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San-Emeterio L, Zavala LM, Jiménez-Morillo NT, Pérez-Ramos IM, González-Pérez JA. Effects of Climate Change on Soil Organic Matter C and H Isotope Composition in a Mediterranean Savannah ( Dehesa): An Assessment Using Py-CSIA. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:13851-13862. [PMID: 37682017 PMCID: PMC10515479 DOI: 10.1021/acs.est.3c01816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 08/18/2023] [Accepted: 08/19/2023] [Indexed: 09/09/2023]
Abstract
Dehesas are Mediterranean agro-sylvo-pastoral systems sensitive to climate change. Extreme climate conditions forecasted for Mediterranean areas may change soil C turnover, which is of relevance for soil biogeochemistry modeling. The effect of climate change on soil organic matter (SOM) is investigated in a field experiment mimicking environmental conditions of global change scenarios (soil temperature increase, +2-3 °C, W; rainfall exclusion, 30%, D; a combination of both, W+D). Pyrolysis-compound-specific isotope analysis (Py-CSIA) is used for C and H isotope characterization of SOM compounds and to forecast trends exerted by the induced climate shift. After 2.5 years, significant δ13C and δ2H isotopic enrichments were detected. Observed short- and mid-chain n-alkane δ13C shifts point to an increased microbial SOM reworking in the W treatment; a 2H enrichment of up to 40‰ of lignin methoxyphenols was found when combining W+D treatments under the tree canopy, probably related to H fractionation due to increased soil water evapotranspiration. Our findings indicate that the effect of the tree canopy drives SOM dynamics in dehesas and that, in the short term, foreseen climate change scenarios will exert changes in the SOM dynamics comprising the biogeochemical C and H cycles.
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Affiliation(s)
- Layla
M. San-Emeterio
- Instituto
de Recursos Naturales y Agrobiología de Sevilla, Consejo Superior de Investigaciones Científicas
(IRNAS-CSIC), Av. Reina
Mercedes 10, 41012 Sevilla, Spain
- Universidad
de Sevilla, MED Soil Res. Group,
Dpt. Cristalografía, Mineralogía y Química Agrícola,
Facultad de Química, C/Prof Garcia Gonzalez 1, 41012 Sevilla, Spain
| | - Lorena M. Zavala
- Universidad
de Sevilla, MED Soil Res. Group,
Dpt. Cristalografía, Mineralogía y Química Agrícola,
Facultad de Química, C/Prof Garcia Gonzalez 1, 41012 Sevilla, Spain
| | - Nicasio T. Jiménez-Morillo
- Instituto
de Recursos Naturales y Agrobiología de Sevilla, Consejo Superior de Investigaciones Científicas
(IRNAS-CSIC), Av. Reina
Mercedes 10, 41012 Sevilla, Spain
- University
of Évora, Instituto Mediterrâneo
para a Agricultura, Ambiente e Desenvolvimento (MED), Núcleo da Mitra, Ap. 94, 7006-554 Évora, Portugal
| | - Ignacio M. Pérez-Ramos
- Instituto
de Recursos Naturales y Agrobiología de Sevilla, Consejo Superior de Investigaciones Científicas
(IRNAS-CSIC), Av. Reina
Mercedes 10, 41012 Sevilla, Spain
| | - José A. González-Pérez
- Instituto
de Recursos Naturales y Agrobiología de Sevilla, Consejo Superior de Investigaciones Científicas
(IRNAS-CSIC), Av. Reina
Mercedes 10, 41012 Sevilla, Spain
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Liu H, Wang S, Wang H, Cao Y, Hu J, Liu W. Apparent fractionation of hydrogen isotope from precipitation to leaf wax n-alkanes from natural environments and manipulation experiments. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 877:162970. [PMID: 36958560 DOI: 10.1016/j.scitotenv.2023.162970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 03/16/2023] [Accepted: 03/16/2023] [Indexed: 05/06/2023]
Abstract
Knowledge of hydrogen isotopic fractionation (ε) of plant leaf waxes is the foundation for applying hydrogen isotope values (δ2H) in environmental reconstructions. In this work, we systematically investigated plant ε values (εalk/precipitation, εalk/soil water, εalk/leaf water and εalk/lake water, representing the isotopic fractionation between plant n-alkane δ2H and precipitation δ2H, soil water δ2H, leaf water δ2H and lake water δ2H) from the natural environments and manipulation experiments. The results show that the εalk/precipitation values of terrestrial plants have large variations (from -190 ‰ to -20 ‰) and become more negative with increasing aridity index. This phenomenon is possibly caused by the δ2H changes in source water (from precipitation to soil water and then to leaf water) during plant leaf wax synthesis under various evapotranspiration conditions in different climatic zones. The rainfall manipulation experiments show that leaf water δ2H values are generally higher than soil water δ2H values, and the latter are higher than precipitation δ2H values. This finding further demonstrates that the evapotranspiration effect on source water δ2H affects the quantification of the leaf wax apparent ε values (εalk/leaf water < εalk/soil water < εalk/precipitation). The εalk/lake water values of submerged plants display a smaller range (-153 ± 5 ‰) than the εalk/precipitation values of terrestrial plants, which is close to the terrestrial εalk/precipitation values in humid areas. Therefore, the biosynthetic ε value of terrestrial plant leaf waxes is relatively constant (ca. -153 ± 5 ‰), and the observed variable apparent εalk/precipitation values are possibly caused by the varied degree of evapotranspiration effect on the water that plants used in different climatic conditions. This effect should be considered when applying δ2H values of leaf waxes to trace environmental changes.
