I have two polygon layers in a geodatabase. One layer is land parcels. The other layer is land use. I want to identify the six largest parcels that contain both "upland forests" and "wetlands" (i.e. WHERE landuse = 4 AND 6 in a single parcels). How do I proceed???
As an alternative to the first answer, this approach uses flag fields on the parcel layer to indicate if the parcel contains upland forest or wetlands:
- On the parcel layer, add integer fields "has_forest" and "has_wetland"
- Select (by attribute) the "upland forest" landuse features
- Select (by location) parcel features that intersect the selected landuse features
- Using field calculator, calculate has_forest = 1 on selected parcels
- Clear all selections
- Select (by attribute) the "wetland" landuse features (in steps 6-8 you're repeating steps 2-4 for wetlands)
- Select (by location) parcel features that intersect selected landuse features
- Using field calculator, calculate has_wetland = 1 on selected parcels
If you create a definition query to select features from parcels where has_forest = 1 AND has_wetland = 1, then your layer will only show parcels that contain both upland forest and wetlands. You can then sort on an area field and select the top 6. Once you've completed your analysis, you should probably remove the has_forest and has_wetland flags.
- Use Identity tool form toolbox(ArcToolbox => Analysis Tools => Overlay => Identity)
- Input your data . select Join Attributes option to All and run the tool
- open the attribute of the Identity result . you can summarize the parcel field(Right click to the Parcel name or code or... . click summarize and use it . find which parcels have Upland forests and wetlands.
- select them and calculate Area of the parcels. find six largest parcels