Quantification of Habitat Disturbance
Within Small Watersheds
I used the ArcView Image Analyst to determine the amount of disturbed habitat within each watershed
First, an aerial photograph was imported into ArcView and Georeferenced to the delineated watersheds
Next, Image Analyst was used to categorize the habitats present in the photograph into five categories, the resulting image was smoothed three times to simplify the areas.
The categorized image was converted to a shapefile and clipped by the watersheds calculated with the BASIN script
When compared to the aerial photograph, it was evident that categories colored yellow and gray represented disturbed habitats. These habitats typically consisted of roads and other impervious surfaces, cleared land, and houses. The XTools script was then used to calculate the percentage of each watershed covered by each habitat category. These percentages were later compared to the relative abundance of salamanders from each stream.
3D views of one of the watersheds generated using ArcView 3D Analyst. Watersheds were deliniated with BASIN and habitats categorized using ArcView Image Analyst. Shades of Green represent forested areas while yellow and greay categories represent disturbed habitats.
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