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Affiliation(s)
- Hu Liu
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China; Xi'an Institute for Innovative Earth Environment Research, Xi'an 710061, China; CAS Center for Excellence in Quaternary Science and Global Change, Xi'an 710061, China
| | - Sizhuang Wang
- CAS Key Laboratory of Crust-Mantle Materials and the Environment, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China
| | - Huanye Wang
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China; CAS Center for Excellence in Quaternary Science and Global Change, Xi'an 710061, China
| | - Yunning Cao
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China; CAS Center for Excellence in Quaternary Science and Global Change, Xi'an 710061, China
| | - Jing Hu
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China; CAS Center for Excellence in Quaternary Science and Global Change, Xi'an 710061, China
| | - Weiguo Liu
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China; CAS Center for Excellence in Quaternary Science and Global Change, Xi'an 710061, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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3
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Hirave P, Nelson DB, Glendell M, Alewell C. Land-use-based freshwater sediment source fingerprinting using hydrogen isotope compositions of long-chain fatty acids. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 875:162638. [PMID: 36894091 DOI: 10.1016/j.scitotenv.2023.162638] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 03/01/2023] [Accepted: 03/01/2023] [Indexed: 06/18/2023]
Abstract
Rapidly changing land use patterns and frequent extreme weather events have resulted in an increased sediment flux to freshwater systems globally, highlighting the need for land-use-based sediment source fingerprinting. Application of variability in hydrogen isotope compositions (δ2H values) of vegetation-specific biomarkers from soils and sediments is relatively underexplored for land-use-based freshwater suspended sediment (SS) source fingerprinting, but has the potential to complement the information from routinely applied carbon isotope analysis and provide new insights. We analysed δ2H values of long-chain fatty acids (LCFAs) as vegetation-specific biomarkers in source soils and SS collected from the mixed land use Tarland catchment (74 km2) in NE Scotland, to identify stream SS sources and quantify their contributions to SS. Plant growth form was the primary control on source soils LCFAs (n-C26:0, n-C28:0, n-C30:0) δ2H variability, while the isotopic composition of source water had no significant control. Forest and heather moorland soils covered with dicotyledonous and gymnosperm species were differentiated from arable land and grasslands soils covered with monocotyledonous species. SS samples collected for fourteen months from the Tarland catchment with a nested sampling approach showed monocot-based land use (cereal crops, grassland) to be the major source of SS with 71 ± 11% contribution on catchment-wide scale averaged throughout the sampling period. Storm events after a dry summer period and sustained high flow conditions in the streams during autumn and early winter suggested enhanced connectivity of more distant forest and heather moorland land uses covering relatively steep topography. This was shown by an increased contribution (44 ± 8%) on catchment-wide scale from dicot and gymnosperm-based land uses during the corresponding period. Our study demonstrated successful application of vegetation-specificity in δ2H values of LCFAs for land-use-based freshwater SS source fingerprinting in a mesoscale catchment where δ2H values of LCFAs were primarily controlled by plant growth forms.
