title: A simple pore water hydrogen diffusion syringe sampler.
abstract: Molecular hydrogen (H(2)) is an important intermediate product and electron donor in microbial metabolism. Concentrations of dissolved H(2) are often diagnostic of the predominant terminal electron-accepting processes in ground water systems or aquatic sediments. H(2) concentrations are routinely measured in ground water monitoring wells but are rarely measured in saturated aquatic sediments due to a lack of simple and practical sampling methods. This report describes the design and development (including laboratory and field testing) of a simple, syringe-based H(2) sampler in (1) saturated, riparian sediments, (2) surface water bed sediments, and (3) packed intervals of a fractured bedrock borehole that are inaccessible by standard pumped methods.
authors.affiliation: U.S. Geological Survey, 720 Gracern Road, Columbia, SC 29210-7651, USA. dvroblesk@usgs.gov
authors.forename: Don A
authors.initials: DA
authors.lastname: Vroblesky
authors.forename: Francis H
authors.initials: FH
authors.lastname: Chapelle
authors.forename: Paul M
authors.initials: PM
authors.lastname: Bradley
mesh_terms: D004058:Diffusion; D004784:Environmental Monitoring / Q000295:instrumentation* / Q000379:methods; D005618:Fresh Water / Q000032:analysis / Q000737:chemistry; D019015:Geologic Sediments / Q000032:analysis / Q000737:chemistry; D006859:Hydrogen / Q000032:analysis* / Q000737:chemistry; D015203:Reproducibility of Results; D013594:Syringes; D014867:Water / Q000032:analysis* / Q000737:chemistry
chemical_list: D014867:Water; D006859:Hydrogen