The role of atmospheric conditions in CO and radon emissions from an abandoned water well.

Boreholes and wells are complex boundary features at the earth-atmosphere interface, connecting the subsurface hydrosphere, lithosphere, and biosphere to the atmosphere above it. It is important to understand and quantify the air exchange rate of these features and, consequently their contribution as sources for greenhouse gas (GHG) emissions to the atmosphere. Here, we investigate the effect of atmospheric conditions, namely atmospheric pressure and temperature, on air, CO, and radon transport across the borehole-ambient atmosphere interface and inside a 110-m deep by 1-m diameter borehole in northern Israel.

Characterization of hydrophobic soils: a novel approach using mid-infrared photoacoustic spectroscopy.

Previous research has produced conclusive evidence to show that soil hydrophobicity is affected by soil organic matter (SOM) and soil water content (WC). Soil hydrophobicity that responds to WC is a unique form of hydrophobicity called reversible hydrophobicity. The mechanistic processes by which water and SOM interact continue to be a subject of investigation.

In situ separation of root hydraulic redistribution of soil water from liquid and vapor transport.

Nocturnal increases in water potential (ψ) and water content (θ) in the upper soil profile are often attributed to root water efflux, a process termed hydraulic redistribution (HR). However, unsaturated liquid or vapor flux of water between soil layers independent of roots also contributes to the daily recovery in θ (Δθ), confounding efforts to determine the actual magnitude of HR. We estimated liquid (J(l)) and vapor (J(v)) soil water fluxes and their impacts on quantifying HR in a seasonally dry ponderosa pine (Pinus ponderosa) forest by applying existing datasets of ψ, θ and temperature (T) to soil water transport equations.