Observations of Runoff Generation During the Dry/Wet Seasonal Transition in Panama
Abstract
During 2005, the P.I. and graduate students installed an extensive network of instrumentation near Gamboa, Panama, for the purpose of making observations of hydrologic and hydrometeorological parameters at the hillslope scale. Instrumentation installed include an eddy-correlation flux system on a 36 m tall tower near Cerro Pelado, and throughfall troughs, soil moisture sensors, rain gages, interflow collector, piezometers, and surface flow measurement. Fundamental hypotheses were tested regarding changes in runoff efficiency during the early wet season. Results indicate that at the Gamboa study site, soil water hydrophobicity plays an important role early in the wet season. As the wet season advances, the role of hydrophobicity is diminished, while groundwater levels rise, increasing the occurrence of saturation excess runoff. During the most extreme rainfall event observed (150 mm of rainfall in 24 hours on Christmas Day, 2005), runoff occurred from upland areas likely due to mechanisms other than the traditional saturation excess runoff mechanism. These might include short-term perched water table due to high-intensity rainfall given the significant vertical change in hydraulic conductivities in the soils at Gamboa.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 31, 2005
- Accession Number
- ADA447367
Entities
People
- Fred L. Ogden
Organizations
- University of Connecticut