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Affiliation(s)
- Pranav Hirave
- Environmental Geosciences, Department of Environmental Sciences, University of Basel, 4056 Basel, Switzerland.
| | - Daniel B Nelson
- Department of Environmental Sciences - Botany, University of Basel, 4056 Basel, Switzerland
| | - Miriam Glendell
- The James Hutton Institute, Environmental and Biochemical Sciences Department, Craigiebuckler, Aberdeen AB15 8QH, United Kingdom
| | - Christine Alewell
- Environmental Geosciences, Department of Environmental Sciences, University of Basel, 4056 Basel, Switzerland
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4
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Cueni F, Nelson DB, Lehmann MM, Boner M, Kahmen A. Constraining parameter uncertainty for predicting oxygen and hydrogen isotope values in fruit. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:5016-5032. [PMID: 35512408 DOI: 10.1093/jxb/erac180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Accepted: 05/04/2022] [Indexed: 06/14/2023]
Abstract
Understanding δ18O and δ2H values of agricultural products like fruit is of particular scientific interest in plant physiology, ecology, and forensic studies. Applications of mechanistic stable isotope models to predict δ18O and δ2H values of water and organic compounds in fruit, however, are hindered by a lack of empirical parameterizations and validations. We addressed this lack of data by experimentally evaluating model parameter values required to model δ18O and δ2H values of water and organic compounds in berries and leaves from strawberry and raspberry plants grown at different relative humidities. Our study revealed substantial differences between leaf and berry isotope values, consistent across the different relative humidity treatments. We demonstrated that existing isotope models can reproduce water and organic δ18O and δ2H values for leaves and berries. Yet, these simulations require organ-specific model parameterization to accurately predict δ18O and δ2H values of leaf and berry tissue and water pools. We quantified these organ-specific model parameters for both species and relative humidity conditions. Depending on the required model accuracy, species- and environment-specific model parameters may be justified. The parameter values determined in this study thus facilitate applications of stable isotope models where understanding δ18O and δ2H values of fruit is of scientific interest.
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Affiliation(s)
- Florian Cueni
- University of Basel, Department of Environmental Sciences - Botany, Schönbeinstrasse 6, 4056 Basel, Switzerland
- Agroisolab GmbH, Professor-Rehm-Strasse 6, 52428 Jülich, Germany
| | - Daniel B Nelson
- University of Basel, Department of Environmental Sciences - Botany, Schönbeinstrasse 6, 4056 Basel, Switzerland
| | - Marco M Lehmann
- Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
| | - Markus Boner
- Agroisolab GmbH, Professor-Rehm-Strasse 6, 52428 Jülich, Germany
| | - Ansgar Kahmen
- University of Basel, Department of Environmental Sciences - Botany, Schönbeinstrasse 6, 4056 Basel, Switzerland
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5
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Fiorella RP, Kannenberg SA, Anderegg WRL, Monson RK, Ehleringer JR. Heterogeneous isotope effects decouple conifer leaf and branch sugar δ 18O and δ 13C. Oecologia 2022; 198:357-370. [PMID: 35107645 DOI: 10.1007/s00442-022-05121-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Accepted: 01/21/2022] [Indexed: 10/19/2022]
Abstract
Isotope ratios of tree-ring cellulose are a prominent tool to reconstruct paleoclimate and plant responses to environmental variation. Current models for cellulose isotope ratios assume a transfer of the environmental signals recorded in bulk leaf water to carbohydrates and ultimately into stem cellulose. However, the isotopic signal of carbohydrates exported from leaf to branch may deviate from mean leaf values if spatial heterogeneity in isotope ratios exists in the leaf. We tested whether the isotopic heterogeneity previously observed along the length of a ponderosa pine (Pinus ponderosa) leaf water was preserved in photosynthetic products. We observed an increase in both sugar and bulk tissue δ18O values along the needle, but the increase in carbohydrate δ18O values was dampened relative to the trend observed in leaf water. In contrast, δ13C values of both sugar and bulk organic matter were invariant along the needle. Phloem-exported sugar measured in the branch below the needles did not match whole-needle values of δ18O or δ13C. Instead, there was a near-constant offset observed between the branch and needle sugar δ13C values, while branch δ18O values were most similar to δ18O values observed for sugar at the base of the needle. The observed offset between the branch and needle sugar δ18O values likely arises from partial isotope oxygen exchange between sugars and water during phloem loading and transport. An improved understanding of the conditions producing differential δ13C and δ18O isotope effects between branch phloem and needle sugars could improve tree-ring-based climate reconstructions.
