USA CERL                                                                                                                          GMSLab

  Using Soil Erosion Modeling for Improved Conservation Planning: 
A GIS-based Tutorial

Models:

Computing USPED using GIS

 

We assume that we can estimate sediment flow at sediment transport capacity as

 

T = R K C P Am (sin b)n

 where R~im, KCP~Kt and LS=Am sin b n (add units here), and m=1.6, n=1.3 for prevailing rill erosion while m=n=1 for prevailing sheet erosion. Then the net erosion/deposition is estimated as

 

ED  =  div (T . s)  =  d(T*cos a)/dx  +  d(T*sin a)/dy

where a [deg] is aspect of the terrain surface.

The model is simple enough to be run as a sequence of commands provided here for
     ArcView3.2,
     ArcGIS8.1,
     GRASS5.

For routine applications the model can be run as a script, using Avenue in ArcView, Visual basic in ArcGIS8, and tcl/tk or UNIX scripting in GRASS.

HOME                                                        H. Mitasova, et al.,  Geographic Modeling Systems Lab, UIUC