Berlin, Landscape Ecohydrology, Berlin, Germany
| | - Kathrin Kuehnhammer
- IGOE, Umweltgeochemie, Technische Universität Braunschweig, Braunschweig, Germany
- Ecosystem Physiology, University Freiburg, Freiburg, Germany
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Wu J, Li H, Niu J, Liu T, Zheng H, Xu X, Miao S. Water Uptake Patterns of Alfalfa under Winter Irrigation in Cold and Arid Grassland. Water 2020; 12:1093. [DOI: 10.3390/w12041093] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Crop reduction caused by cryogenesis and drought is a serious and global problem. The environmental stress caused by low temperature and drought during the overwintering stage of forage is the key factor leading to this low yield. In cold and arid grassland, winter irrigation can effectively alleviate the stress of alfalfa during overwintering, improve the survival rate of alfalfa, and significantly increase the yield. However, the water uptake patterns of alfalfa under winter irrigation are not clear, which are important to explore the mechanism of alleviating environmental stress by winter irrigation. In this research, the stable isotope compositions of all probable water sources and alfalfa xylem water were measured after winter irrigation. A graphical method was applied to identify the main soil layers with water uptake by the alfalfa roots. The contribution rate of available water sources to alfalfa xylem water was quantified by the MixSIAR (Bayesian isotope analysis mixing model in R) model. The results indicated that alfalfa absorbed soil water when the soil water content was high enough in the root layer when under high water volume freezing irrigation (irrigation in early winter when soil is freezing) but not under low and medium water volume freezing irrigation. Alfalfa gradually began to absorb soil water on the third day after thawing irrigation (irrigation in late winter when the soil is thawing) and showed different water uptake characteristics under low, medium, and high water volume. Thawing irrigation also accelerated the regeneration of alfalfa.
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25
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Galbács G, Kéri A, Kálomista I, Kovács-Széles É, Gornushkin IB. Deuterium analysis by inductively coupled plasma mass spectrometry using polyatomic species: An experimental study supported by plasma chemistry modeling. Anal Chim Acta 2020; 1104:28-37. [PMID: 32106954 DOI: 10.1016/j.aca.2020.01.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Revised: 11/20/2019] [Accepted: 01/05/2020] [Indexed: 11/25/2022]
Abstract
A new analytical method is proposed for the determination of deuterium (D) by ICP-MS. The method is based on the use of the signal from hydrogen-containing polyatomic ions formed in the inductively coupled plasma. Prior to analytical experiments, a theoretical study was performed to assess the concentration of polyatomic species present in an equilibrium Ar-O-D-H plasma, as a function of temperature and stoichiometric composition. It was established that the highest sensitivity and linearity measurement of D concentration in a wide range can be achieved by monitoring the ions of D2 and ArD, at masses 4 and 42, respectively. Results of the calculations are in good agreement with the experiments. Signal stability, spectral interferences, as well as the effect of plasma parameters were also assessed. Under optimized conditions, the limit of detection (LOD) was found to be 3 ppm atom fraction for deuterium when measured as ArD (in calcium and potassium free water), or 78 ppm when measured as D2. The achieved LOD values and the 4 to 5 orders of magnitude dynamic range easily allow the measurement of deuterium concentrations at around or above the natural level, up to nearly 100% (or 1 Mio ppm) in a standard quadrupole ICP-MS instrument. An even better performance is expected from the method in high resolution ICP-MS instruments equipped with low dead volume sample introduction systems.
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Affiliation(s)
- Gábor Galbács
- Department of Inorganic and Analytical Chemistry, University of Szeged, Dóm Square 7, 6720, Szeged, Hungary.
| | - Albert Kéri
- Department of Inorganic and Analytical Chemistry, University of Szeged, Dóm Square 7, 6720, Szeged, Hungary
| | - Ildikó Kálomista
- Department of Inorganic and Analytical Chemistry, University of Szeged, Dóm Square 7, 6720, Szeged, Hungary
| | - Éva Kovács-Széles
- Nuclear Security Department, MTA Centre for Energy Research, Konkoly Thege Miklós Street 29-33, 1121, Budapest, Hungary
| | - Igor B Gornushkin
- BAM Federal Institute for Materials Research and Testing, Richard-Willstaetter-Strasse 11, 12489, Berlin, Germany
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Hafner BD, Hesse BD, Bauerle TL, Grams TEE. Water potential gradient, root conduit size and root xylem hydraulic conductivity determine the extent of hydraulic redistribution in temperate trees. Funct Ecol 2020. [DOI: 10.1111/1365-2435.13508] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Benjamin D. Hafner
- Ecophysiology of Plants Technical University of Munich Freising Germany
- School of Integrative Plant Science Cornell University Ithaca NY USA
| | - Benjamin D. Hesse
- Ecophysiology of Plants Technical University of Munich Freising Germany
| | - Taryn L. Bauerle
- School of Integrative Plant Science Cornell University Ithaca NY USA
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Millar C, Pratt D, Schneider DJ, Koehler G, McDonnell JJ. Further experiments comparing direct vapor equilibration and cryogenic vacuum distillation for plant water stable isotope analysis. Rapid Commun Mass Spectrom 2019; 33:1850-1854. [PMID: 31306509 DOI: 10.1002/rcm.8530] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Revised: 07/09/2019] [Accepted: 07/09/2019] [Indexed: 06/10/2023]
Affiliation(s)
- Cody Millar
- Global Institute for Water Security, School of Environment and Sustainability, University of Saskatchewan, 11 Innovation Boulevard, Saskatoon, SK, S7N 3H5, Canada
| | - Dyan Pratt
- Global Institute for Water Security, School of Environment and Sustainability, University of Saskatchewan, 11 Innovation Boulevard, Saskatoon, SK, S7N 3H5, Canada
| | - David J Schneider
- Global Institute for Food Security, University of Saskatchewan, 110 Gymnasium Place, Saskatoon, SK, S7N 4J8, Canada
| | - Geoff Koehler
- NHRC Stable Isotope Laboratory, Environment and Climate Change Canada, 11 Innovation Boulevard, Saskatoon, SK, S7N 3H5, Canada
| | - Jeffrey J McDonnell
- Global Institute for Water Security, School of Environment and Sustainability, University of Saskatchewan, 11 Innovation Boulevard, Saskatoon, SK, S7N 3H5, Canada
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28
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Nehemy MF, Millar C, Janzen K, Gaj M, Pratt DL, Laroque CP, McDonnell JJ. 17 O-excess as a detector for co-extracted organics in vapor analyses of plant isotope signatures. Rapid Commun Mass Spectrom 2019; 33:1301-1310. [PMID: 31017711 DOI: 10.1002/rcm.8470] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 04/12/2019] [Accepted: 04/17/2019] [Indexed: 06/09/2023]
Abstract
RATIONALE The stable isotope compositions of hydrogen and oxygen in water (δ2 H and δ18 O values) have been widely used to investigate plant water sources, but traditional isotopic measurements of plant waters are expensive and labor intensive. Recent work with direct vapor equilibration (DVE) on laser spectroscopy has shown potential to side step limitations imposed by traditional methods. Here, we evaluate DVE analysis of plants with a focus on spectral contamination introduced by organic compounds. We present 17 O-excess as a way of quantifying organic compound interference in DVE. METHODS We performed isotopic analysis using the δ2 H, δ18 O and δ17 O values of water on an Off-Axis Integrated Cavity Output Spectroscopy (IWA-45EP OA-ICOS) instrument in vapor mode. We used a set of methanol (MeOH) and ethanol (EtOH) solutions to assess errors in isotope measurements. We evaluated how organic compounds affect the 17 O-excess. DVE was used to measure the isotopic signatures in natural plant material from Pinus banksiana, Picea mariana, and Larix laricina, and soil from boreal forest for comparison with solutions. RESULTS The 17 O-excess was sensitive to the presence of organic compounds in water. 17 O-excess changed proportionally to the concentration of MeOH per volume of water, resulting in positive values, while EtOH solutions resulted in smaller changes in the 17 O-excess. Soil samples did not show any spectral contamination. Plant samples were spectrally contaminated on the narrow-band and were enriched in 1 H and 16 O compared with source water. L. laricina was the only species that did not show any evidence of spectral contamination. Xylem samples that were spectrally contaminated had positive 17 O-excess values. CONCLUSIONS 17 O-excess can be a useful tool to identify spectral contamination and improve DVE plant and soil analysis in the laboratory and in situ. The 17 O-excess flagged the presence of MeOH and EtOH. Adding measurement of δ17 O values to traditional measurement of δ2 H and δ18 O values may shed new light on plant water analysis for source mixing dynamics using DVE.
