Current methods for stable oxygen isotopic (delta(18)O) analysis of soil water rely on separation of water from the soil matrix before analysis. These separation procedures are not only time consuming and require relatively large samples of soil, but also have been shown to introduce a large potential source of error. Current research at Queen's University Belfast is focused on using direct equilibration of CO2 with the pore water to eliminate this extraction step using the automated Multiprep system and a Micromass Prism III isotope ratio mass spectrometer (IRMS). The findings of this research indicate the method is less time consuming, more reliable, and reproducible to within accepted limits (+/-0.1%parts per thousand delta(18)O). In this study the direct equilibration method is used to analyse delta(18)O tracer profiles in the unsaturated zone of field soils, concurrently with chloride tracer profiles, which can be used to assess infiltration rates and mechanisms through the unsaturated zone. Copyright (C) 1999 John Wiley & Sons, Ltd.
|Number of pages||7|
|Journal||Rapid Communications in Mass Spectrometry|
|Publication status||Published - 15 Jul 1999|
- soil water
- soil matrix
- soil analysis
- chloride tracer profiles