Geomorphic modeling and routing improvements for GIS-based watershed assessment in arid regions.

Watershed models have two significant shortcomings that limit their application to management problems in arid and semi-arid regions. The first is that the performance of event-based hydrologic models for ephemeral stream networks declines significantly as watershed size increases. The second is that no single model is capable of simulating runoff, erosion, and geomorphic response in the channel network for multiple consecutive events. A diffusion-wave routing subroutine was developed for the Kinematic Runoff and Erosion Model (K_INEROS2) using a four-point iterative solution to the modified variable-parameter Muskingum-Cunge (MVPMC4) technique. It was tested against kinematic-wave routing at scales ranging from 0.05 to 150 km² on the Walnut Gulch Experimental Watershed in southeastern Arizona. Analyses demonstrated that MVPMC4 routing significantly improves simulated outflow hydrographs for small to moderate events on watersheds that are 95 km2 and larger. A geomorphic model was developed by modifying KINEROS2 to compute width, depth and slope adjustments from computed changes in sediment storage at each time step. Width and depth adjustments are determined by minimizing total stream power for each reach. A GIS-based interface was developed for model parameterization, coordinating multiple-event batch simulations, tracking cumulative geomorphic change, computing the sediment mass balance, visualizing results, and comparing results from different simulations.

Name thesis:degree_name

Ph. D.

Level thesis:degree_level

doctoral

Discipline thesis:degree_discipline

Renewable Natural Resources

Grantor dc:publisher

The University of Arizona.

Year dc:date.issued

2004

Author dc:creator

• Semmens, Darius James.

Committee members dc:contributor.committeemember

• Hawkins, Richard H.
• Lopes, Vicente
• Guertin, Philip
• Wissler, Craig
• Goodrich, David C.

• Hydrology.
• Watershed management -- Arizona.
• Arid regions.

Statement dc:rights

• Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.

Language dc:language.iso

en

Handle dc:identifier.uri

http://hdl.handle.net/10150/191267

OAI identifier oai:identifier

oai:repository.arizona.edu:10150/191267