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Affiliation(s)
- Magali F Nehemy
- Global Institute for Water Security, School of Environment and Sustainability, University of Saskatchewan, 11 Innovation Boulevard, Saskatoon, SK, S7N 3H5, Canada
| | - Cody Millar
- Global Institute for Water Security, School of Environment and Sustainability, University of Saskatchewan, 11 Innovation Boulevard, Saskatoon, SK, S7N 3H5, Canada
| | - Kim Janzen
- Global Institute for Water Security, School of Environment and Sustainability, University of Saskatchewan, 11 Innovation Boulevard, Saskatoon, SK, S7N 3H5, Canada
| | - Marcel Gaj
- Global Institute for Water Security, School of Environment and Sustainability, University of Saskatchewan, 11 Innovation Boulevard, Saskatoon, SK, S7N 3H5, Canada
| | - Dyan L Pratt
- Global Institute for Water Security, School of Environment and Sustainability, University of Saskatchewan, 11 Innovation Boulevard, Saskatoon, SK, S7N 3H5, Canada
| | - Colin P Laroque
- Global Institute for Water Security, School of Environment and Sustainability, University of Saskatchewan, 11 Innovation Boulevard, Saskatoon, SK, S7N 3H5, Canada
- Department of Soil Science, University of Saskatchewan, 51 Campus Drive, Saskatoon, SK, S7N 5A8, Canada
| | - Jeffrey J McDonnell
- Global Institute for Water Security, School of Environment and Sustainability, University of Saskatchewan, 11 Innovation Boulevard, Saskatoon, SK, S7N 3H5, Canada
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Wang J, Lu N, Fu B. Inter-comparison of stable isotope mixing models for determining plant water source partitioning. Sci Total Environ 2019; 666:685-693. [PMID: 30812003 DOI: 10.1016/j.scitotenv.2019.02.262] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2018] [Revised: 12/22/2018] [Accepted: 02/16/2019] [Indexed: 06/09/2023]
Abstract
Water sources used for plant identification coupled with stable isotopes are essential to improving the understanding of eco-hydrological processes and ecological management in water-limited ecosystems. Many approaches associated with stable isotopes have been used to determine plant water source apportionment. However, inter-comparisons of different methods are still limited, especially for Bayesian mixing models. In this study, we tested linear mixing models (IsoSource) and Bayesian models (SIAR, MixSIR and MixSIAR) to identify sources of water absorbed by Vitex negundo and Sophora viciifolia (shrubs) and Artemisia gmelinii (subshrub) during the growing season in the semiarid Loess Plateau. The results showed that there was no significant difference in the predicted plant water source fractions using only stable hydrogen isotope (δ2H) and only stable oxygen isotope (δ18O) with the IsoSource model. No significant difference was found in plant water source apportionment by the three Bayesian mixing models combined with δ2H and δ18O except for individual months. The SIAR and MixSIAR models detected no pronounced seasonal variations in plant water uptake, while the MixSIR model did detect seasonal variations. Overall, the SIAR and MixSIAR models exhibited relatively better water source apportionment performances than that of the MixSIR model. This discrepancy may be attributed to the difference in the post distribution simulation algorithm. This study provides critical insights into choosing a suitable method for identifying plant water source apportionment in arid and semiarid regions.
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Affiliation(s)
- Jian Wang
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Nan Lu
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Bojie Fu
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
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Millar C, Pratt D, Schneider DJ, McDonnell JJ. A comparison of extraction systems for plant water stable isotope analysis. Rapid Commun Mass Spectrom 2018; 32:1031-1044. [PMID: 29645300 DOI: 10.1002/rcm.8136] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 03/26/2018] [Accepted: 03/27/2018] [Indexed: 05/27/2023]
Abstract
RATIONALE The stable isotope ratios of water (δ2 H and δ18 O values) have been widely used to trace water in plants in a variety of physiological, ecohydrological, biogeochemical and hydrological studies. In such work, the analyte must first be extracted from samples, prior to isotopic analysis. While cryogenic vacuum distillation is currently the most widely used method reported in the literature, a variety of extraction-collection-analysis methods exist. A formal inter-method comparison on plant tissues has yet to be carried out. METHODS We performed an inter-method comparison of six plant water extraction techniques: direct vapour equilibration, microwave extraction, two unique versions of cryogenic vacuum distillation, centrifugation, and high-pressure mechanical squeezing. These methods were applied to four isotopically unique plant portions (head, stem, leaf, and root crown) of spring wheat (Triticum aestivum L.). Extracted plant water was analyzed via spectrometric (OA-ICOS) and mass-based (IRMS) analysis systems when possible. Spring wheat was grown under controlled conditions with irrigation inputs of a known isotopic composition. RESULTS The tested methods of extraction yielded markedly different isotopic signatures. Centrifugation, microwave extraction, direct vapour equilibration, and high-pressure mechanical squeezing produced water more enriched in 2 H and 18 O content. Both cryogenic vacuum distillation systems and the high-pressure mechanical squeezing method produced water more depleted in 2 H and 18 O content, depending upon the plant portion extracted. The various methods also produced differing concentrations of co-extracted organic compounds, depending on the mode of extraction. Overall, the direct vapor equilibration method outperformed all other methods. CONCLUSIONS Despite its popularity, cryogenic vacuum distillation was outperformed by the direct vapor equilibration method in terms of limited co-extraction of volatile organic compounds, rapid sample throughput, and near instantaneous returned stable isotope results. More research is now needed with other plant species, especially woody plants, to see how far the findings from this study could be extended.
