Appendix 1 Processing steps

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There are six phases for creating the ecumene, using Microsoft® Access (Version 10.0) and ESRI® ArcGIS™ (Version 9.1) software.

Phase 1. Prepare ecumene master file and attribute data

  1. Import Statistics Canada's dissemination block (DB) boundary file as an ArcInfo® coverage.
  2. Import the population counts and land area, and then calculate the population density – all in Access.
  3. Import the output table into ArcGIS™ and add an ecumene flag. For each dissemination block, impute the flag with a Boolean value of 1 = ecumene (population density is greater than or equal to 0.4 persons per square kilometre) and set the flag value to 0 = non-ecumene for the remaining blocks (population density is less than 0.4 persons per square kilometre).
  4. Merge contiguous ecumene polygons having the same Boolean value using the DISSOLVE function.

Phase 2. Create three ecumene coverages

  1. Core ecumene: select the merged dissemination blocks that are equal to or greater than 1,000 square kilometres.
  2. Ecumene pockets outside the core ecumene: select the merged dissemination blocks that are less than 1,000 square kilometres.
  3. Non-ecumene pockets inside the core ecumene: select the merged pockets that are equal to or greater than 2,000 square kilometres.

Phase 3. Generalize the core ecumene

  1. Generalization procedure: further aggregate neighbouring polygons using the AREAAGGREGATE command, selecting a minimum cell size of 4,000 square metres and a distance of 4,001 metres between cells. Then buffer to 7 kilometres. and smooth the outer edge using the GENERALIZE command, selecting the BENDSIMPLIFY option.
  2. Visually inspect the output for quality. When major non-ecumene pockets are absorbed into the core ecumene, select and export the pocket in question to create a new file containing only the core ecumene. Update the ecumene flag from 1 to 0, then buffer to 2 kilometres. Smooth using the GENERALIZE command with the BENDSIMPLIFY option. A WEED tolerance of 40,000 metres is used.
  3. Attributes are lost during the manipulation. To remedy this, convert the shapefile to a coverage. Using ArcGIS™ employ ADDITEM to add the ecumene field. Then utilize the CALC command in INFO to convert to ecumene = 1.
  4. Visually inspect the output for quality. Small polygons which are present in the core ecumene but should be non-ecumene must be converted using the CALC command, setting the value to 0. Any small polygons and slivers with a value of 0 must be absorbed into the core ecumene.
  5. Convert the coverage back to a shapefile.

Phase 4. Generalize the ecumene pockets outside the core ecumene

  1. Generalization procedure A: manually remove extraneous small polygons. (This part of the procedure is not automated to ensure important communities are not removed.) Select ecumene island pockets using printed maps of the 2001 ecumene and the current core ecumene (CE), displaying the 2006 CD boundaries for reference. Due to the large number of polygons that needs to be selected, this procedure is done three times (covering different geographical areas—north, east and west). Merge the three coverages using the APPEND command.
  2. Generalization procedure B: further aggregate neighbouring polygons using the AREAAGGREGATE command, selecting a minimum cell size of 4,000 square metres and a distance of 4,001 metres between cells.
  3. Select coastal polygons which are to be clipped by the shoreline, and BUFFER them by 5 kilometres.
  4. Visually inspect the output for quality. Put back any small polygons that are dropped during the AREAAGGREGATE procedure by selecting the missing polygons.
  5. Convert the coverage back to a shapefile.

Phase 5. Generalize the non-ecumene pockets inside the core ecumene

  1. Generalization procedure: further aggregate neighbouring polygons using the AREAAGGREGATE command, selecting a minimum cell size of 2,000 square metres and a distance of 2,001 metres between cells.
  2. Exaggerate the non-ecumene pockets using BUFFER to 2 kilometres. Smooth the outline using the BENDSIMPLIFY option of the GENERALIZE command.
  3. Convert the coverage back to a shapefile.

Phase 6. Assemble final ecumene

  1. Integrate the final three layers to produce the final product with a two-step process. Use IDENTITY to merge the core ecumene and the ecumene pockets outside the core ecumene. Use IDENTITY to insert the non-ecumene pockets inside the core ecumene.
  2. CLEAN and BUILD the resulting shapefile.