Methodology and Interpretation
The percentage of forest land cover is calculated by dividing the number of forest land cover
cells in the reporting unit by the total number of land cover cells in the reporting unit
minus those cells classified as water (i.e., total land area). Forests may remove or reduce
the amount of pollutants entering streams and lakes. Forests also provide habitat for a wide
variety of plant and animal species.
Quantile: Each class contains an approximately equal number (count) of features. A quantile
classification is well-suited to linearly distributed data. Because features are grouped by the number
within each class, the resulting map can be misleading, in that similar features can be separated into
adjacent classes, or features with widely different values can be lumped into the same class. This
distortion can be minimized by increasing the number of classes.
Metric input GIS data:
- United States Hydrologic Units (8-digit HUCs) - Metadata
- United States Coastal Change Analysis Program (CCAP) - Metadata
- Canada Hydrologic Units (Subsubdivisions) - Metadata
- Ontario Ministry of Natural Resources Data Set - Metadata