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Affiliation(s)
- Cody Millar
- Global Institute for Water Security, School of Environment and Sustainability, University of Saskatchewan, 11 Innovation Boulevard, Saskatoon, SK, S7N 3H5, Canada
| | - Dyan Pratt
- Global Institute for Water Security, School of Environment and Sustainability, University of Saskatchewan, 11 Innovation Boulevard, Saskatoon, SK, S7N 3H5, Canada
| | - David J Schneider
- Global Institute for Food Security, University of Saskatchewan, 110 Gymnasium Place, Saskatoon, SK, S7N 4J8, Canada
| | - Jeffrey J McDonnell
- Global Institute for Water Security, School of Environment and Sustainability, University of Saskatchewan, 11 Innovation Boulevard, Saskatoon, SK, S7N 3H5, Canada
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Gerlein-safdi C, Gauthier PPG, Caylor KK. Dew-induced transpiration suppression impacts the water and isotope balances of Colocasia leaves. Oecologia 2018; 187:1041-51. [DOI: 10.1007/s00442-018-4199-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Accepted: 06/05/2018] [Indexed: 10/28/2022]
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Jézéquel T, Silvestre V, Dinis K, Giraudeau P, Akoka S. Optimized slice-selective 1H NMR experiments combined with highly accurate quantitative 13C NMR using an internal reference method. J Magn Reson 2018; 289:18-25. [PMID: 29448130 DOI: 10.1016/j.jmr.2018.02.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 01/31/2018] [Accepted: 02/04/2018] [Indexed: 06/08/2023]
Abstract
Isotope ratio monitoring by 13C NMR spectrometry (irm-13C NMR) provides the complete 13C intramolecular position-specific composition at natural abundance. It represents a powerful tool to track the (bio)chemical pathway which has led to the synthesis of targeted molecules, since it allows Position-specific Isotope Analysis (PSIA). Due to the very small composition range (which represents the range of variation of the isotopic composition of a given nuclei) of 13C natural abundance values (50‰), irm-13C NMR requires a 1‰ accuracy and thus highly quantitative analysis by 13C NMR. Until now, the conventional strategy to determine the position-specific abundance xi relies on the combination of irm-MS (isotopic ratio monitoring Mass Spectrometry) and 13C quantitative NMR. However this approach presents a serious drawback since it relies on two different techniques and requires to measure separately the signal of all the carbons of the analyzed compound, which is not always possible. To circumvent this constraint, we recently proposed a new methodology to perform 13C isotopic analysis using an internal reference method and relying on NMR only. The method combines a highly quantitative 1H NMR pulse sequence (named DWET) with a 13C isotopic NMR measurement. However, the recently published DWET sequence is unsuited for samples with short T1, which forms a serious limitation for irm-13C NMR experiments where a relaxing agent is added. In this context, we suggest two variants of the DWET called Multi-WET and Profiled-WET, developed and optimized to reach the same accuracy of 1‰ with a better immunity towards T1 variations. Their performance is evaluated on the determination of the 13C isotopic profile of vanillin. Both pulse sequences show a 1‰ accuracy with an increased robustness to pulse miscalibrations compared to the initial DWET method. This constitutes a major advance in the context of irm-13C NMR since it is now possible to perform isotopic analysis with high relaxing agent concentrations, leading to a strong reduction of the overall experiment time.
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Affiliation(s)
- Tangi Jézéquel
- Université de Nantes, CNRS, CEISAM UMR 6230, Nantes, France.
| | | | - Katy Dinis
- Université de Nantes, CNRS, CEISAM UMR 6230, Nantes, France
| | - Patrick Giraudeau
- Université de Nantes, CNRS, CEISAM UMR 6230, Nantes, France; Institut Universitaire de France, Paris, France
| | - Serge Akoka
- Université de Nantes, CNRS, CEISAM UMR 6230, Nantes, France
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Wassenaar LI, Terzer-Wassmuth S, Douence C, Araguas-Araguas L, Aggarwal PK, Coplen TB. Seeking excellence: An evaluation of 235 international laboratories conducting water isotope analyses by isotope-ratio and laser-absorption spectrometry. Rapid Commun Mass Spectrom 2018; 32:393-406. [PMID: 29315909 DOI: 10.1002/rcm.8052] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Revised: 12/15/2017] [Accepted: 12/18/2017] [Indexed: 06/07/2023]
Abstract
RATIONALE Water stable isotope ratios (δ2 H and δ18 O values) are widely used tracers in environmental studies; hence, accurate and precise assays are required for providing sound scientific information. We tested the analytical performance of 235 international laboratories conducting water isotope analyses using dual-inlet and continuous-flow isotope ratio mass spectrometers and laser spectrometers through a water isotope inter-comparison test. METHODS Eight test water samples were distributed by the IAEA to international stable isotope laboratories. These consisted of a core set of five samples spanning the common δ-range of natural waters, and three optional samples (highly depleted, enriched, and saline). The fifth core sample contained unrevealed trace methanol to assess analyst vigilance to the impact of organic contamination on water isotopic measurements made by all instrument technologies. RESULTS For the core and optional samples ~73 % of laboratories gave acceptable results within 0.2 ‰ and 1.5 ‰ of the reference values for δ18 O and δ2 H, respectively; ~27 % produced unacceptable results. Top performance for δ18 O values was dominated by dual-inlet IRMS laboratories; top performance for δ2 H values was led by laser spectrometer laboratories. Continuous-flow instruments yielded comparatively intermediate results. Trace methanol contamination of water resulted in extreme outlier δ-values for laser instruments, but also affected reactor-based continuous-flow IRMS systems; however, dual-inlet IRMS δ-values were unaffected. CONCLUSIONS Analysis of the laboratory results and their metadata suggested inaccurate or imprecise performance stemmed mainly from skill- and knowledge-based errors including: calculation mistakes, inappropriate or compromised laboratory calibration standards, poorly performing instrumentation, lack of vigilance to contamination, or inattention to unreasonable isotopic outcomes. To counteract common errors, we recommend that laboratories include 1-2 'known' control standards in all autoruns; laser laboratories should screen each autorun for spectral contamination; and all laboratories should evaluate whether derived d-excess values are realistic when both isotope ratios are measured. Combined, these data evaluation strategies should immediately inform the laboratory about fundamental mistakes or compromised samples.
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Affiliation(s)
- L I Wassenaar
- International Atomic Energy Agency, Isotope Hydrology Section, PO Box 100, A-1400, Vienna, Austria
| | - S Terzer-Wassmuth
- International Atomic Energy Agency, Isotope Hydrology Section, PO Box 100, A-1400, Vienna, Austria
| | - C Douence
- International Atomic Energy Agency, Isotope Hydrology Section, PO Box 100, A-1400, Vienna, Austria
| | - L Araguas-Araguas
- International Atomic Energy Agency, Isotope Hydrology Section, PO Box 100, A-1400, Vienna, Austria
| | - P K Aggarwal
- International Atomic Energy Agency, Isotope Hydrology Section, PO Box 100, A-1400, Vienna, Austria
| | - T B Coplen
- US Geological Survey, 431 National Center, 12201Sunrise Valley Drive, Reston, VA, 20192, USA
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Affiliation(s)
- Jens Atzrodt
- Isotope Chemistry and Metabolite Synthesis, Integrated Drug Discovery, Medicinal Chemistry; Industriepark Höchst, G876 65926 Frankfurt Deutschland
| | - Volker Derdau
- Isotope Chemistry and Metabolite Synthesis, Integrated Drug Discovery, Medicinal Chemistry; Industriepark Höchst, G876 65926 Frankfurt Deutschland
| | - William J. Kerr
- Department of Pure and Applied Chemistry, WestCHEM; University of Strathclyde; 295 Cathedral Street Glasgow Scotland G1 1XL Großbritannien
| | - Marc Reid
- Department of Pure and Applied Chemistry, WestCHEM; University of Strathclyde; 295 Cathedral Street Glasgow Scotland G1 1XL Großbritannien
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Atzrodt J, Derdau V, Kerr WJ, Reid M. Deuterium- and Tritium-Labelled Compounds: Applications in the Life Sciences. Angew Chem Int Ed Engl 2018; 57:1758-1784. [PMID: 28815899 DOI: 10.1002/anie.201704146] [Citation(s) in RCA: 391] [Impact Index Per Article: 65.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 07/27/2017] [Indexed: 12/19/2022]
Abstract
Hydrogen isotopes are unique tools for identifying and understanding biological and chemical processes. Hydrogen isotope labelling allows for the traceless and direct incorporation of an additional mass or radioactive tag into an organic molecule with almost no changes in its chemical structure, physical properties, or biological activity. Using deuterium-labelled isotopologues to study the unique mass-spectrometric patterns generated from mixtures of biologically relevant molecules drastically simplifies analysis. Such methods are now providing unprecedented levels of insight in a wide and continuously growing range of applications in the life sciences and beyond. Tritium (3 H), in particular, has seen an increase in utilization, especially in pharmaceutical drug discovery. The efforts and costs associated with the synthesis of labelled compounds are more than compensated for by the enhanced molecular sensitivity during analysis and the high reliability of the data obtained. In this Review, advances in the application of hydrogen isotopes in the life sciences are described.
