Southern Blue Ridge: An Analysis of Matrix Forests - Conservation ...

We developed a four-step analysis process to assess, prioritize, and direct conservation strategies toprotect the Southern Blue Ridge matrix forest system:• Delineate matrix forest blocks to identify and subdivide the forested landscape into discrete blocksof contiguous forest, using roads and other fragmenting features in GIS.• Screen each matrix forest block for size and condition using land cover and size criteria, related todisturbance and species’ needs.• Classify the candidate matrix forest blocks into multiple groups that reflect similar combinations ofelevation, geology, and landforms (Ecological Land Units).• Evaluate and prioritize a network of functional matrix forest blocks representative of the diversityof ecoregional forest landscape types, using additional data and expert review.DELINEATING MATRIX FOREST BLOCKSUsing GIS data, we subdivided the entire forested landscape of the Southern Blue Ridge into discreteunits (“matrix forest blocks”), bounded on all sides by major roads (road classes 1-4; ESRI 2009), lakes,or large rivers (>3,681m 2 drainage area) (USEPA and USGS 2008) (Table 1 and Appendix B). Roads werean appropriate choice for this task, as they disrupt the movement of some organisms and the flow ofsome ecological processes, and they increase the level of access into interior forest areas. Additionally,we analyzed and sometimes adjusted blocks according to the location of roads, railroads, powerlines,logging trails, housing developments, agricultural lands, and mining operations from obtained digitaldata or aerial imagery (Table 1) that can be highly correlated with human natural resource extractive orother ecologically-incompatible activities that can impair connectivity and forest processes. DelineatedSBR matrix forest blocks were bounded on all sides by connected fragmenting roads (or other features),forming polygons that completely encircled large contiguous patches of forest. However, delineatedblocks are not necessarily roadless, as blocks can contain intersecting roads (roads that extend intoblock boundaries, but do not bisect the block).6