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Affiliation(s)
- Richard P Fiorella
- Department of Geology and Geophysics, University of Utah, Salt Lake City, UT, 84112, USA.
- Global Change and Sustainability Center, University of Utah, Salt Lake City, UT, 84112, USA.
- Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA.
| | - Steven A Kannenberg
- School of Biological Sciences, University of Utah, Salt Lake City, UT, 84112, USA
| | - William R L Anderegg
- Global Change and Sustainability Center, University of Utah, Salt Lake City, UT, 84112, USA
- School of Biological Sciences, University of Utah, Salt Lake City, UT, 84112, USA
| | - Russell 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
| | - James R Ehleringer
- Global Change and Sustainability Center, University of Utah, Salt Lake City, UT, 84112, USA
- School of Biological Sciences, University of Utah, Salt Lake City, UT, 84112, USA
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6
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Connolly R, Jambrina-Enríquez M, Herrera-Herrera AV, Mallol C. Investigating Hydrogen Isotope Variation during Heating of n-Alkanes under Limited Oxygen Conditions: Implications for Palaeoclimate Reconstruction in Archaeological Settings. Molecules 2021; 26:molecules26071830. [PMID: 33805066 PMCID: PMC8037755 DOI: 10.3390/molecules26071830] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 03/20/2021] [Accepted: 03/21/2021] [Indexed: 11/16/2022] Open
Abstract
This paper reports on a series of heating experiments that focus on n-alkanes extracted from leaf, bark, and xylem tissues of the Celtis australis plant. These lipid biomarkers were analysed for their compound-specific hydrogen isotopic composition (δ2Hwax) under limited oxygen conditions at 150, 250, 350, and 450 °C. Our results reveal isotopic variations in wax lipids of different plant organs during short-term low-temperature combustion. We conclude that, in the absence of a detailed characterisation of the depositional environment in advance of sampling, δ2Hwax values in archaeological or otherwise highly anthropogenic environments should be interpreted cautiously. In addition, we observed that variation in δ2Hwax of leaves is minimal at temperatures ≤ 350 °C, highlighting the potential for δ2Hwax in thermally altered combustion substrates to yield palaeoclimate information, which could allow researchers to investigate links between archaeological and climatic records at a high spatial and temporal resolution.
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Affiliation(s)
- Rory Connolly
- Instituto Universitario de Bio-Organica Antonio Gonzalez (IUBO), Universidad de La Laguna, 38206 Canary Islands, Spain; (R.C.); (M.J.-E.); (A.V.H.-H.)
- Departmento de Geografia e Historia, Universidad de La Laguna, 38200 Canary Islands, Spain
| | - Margarita Jambrina-Enríquez
- Instituto Universitario de Bio-Organica Antonio Gonzalez (IUBO), Universidad de La Laguna, 38206 Canary Islands, Spain; (R.C.); (M.J.-E.); (A.V.H.-H.)
- Departamento de Biología Animal, Edafología y Geología, Facultad de Ciencias, Universidad de La Laguna, 38200 Canary Islands, Spain
| | - Antonio V. Herrera-Herrera
- Instituto Universitario de Bio-Organica Antonio Gonzalez (IUBO), Universidad de La Laguna, 38206 Canary Islands, Spain; (R.C.); (M.J.-E.); (A.V.H.-H.)
| | - Carolina Mallol
- Instituto Universitario de Bio-Organica Antonio Gonzalez (IUBO), Universidad de La Laguna, 38206 Canary Islands, Spain; (R.C.); (M.J.-E.); (A.V.H.-H.)