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Affiliation(s)
- Jens Atzrodt
- Isotope Chemistry and Metabolite Synthesis, Integrated Drug Discovery, Medicinal Chemistry, Industriepark Höchst, G876, 65926, Frankfurt, Germany
| | - Volker Derdau
- Isotope Chemistry and Metabolite Synthesis, Integrated Drug Discovery, Medicinal Chemistry, Industriepark Höchst, G876, 65926, Frankfurt, Germany
| | - William J Kerr
- Department of Pure and Applied Chemistry, WestCHEM, University of Strathclyde, 295 Cathedral Street, Glasgow, Scotland, G1 1XL, UK
| | - Marc Reid
- Department of Pure and Applied Chemistry, WestCHEM, University of Strathclyde, 295 Cathedral Street, Glasgow, Scotland, G1 1XL, UK
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Bauska TK, Walters G, Gázquez F, Hodell DA. Online Differential Thermal Isotope Analysis of Hydration Water in Minerals by Cavity Ringdown Laser Spectroscopy. Anal Chem 2018; 90:752-759. [PMID: 29131947 PMCID: PMC5789391 DOI: 10.1021/acs.analchem.7b03136] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We have developed a new method for measuring the isotopic composition (δ18O and δD) of different types of bonded water (e.g., molecular water, hydroxyl) contained in hydrated minerals by coupling a thermal gravimeter (TG) and a cavity ringdown laser spectrometer (CRDS). The method involves precisely step-heating a mineral sample, allowing the separation of the different types of waters that are released at different temperatures. Simultaneously, the water vapor evolved from the mineral sample is analyzed for oxygen and hydrogen isotopes by CRDS. Isotopic values for the separate peaks are calculated by integrating the product of the water amounts and its isotopic values, after correcting for background. We provide examples of the application of the differential thermal isotope analysis (DTIA) method to a variety of hydrous minerals and mineraloids including gypsum, clays, and amorphous silica (opal). The isotopic compositions of the total water evolved from a set of natural gypsum samples by DTIA are compared with the results of a conventional offline water extraction method followed by CRDS analysis. The results from both methods are in excellent agreement, and precisions (1σ) for δ18O (±0.12‰) and δD (±0.8‰) of the total gypsum hydration water from the DTIA method are comparable to that obtained by the offline method. A range of analytical challenges and solutions (e.g., spectroscopic interferences produced by VOCs in natural samples, isotopic exchange with structural oxygen, etc.) are discussed. The DTIA method has wide ranging applications for addressing fundamental problems across many disciplines in earth and planetary sciences, including paleoclimatology, sedimentology, volcanology, water exchange between the solid earth and hydrosphere, and water on Mars and other planetary bodies.
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Affiliation(s)
- T K Bauska
- Godwin Laboratory for Palaeoclimate Research, Department of Earth Sciences, University of Cambridge , Downing Street, Cambridge CB2 3EQ, United Kingdom
| | - G Walters
- Godwin Laboratory for Palaeoclimate Research, Department of Earth Sciences, University of Cambridge , Downing Street, Cambridge CB2 3EQ, United Kingdom
| | - F Gázquez
- Godwin Laboratory for Palaeoclimate Research, Department of Earth Sciences, University of Cambridge , Downing Street, Cambridge CB2 3EQ, United Kingdom
| | - D A Hodell
- Godwin Laboratory for Palaeoclimate Research, Department of Earth Sciences, University of Cambridge , Downing Street, Cambridge CB2 3EQ, United Kingdom
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Wang J, Fu B, Lu N, Zhang L. Seasonal variation in water uptake patterns of three plant species based on stable isotopes in the semi-arid Loess Plateau. Sci Total Environ 2017; 609:27-37. [PMID: 28734247 DOI: 10.1016/j.scitotenv.2017.07.133] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2017] [Revised: 07/14/2017] [Accepted: 07/14/2017] [Indexed: 06/07/2023]
Abstract
Water is a limiting factor and significant driving force for ecosystem processes in arid and semi-arid areas. Knowledge of plant water uptake pattern is indispensable for understanding soil-plant interactions and species coexistence. The 'Grain for Green' project that started in 1999 in the Loess Plateau of China has led to large scale vegetation change. However, little is known about the water uptake patterns of the main plant species that inhabit in this region. In this study, the seasonal variations in water uptake patterns of three representative plant species, Stipa bungeana, Artemisia gmelinii and Vitex negundo, that are widely distributed in the semi-arid area of the Loess Plateau, were identified by using dual stable isotopes of δ2H and δ18O in plant and soil water coupled with a Bayesian mixing model MixSIAR. The soil water at the 0-120cm depth contributed 79.54±6.05% and 79.94±8.81% of the total water uptake of S. bungeana and A. gmelinii, respectively, in the growing season. The 0-40cm soil contributed the most water in July (74.20±15.20%), and the largest proportion of water (33.10±15.20%) was derived from 120-300cm soils in August for A. gmelinii. However, V. negundo obtained water predominantly from surface soil horizons (0-40cm) and then switched to deep soil layers (120-300cm) as the season progressed. This suggested that V. negundo has a greater degree of ecological plasticity as it could explore water sources from deeper soils as the water stress increased. This capacity can mainly be attributed to its functionally dimorphic root system. V. negundo may have a competitive advantage when encountering short-term drought. The ecological plasticity of plant water use needs to be considered in plant species selection and ecological management and restoration of the arid and semi-arid ecosystems in the Loess Plateau.
