This is an example of a multi-factor analysis. It is
our intention to demonstrate how the data can be interrogated
to answer specific questions below the 6th field watershed
level. This example will select sites at the stream reach
level. We are asking the GIS, in this example, to locate
confined,
moderate gradient
streams (streams with gradients 1.75 to 8.75% or 1.0
to 5.0 degrees).
This analysis was accomplished by doing a series of selections
in ARCView and then using the Geoprocessing Wizard to
clip the stream layer so that only the stream segments
meeting all of these criteria were selected.
Step 1: Using the derived stream
gradient layer, we used the query tool to select stream
segments that had a stream gradient ranging from 1-5 degrees.
Step 2: We then intersected these
moderate gradient streams with the confinement layer to
select moderate gradient, confined stream segments.
This analysis identified areas that
are potential winter steelhead habitat.
Please address questions or comments
to:
Dr. Ralph Garono
Principal Investigator
Earth Design Consultants, Inc.
rgarono@earthdesign.com
Laura Brophy
Principal Investigator
Green Point Consulting
brophyl@peak.org |
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