Bark water affects the isotopic composition of xylem water in tropical rainforest trees

Frontiers in Forests and Global Change, Journal Year: 2025, Volume and Issue: 7

Published: Jan. 28, 2025

The movement of water between xylem and inner bark (phloem associated tissues), mostly driven by potential differences, forms a key part the diel transpiration cycle. It is not known how use stored in at cycle may influence isotopic composition water. Understanding these possible effects major challenge for identification tree sources interpretation patterns using isotopes. Here, we examined variation scale assessed this varied relation to traits strategies on nine species tropical rainforest end dry season. We measured δ 2 H 18 O two shallow depths: ‘outer xylem’ ‘inner (up ~0.5 cm ~ 1 from bark, respectively) collected predawn, morning midday. Considering all together, average outer was similar predawn midday, suggesting exchange tissues reflected times, but differed significantly during increased transpiration. Results suggest that bark-xylem throughout affects trees. Furthermore, variations were more pronounced deep-rooted, isohydric with dense wood than shallow-rooted, anisohydric low density. This differences related hydraulic reliance bark-stored across buffer changes potential. discuss implications interpreting strategies.

Language: Английский

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Hydrogen and triple-oxygen isotope effects of water adsorption on KGa-2 kaolinite with implications for pedological separation of soil water

Geochimica et Cosmochimica Acta, Journal Year: 2025, Volume and Issue: unknown

Published: April 1, 2025

Language: Английский

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Sub‐Daily Variations in Tree Xylem Water Isotopic Compositions in a Temperate Northeastern US Forest

Hydrological Processes, Journal Year: 2025, Volume and Issue: 39(4)

Published: April 1, 2025

ABSTRACT Sampling of stable isotopes in plant xylem water (δ 2 H, δ 18 O) has become a ubiquitous technique to study spatiotemporal variations the taken up by roots; however, open questions remain concerning most appropriate time day sample trees obtain representative isotopic values XYLEM ). We sampled oak and maple prior solar midday (i.e., recommended sampling window) then again after outside across 4 months. The paired root mean squared difference between AM PM O ranged from 1.00‰ 1.16‰ for maples 0.23‰ 2.55‰ oaks all dates. Xylem seasonal origin index (SOI) derived samples were significantly different, though both SOI estimates supported conclusion that reflected summer precipitation on conclude is significant consideration design campaigns; our findings also support flexibility collection field sites where during optimal challenging.

Language: Английский

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Comparative Analysis of Water Isotopic Compositions: Evaluating Isotope Analyzer for Soil and Extraction Method for Stem Water

Forests, Journal Year: 2024, Volume and Issue: 15(3), P. 420 - 420

Published: Feb. 22, 2024

Stable isotopes of water (δ2H and δ18O) are reliable tracers for the investigation plant–soil–water interactions in forest ecosystems. However, variations isotopic compositions may arise due to differences analytical instruments extraction methods. In this study, we conducted three different experiments identify caused by methodological variations. First, analyzed soil using two most commonly applied methods: isotope ratio mass spectrometry (IRMS) cavity ring-down spectroscopy (CRDS). Second, compared xylem extracted from stems nine tree species cryogenic vacuum distillation (CVD) with heating times. Third, mechanical squeezing a pressure chamber (PC), an induction module (IM), CVD. The composition between IRMS CRDS were significant but minimal. Soil properties not factors contributing instruments. For CVD, each required more than hours. Significant observed δ2H among methods water. Xylem CVD showed depleted values those obtained PC IM. Our results highlight importance considering stable analysis.

Language: Английский

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