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Affiliation(s)
- Jian Wang
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Bojie Fu
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Nan Lu
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
| | - Li Zhang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
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Gerlein-Safdi C, Gauthier PPG, Sinkler CJ, Caylor KK. Leaf water 18 O and 2 H maps show directional enrichment discrepancy in Colocasia esculenta. Plant Cell Environ 2017; 40:2095-2108. [PMID: 28658718 DOI: 10.1111/pce.13002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2016] [Revised: 05/31/2017] [Accepted: 06/02/2017] [Indexed: 06/07/2023]
Abstract
Spatial patterns of leaf water isotopes are challenging to predict because of the intricate link between vein and lamina water. Many models have attempted to predict these patterns, but to date, most have focused on monocots with parallel veins. These provide a simple system to study, but do not represent the majority of plant species. Here, a new protocol is developed using a Picarro induction module coupled to a cavity ringdown spectrometer to obtain maps of the leaf water isotopes (18 O and 2 H). The technique is applied to Colocasia esculenta leaves. The results are compared with isotope ratio mass spectrometry. In C. esculenta, a large enrichment in the radial direction is observed, but not in the longitudinal direction. The string-of-lakes model fails to predict the observed patterns, while the Farquhar-Gan model is more successful, especially when enrichment is accounted for along the radial direction. Our results show that reticulate-veined leaves experience a larger enrichment along the axis of the secondary veins than along the midrib. We hypothesize that this is due to the lower major/minor vein ratio that leads to longer pathways between major veins and sites of evaporation.
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Affiliation(s)
- Cynthia Gerlein-Safdi
- Department of Civil and Environmental Engineering, Princeton University, Princeton, NJ, 08544, USA
| | - Paul P G Gauthier
- Department of Geosciences, Princeton University, Princeton, NJ, 08544, USA
- Department of Biology, University of New Mexico, Albuquerque, NM, 87131, USA
| | - Craig James Sinkler
- Department of Geological, Environmental, and Marine Sciences, Rider University, Lawrenceville, NJ, 08648, USA
- EarthRes Group Inc., Pipersville, PA, 18947, USA
| | - Kelly Krispin Caylor
- Department of Civil and Environmental Engineering, Princeton University, Princeton, NJ, 08544, USA
- Department of Geography, UC Santa Barbara, Santa Barbara, CA, 93106, USA
- Bren School of Environmental Science and Management, UC Santa Barbara, Santa Barbara, CA, 93106, USA
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Geris J, Tetzlaff D, McDonnell JJ, Soulsby C. Spatial and temporal patterns of soil water storage and vegetation water use in humid northern catchments. Sci Total Environ 2017; 595:486-493. [PMID: 28395263 DOI: 10.1016/j.scitotenv.2017.03.275] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 03/26/2017] [Accepted: 03/30/2017] [Indexed: 06/07/2023]
Abstract
Using stable isotope data from soil and vegetation xylem samples across a range of landscape positions, this study provides preliminary insights into spatial patterns and temporal dynamics of soil-plant water interactions in a humid, low-energy northern environment. Our analysis showed that evaporative fractionation affected the isotopic signatures in soil water at shallow depths but was less marked than previously observed in other environments. By comparing the temporal dynamics of stable isotopes in soil water mainly held at suctions around and below field capacity, we found that these waters are not clearly separated. The study inferred that vegetation water sources at all sites were relatively constant, and most likely to be in the upper profile close to the soil/atmosphere interface. The data analyses also suggested that both vegetation type and landscape position, including soil type, may have a strong influence on local water uptake patterns, although more work is needed to explicitly identify water sources and understand the effect of plant physiological processes on xylem isotopic water signatures.
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Affiliation(s)
- Josie Geris
- Northern Rivers Institute, School of Geosciences, University of Aberdeen, Aberdeen, Scotland, United Kingdom.
| | - Doerthe Tetzlaff
- Northern Rivers Institute, School of Geosciences, University of Aberdeen, Aberdeen, Scotland, United Kingdom
| | - Jeffrey J McDonnell
- Northern Rivers Institute, School of Geosciences, University of Aberdeen, Aberdeen, Scotland, United Kingdom; Global Institute for Water Security, National Hydrology Research Centre, University of Saskatchewan, Saskatoon, Canada
| | - Chris Soulsby
- Northern Rivers Institute, School of Geosciences, University of Aberdeen, Aberdeen, Scotland, United Kingdom
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Hafner BD, Tomasella M, Häberle KH, Goebel M, Matyssek R, Grams TEE. Hydraulic redistribution under moderate drought among English oak, European beech and Norway spruce determined by deuterium isotope labeling in a split-root experiment. Tree Physiol 2017; 37:950-960. [PMID: 28541559 DOI: 10.1093/treephys/tpx050] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Accepted: 05/02/2017] [Indexed: 06/07/2023]
Abstract
Hydraulic redistribution (HR) of soil water through plant roots is a crucial phenomenon improving the water balance of plants and ecosystems. It is mostly described under severe drought, and not yet studied under moderate drought. We tested the potential of HR under moderate drought, hypothesizing that (H1) tree species redistribute soil water in their roots even under moderate drought and that (H2) neighboring plants are supported with water provided by redistributing plants. Trees were planted in split-root systems with one individual (i.e., split-root plant, SRP) having its roots divided between two pots with one additional tree each. Species were 2- to 4-year-old English oak (Quercus robur L.), European beech (Fagus sylvatica L.) and Norway spruce (Picea abies (L.) Karst). A gradient in soil water potential (ψsoil) was established between the two pots (-0.55 ± 0.02 MPa and -0.29 ± 0.03 MPa), and HR was observed by labeling with deuterium-enriched water. Irrespective of species identity, 93% of the SRPs redistributed deuterium enriched water from the moist to the drier side, supporting H1. Eighty-eight percent of the plants in the drier pots were deuterium enriched in their roots, with 61 ± 6% of the root water originating from SRP roots. Differences in HR among species were related to their root anatomy with diffuse-porous xylem structure in both beech and-opposing the stem structure-oak roots. In spruce, we found exclusively tracheids. We conclude that water can be redistributed within roots of different tree species along a moderate ψsoil gradient, accentuating HR as an important water source for drought-stressed plants, with potential implications for ecohydrological and plant physiological sciences. It remains to be shown to what extent HR occurs under field conditions in Central Europe.
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Affiliation(s)
- Benjamin D Hafner
- Ecophysiology of Plants, Technische Universität München, Hans-Carl-von-Carlowitz-Platz 2, 85354 Freising, Germany
| | - Martina Tomasella
- Ecophysiology of Plants, Technische Universität München, Hans-Carl-von-Carlowitz-Platz 2, 85354 Freising, Germany
| | - Karl-Heinz Häberle
- Ecophysiology of Plants, Technische Universität München, Hans-Carl-von-Carlowitz-Platz 2, 85354 Freising, Germany
| | - Marc Goebel
- Department of Natural Resources, Cornell University, Ithaca, NY 14853, USA
| | - Rainer Matyssek
- Ecophysiology of Plants, Technische Universität München, Hans-Carl-von-Carlowitz-Platz 2, 85354 Freising, Germany
| | - Thorsten E E Grams
- Ecophysiology of Plants, Technische Universität München, Hans-Carl-von-Carlowitz-Platz 2, 85354 Freising, Germany
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Kerhoulas L, Kolb T, Koch G. The Influence of Monsoon Climate on Latewood Growth of Southwestern Ponderosa Pine. Forests 2017; 8:140. [DOI: 10.3390/f8050140] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Cui J, Tian L, Gerlein-Safdi C, Qu D. The influence of memory, sample size effects, and filter paper material on online laser-based plant and soil water isotope measurements. Rapid Commun Mass Spectrom 2017; 31:509-522. [PMID: 28072488 DOI: 10.1002/rcm.7824] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Revised: 01/06/2017] [Accepted: 01/07/2017] [Indexed: 06/06/2023]
Abstract
RATIONALE The recent development of isotope ratio infrared spectroscopy (IRIS) was quickly followed by the addition of online extraction and analysis systems, making it faster and easier to measure soil and plant water isotopes. However, memory and sample size effects limit the efficiency and accuracy of these new setups. In response, this study presents a scheme dedicated to estimating and eliminating these two effects. METHODS Memory effect was determined by injecting two standard waters alternately. Each standard was injected nine times in a row and analyzed using induction module cavity ring-down spectroscopy (IM-CRDS). Memory coefficients were calculated using a new "multistage jump" algorithm. Sample size effects were evaluated by injecting water volumes ranging from 1 μL to 6 μL. Finally, the influence of cellulose filter paper on the isotopic measurements, the memory, and the sample size effect was evaluated by comparing it with glass filter paper. RESULTS Memory effects were detected for both δ18 O and δ2 H values, with the latter being stronger. Isotopic differences between replicates of the same plant or soil sample showed a clear decrease after memory correction. A small water volume effect was found only when the injected water volume was larger than 3 μL. However, while the correction method performed well for laboratory-made samples, it did not for field samples, due to the heterogeneity of the isotopic composition of the samples. Stronger memory and water volume effects were found for cellulose filter paper. CONCLUSIONS The memory coefficients and the water volume-isotope relationship improved the consistency and accuracy of both laboratory and field data. Our results indicate that cellulose filter paper may not be a suitable medium to measure standard waters and evaluate memory and water volume effects. Finally, a detailed correction and calibration protocol is suggested, along with notes on best practices to obtain good-quality IM-CRDS data. Copyright © 2017 John Wiley & Sons, Ltd.
