Relationship between forest edge habitat and abundance - thoughts or suggestions ?

Discussion created by jstruve on Oct 10, 2011
Latest reply on Oct 11, 2011 by jstruve
Dear ArcGIS people,

I am trying to figure out how to examine the effect of forest edge habitat (independent variable) onto the abundance of certain species (dependent variable) associated with those edges. Abundance data consist of spatially distributed counts in a study area that includes the edge habitat and large spaces without it.

It is believed that the habitat effect may include not only presence of the edge habitat, but also length of the edge and possibly width. Complexity of the shape of the edge may also play a role.

I am looking at different ways to describe the habitat effect and have so far come up with:
1. Distance from the habitat edge
2. Presence of certain tree species within the immediate neighborhood of the dependent variable, defined as a round buffer.

I am thinking of intersecting the buffers with the edge habitat feature, and to make the neighborhood succcessively larger in order to test if the effect of the edge habitat onto abundance may be dependent on the scale of observation.

I was wondering if anyone has experience with such analysis, and what problems may arise. There are a lot of zeros in the data where no animals were found.  I have not figured out yet how to describe the complexite of the edge itself. It appears that the Patch Analyst extension was written for some related questions, but I have not been able to download it for ArcGIS 10.

Thank you very muh for any suggestions and best wishes,