- Departmento de Geografia e Historia, Universidad de La Laguna, 38200 Canary Islands, Spain
- Interdisciplinary Center for Archaeology and the Evolution of Human Behaviour (ICArEHB), Universidade do Algarve, Campus de Gambelas, Edificio 1, 8005-139 Faro, Portugal
- Correspondence:
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Schirrmacher J, Andersen N, Schneider RR, Weinelt M. Fossil leaf wax hydrogen isotopes reveal variability of Atlantic and Mediterranean climate forcing on the southeast Iberian Peninsula between 6000 to 3000 cal. BP. PLoS One 2020; 15:e0243662. [PMID: 33362206 PMCID: PMC7757796 DOI: 10.1371/journal.pone.0243662] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 11/24/2020] [Indexed: 11/19/2022] Open
Abstract
Many recently published papers have investigated the spatial and temporal manifestation of the 4.2 ka BP climate event at regional and global scales. However, questions with regard to the potential drivers of the associated climate change remain open. Here, we investigate the interaction between Atlantic and Mediterranean climate forcing on the south-eastern Iberian Peninsula during the mid- to late Holocene using compound-specific hydrogen isotopes from fossil leaf waxes preserved in marine sediments. Variability of hydrogen isotope values in the study area is primarily related to changes in the precipitation source and indicates three phases of increased Mediterranean sourced precipitation from 5450 to 5350 cal. BP, from 5150 to 4300 cal. BP including a short-term interruption around 4800 cal. BP, and from 3400 to 3000 cal. BP interrupted around 3200 cal. BP. These phases are in good agreement with times of prevailing positive modes of the North Atlantic Oscillation (NAO) and reduced storm activity in the Western Mediterranean suggesting that the NAO was the dominant modulator of relative variability in precipitation sources. However, as previously suggested other modes such as the Western Mediterranean Oscillation (WeMO) may have altered this overall relationship. In this regard, a decrease in Mediterranean moisture source coincident with a rapid reduction in warm season precipitation during the 4.2 ka BP event at the south-eastern Iberian Peninsula might have been related to negative WeMO conditions.
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Affiliation(s)
- Julien Schirrmacher
- CRC1266, Christian-Albrechts University, Kiel, Germany
- Leibniz Laboratory for Radiometric Dating and Stable Isotope Research, Christian-Albrechts University, Kiel, Germany
- * E-mail:
| | - Nils Andersen
- Leibniz Laboratory for Radiometric Dating and Stable Isotope Research, Christian-Albrechts University, Kiel, Germany
| | - Ralph R. Schneider
- CRC1266, Christian-Albrechts University, Kiel, Germany
- Leibniz Laboratory for Radiometric Dating and Stable Isotope Research, Christian-Albrechts University, Kiel, Germany
- Institute of Geosciences, Christian-Albrechts University, Kiel, Germany
| | - Mara Weinelt
- CRC1266, Christian-Albrechts University, Kiel, Germany
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Strobel P, Haberzettl T, Bliedtner M, Struck J, Glaser B, Zech M, Zech R. The potential of δ 2H n-alkanes and δ 18O sugar for paleoclimate reconstruction - A regional calibration study for South Africa. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 716:137045. [PMID: 32059328 DOI: 10.1016/j.scitotenv.2020.137045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Revised: 01/28/2020] [Accepted: 01/30/2020] [Indexed: 06/10/2023]
Abstract
The hydrogen isotopic composition of leaf wax-derived n-alkanes (δ2Hn-alkanes) is a widely applied proxy for (paleo)climatic changes. It has been suggested that the coupling with the oxygen isotopic composition of hemicellulose-derived sugars (δ18Osugar) - an approach dubbed 'paleohygrometer' - might allow more robust and quantitative (paleo)hydrological reconstructions. However, the paleohygrometer remains to be evaluated and tested regionally. In this study, topsoil samples from South Africa, covering extensive environmental gradients, are analysed. δ2Hn-alkanes correlates significantly with the isotopic composition of precipitation (δ2Hp), whereas no significant correlation exists between δ18Osugar and δ18Op. The apparent fractionation (εapp) is the difference between δ2Hn-alkanes and δ2Hp (εapp 2H) and δ18Osugar and δ18Op (εapp 18O), respectively, and integrates i) isotopic enrichment due to soil water evaporation, ii) leaf (and xylem) water transpiration and iii) biosynthetic fractionation. We find no correlation of εapp 18O nor for εapp 2H with temperature, and no correlation of εapp 2H with potential evapotranspiration and an aridity index. By contrast, εapp 18O correlates significantly with both potential evapotranspiration and the aridity index. This highlights the strong effect of evapotranspirative enrichment on δ18Osugar. In study areas without plant predominance using Crassulacean Acid Metabolism (CAM), coupling δ18Osugar and δ2Hn-alkanes enables to reconstruct δ2Hp and δ18Op with an offset of Δδ2H = 6 ± 27‰ and Δδ18O = 0.8 ± 3.7‰, respectively, as well as relative humidity (RH) with an offset of ΔRH = 6 ± 17%. The paleohygrometer does, however, not work well for our study areas where CAM plants prevail (reconstructed δ18Op, δ2Hp and RH are off by 3.1‰, 27.2‰ and 31.7%). This probably reflects plant-specific (phenological) adaptations and/or post-photosynthetic exchange reactions related to CAM metabolism. Overall, our findings corroborate that δ2Hn-alkanes and δ18Osugar are valuable proxies, and the paleohygrometer is a promising approach for paleoclimate reconstructions in southern Africa.
