Home Study Area Data Collection Methodology Spatial Analysis Methodological & Operational Problems

Collection of Data

SOURCE:

The data was collected in MapInfo format from the Township of Langley.  It was initially in vector format but was translated into ArcView vector format, and then Idrisi raster format.  

METADATA:

The parcels data that was used to form the land use, schools, and developed areas layers is current to November, 2002 and the road centres layer is current to April, 2002.  The waterways layer was also current to April, 2002.  Since it takes time for the criteria involved in the analysis to change, the data was up to date.  Due to the fact that land use is the fastest changing factor in my analysis (waterways, ALR boundaries, and roads take time to change) the recency of that layer contributed to a good analysis.

The data was originally projected using the Transverse Mercator projection.

DATA PROBLEMS:

In the parcels layer certain parcels were lacking actual use codes which prevented me from knowing what land use they were.  Parcels without actual use codes that had their folio listed as Strata or that were located in residential lots were chosen as residential.  The other lots of unknown land use were listed as Developable if they covered 2.00 acres or more or undevelopable if they covered less than 2.00 acres.

DATA MANIPULATION:

The residential land use parcels were split up further into high density residential and low density residential where low density encompassed properties of 2.00 acres or more.  This process was accomplished using ArcView before the data was imported into Idrisi.  For the study only low density residential areas were considered developable.

The parcels layer was queried in ArcView so that I could separate all of the parcels used as schools from the rest of the parcels.  This is how I made the schools layer.

The parcels layer was also altered in Idrisi in order to separate developable lands from undevelopable lands and developed lands from undeveloped lands.  This was done by conducting a Boolean re-classification.