HR: 11:20h
AN: H51F-05    [PDF]
TI: Channel Initiation on Slopes and Roads in a Tropical Montane Watershed in Northern Thailand
AU: Wood, S
EM: swood@boisestate.edu
AF: Department of Geosciences Boise State University, 1910 University Dr., Boise, ID 83725
AU: * McNamara, J P
EM: jmcnamar@boisestate.edu
AF: Department of Geosciences Boise State University, 1910 University Dr., Boise, ID 83725
AU: Ziegler, A
EM: adz@Princeton.EDU
AF: Geography National University Singapore, 1 Arts Link Kent Ridge, Singapore, 656777 Singapore
AB: The Pang Khum Experimental Watershed in Northern Thailand has been the site of ongoing hydrologic studies since 1997. Current efforts are focused on quantifying the impacts of agricultural practices versus new unpaved roads on sediment delivery to streams. To support this effort, we conducted a field survey of channel initiation mechanisms on hillslopes and roads in the watershed and modeled the boundaries of erosion regimes in slope-area space using a high resolution digital elevation model. Field results show that three channel initiation mechanisms operate in the watershed: 1) shallow landsliding, 2) erosion by overland flow, and 3) spring sapping. Locations susceptible to these processes plot in distinct fields on a graph of slope versus area, and channel heads on rods plot in yet another field. Further, channel heads formed by any of these mechanisms fall in a region on a slope area plot that separates channeled and unchanneled convergent topography.
DE: 1824 Geomorphology (1625)
SC: Hydrology [H]
MN: 2003 Fall Meeting