A Look Underground

For Joe Sinfield, an assistant professor in civil engineering, the chance to quickly identify compounds underground is the driving force behind his desire to miniaturize laboratory equipment that can be taken straight to the fields.

Shown here in the lab with Oliver Colic, a graduate student in electrical and computer engineering, Sinfield is very much a cross-disciplinarian- working with agriculturists, engineers, and industry folk-pursuing the development of a real-time, mobile in situ sensing system capable of monitoring levels of compounds such as nitrogen and phosphorous in farmland effluent, animal wastes, and cultivated soils using optical spectroscopic techniques.

"Traditionally," he says, "to do this type of assessment, we'd collect field samples at a limited number of dispersed locations and perform in-laboratory analysis using a range of wet chemistry and bench-top spectroscopic techniques. That approach, however, is expensive, time-consuming, and limited in value due to the inherent spatial variability of the quantities under investigation and the limited amount of information gathered from the few samples that can be cost-effectively analyzed."

His work, utilizing recent advances in diode laser technology and fiber optics, promises real-time capabilities on site, providing greater spatial resolution and convenience at as little as one-tenth the cost.