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Environmental GIS. Nicholas A. Procopio, Ph.D, GISP nick@drexel.edu. Question?. Can we develop a measure of habitat integrity using land-cover data? What is the best way to evaluate this? What spatial tools will accommodate this analysis?. Spatial analysis toolbox.
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Environmental GIS Nicholas A. Procopio, Ph.D, GISP nick@drexel.edu
Question? • Can we develop a measure of habitat integrity using land-cover data? • What is the best way to evaluate this? • What spatial tools will accommodate this analysis? Spatial analysis toolbox
Spatial Analyses • Reclassify • Reclassifies (or changes) the values in a raster. • Reclass cover types as habitat (1) or nonhabitat (0)
Spatial Analyses • Focal Stat. • Calculates for each input cell location a statistic of the values within a specified neighborhood around it.
Sum all the pixels in a 1000 meter radius surrounding each pixel. • This value can than be normalized as a percentage of the maximum possible.
Intermediate steps… • Convert to float values. {Float} Converts each cell value of a raster into a floating-point representation. (continuous value to floating point values). • Recalculate as a percentage of window maximum. {Divide} • Window max = 100 pixels radius, pi*100^2 = 31417 pixels
Focal Statistic Output, as a percentage 100 habitat integrity? 0
X {times} 0/1 data Cell value habitat integrity less altered lands