Methodology and Interpretation

Percent edge forest
Percentage of edge forest is calculated using a moving 270-meter-square window (9 pixels x 9 pixels) across the land cover. When the percent forest in the window is greater than 60%, but less than the window's mean forest connectivity value, the forest cell in the center of the window is classified as edge. The number of edge forest cells in the reporting unit is then divided by the reporting unit's total land area (the total number cells in the reporting unit boundary minus those cells classified as water) to derive the percentage of edge forest. Edge forest indicates largely continuous, clumped forest, which is more likely to provide increased opportunities for upland forest animal movement and upland forest plant dispersal, but may or may not provide suitable interior habitat, depending on the species. It is important to recognize that increased amounts of edge may increase the likelihood of invasive (i.e., non-native) or opportunistic (i.e., native) animal or plant species occurrences within a forest, and may result in decreased animal or plant diversity.

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