These layers each depict one suite of methodological choices for designating land facets. Scroll through them to see how different choices affect land facet patterns.
Methodological choices:
Resolution: 1km or 270m
Categorization approach:
- Categorical overlay- each variable is categorized into ecologically meaningful classes. Land facets are created from unique combinations of those classes.
- K-means clustering- an algorithm clusters the continuous variables into a designated number of facets. The Hartigan index was used to identify the optimal number of facets.
- Hybrid approach- a combination of the categorical overlay and a clustering method. Topographic data were categorized, and within each topographic class all other variables were clustered using a fuzzy c-means algorithm
Variable selection:
- Topographic variables
- Soil variables
- organic matter
- bulk density
- soil horizon depth
- accumulated water content
- Geology (categorized into 9 types of geological groupings after Anderson)
Normalization: variables normalized (where necessary) within ecoregion or across 14 NW ecoregions