Did you ever wonder how to quantitatively analyze the quality, shape, and degree of connectivity of natural habitats? Well, there’s an open source app for that, called FRAGSTATS, and good documentation that describes the theory behind it. To summarize, it looks at area and edge, shape, core area, contrast, aggregation, and diversity. Here are just a few quotes describing some of the metrics.

“Core area is defined as the area within a patch beyond some specified depth-of-edge influence (i.e., edge distance) or buffer width.”

“Contrast refers to the magnitude of difference between adjacent patch types with respect to one or more ecological attributes at a given scale that are relevant to the organism or process under consideration.”

“Aggregation refers to the tendency of patch types to be spatially aggregated; that is,
to occur in large, aggregated or “contagious” distributions.”

“FRAGSTATS computes 3 diversity indices. These diversity measures are influenced by 2 components- richness and evenness. Richness refers to the number of patch types present; evenness refers to the distribution of area among different types.”