Methodology and Interpretation

Percent interior forest
Percentage of forest interior is calculated using a moving 270-meter-square window (9 pixels x 9 pixels) across the land cover. When the entire window contains forest cover, the forest cell in the center of the window is classified as interior. The number of interior forest cells in the reporting unit is then divided by the reporting unit's total land area (i.e., the total number cells in the reporting unit boundary minus those cells classified as water) to derive the percentage of interior forest. Interior forest is required habitat for many 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