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Affiliation(s)
- Jiangpeng Cui
- Key Laboratory of Tibetan Plateau Environment Change and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Lide Tian
- Key Laboratory of Tibetan Plateau Environment Change and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China
- CAS Centre for Excellence in Tibetan Plateau Earth Sciences, Beijing, 100101, China
| | - Cynthia Gerlein-Safdi
- Department of Civil and Environmental Engineering, Princeton University, Princeton, NJ, 08540, USA
| | - Dongmei Qu
- Key Laboratory of Tibetan Plateau Environment Change and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China
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Johnson JE, Hamann L, Dettman DL, Kim-Hak D, Leavitt SW, Monson RK, Papuga SA. Performance of induction module cavity ring-down spectroscopy (IM-CRDS) for measuring δ 18 O and δ 2 H values of soil, stem, and leaf waters. Rapid Commun Mass Spectrom 2017; 31:547-560. [PMID: 28010033 DOI: 10.1002/rcm.7813] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2016] [Revised: 12/19/2016] [Accepted: 12/20/2016] [Indexed: 06/06/2023]
Abstract
RATIONALE Induction module cavity ring-down spectroscopy (IM-CRDS) has been proposed as a rapid and cost-effective alternative to cryogenic vacuum distillation (CVD) and isotope ratio mass spectrometry (IRMS) for the measurement of δ18 O and δ2 H values in matrix-bound waters. In the current study, we characterized the performance of IM-CRDS relative to CVD and IRMS and investigated the mechanisms responsible for differences between the methods. METHODS We collected a set of 75 soil, stem, and leaf water samples, and measured the δ18 O and δ2 H values of each sample with four techniques: CVD and IRMS, CVD and CRDS, CVD and IM-CRDS, and IM-CRDS alone. We then calculated the isotopic errors for each of the three CRDS methods relative to CVD and IRMS, and analyzed the relationships among these errors and suites of diagnostic spectral parameters that are indicative of organic contamination. RESULTS The IM-CRDS technique accurately assessed the δ18 O and δ2 H values of pure waters, but exhibited progressively increasing errors for soil waters, stem waters, and leaf waters. For soils, the errors were attributable to subsampling of isotopically heterogeneous source material, whereas for stems and leaves, they were attributable to spectral interference. Unexpectedly, the magnitude of spectral interference was higher for the solid samples analyzed directly via IM-CRDS than for those originally extracted via CVD and then analyzed by IM-CRDS. CONCLUSIONS There are many types of matrix-bound water samples for which IM-CRDS measurements include significant errors from spectral interference. As a result, spectral analysis and validation should be incorporated into IM-CRDS post-processing procedures. In the future, IM-CRDS performance could be improved through: (i) identification of the compounds that cause spectral interference, and either (ii) modification of the combustion step to completely oxidize these compounds to CO2 , and/or (iii) incorporation of corrections for these compounds into the spectral fitting models used by the CRDS analyzers. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
- J E Johnson
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ, 85721, USA
- Department of Global Ecology, Carnegie Institution, 260 Panama Street, Stanford, CA, 94305, USA
| | - L Hamann
- School of Natural Resources and the Environment, University of Arizona, Tucson, AZ, 85721, USA
| | - D L Dettman
- Department of Geosciences, University of Arizona, Tucson, AZ, 85721, USA
| | - D Kim-Hak
- Picarro, Inc., 3105 Patrick Henry Drive, Santa Clara, CA, 95054, USA
| | - S W Leavitt
- Laboratory of Tree-Ring Research, University of Arizona, Tucson, AZ, 85721, USA
| | - R K Monson
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ, 85721, USA
- Laboratory of Tree-Ring Research, University of Arizona, Tucson, AZ, 85721, USA
| | - S A Papuga
- School of Natural Resources and the Environment, University of Arizona, Tucson, AZ, 85721, USA
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Sprenger M, Tetzlaff D, Soulsby C. No influence of CO 2 on stable isotope analyses of soil waters with off-axis integrated cavity output spectroscopy (OA-ICOS). Rapid Commun Mass Spectrom 2017; 31:430-436. [PMID: 28024164 PMCID: PMC5324620 DOI: 10.1002/rcm.7815] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Revised: 12/22/2016] [Accepted: 12/23/2016] [Indexed: 05/17/2023]
Abstract
RATIONALE It was recently shown that the presence of CO2 affects the stable isotope (δ2 H and δ18 O values) analysis of water vapor via Wavelength-Scanned Cavity Ring-Down Spectroscopy. Here, we test how much CO2 is emitted from soil samples and if the CO2 in the headspace influences the isotope analysis with the direct equilibration method by Off-Axis Integrated Cavity Output Spectroscopy (OA-ICOS). METHODS The headspace above different amounts of sparkling water was sampled, and its stable isotopic composition (δ2 H and δ18 O values) and CO2 concentration were measured by direct equilibration and by gas chromatography, respectively. In addition, the headspace above soil samples was analyzed in the same way. Furthermore, the gravimetric water content and the loss on ignition were measured for the soil samples. RESULTS The experiment with the sparkling water showed that CO2 does not influence the stable isotope analysis by OA-ICOS. CO2 was emitted from the soil samples and correlated with the isotopic fractionation signal, but no causal relationship between the two was determined. Instead, the fractionation signal in pore water isotopes can be explained by soil evaporation and the CO2 can be related to soil moisture and organic matter which both enhance microbial activity. CONCLUSIONS We found, despite the high CO2 emissions from soil samples, no need for a post-correction of the pore water stable isotope analysis results, since there is no relation between CO2 concentrations and the stable isotope results of vapor samples obtained with OA-ICOS. © 2016 The Authors. Rapid Communications in Mass Spectrometry Published by John Wiley & Sons Ltd.
