By the same authors

From the same journal

Understanding 2H/1H systematics of leaf wax n-alkanes in coastal plants at Stiffkey saltmarsh, Norfolk, UK

Research output: Contribution to journalArticle

Published copy (DOI)

Author(s)

  • Yvette Eley
  • Lorna Dawson
  • Stuart Black
  • Julian Andrews
  • Nikolai Pedentchouk

Department/unit(s)

Publication details

JournalGeochimica et Cosmochimica Acta
DateE-pub ahead of print - 15 Dec 2013
DatePublished (current) - 1 Mar 2014
Volume128
Number of pages16
Pages (from-to)13-28
Early online date15/12/13
Original languageEnglish

Abstract

Interpretation of sedimentary n-alkyl lipid δ2H data is complicated by a limited understanding of factors controlling interspecies variation in biomarker 2H/1H composition. To distinguish between the effects of interrelated environmental, physical and biochemical controls on the hydrogen isotope composition of n-alkyl lipids, we conducted linked δ2H analyses of soil water, xylem water, leaf water and n-alkanes from a range of C3 and C4 plants growing at a UK saltmarsh (i) across multiple sampling sites, (ii) throughout the 2012 growing season, and (iii) at different times of the day. Soil waters varied isotopically by up to 35‰ depending on marsh sub-environment, and exhibited site-specific seasonal shifts in δ2H up to a maximum of 31‰. Maximum interspecies variation in xylem water was 38‰, while leaf waters differed seasonally by a maximum of 29‰. Leaf wax n-alkane 2H/1H, however, consistently varied by over 100‰ throughout the 2012 growing season, resulting in an interspecies range in the εwax/leaf water values of -79 to -227‰. From the discrepancy in the magnitude of these isotopic differences, we conclude that mechanisms driving variation in the 2H/1H composition of leaf water, including (i) spatial changes in soil water 2H/1H, (ii) temporal changes in soil water 2H/1H, (iii) differences in xylem water 2H/1H, and (iv) differences in leaf water evaporative 2H-enrichment due to varied plant life forms, cannot explain the range of n-alkane δ2H values we observed. Results from this study suggests that accurate reconstructions of palaeoclimate regimes from sedimentary n-alkane δ2H require further research to constrain those biological mechanisms influencing species-specific differences in 2H/1H fractionation during lipid biosynthesis, in particular where plants have developed biochemical adaptations to water-stressed conditions. Understanding how these mechanisms interact with environmental conditions will be crucial to ensure accurate interpretation of hydrogen isotope signals from the geological record.

    Research areas

  • stable isotopes, leaf wax biomarkers, palaeoclimate, palaeohydrology

Discover related content

Find related publications, people, projects, datasets and more using interactive charts.

View graph of relations