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Affiliation(s)
- P Strobel
- Physical Geography, Institute of Geography, Friedrich Schiller University Jena, Jena, Germany.
| | - T Haberzettl
- Physical Geography, Institute of Geography and Geology, University of Greifswald, Germany
| | - M Bliedtner
- Physical Geography, Institute of Geography, Friedrich Schiller University Jena, Jena, Germany
| | - J Struck
- Physical Geography, Institute of Geography, Friedrich Schiller University Jena, Jena, Germany
| | - B Glaser
- Institute of Agronomy and Nutritional Sciences, Soil Biogeochemistry, Martin-Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - M Zech
- Physical Geography with focus on Paleoenvironmental Research, Institute of Geography, Dresden University of Technology, Dresden, Germany
| | - R Zech
- Physical Geography, Institute of Geography, Friedrich Schiller University Jena, Jena, Germany
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9
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Lehmann MM, Goldsmith GR, Mirande-Ney C, Weigt RB, Schönbeck L, Kahmen A, Gessler A, Siegwolf RTW, Saurer M. The 18 O-signal transfer from water vapour to leaf water and assimilates varies among plant species and growth forms. PLANT, CELL & ENVIRONMENT 2020; 43:510-523. [PMID: 31732962 DOI: 10.1111/pce.13682] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 11/11/2019] [Accepted: 11/14/2019] [Indexed: 06/10/2023]
Abstract
The 18 O signature of atmospheric water vapour (δ18 OV ) is known to be transferred via leaf water to assimilates. It remains, however, unclear how the 18 O-signal transfer differs among plant species and growth forms. We performed a 9-hr greenhouse fog experiment (relative humidity ≥ 98%) with 18 O-depleted water vapour (-106.7‰) on 140 plant species of eight different growth forms during daytime. We quantified the 18 O-signal transfer by calculating the mean residence time of O in leaf water (MRTLW ) and sugars (MRTSugars ) and related it to leaf traits and physiological drivers. MRTLW increased with leaf succulence and thickness, varying between 1.4 and 10.8 hr. MRTSugars was shorter in C3 and C4 plants than in crassulacean acid metabolism (CAM) plants and highly variable among species and growth forms; MRTSugars was shortest for grasses and aquatic plants, intermediate for broadleaf trees, shrubs, and herbs, and longest for conifers, epiphytes, and succulents. Sucrose was more sensitive to δ18 OV variations than other assimilates. Our comprehensive study shows that plant species and growth forms vary strongly in their sensitivity to δ18 OV variations, which is important for the interpretation of δ18 O values in plant organic material and compounds and thus for the reconstruction of climatic conditions and plant functional responses.