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Affiliation(s)
- Matthias Sprenger
- Northern Rivers Institute, School of GeosciencesUniversity of AberdeenElphinstone RoadAberdeenAB24 3UFUK
| | - Doerthe Tetzlaff
- Northern Rivers Institute, School of GeosciencesUniversity of AberdeenElphinstone RoadAberdeenAB24 3UFUK
| | - Chris Soulsby
- Northern Rivers Institute, School of GeosciencesUniversity of AberdeenElphinstone RoadAberdeenAB24 3UFUK
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Jézéquel T, Joubert V, Giraudeau P, Remaud GS, Akoka S. The new face of isotopic NMR at natural abundance. Magn Reson Chem 2017; 55:77-90. [PMID: 27921330 DOI: 10.1002/mrc.4548] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 10/28/2016] [Accepted: 11/02/2016] [Indexed: 05/26/2023]
Abstract
The most widely used method for isotope analysis at natural abundance is isotope ratio monitoring by Mass Spectrometry (irm-MS) which provides bulk isotopic composition in 2 H, 13 C, 15 N, 18 O or 34 S. However, in the 1980s, the direct access to Site-specific Natural Isotope Fractionation by Nuclear Magnetic Resonance (SNIF-NMRTM ) was immediately recognized as a powerful technique to authenticate the origin of natural or synthetic products. The initial - and still most popular - application consisted in detecting the chaptalization of wines by irm-2 H NMR. The approach has been extended to a wide range of methodologies over the last decade, paving the way to a wide range of applications, not only in the field of authentication but also to study metabolism. In particular, the emerging irm-13 C NMR approach delivers direct access to position-specific 13 C isotope content at natural abundance. After highlighting the application scope of irm-NMR (2 H and 13 C), this article describes the major improvements which made possible to reach the required accuracy of 1‰ (0.1%) in irm-13 C NMR. The last part of the manuscript summarizes the different steps to perform isotope analysis as a function of the sample properties (concentration, peak overlap) and the kind of targeted isotopic information (authentication, affiliation). Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
- Tangi Jézéquel
- Université de Nantes, CNRS, CEISAM UMR 6230, Nantes, France
| | | | - Patrick Giraudeau
- Université de Nantes, CNRS, CEISAM UMR 6230, Nantes, France
- Institut Universitaire de France, Paris, France
| | | | - Serge Akoka
- Université de Nantes, CNRS, CEISAM UMR 6230, Nantes, France
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Schauer AJ, Schoenemann SW, Steig EJ. Routine high-precision analysis of triple water-isotope ratios using cavity ring-down spectroscopy. Rapid Commun Mass Spectrom 2016; 30:2059-2069. [PMID: 27469283 DOI: 10.1002/rcm.7682] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Revised: 06/13/2016] [Accepted: 07/08/2016] [Indexed: 06/06/2023]
Abstract
RATIONALE Water isotope analysis for δ(2) H and δ(18) O values via laser spectroscopy is routine for many laboratories. While recent work has added the δ(17) O value to the high-precision suite, it does not follow that researchers will routinely obtain high precision (17) O excess (Δ(17) O). We demonstrate the routine acquisition of high-precision δ(2) H, δ(17) O, δ(18) O, d, and Δ(17) O values using a commercially available laser spectroscopy instrument. METHODS We use a Picarro L2140-i cavity ring-down spectroscopy analyzer with discrete liquid injections into an A0211 vaporization module by a Leap Technologies LC PAL autosampler. The instrument is run in two modes: (1) as recommended by the manufacturer (default mode) and (2) after modifying select default settings and using alternative data types (advanced mode). Reference waters analyzed over the course of 15 months while running unknown samples are used to assess system performance. RESULTS The default mode provides precision for δ(2) H, δ(17) O, δ(18) O, d, and Δ(17) O values that may be sufficient for many applications. When using the advanced mode, we reach a higher level of precision for δ(2) H, δ(17) O, δ(18) O, d, and Δ(17) O values (0.4 mUr, 0.04 mUr, 0.07 mUr, 0.5 mUr, and 8 μUr, respectively, where mUr = 0.001 = ‰, and μUr = 10(-6) ) in a shorter amount of time and with fewer syringe actuations than in the default mode. The improved performance results from an increase in the total integration time for each injected water pulse. CONCLUSIONS Our recommended approach for routine δ(2) H, δ(17) O, δ(18) O, d and Δ(17) O measurements with the Picarro L2140-i is to make use of conditioning vials, use fewer injections (5 per vial) with greater pulse duration (520 seconds (s) per injection) and use only the first 120 s for δ(2) H measurements and all 520 s for δ(17) O and δ(18) O measurements. Although the sample throughput is 10 unknowns per day, our optimal approach reduces the number of syringe actuations, the effect of memory, and the total analysis time, while improving precision relative to the default approach. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
- Andrew J Schauer
- IsoLab, Department of Earth and Space Sciences, University of Washington, Seattle, WA, 98195, USA
| | - Spruce W Schoenemann
- IsoLab, Department of Earth and Space Sciences, University of Washington, Seattle, WA, 98195, USA
| | - Eric J Steig
- IsoLab, Department of Earth and Space Sciences, University of Washington, Seattle, WA, 98195, USA
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Volkmann THM, Kühnhammer K, Herbstritt B, Gessler A, Weiler M. A method for in situ monitoring of the isotope composition of tree xylem water using laser spectroscopy. Plant Cell Environ 2016; 39:2055-63. [PMID: 27260852 DOI: 10.1111/pce.12725] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Revised: 01/26/2016] [Accepted: 01/27/2016] [Indexed: 05/27/2023]
Abstract
Field studies analyzing the stable isotope composition of xylem water are providing important information on ecosystem water relations. However, the capacity of stable isotopes to characterize the functioning of plants in their environment has not been fully explored because of methodological constraints on the extent and resolution at which samples could be collected and analysed. Here, we introduce an in situ method offering the potential to continuously monitor the stable isotope composition of tree xylem water via its vapour phase using a commercial laser-based isotope analyser and compact microporous probes installed into the xylem. Our technique enables efficient high-frequency measurement with intervals of only a few minutes per sample while eliminating the need for costly and cumbersome destructive collection of plant material and laboratory-based processing. We present field observations of xylem water hydrogen and oxygen isotope compositions obtained over several days including a labelled irrigation event and compare them against results from concurrent destructive sampling with cryogenic distillation and mass spectrometric analysis. The data demonstrate that temporal changes as well as spatial patterns of integration in xylem water isotope composition can be resolved through direct measurement. The new technique can therefore present a valuable tool to study the hydraulic architecture and water utilization of trees.
