Ecosystem management decision support for road system analysis and reserve design in the Sierra Nevada

Roads pose immediate threats to the bio-physical integrity of landscapes, wildlife movement, ecological flows, aquatic systems, and geomorphic processes. Although these types of impacts are recognized by many in research and applied settings, the incorporation of knowledge of these impacts into decision-making is not well worked out. I have used the GIS tool “Ecosystem Management Decision Support” (EMDS) to evaluate the combined effects of roads and road system on natural systems in the context of explicit management goals. In the first case, I will describe the use of EMDS to aggregate spatial data describing potential effects of roads in the Tahoe National Forest (TNF) for the Forest’s Roads Analysis Project. These effects included fragmentation effects on species of concern, aquatic systems, and landscape connectivity. The Forest still uses the product of this modeling 3 years later for decision-making about road removal. In a second case, road effects were considered in an analysis of landscape integrity as part of a reserve network design for the Sierra Nevada, Modoc Plateau, and Southern Cascade eco-regions. This approach is reflected in the proposed California statewide connectivity analysis. This tool is an example of an approach to bring together multiple goals and types of impacts to re-design road systems and landscapes.