Using ground-penetrating radar to observe hidden underground water...( MADISON WI March 10 2008 -- To meet ...)

MADISON, WI, March 10, 2008 -- To meet the needs of a growing population and to provide it with a higher quality of life, increasing pressures are being placed on the environment through the development of agriculture, industry, and infrastructures.

Soil erosion, groundwater depletion, salinization, and pollution have been recognized for decades as major threats to ecosystems and human health. More recently, the progressive substitution of fossil fuels with biofuels for energy production have been recognized as potential threats to water resources and sustained agricultural productivity.

The top part of the earth between the surface and the water table is called the vadose zone. The vadose zone mediates many of the processes that govern water resources and quality, such as the partition of precipitation into infiltration and runoff, groundwater recharge, contaminant transport, plant growth, evaporation, and energy exchanges between the earths surface and its atmosphere. It also determines soil organic carbon sequestration and carbon-cycle feedbacks, which could substantially affect climate change.

The vadose zones inherent spatial variability and inaccessibility make direct observation of the important belowground (termed subsurface) processes difficult. Conventional soil sampling is destructive, laborious, expensive, and may not be representative of the actual variability over space and time. In a societal context where the development of sustainable and optimal environmental management strategies has become a priority, there is a strong prerequisite for the development of noninvasive characterization and monitoring techniques of the vadose zone.

In particular, approaches integrating water movement, geological, and physical principles (called hydrogeophysics) applied at relevant scales are required to appraise dynamic belowground phenomena and to develop optimal sustainability, exploitation, and remediation strategies.'/>"/>