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I was hoping I could get some help on how to extract information from a land use raster using polygons. I have a layer with 157 polygons and a land use raster with multiple land use categories for the whole region. I need to calculate the area for each land use type in each of the polygons (either the area or the number of pixels). I already extracted the land use information using my polygons as a mask, but I have been unable to get the counts/area for each land use category PER polygon.

I have tried all the zonal and extraction tools, but I either get pixel counts of each land use in the whole layer (not counts per polygon) or I get the overall area for each polygon without any detail on the area for each land use category per polygon.

Could someone point me in the right direction please?

  • So you can have multiple land-use type with in a single polygon? Also, does the land-use use unique values to distinguish between categories? – TsvGis Jun 8 '15 at 22:19
  • I don't think you will get what you're after using Zonal Stats, perhaps a tool like Combine help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#//… would be a bit better (you will need to convert your polygons to rasters, use your FID as the value cellsize and snap raster of the land use). – Michael Stimson Jun 8 '15 at 22:26
  • You've tried all of the zonal tools? Because it sounds like you're asking for Zonal Histogram. – Chris W Jun 8 '15 at 22:34
  • Just came across this site link titled "count number of raster cells of different values inside polygon fishnet". This site makes reference to Zonal Histogram as mentioned by @Chris W – TsvGis Jun 8 '15 at 22:41
  • Thank you all for your answers, it was actually "Tabulate area" the option that I needed, because it let me set up specific zones for both the raster and the polygon layer. You were right Chris, I had not exhausted all the zonal options :) – AnnK Jun 21 '15 at 15:33
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A thematic/categorical dataset such as landuse would technically be appropriate for a polygon feature class rather than a raster. So, one solution would be to convert your land use raster to a vector layer, and then perform a spatial join that would result in an attribute table with a record for each polygon--land use combination. Another option is to use the Intersect tool on the two polygon layers.

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