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Affiliation(s)
- Marco M Lehmann
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Birmensdorf, 8903, Switzerland
| | - Gregory R Goldsmith
- Schmid College of Science and Technology, Chapman University, Orange, CA, 92866
| | | | - Rosemarie B Weigt
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Birmensdorf, 8903, Switzerland
| | - Leonie Schönbeck
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Birmensdorf, 8903, Switzerland
| | - Ansgar Kahmen
- Department of Environmental Sciences-Botany, University of Basel, Basel, 4056, Switzerland
| | - Arthur Gessler
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Birmensdorf, 8903, Switzerland
| | - Rolf T W Siegwolf
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Birmensdorf, 8903, Switzerland
| | - Matthias Saurer
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Birmensdorf, 8903, Switzerland
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10
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Distinctions in heterotrophic and autotrophic-based metabolism as recorded in the hydrogen and carbon isotope ratios of normal alkanes. Oecologia 2018; 187:1053-1075. [DOI: 10.1007/s00442-018-4189-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2017] [Accepted: 06/05/2018] [Indexed: 10/28/2022]
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Cormier MA, Werner RA, Sauer PE, Gröcke DR, Leuenberger MC, Wieloch T, Schleucher J, Kahmen A. 2 H-fractionations during the biosynthesis of carbohydrates and lipids imprint a metabolic signal on the δ 2 H values of plant organic compounds. THE NEW PHYTOLOGIST 2018; 218:479-491. [PMID: 29460486 DOI: 10.1111/nph.15016] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Accepted: 12/23/2017] [Indexed: 06/08/2023]
Abstract
Hydrogen (H) isotope ratio (δ2 H) analyses of plant organic compounds have been applied to assess ecohydrological processes in the environment despite a large part of the δ2 H variability observed in plant compounds not being fully elucidated. We present a conceptual biochemical model based on empirical H isotope data that we generated in two complementary experiments that clarifies a large part of the unexplained variability in the δ2 H values of plant organic compounds. The experiments demonstrate that information recorded in the δ2 H values of plant organic compounds goes beyond hydrological signals and can also contain important information on the carbon and energy metabolism of plants. Our model explains where 2 H-fractionations occur in the biosynthesis of plant organic compounds and how these 2 H-fractionations are tightly coupled to a plant's carbon and energy metabolism. Our model also provides a mechanistic basis to introduce H isotopes in plant organic compounds as a new metabolic proxy for the carbon and energy metabolism of plants and ecosystems. Such a new metabolic proxy has the potential to be applied in a broad range of disciplines, including plant and ecosystem physiology, biogeochemistry and palaeoecology.
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Affiliation(s)
- Marc-André Cormier
- Department of Environmental Systems Science, ETH Zürich, Universitätstrasse 2, 8092, Zürich, Switzerland
- Department of Environmental Sciences - Botany, University of Basel, Schönbeinstrasse 6, 4056, Basel, Switzerland
| | - Roland A Werner
- Department of Environmental Systems Science, ETH Zürich, Universitätstrasse 2, 8092, Zürich, Switzerland
| | - Peter E Sauer
- Department of Geological Sciences, Indiana University, Bloomington, IN, 47405-1405, USA
| | - Darren R Gröcke
- Stable Isotope Biogeochemistry Laboratory, Science Laboratories, Durham University, South Road, Durham, DH1 3LE, UK
| | - Markus C Leuenberger
- Climate and Environmental Physics, Physics Institute and Oeschger Centre for Climate Change Research, University of Bern, Sidlerstrasse 5, 3012, Bern, Switzerland
| | - Thomas Wieloch
- Department of Medical Biochemistry and Biophysics, Umeå University, 901 87, Umeå, Sweden
| | - Jürgen Schleucher
- Department of Medical Biochemistry and Biophysics, Umeå University, 901 87, Umeå, Sweden
| | - Ansgar Kahmen
- Department of Environmental Sciences - Botany, University of Basel, Schönbeinstrasse 6, 4056, Basel, Switzerland
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Pedentchouk N, Turich C. Carbon and hydrogen isotopic compositions of n-alkanes as a tool in petroleum exploration. ACTA ACUST UNITED AC 2017. [DOI: 10.1144/sp468.1] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
AbstractCompound-specific isotope analysis (CSIA) of individual organic compounds is a powerful but underutilized tool in petroleum exploration. When integrated with other organic geochemical methodologies it can provide evidence of fluid histories including source, maturity, charge history and reservoir processes that can support field development planning and exploration efforts. The purpose of this chapter is to provide a review of the methodologies used for generating carbon and hydrogen isotope data for mid- and high-molecular-weight n-alkanes.We discuss the factors that control stable carbon and hydrogen isotope compositions of n-alkanes and related compounds in sedimentary and petroleum systems and review current and future applications of this methodology for petroleum exploration. We discuss basin-specific case studies that demonstrate the usefulness of CSIA either when addressing particular aspects of petroleum exploration (e.g. charge evaluation, source rock–oil correlation, and investigation of maturity and in-reservoir processes) or when this technique is used to corroborate interpretations from integrated petroleum systems analysis, providing unique insights which may not be revealed when using other methods. CSIA of n-alkanes and related n-alkyl structures can provide independent data to strengthen petroleum systems concepts from generation and expulsion of fluids from source rock, to charge history, connectivity, and in-reservoir processes.
