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.
Original language | English |
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Pages (from-to) | 486-493 |
Number of pages | 8 |
Journal | Science of the Total Environment |
Volume | 595 |
Early online date | 2 May 2017 |
DOIs | |
Publication status | Published - 1 Oct 2017 |
Bibliographical note
We are thankful for the assistance of Audrey Innes (University of Aberdeen) and Kim Janzen (University of Saskatchewan) with soil and vegetation laboratory sample preparation and analyses. We would like to thank the European Research Council (ERC, project GA 335910 VeWa) for funding. The comments from two reviewers greatly improved an earlier version of the manuscript, for which we are highly grateful.Keywords
- vegetation water use
- soil water storage
- isotopes