Lee MacDonald
Professor
Dept. of Forest, Rangeland, and Watershed Stewardship
Warner College of Natural Resources
Colorado State University
Fort Collins, CO 80523-1472
Colorado State University
Fort Collins, CO 80523-1472
Phone: (970) 491-6109
Office: 328 Natural Resources Bldg.
leemac@cnr.colostate.edu
Delta-Q and FOREST
Cumulative Effects Models:
Recent increases in geographic information
systems, computing power, and field data are facilitating the development
of spatially explicit, quasi-physically based models to more accurately
assess cumulative watershed effects (CWEs). The goal is to develop
a modular set of procedures that allows resource specialists to rapidly
predict changes in runoff and sediment yields for watersheds ranging in
size from approximately 10 to 100 km2.
As a first step, two modules are being developed to predict catchment-scale changes in runoff and surface erosion due to forest harvest, roads, and fires. With respect to runoff, the lack of paired-watershed studies in the Sierra means that management-induced changes in peak flows, median flows, and low flows are estimated from published values. Background and management-induced erosion rates are being obtained from a combination of literature values and field data collected by the authors from 1999-2002. The predicted changes in runoff are summed over the catchment being modeled, while the sediment model has procedures to deliver sediment from the hillslope to the stream network as a function of hillslope gradient, land cover, soils, and distance from the channel. Sediment will be routed through the stream network as a function of stream gradient, drainage area, and particle size.
As a first step, two modules are being developed to predict catchment-scale changes in runoff and surface erosion due to forest harvest, roads, and fires. With respect to runoff, the lack of paired-watershed studies in the Sierra means that management-induced changes in peak flows, median flows, and low flows are estimated from published values. Background and management-induced erosion rates are being obtained from a combination of literature values and field data collected by the authors from 1999-2002. The predicted changes in runoff are summed over the catchment being modeled, while the sediment model has procedures to deliver sediment from the hillslope to the stream network as a function of hillslope gradient, land cover, soils, and distance from the channel. Sediment will be routed through the stream network as a function of stream gradient, drainage area, and particle size.
(Post fire erosion - Schoonover Gulch, CO )
(Patch cuts - Coon Creek, WY)
Objective:
To develop a model with the following characteristics:- spatially explicit modules to predict changes in runoff and sediment generation
- a user-friendly model characterized by a sequential, menu-driven graphical user interface (GUI);
- a modular approach that can be updated and expanded with improved or alternative predictive algorithms;
- flexibility in allowing users to readily change input values.