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Affiliation(s)
- Till H M Volkmann
- Chair of Hydrology, Faculty of Environment and Natural Resources, University of Freiburg, Fahnenbergplatz, 79098, Freiburg, Germany
- Biosphere 2 Earth Science, University of Arizona, 845 N. Park Avenue, Tucson, AZ, 85721, USA
| | - Kathrin Kühnhammer
- Chair of Hydrology, Faculty of Environment and Natural Resources, University of Freiburg, Fahnenbergplatz, 79098, Freiburg, Germany
| | - Barbara Herbstritt
- Chair of Hydrology, Faculty of Environment and Natural Resources, University of Freiburg, Fahnenbergplatz, 79098, Freiburg, Germany
| | - Arthur Gessler
- Institute for Landscape Biogeochemistry, Leibniz Centre for Agricultural Landscape Research (ZALF), Eberswalder Straße 84, 15374, Müncheberg, Germany
- Research Unit Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Zürcherstrasse 111, 8903, Birmensdorf, Switzerland
- Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstrasse 6, 14195, Berlin, Germany
| | - Markus Weiler
- Chair of Hydrology, Faculty of Environment and Natural Resources, University of Freiburg, Fahnenbergplatz, 79098, Freiburg, Germany
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Zhao L, Wang L, Cernusak LA, Liu X, Xiao H, Zhou M, Zhang S. Significant Difference in Hydrogen Isotope Composition Between Xylem and Tissue Water in Populus Euphratica. Plant Cell Environ 2016; 39:1848-1857. [PMID: 27061571 DOI: 10.1111/pce.12753] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Revised: 04/03/2016] [Accepted: 04/04/2016] [Indexed: 06/05/2023]
Abstract
Deuterium depletions between stem water and source water have been observed in coastal halophyte plants and in multiple species under greenhouse conditions. However, the location(s) of the isotope fractionation is not clear yet and it is uncertain whether deuterium fractionation appears in other natural environments. In this study, through two extensive field campaigns utilizing a common dryland riparian tree species Populus euphratica Oliv., we showed that no significant δ(18) O differences were found between water source and various plant components, in accord with previous studies. We also found that no deuterium fractionation occurred during P. euphratica water uptake by comparing the deuterium composition (δD) of groundwater and xylem sap. However, remarkable δD differences (up to 26.4‰) between xylem sap and twig water, root water and core water provided direct evidence that deuterium fractionation occurred between xylem sap and root or stem tissue water. This study indicates that deuterium fractionation could be a common phenomenon in drylands, which has important implications in plant water source identification, palaeoclimate reconstruction based on wood cellulose and evapotranspiration partitioning using δD of stem water.
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Affiliation(s)
- Liangju Zhao
- College of Urban and Environmental Sciences, Northwest University, Xi'an, 710069, China
- Key Laboratory of Ecohydrology and Integrated River Basin Science, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - Lixin Wang
- Department of Earth Sciences, Indiana University-Purdue University Indianapolis (IUPUI), Indianapolis, IN, 46202, USA
| | - Lucas A Cernusak
- College of Marine and Environmental Sciences, James Cook University, Cairns, Queensland, Australia
| | - Xiaohong Liu
- State Key Laboratory of Cryospheric Sciences, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - Honglang Xiao
- Key Laboratory of Ecohydrology and Integrated River Basin Science, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - Maoxian Zhou
- School of Agriculture and Forestry Economics and Management, Lanzhou University of Finance and Economics, Lanzhou, 730101, China
| | - Shiqiang Zhang
- College of Urban and Environmental Sciences, Northwest University, Xi'an, 710069, China
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49
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Song X, Barbour MM. Leaf water oxygen isotope measurement by direct equilibration. New Phytol 2016; 211:1120-1128. [PMID: 27147584 DOI: 10.1111/nph.13962] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Accepted: 03/07/2016] [Indexed: 06/05/2023]
Abstract
The oxygen isotope composition of leaf water imparts a signal to a range of molecules in the atmosphere and biosphere, but has been notoriously difficult to measure in studies requiring a large number of samples as a consequence of the labour-intensive extraction step. We tested a method of direct equilibration of water in fresh leaf samples with CO2 , and subsequent oxygen isotope analysis on an optical spectrometer. The oxygen isotope composition of leaf water measured by the direct equilibration technique was strongly linearly related to that of cryogenically extracted leaf water in paired samples for a wide range of species with differing anatomy, with an R(2) of 0.95. The somewhat more enriched values produced by the direct equilibration method may reflect lack of full equilibration with unenriched water in the vascular bundles, but the strong relationship across a wide range of species suggests that this difference can be adequately corrected for using a simple linear relationship.
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Affiliation(s)
- Xin Song
- Centre for Carbon, Water and Food, The University of Sydney, 380 Werombi Road, Brownlow Hill, NSW, 2570, Australia
| | - Margaret M Barbour
- Centre for Carbon, Water and Food, The University of Sydney, 380 Werombi Road, Brownlow Hill, NSW, 2570, Australia
- Landcare Research, PO Box 40, Lincoln, 7640, New Zealand
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50
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Cernusak LA, Barbour MM, Arndt SK, Cheesman AW, English NB, Feild TS, Helliker BR, Holloway-Phillips MM, Holtum JAM, Kahmen A, McInerney FA, Munksgaard NC, Simonin KA, Song X, Stuart-Williams H, West JB, Farquhar GD. Stable isotopes in leaf water of terrestrial plants. Plant Cell Environ 2016; 39:1087-102. [PMID: 26715126 DOI: 10.1111/pce.12703] [Citation(s) in RCA: 106] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Revised: 11/21/2015] [Accepted: 12/16/2015] [Indexed: 05/14/2023]
Abstract
Leaf water contains naturally occurring stable isotopes of oxygen and hydrogen in abundances that vary spatially and temporally. When sufficiently understood, these can be harnessed for a wide range of applications. Here, we review the current state of knowledge of stable isotope enrichment of leaf water, and its relevance for isotopic signals incorporated into plant organic matter and atmospheric gases. Models describing evaporative enrichment of leaf water have become increasingly complex over time, reflecting enhanced spatial and temporal resolution. We recommend that practitioners choose a model with a level of complexity suited to their application, and provide guidance. At the same time, there exists some lingering uncertainty about the biophysical processes relevant to patterns of isotopic enrichment in leaf water. An important goal for future research is to link observed variations in isotopic composition to specific anatomical and physiological features of leaves that reflect differences in hydraulic design. New measurement techniques are developing rapidly, enabling determinations of both transpired and leaf water δ(18) O and δ(2) H to be made more easily and at higher temporal resolution than previously possible. We expect these technological advances to spur new developments in our understanding of patterns of stable isotope fractionation in leaf water.
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Affiliation(s)
- Lucas A Cernusak
- College of Marine and Environmental Sciences, James Cook University, Cairns, Australia
| | - Margaret M Barbour
- Centre for Carbon, Water and Food, Faculty of Agriculture and Environment, The University of Sydney, Camden, Australia
| | - Stefan K Arndt
- School of Ecosystem and Forest Sciences, The University of Melbourne, Richmond, Australia
| | - Alexander W Cheesman
- College of Marine and Environmental Sciences, James Cook University, Cairns, Australia
| | - Nathan B English
- College of Marine and Environmental Sciences, James Cook University, Townsville, Australia
| | - Taylor S Feild
- College of Marine and Environmental Sciences, James Cook University, Townsville, Australia
| | - Brent R Helliker
- Department of Biology, University of Pennsylvania, Philadelphia, USA
| | | | - Joseph A M Holtum
- College of Marine and Environmental Sciences, James Cook University, Townsville, Australia
| | - Ansgar Kahmen
- Department of Environmental Sciences-Botany, University of Basel, Basel, Switzerland
| | | | - Niels C Munksgaard
- College of Science, Technology and Engineering, James Cook University, Cairns, Australia
- Research Institute for the Environment and Livelihoods, Charles Darwin University, Darwin, Australia
| | - Kevin A Simonin
- Department of Biology, San Francisco State University, San Francisco, USA
| | - Xin Song
- Centre for Carbon, Water and Food, Faculty of Agriculture and Environment, The University of Sydney, Camden, Australia
| | | | - Jason B West
- Department of Ecosystem Science and Management, Texas A&M University, College Station, USA
| | - Graham D Farquhar
- Research School of Biology, The Australian National University, Canberra, Australia
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