Soil and Topographic Influences On Spatiotemporal Patterns of Saturated Zones.

Understanding when and where saturated zones occur on the landscape is required to implement site-specific management strategies for reducing runoff of agricultural nutrients.  The high cost to purchase, install, and maintain soil moisture sensors or water table monitoring equipment is a limitation for high-resolution spatial information on saturated zones.  Portable, electromagnetic induction instruments allow for the rapid acquisition of apparent electrical conductivity (ECa) data, which (assuming uniform soil properties and salt content) indicates changes in soil moisture.  In this study, an electromagnetic induction instrument was used to collect georeferenced-ECa data over a hillslope in Rock Springs, Pennsylvania after a storm event on April 19, 2013.  The role of soil properties and restrictive layers on saturated regions of the hillslope will be evaluated via pit descriptions, soil cores, and the use of ground penetrating radar (GPR).  Topographic parameters (e.g. slope, curvature) and wetness indices will be modeled for the hillslope using both surface and subsurface DEMs, obtained from LIDAR and GPR data, respectively.