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Affiliation(s)
- Nikolai Pedentchouk
- School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ, UK
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Lehmann MM, Gamarra B, Kahmen A, Siegwolf RTW, Saurer M. Oxygen isotope fractionations across individual leaf carbohydrates in grass and tree species. PLANT, CELL & ENVIRONMENT 2017; 40:1658-1670. [PMID: 28436078 DOI: 10.1111/pce.12974] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2016] [Revised: 04/12/2017] [Accepted: 04/14/2017] [Indexed: 06/07/2023]
Abstract
Almost no δ18 O data are available for leaf carbohydrates, leaving a gap in the understanding of the δ18 O relationship between leaf water and cellulose. We measured δ18 O values of bulk leaf water (δ18 OLW ) and individual leaf carbohydrates (e.g. fructose, glucose and sucrose) in grass and tree species and δ18 O of leaf cellulose in grasses. The grasses were grown under two relative humidity (rH) conditions. Sucrose was generally 18 O-enriched compared with hexoses across all species with an apparent biosynthetic fractionation factor (εbio ) of more than 27‰ relative to δ18 OLW , which might be explained by isotopic leaf water and sucrose synthesis gradients. δ18 OLW and δ18 O values of carbohydrates and cellulose in grasses were strongly related, indicating that the leaf water signal in carbohydrates was transferred to cellulose (εbio = 25.1‰). Interestingly, damping factor pex px , which reflects oxygen isotope exchange with less enriched water during cellulose synthesis, responded to rH conditions if modelled from δ18 OLW but not if modelled directly from δ18 O of individual carbohydrates. We conclude that δ18 OLW is not always a good substitute for δ18 O of synthesis water due to isotopic leaf water gradients. Thus, compound-specific δ18 O analyses of individual carbohydrates are helpful to better constrain (post-)photosynthetic isotope fractionation processes in plants.
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Affiliation(s)
- Marco M Lehmann
- Laboratory of Atmospheric Chemistry, Paul Scherrer Institute (PSI), Villigen, CH-5232, Switzerland
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, CH-8903, Switzerland
| | - Bruno Gamarra
- Institute of Agricultural Sciences, ETH Zurich, Zurich, CH-8092, Switzerland
| | - Ansgar Kahmen
- Department of Environmental Sciences - Botany, University of Basel, Basel, CH-4056, Switzerland
| | - Rolf T W Siegwolf
- Laboratory of Atmospheric Chemistry, Paul Scherrer Institute (PSI), Villigen, CH-5232, Switzerland
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, CH-8903, Switzerland
| | - Matthias Saurer
- Laboratory of Atmospheric Chemistry, Paul Scherrer Institute (PSI), Villigen, CH-5232, Switzerland
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, CH-8903, Switzerland
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Gamarra B, Kahmen A. Low secondary leaf wax n-alkane synthesis on fully mature leaves of C3 grasses grown at controlled environmental conditions and variable humidity. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2017; 31:218-226. [PMID: 27778411 DOI: 10.1002/rcm.7770] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Revised: 10/17/2016] [Accepted: 10/17/2016] [Indexed: 06/06/2023]
Abstract
RATIONALE Leaf wax n-alkanes are long-chained aliphatic compounds that are present in the cuticle of terrestrial plant leaves. Their δ2 H values are used for the reconstruction of past environments and for plant ecological investigations. The timing of n-alkane synthesis during leaf development and the rate of synthesis of secondary n-alkanes in fully matured leaves are still a matter of debate. METHODS Using a 2 H-labeling approach we estimated secondary leaf wax n-alkane synthesis rates in mature leaf blades of six C3 grass species grown in climate chambers under controlled environmental conditions. RESULTS We found that mature grass leaves continue the synthesis of leaf wax n-alkanes after leaf maturation. The rate of secondary n-alkanes synthesis was, however, relatively low and varied in response to atmospheric humidity and among species from 0.09 to 1.09% per day. CONCLUSIONS Our investigation provides new evidence on the timing of cuticular wax synthesis in grass leaves and indicates that the majority of n-alkanes are synthesized during the initial development of the leaf. Our study will improve the interpretation of leaf wax n-alkane δ2 H values in environmental and geological studies as it suggests that secondary synthesis of leaf wax n-alkanes in grass leaves contributes only slightly to the geological record. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
- Bruno Gamarra
- Department of Environmental Systems Sciences, ETH Zürich, Switzerland
- Department of Environmental Sciences - Botany, University of Basel, Switzerland
| | - Ansgar Kahmen
- Department of Environmental Sciences - Botany, University of Basel, Switzerland
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