HR: 1400h
AN: H53D-07    [Abstracts]
TI: Downslope Unsaturated Throughflow
AU: * Torres, R
EM: torres@geol.sc.edu
AF: University of South Carolina, Department of Geological Sciences 701 Sumter Street, EWS617, Colubmia, SC 29208, United States
AB: The hydrologic science community lacks a consensus on the role of lateral unsaturated throughflow in soil-water cycling. For example, some studies indicate that lateral unsaturated flow may contribute to stormflow, while others suggest this is not the case. Some analyses require soil heterogeneity for its occurrence and others do not. Some researchers indicate that lateral unsaturated flow may support baseflow while others report that it is not likely to contribute much flow at all. These disparate findings preclude the development of a conceptual model for the initiation and stability of lateral (also called downslope or slope parallel) unsaturated flow processes. This shortcoming is particularly acute given that lateral unsaturated flow is often invoked to explain the spatial and temporal variability in root zone soil-water dynamics, a critical facet of ecohydrology. Few studies, however, have addressed the temporal variability and controls on the development and stability of downslope unsaturated flow. Here we present data and analyses from the Coos Bay experiments that document the dynamics of unsaturated zone flow paths, we characterize the conditions necessary for its initiation, and we present estimates of annual downslope flux.
DE: 1860 Streamflow
DE: 1866 Soil moisture
DE: 1875 Vadose zone
SC: Hydrology [H]
MN: 2007 Joint Assembly