Abstract:
Water movement, from forest soil to streams, has traditionally been modeled by translatory flow. A hypothesis was presented by Brooks et al. (2010) suggesting that, in addition to translatory flow, there exists an immobile pool of water trapped in small pores with low matric potential. Comparisons of water stable isotope ratios between loosely-bound water and bulk soil water can provide additional evidence for this hypothesis. In this work the beginnings of a method for separating loosely-bound water from a soil core has been developed. It was found that, by centrifuging a soil core, sufficient water for mass spectrometry can be extracted at a given matric potential and held within a porous ceramic rod. This water can then be extracted from the ceramic using cryogenic vacuum distillation.
