Plant survey of current vegetation of Sonoran desert plant community distribution in mountain parks in central Arizona-Phoenix, August 1999.

This study represents an effort to map the distribution of plant community types
across the Central Arizona - Phoenix Long Term Ecological Research (CAP-LTER) site
centered in metropolitan Phoenix using Landsat ETM data. Vegetation classification
was carried out using field data collected from within the study area describing
woody plant species. A system was devised which represented a compromise between
providing floristic information and enabling maximum spectral discrimination between
community types. Image classification used reference spectra derived from training
sites in the field and was carried out on subsets defined by soil surface texture in
order to control for the strong background soil signature inherent to arid regions.
While groundtruthing revealed that vegetation on clayey soils was mapped to 91%
accuracy, other sections produced maps with less accuracy. The results of this study
demonstrate that image classification of desert vegetation using only Landsat ETM
data is problematic and may not be practical without other supporting data, such as
radar imaging.